Predicting high-risk preterm birth using artificial neural networks.

PubMed

Catley, Christina; Frize, Monique; Walker, C Robin; Petriu, Dorina C

2006-07-01

A reengineered approach to the early prediction of preterm birth is presented as a complimentary technique to the current procedure of using costly and invasive clinical testing on high-risk maternal populations. Artificial neural networks (ANNs) are employed as a screening tool for preterm birth on a heterogeneous maternal population; risk estimations use obstetrical variables available to physicians before 23 weeks gestation. The objective was to assess if ANNs have a potential use in obstetrical outcome estimations in low-risk maternal populations. The back-propagation feedforward ANN was trained and tested on cases with eight input variables describing the patient's obstetrical history; the output variables were: 1) preterm birth; 2) high-risk preterm birth; and 3) a refined high-risk preterm birth outcome excluding all cases where resuscitation was delivered in the form of free flow oxygen. Artificial training sets were created to increase the distribution of the underrepresented class to 20%. Training on the refined high-risk preterm birth model increased the network's sensitivity to 54.8%, compared to just over 20% for the nonartificially distributed preterm birth model.

Pre-eclampsia and preterm birth in Reunion Island: a 13 years cohort-based study. Comparison with international data.

PubMed

Iacobelli, Silvia; Bonsante, Francesco; Robillard, Pierre-Yves

2016-09-01

To assess the prevalence of preterm birth in pre-eclamptic deliveries in Reunion Island, a tropical overseas French department (départements d'outre-mer, DOM) and to compare this prevalence with that of international literature. All singleton live-born deliveries referred to three maternity centers in Reunion Island over 13 years were eligible. Data for comparison were found through searches of MEDLINE, bibliographies of identified studies, proceedings of meetings on pre-eclampsia and contact with relevant researchers. Incidence of pre-eclampsia, proportion of preterm (<37(0/7) weeks gestation), late (34(0/7)-36(6/7) weeks) and early (<34(0/7) weeks) preterm birth in pre-eclamptic deliveries were analyzed. Pre-eclampsia occurred in 2.3% of 51 927 singleton live-born deliveries in Reunion Island. The prevalence of preterm birth among pre-eclamptic deliveries was 59.8% (28.6% late and 31.2% early preterm birth). Among identified reports, only one prospective study from Canada (1986-1995) described preterm and early preterm birth rates higher than Reunion Island. A cohort-based report from Guadeloupe, another tropical French DOM, showed a preterm birth prevalence of 60.9%, with 30.8% of early preterm birth. Predominance of early- or late-onset pre-eclampsia has huge geographical differences. Further investigations are required to address risk factors for preterm birth and early onset pre-eclampsia in French DOM.

The relationship of the subtypes of preterm birth with retinopathy of prematurity.

PubMed

Lynch, Anne M; Wagner, Brandie D; Hodges, Jennifer K; Thevarajah, Tamara S; McCourt, Emily A; Cerda, Ashlee M; Mandava, Naresh; Gibbs, Ronald S; Palestine, Alan G

2017-09-01

Retinopathy of prematurity is an adverse outcome of preterm birth and is a leading cause of childhood blindness. The relationship between the subtypes of preterm birth with retinopathy of prematurity is understudied. To investigate whether there is a difference in the incidence of type 1 or type 2 retinopathy of prematurity in infants with preterm birth resulting from spontaneous preterm labor, a medical indication of preterm birth, or preterm premature rupture of the membranes. A retrospective cohort study was conducted of 827 infants screened for retinopathy of prematurity who were delivered at a single tertiary care center in Colorado. All infants fulfilled the American Academy of Pediatrics 2013 screening criteria for retinopathy of prematurity defined as "infants with a birth weight of ≤1500 g or gestational age of 30 weeks or less (as defined by the attending neonatologist) and selected infants with a birth weight between 1500 and 2000 g or gestational age of >30 weeks with an unstable clinical course, including those requiring cardiorespiratory support and who are believed by their attending pediatrician or neonatologist to be at high risk for retinopathy of prematurity." Two independent reviewers masked to retinopathy of prematurity outcomes determined whether preterm birth resulted from spontaneous preterm labor, medical indication of preterm birth, or preterm premature rupture of the membranes. Discrepancies were resolved by a third reviewer. Data were analyzed with univariate and multivariable logistic regression. In our cohort, the frequency of preterm birth resulting from spontaneous preterm labor, medical indication of preterm birth, or preterm premature rupture of the membranes was 34%, 40%, and 26%, respectively. The mean gestational age (weeks, days) ± SD (range) in the cohort and across the preterm birth subtypes was as follows: entire cohort, 28 weeks, 6 days ± 2 weeks, 3 days (23 weeks, 3 days - 36 weeks, 4 days); spontaneous preterm labor, 28 weeks 1 day ± 2 weeks, 3 days (23 weeks, 3 days - 33 weeks, 4 days); medical indication of preterm birth, 29 weeks, 1 day ± 2 weeks, 2 days (24-36 weeks, 4 days); preterm premature rupture of the membranes, 28 weeks, 4 days ± 2 weeks, 1 day (24-33 weeks, 1 day). Among infants with type 1, type 2, or no retinopathy of prematurity, the incidence of type 1 or type 2 retinopathy of prematurity in births from spontaneous preterm labor, medical indication of preterm birth, and preterm premature rupture of the membranes was 37 of 218 (17%), 27 of 272 (10%), and 10 of 164 (6%), respectively. Adjusted for gestational age, birth weight, and multiparity and compared with the preterm premature rupture of the membranes group, the odds ratios of spontaneous preterm labor and medical indication of preterm birth for type 1 or type 2 retinopathy of prematurity were 6.1 (95% confidence interval, 1.8 to 20, P = .003) and 5.5 (95% confidence interval, 1.4 to 21, P = .01), respectively. Among neonates born after preterm premature rupture of the membranes, the probability of developing type 1 or type 2 retinopathy of prematurity was greatest in infants with rupture of membrane duration of up to 24 hours. After 24 hours, the probability of developing type 1 or type 2 retinopathy of prematurity declined. The odds of developing type 1 or type 2 retinopathy of prematurity was 9.0 (95% confidence interval 2.3 to 34, P = .002) in infants who had preterm premature rupture of the membranes ≤ 24 hours compared with infants who had preterm premature rupture of the membranes > 24 hours. Type 1 or type 2 retinopathy of prematurity are adverse ocular outcomes linked with not only lower gestational age and birth weight at delivery but also with events in the intrauterine environment that trigger a preterm birth. The reduced incidence of type 1 or type 2 retinopathy of prematurity in the preterm premature rupture of the membranes group compared with other causes of preterm birth may be related to the perinatal therapies associated with preterm premature rupture of the membranes (such as corticosteroids, antibiotics, maternal-fetal surveillance), which may have an inhibitory effect on the development of retinopathy of prematurity. We suggest that the physiologic events that predispose infants to type 1 or type 2 retinopathy of prematurity begin before delivery. Copyright © 2017 Elsevier Inc. All rights reserved.

Time from cervical conization to pregnancy and preterm birth.

PubMed

Himes, Katherine P; Simhan, Hyagriv N

2007-02-01

To estimate whether the time interval between cervical conization and subsequent pregnancy is associated with risk of preterm birth. Our study is a case control study nested in a retrospective cohort. Women who underwent colposcopic biopsy or conization with loop electrosurgical excision procedure, large loop excision of the transformation zone, or cold knife cone and subsequently delivered at our hospital were identified with electronic databases. Variables considered as possible confounders included maternal race, age, marital status, payor status, years of education, self-reported tobacco use, history of preterm delivery, and dimensions of cone specimen. Conization was not associated with preterm birth or any subtypes of preterm birth. Among women who underwent conization, those with a subsequent preterm birth had a shorter conization-to-pregnancy interval (337 days) than women with a subsequent term birth (581 days) (P=.004). The association between short conization-to-pregnancy interval and preterm birth remained significant when controlling for confounders including race and cone dimensions. The effect of short conization-to-pregnancy interval on subsequent preterm birth was more persistent among African Americans when compared with white women. Women with a short conization-to-pregnancy interval are at increased risk for preterm birth. Women of reproductive age who must have a conization procedure can be counseled that conceiving within 2 to 3 months of the procedure may be associated with an increased risk of preterm birth. II.

Postpartum contraceptive use among women with a recent preterm birth.

PubMed

Robbins, Cheryl L; Farr, Sherry L; Zapata, Lauren B; D'Angelo, Denise V; Callaghan, William M

2015-10-01

The objective of the study was to evaluate the associations between postpartum contraception and having a recent preterm birth. Population-based data from the Pregnancy Risk Assessment Monitoring System in 9 states were used to estimate the postpartum use of highly or moderately effective contraception (sterilization, intrauterine device, implants, shots, pills, patch, and ring) and user-independent contraception (sterilization, implants, and intrauterine device) among women with recent live births (2009-2011). We assessed the differences in contraception by gestational age (≤27, 28-33, or 34-36 weeks vs term [≥37 weeks]) and modeled the associations using multivariable logistic regression with weighted data. A higher percentage of women with recent extreme preterm birth (≤27 weeks) reported using no postpartum method (31%) compared with all other women (15-16%). Women delivering extreme preterm infants had a decreased odds of using highly or moderately effective methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.6) and user-independent methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.7) compared with women having term births. Wanting to get pregnant was more frequently reported as a reason for contraceptive nonuse by women with an extreme preterm birth overall (45%) compared with all other women (15-18%, P < .0001). Infant death occurred in 41% of extreme preterm births and more than half of these mothers (54%) reported wanting to become pregnant as the reason for contraceptive nonuse. During contraceptive counseling with women who had recent preterm births, providers should address an optimal pregnancy interval and consider that women with recent extreme preterm birth, particularly those whose infants died, may not use contraception because they want to get pregnant. Published by Elsevier Inc.

Preterm birth rates in Japan from 1979 to 2014: Analysis of national vital statistics.

PubMed

Sakata, Soyoko; Konishi, Shoko; Ng, Chris Fook Sheng; Watanabe, Chiho

2018-03-01

Secular trends of preterm birth in Japan between 1979 and 2014 were examined to determine whether changes could be explained by a shift in the distribution of maternal age at delivery and parity and/or by changes in age-specific preterm birth rates. Live birth data for 1979 to 2014 were obtained from the Japanese Ministry of Health, Labour and Welfare. Analyses were limited to singleton children born in Japan (n = 43 632 786). Preterm birth was defined using two cut-offs at < 37 or < 34 weeks of gestation. Crude and standardized rates of preterm birth were calculated for firstborn and later-born singletons by maternal age at delivery for specific time periods. Throughout the study period, the rates of preterm birth (both at < 37 and < 34 weeks of gestation) were higher among mothers aged 20 and younger, and mid-30s and older, compared to mothers in their 20s or early 30s. The rates of preterm birth at < 37 (but not at < 34) weeks decreased for mothers aged in their late 30s and 40s, and increased for mothers in their 20s and early 30s. Standardized rates of preterm birth showed a secular increase for preterm births at < 37 but not < 34 weeks of gestation. The rates of preterm birth among mothers aged in their 20s and early 30s increased between 1979 and 2014, which contributed to the secular increase in rates of preterm birth at < 37 weeks. © 2017 Japan Society of Obstetrics and Gynecology.

Impact of stillbirths on international comparisons of preterm birth rates: a secondary analysis of the WHO multi-country survey of Maternal and Newborn Health.

PubMed

Morisaki, N; Ganchimeg, T; Vogel, J P; Zeitlin, J; Cecatti, J G; Souza, J P; Pileggi Castro, C; Torloni, M R; Ota, E; Mori, R; Dolan, S M; Tough, S; Mittal, S; Bataglia, V; Yadamsuren, B; Kramer, M S

2017-08-01

To evaluate the extent to which stillbirths affect international comparisons of preterm birth rates in low- and middle-income countries. Secondary analysis of a multi-country cross-sectional study. 29 countries participating in the World Health Organization Multicountry Survey on Maternal and Newborn Health. 258 215 singleton deliveries in 286 hospitals. We describe how inclusion or exclusion of stillbirth affect rates of preterm births in 29 countries. Preterm delivery. In all countries, preterm birth rates were substantially lower when based on live births only, than when based on total births. However, the increase in preterm birth rates with inclusion of stillbirths was substantially higher in low Human Development Index (HDI) countries [median 18.2%, interquartile range (17.2-34.6%)] compared with medium (4.3%, 3.0-6.7%), and high-HDI countries (4.8%, 4.4-5.5%). Inclusion of stillbirths leads to higher estimates of preterm birth rate in all countries, with a disproportionately large effect in low-HDI countries. Preterm birth rates based on live births alone do not accurately reflect international disparities in perinatal health; thus improved registration and reporting of stillbirths are necessary. Inclusion of stillbirths increases preterm birth rates estimates, especially in low-HDI countries. © 2017 World Health Organization, licensed by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.

PMTCT Option B+ Does Not Increase Preterm Birth Risk and May Prevent Extreme Prematurity: A Retrospective Cohort Study in Malawi.

PubMed

Chagomerana, Maganizo B; Miller, William C; Pence, Brian W; Hosseinipour, Mina C; Hoffman, Irving F; Flick, Robert J; Tweya, Hannock; Mumba, Soyapi; Chimbwandira, Frank; Powers, Kimberly A

2017-04-01

To estimate preterm birth risk among infants of HIV-infected women in Lilongwe, Malawi, according to maternal antiretroviral therapy (ART) status and initiation time under Option B+. A retrospective cohort study of HIV-infected women delivering at ≥27 weeks of gestation, April 2012 to November 2015. Among women on ART at delivery, we restricted our analysis to those who initiated ART before 27 weeks of gestation. We defined preterm birth as a singleton live birth at ≥27 and <37 weeks of gestation, with births at <32 weeks classified as extremely to very preterm. We used log-binomial models to estimate risk ratios and 95% confidence intervals for the association between ART and preterm birth. Among 3074 women included in our analyses, 731 preterm deliveries were observed (24%). Overall preterm birth risk was similar in women who had initiated ART at any point before 27 weeks and those who never initiated ART (risk ratio = 1.14; 95% confidence interval: 0.84 to 1.55), but risk of extremely to very preterm birth was 2.33 (1.39 to 3.92) times as great in those who never initiated ART compared with those who did at any point before 27 weeks. Among women on ART before delivery, ART initiation before conception was associated with the lowest preterm birth risk. ART during pregnancy was not associated with preterm birth, and it may in fact be protective against severe adverse outcomes accompanying extremely to very preterm birth. As preconception ART initiation appears especially protective, long-term retention on ART should be a priority to minimize preterm birth in subsequent pregnancies.

Effect(s) of preterm birth on normal retinal vascular development and oxygen-induced retinopathy in the neonatal rat.

PubMed

Li, Rong; Yang, Xiangmin; Wang, Yusheng; Chu, Zhaojie; Liu, Tao; Zhu, Tong; Gao, Xiang; Ma, Zhen

2013-12-01

Maturity is a critical factor in the pathogenesis of retinopathy of prematurity (ROP). One widely used method for studying this condition is that of oxygen-induced retinopathy (OIR). The general conditions of an OIR term animal, both at the time of birth and following birth, differ from those of the preterm infant. This, to simulate preterm conditions and to provide a basis for further studies on ROP, we investigated the effect(s) of preterm birth on retinal vascularization using the neonatal rat. Sprague-Dawley (SD) rats were delivered preterm by caesarean section on the day 19 of gestation. Term pups were used as controls. On the day of birth, preterm and term pups were housed under conditions of room air or cyclic oxygen. Retinas of pups housed in room air on days 4, 7, 10, 14, 18 and 22, as well as pups housed in oxygen on days 14, 18, and 22 were whole-mounted and stained with isolectin-B4. On day 18, cross-sections of the retina were cut and stained with hematoxylin and eosin for the identification of preretinal neovascular tufts. Images of avascular and neovascular areas were compared using light and fluorescence microscopy. Preterm pups had significantly larger avascular retinal areas than term rats on the various postnatal days. After exposure to cyclic oxygen, preterm pups demonstrated significantly larger avascular (days 14 and 18) and neovascular areas (day 18) compared with term rats. On day 22, residual retinopathy of preterm pups was greater than that of term pups. Preterm birth of rats, which are comparable in their physiology to humans, had negative effects on retinal vascularization. The impaired retinal vascular development and subsequent vasoproliferation resulting from hyperoxia in preterm pups is more severe and enduring.

International variations in the gestational age distribution of births: an ecological study in 34 high-income countries.

PubMed

Delnord, Marie; Mortensen, Laust; Hindori-Mohangoo, Ashna D; Blondel, Béatrice; Gissler, Mika; Kramer, Michael R; Richards, Jennifer L; Deb-Rinker, Paromita; Rouleau, Jocelyn; Morisaki, Naho; Nassar, Natasha; Bolumar, Francisco; Berrut, Sylvie; Nybo Andersen, Anne-Marie; Kramer, Michael S; Zeitlin, Jennifer

2018-04-01

Few studies have investigated international variations in the gestational age (GA) distribution of births. While preterm births (22-36 weeks GA) and early term births (37-38 weeks) are at greater risk of adverse health outcomes compared to full term births (39-40 weeks), it is not known if countries with high preterm birth rates also have high early term birth rates. We examined rate associations between preterm and early term births and mean term GA by mode of delivery onset. We used routine aggregate data on the GA distribution of singleton live births from up to 34 high-income countries/regions in 1996, 2000, 2004, 2008 and 2010 to study preterm and early term births overall and by spontaneous or indicated onset. Pearson correlation coefficients were adjusted for clustering in time trend analyses. Preterm and early term births ranged from 4.1% to 8.2% (median 5.5%) and 15.6% to 30.8% (median 22.2%) of live births in 2010, respectively. Countries with higher preterm birth rates in 2004-2010 had higher early term birth rates (r > 0.50, P < 0.01) and changes over time were strongly correlated overall (adjusted-r = 0.55, P < 0.01) and by mode of onset. Positive associations between preterm and early term birth rates suggest that common risk factors could underpin shifts in the GA distribution. Targeting modifiable population risk factors for delivery before 39 weeks GA may provide a useful preterm birth prevention paradigm.

An overview of morbidity, mortality and long-term outcome of late preterm birth.

PubMed

Dong, Ying; Yu, Jia-Lin

2011-08-01

Preterm birth rate continues to rise around the world mainly at the expense of late preterm newborns, recently defined as births between the gestational age of 34 weeks and 36-6/7 weeks. Late preterm infants are considered to have significantly more short-term and longterm adverse outcomes than term infants. Articles concerning morbidity, mortality and long-term outcomes of late preterm infants were retrieved from PubMed/MEDLINE published during the period of 2000-2010. Late preterm infants are the fastest growing subgroup of neonates, comprising the majority of all preterm births. Compared with term infants, they have significantly higher risk of morbidity, mortality and adverse long-term outcomes well beyond infancy into adulthood. However, epidemiology and etiology of late preterm births, the magnitude of their morbidity, the long-term life quality, and public health impact have not been well studied. The growing number of late preterm neonates substantiates the importance to better understand and medically approach this special preterm subgroup. A long-term evaluation, monitoring and follow-up of late preterm infants are needed to optimize neonatal care and improve human health status.

Bacterial Hyaluronidase Promotes Ascending GBS Infection and Preterm Birth.

PubMed

Vornhagen, Jay; Quach, Phoenicia; Boldenow, Erica; Merillat, Sean; Whidbey, Christopher; Ngo, Lisa Y; Adams Waldorf, K M; Rajagopal, Lakshmi

2016-06-28

Preterm birth increases the risk of adverse birth outcomes and is the leading cause of neonatal mortality. A significant cause of preterm birth is in utero infection with vaginal microorganisms. These vaginal microorganisms are often recovered from the amniotic fluid of preterm birth cases. A vaginal microorganism frequently associated with preterm birth is group B streptococcus (GBS), or Streptococcus agalactiae However, the molecular mechanisms underlying GBS ascension are poorly understood. Here, we describe the role of the GBS hyaluronidase in ascending infection and preterm birth. We show that clinical GBS strains associated with preterm labor or neonatal infections have increased hyaluronidase activity compared to commensal strains obtained from rectovaginal swabs of healthy women. Using a murine model of ascending infection, we show that hyaluronidase activity was associated with increased ascending GBS infection, preterm birth, and fetal demise. Interestingly, hyaluronidase activity reduced uterine inflammation but did not impact placental or fetal inflammation. Our study shows that hyaluronidase activity enables GBS to subvert uterine immune responses, leading to increased rates of ascending infection and preterm birth. These findings have important implications for the development of therapies to prevent in utero infection and preterm birth. GBS are a family of bacteria that frequently colonize the vagina of pregnant women. In some cases, GBS ascend from the vagina into the uterine space, leading to fetal injury and preterm birth. Unfortunately, little is known about the mechanisms underlying ascending GBS infection. In this study, we show that a GBS virulence factor, HylB, shows higher activity in strains isolated from cases of preterm birth than those isolates from rectovaginal swabs of healthy women. We discovered that GBS rely on HylB to avoid immune detection in uterine tissue, but not placental tissue, which leads to increased rates of fetal injury and preterm birth. These studies provide novel insight into the underlying mechanisms of ascending infection. Copyright © 2016 Vornhagen et al.

What contributes to disparities in the preterm birth rate in European countries?

PubMed Central

Delnord, Marie; Blondel, Béatrice; Zeitlin, Jennifer

2015-01-01

Purpose of review In countries with comparable levels of development and healthcare systems, preterm birth rates vary markedly – a range from 5 to 10% among live births in Europe. This review seeks to identify the most likely sources of heterogeneity in preterm birth rates, which could explain differences between European countries. Recent findings Multiple risk factors impact on preterm birth. Recent studies reported on measurement issues, population characteristics, reproductive health policies as well as medical practices, including those related to subfertility treatments and indicated deliveries, which affect preterm birth rates and trends in high-income countries. We showed wide variation in population characteristics, including multiple pregnancies, maternal age, BMI, smoking, and percentage of migrants in European countries. Summary Many potentially modifiable population factors (BMI, smoking, and environmental exposures) as well as health system factors (practices related to indicated preterm deliveries) play a role in determining preterm birth risk. More knowledge about how these factors contribute to low and stable preterm birth rates in some countries is needed for shaping future policy. It is also important to clarify the potential contribution of artifactual differences owing to measurement. PMID:25692506

A comparison of risk factors for twin preterm birth in the United States between 1981-82 and 1996-97.

PubMed

Kogan, Michael D; Alexander, Greg R; Kotelchuck, Milton; MacDorman, Marian F; Buekens, Pierre; Papiernik, Emile

2002-03-01

This paper examines risk factors for twin preterm birth in 1981-82 and 1996-97 in the United States in order to see if they have changed over time. We studied all U.S. twin births for the years examined (N = 346, 567). Since the gestational age distributions for twins differs from singletons, the risk of preterm birth was examined at <33, 33-34, and 35-36 weeks. Logistic regression was used to examine the contributions of sociodemographic and obstetric factors at each period. While the <33 week twin preterm rate rose 7% from 1981-82 to 1996-97, the 33-34-week rate rose 31%, and the 35-36-week rate rose 51%. Women with less education, teenagers, unmarried women, primiparas, and blacks were more likely to deliver preterm across all three preterm birth levels. However, the effect of these low socioeconomic status markers diminished over the study period. Additionally, the odds of preterm birth among blacks increased with earlier gestational ages. Women who had intensive prenatal care utilization as compared with less than adequate utilization were more likely to deliver preterm (35-36 weeks) in 1996-97 (odds ratio (OR) = 2.05) compared with 1981-82 (OR = 1.44). Smaller increases were noted for <33 and 33-34 weeks. Obstetric factors appear to be playing a greater role in the rise of twin preterm births at 35-36 weeks gestation. Temporal sociodemographic changes do not explain the rise in the preterm rate. Changing clinical practices may be having unintended consequences on the public health goals of reducing preterm and low birthweight rates in the United States.

The epidemiology, etiology, and costs of preterm birth.

PubMed

Frey, Heather A; Klebanoff, Mark A

2016-04-01

After decades of rising preterm birth rates in the USA and other countries, recent prematurity rates seem to be on the decline. Despite this optimistic trend, preterm birth rates remain higher in the USA, where nearly one in every eight infants is born early, compared to other developed countries. The prevention of preterm birth is considered a public health priority because of the potential to reduce infant and childhood morbidity and mortality related to this condition. Unfortunately, progress has been modest. One of the greatest challenges in studying this outcome is that preterm birth is a complex condition resulting from multiple etiologic pathways. Recently, experts have developed innovative frameworks for classifying and studying preterm birth based on phenotype. These proposed classification systems have only recently been adopted, but a different perspective on a longstanding problem has the potential to lead to new discoveries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cost of Racial Disparity in Preterm Birth: Evidence from Michigan

PubMed Central

Xu, Xiao; Grigorescu, Violanda; Siefert, Kristine A.; Lori, Jody R.; Ransom, Scott B.

2009-01-01

This study examined the economic costs associated with racial disparity in preterm birth and preterm fetal death in Michigan. Linked 2003 Michigan vital statistics and hospital discharge data were used for data analysis. Thirteen percent of the singleton births among non-Hispanic Blacks were before 37 completed weeks of gestation, compared to only 7.7% among non-Hispanic Whites (risk ratio = 1.66, 95% confidence interval: 1.59-1.72; p<0.0001). One thousand one hundred and eighty four non-Hispanic Black, singleton preterm births and preterm fetal deaths would have been avoided in 2003 had their preterm birth rate been the same as Michigan non-Hispanic Whites. Economic costs associated with these excess Black preterm births and preterm fetal deaths amounted to $329 million (range: $148 million - $598 million) across their lifespan over and above the costs if they were born at term, including costs associated with the initial hospitalization, productivity loss due to perinatal death, and major developmental disabilities. Hence, racial disparity in preterm birth and preterm fetal death has substantial cost implications for society. Improving pregnancy outcomes for African American women and reducing the disparity between Blacks and Whites should continue to be a focus of future research and interventions. PMID:19648701

Association between high risk for preterm birth and changes in gingiva parameters during pregnancy-a prospective cohort study.

PubMed

Kruse, Anne Brigitte; Kuerschner, Anja C; Kunze, Mirjam; Woelber, Johan P; Al-Ahmad, Ali; Wittmer, Annette; Vach, Kirstin; Ratka-Krueger, Petra

2018-04-01

The objective of this study was to investigate clinical and microbiological gingival changes during pregnancy in women without periodontal disease. Additionally, these parameters were to be compared in women with high risk for preterm birth and women with a normal course of pregnancy. Group I consisted of 40 subjects at high risk for preterm birth, while group II involved 49 subjects with a normal course of pregnancy. The control group (III) was made up of 50 non-pregnant women. Clinical parameters (plaque index, gingival index, probing pocket depths, gingival swelling, bleeding on probing) and microbiological changes were monitored during pregnancy and 2-4 weeks after parturition. In the high-risk preterm group (I), 19 women could be included in data analysis. This group was compared to 41 women in the normal pregnancy group (II) and 50 non-pregnant women (III). Gingival inflammation was significantly higher in women with high risk for preterm birth (I) compared to non-risk pregnant women (II, p < 0.05). In addition, in this group (I), the subgingival amounts of Fusobacterium nucleatum (> 10 5 ) were found to be significantly higher after childbirth compared to non-pregnant women (p < 0.05). Even without having periodontal disease, women with high risk for preterm birth showed worse clinical values compared to non-risk pregnant and non-pregnant women and an increased detection of Fusobacterium nucleatum after delivery. High risk for preterm birth might be associated with the occurrence of increased gingival inflammation.

Association of external cephalic version before term with late preterm birth.

PubMed

Poole, Kristie L; McDonald, Sarah D; Griffith, Lauren E; Hutton, Eileen K

2017-08-01

While evidence suggests that beginning an external cephalic version (ECV) before term (34 0/7 to 36 6/7 weeks) compared with after term may be associated with an increase in late preterm birth (34 0/7 to 36 6/7 weeks), it remains unknown what might account for this risk. The objective of the present study is to further investigate the association between ECV before term and late preterm birth. Secondary analysis of data collected from the international, multicenter Early ECV trials. We evaluated the relation between ECV exposure and late preterm birth (34 0/7 to 36 6/7 weeks), as well as whether additional risk factors for preterm birth (such as maternal age, height, body mass index, parity, placental location, and perinatal mortality rate) moderated this relation. Generalized linear mixed methods were used to account for center effect and adjust for covariates. Among 1765 women with breech pregnancies and without a prior preterm birth, 749 (42.4%) received at least one ECV before term. Exposure to an ECV before term was not associated significantly independently with odds of preterm birth. However, placenta location moderated the association between early ECV exposure and late preterm birth. The odds of preterm birth in women who were exposed to an ECV before term and who also had an anterior placenta were doubled (OR 2.05; 95% CI 1.12-3.71; p = 0.02). In a large cohort of women without known risks for preterm birth, those with an anterior placenta who undergo an ECV before term constitute a subgroup at particular risk for late preterm birth. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

Maternal Vitamin D Insufficiency Early in Pregnancy Is Associated with Increased Risk of Preterm Birth in Ethnic Minority Women in Canada.

PubMed

Tabatabaei, Negar; Auger, Nathalie; Herba, Catherine M; Wei, Shuqin; Allard, Catherine; Fink, Guy D; Fraser, William D

2017-06-01

Background: Maternal vitamin D insufficiency (plasma 25-hydroxyvitamin D [25(OH)D] <75 nmol/L) may play a role in ethnic disparities in rates of preterm and spontaneous preterm births. Objective: We explored the relation between maternal plasma 25(OH)D concentration in the first trimester (8-14 wk of gestation) and the risk of preterm and spontaneous preterm births (<37 wk of gestation) by ethnicity. Methods: We designed a case-control study that included 120 cases of preterm birth (<37 wk of gestation) and 360 term controls (≥37 wk of gestation) of singleton pregnancies from the 3D cohort, a multicenter study in 2456 pregnant women in Quebec, Canada. Plasma 25(OH)D was measured by LC-mass spectrometry. We compared the distribution of vitamin D status between cases and controls for 8 ethnic minority subgroups. We explored the association between maternal plasma 25(OH)D concentration and preterm and spontaneous preterm births with the use of splines in logistic regression by ethnicity. Results: The distributions of maternal vitamin D status (<50, 50-75, and >75 nmol/L) were different in preterm and spontaneous preterm birth cases compared with controls but only in women of ethnic minority ( P- trend = 0.003 and 0.024, respectively). Among ethnic subgroups, sub-Saharan Africans ( P -trend = 0.030) and Arab-West Asians ( P -trend = 0.045) showed an inverse relation between maternal vitamin D status and the risk of preterm birth. Maternal plasma 25(OH)D concentrations of 30 nmol/L were associated with 4.05 times the risk of preterm birth in the total ethnic minority population (95% CI: 1.16, 14.12; P = 0.028) relative to participants with a concentration of 75 nmol/L. In contrast, there was no such association among nonethnic women (OR: 0.94; 95% CI: 0.48, 1.82; P = 0.85). There was no association when we considered only spontaneous preterm births in the total ethnic minority population (OR: 1.75; 95% CI: 0.39, 7.79; P = 0.46). Conclusion: Vitamin D insufficiency is associated with an increased risk of preterm birth in ethnic minority women in Canada. © 2017 American Society for Nutrition.

Provider-Initiated Late Preterm Births in Brazil: Differences between Public and Private Health Services.

PubMed

Leal, Maria do Carmo; Esteves-Pereira, Ana Paula; Nakamura-Pereira, Marcos; Torres, Jacqueline Alves; Domingues, Rosa Maria Soares Madeira; Dias, Marcos Augusto Bastos; Moreira, Maria Elizabeth; Theme-Filha, Mariza; da Gama, Silvana Granado Nogueira

2016-01-01

A large proportion of the rise in prematurity worldwide is owing to late preterm births, which may be due to the expansion of obstetric interventions, especially pre-labour caesarean section. Late preterm births pose similar risks to overall prematurity, making this trend a concern. In this study, we describe factors associated with provider-initiated late preterm birth and verify differences in provider-initiated late preterm birth rates between public and private health services according to obstetric risk. This is a sub-analysis of a national population-based survey of postpartum women entitled "Birth in Brazil", performed between 2011 and 2012. We included 23,472 singleton live births. We performed non-conditional multiple logistic regressions assessing associated factors and analysing differences between public and private health services. Provider-initiated births accounted for 38% of late preterm births; 32% in public health services and 61% in private health services. They were associated with previous preterm birth(s) and maternal pathologies for women receiving both public and private services and with maternal age ≥35 years for women receiving public services. Women receiving private health services had higher rates of provider-initiated late preterm birth (rate of 4.8%) when compared to the ones receiving public services (rate of 2.4%), regardless of obstetric risk-adjusted OR of 2.3 (CI 1.5-3.6) for women of low obstetric risk and adjusted OR of 1.6 (CI 1.1-2.3) for women of high obstetric risk. The high rates of provider-initiated late preterm birth suggests a considerable potential for reduction, as such prematurity can be avoided, especially in women of low obstetric risk. To promote healthy births, we advise introducing policies with incentives for the adoption of new models of birth care.

Preterm birth and adolescent bone mineral content.

PubMed

Erlandson, Marta C; Sherar, Lauren B; Baxter-Jones, Adam D G; Jackowski, Stefan A; Ludwig-Auser, Heidi; Arnold, Chris; Sankaran, Koravangattu

2011-02-01

The purpose of this study was to determine the influence of preterm low birth weight on bone mineral content in adolescence. In 2007 to 2008, data on adolescents were obtained for study, including 16 females and 25 males who were born preterm (≤37 weeks' gestation) between October 1, 1989, and December 31, 1995, with a birth weight of less than 1850 g. Preterm low-birth-weight individuals were age- and sex-matched to full-term (>37 weeks) normal-birth-weight (>2500 g) controls. Total body, hip, and spine bone mineral content (BMC) was assessed using dual energy X-ray absorptiometry. Male preterm individuals had less BMC at the proximal femur in adolescence compared with controls ( p < 0.05). However, once adjusted for age, maturity, height, weight, physical activity, and diet, there were no differences between groups ( p < 0.05) in any bone parameters. These findings suggest that preterm birth and low birth weight did not influence bone accrual in these individuals at adolescence. © Thieme Medical Publishers.

The rate of preterm birth in the United States is affected by the method of gestational age assignment.

PubMed

Duryea, Elaine L; McIntire, Donald D; Leveno, Kenneth J

2015-08-01

The objective of the study was to examine the rate of preterm birth in the United States using 2 different methods of gestational age assignment and determine which method more closely correlates with the known morbidities associated with preterm birth. Using National Center for Health Statistics data from 2012 United States birth certificates, we computed the rate of preterm birth defined as a birth at 36 or fewer completed weeks with gestational age assigned using the obstetric estimate as specified in the revised birth certificate. This rate was then compared with the rate when gestational age is calculated using the last menstrual period alone. The rates of neonatal morbidities associated with preterm birth were examined for each method of assigning gestational age. The rate of preterm birth was 9.7% when the obstetric estimate is used to calculate gestational age, which is significantly different from the rate of 11.5% when gestational age is calculated using the last menstrual period alone. In addition, the neonates identified as preterm by obstetric estimate were more likely to qualify as low birthweight (54% vs 42%; P < .001) and suffer morbidities such as need for assisted ventilation and surfactant use than those identified with the last menstrual period alone. That is to say obstetric estimate is more sensitive and specific for preterm birth by all available markers of prematurity. The preterm birth rate is 9.7% vs 11.5% and more closely correlates with adverse neonatal outcomes associated with preterm birth when gestational age is assigned using the obstetric estimate. This method of gestational age assignment is currently used by most industrialized nations and should be considered for future reporting of US outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

Gestational age-specific perinatal mortality rates for assisted reproductive technology (ART) and other births.

PubMed

Chughtai, Abrar A; Wang, Alex Y; Hilder, Lisa; Li, Zhuoyang; Lui, Kei; Farquhar, Cindy; Sullivan, Elizabeth A

2018-02-01

Is perinatal mortality rate higher among births born following assisted reproductive technology (ART) compared to non-ART births? Overall perinatal mortality rates in ART births was higher compared to non-ART births, but gestational age-specific perinatal mortality rate of ART births was lower for very preterm and moderate to late preterm births. Births born following ART are reported to have higher risk of adverse perinatal outcomes compared to non-ART births. This population-based retrospective cohort study included 407 368 babies (391 952 non-ART and 15 416 ART)-393 491 singletons and 10 877 twins or high order multiples. All births (≥20 weeks of gestation and/or ≥400 g of birthweight) in five states and territories in Australia during the period 2007-2009 were included in the study, using National Perinatal Data Collection (NPDC). Primary outcome measures were rates of stillbirth, neonatal and perinatal deaths. Adjusted odds ratio (AOR) and 95% confidence interval (CI) were used to estimate the likelihood of perinatal death. Rates of multiple birth and low birthweight were significantly higher in ART group compared to the non-ART group (P < 0.01). Overall perinatal mortality rate was significantly higher for ART births (16.5 per 1000 births, 95% CI 14.5-18.6), compared to non-ART births (11.3 per 1000 births, 95% CI 11.0-11.6) (AOR 1.45, 95% CI 1.26-1.68). However, gestational age-specific perinatal mortality rate of ART births (including both singletons and multiples) was lower for very preterm (<32 weeks' gestation) and moderate to late preterm births (32-36 weeks' gestation) (AOR 0.61, 95% CI 0.53-0.70 and AOR 0.61, 95% CI 0.53-0.70, respectively) compared to non-ART births. Congenital abnormality and spontaneous preterm were the most common causes of neonatal deaths in both ART and non-ART group. Due to different cut-off limit for perinatal period in Australia, the results of this study should be interpreted with cautions for other countries. Australian definition of perinatal period commences at 20 completed weeks (140 days) of gestation and ends 27 completed days after birth which is different from the definition by World Health Organisation (commences at 22 completed weeks (154 days) of gestation and ends seven completed days after birth) and by Centers for Disease Control and Prevention (includes infant deaths under age 7 days and fetal deaths at 28 weeks of gestation or more). Preterm birth is the single most important contributing factor to increased risk of perinatal mortality among ART singletons compared to non-ART singletons. Further research on reducing early preterm delivery, with the aim of reducing the perinatal mortality among ART births is needed. Couples who access ART treatment should be fully informed regarding the risk of preterm birth and subsequent risk of perinatal death. There was no funding associated with this study. No conflict of interest was declared. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

[Fat emulsion tolerance in preterm infants of different gestational ages in the early stage after birth].

PubMed

Tang, Hui; Yang, Chuan-Zhong; Li, Huan; Wen, Wei; Huang, Fang-Fang; Huang, Zhi-Feng; Shi, Yu-Ping; Yu, Yan-Liang; Chen, Li-Lian; Yuan, Rui-Qin; Zhu, Xiao-Yu

2017-06-01

To investigate the fat emulsion tolerance in preterm infants of different gestational ages in the early stage after birth. A total of 98 preterm infants were enrolled and divided into extremely preterm infant group (n=17), early preterm infant group (n=48), and moderate-to-late preterm infant group (n=33). According to the dose of fat emulsion, they were further divided into low- and high-dose subgroups. The umbilical cord blood and dried blood filter papers within 3 days after birth were collected. Tandem mass spectrometry was used to measure the content of short-, medium-, and long-chain acylcarnitines. The extremely preterm infant and early preterm infant groups had a significantly lower content of long-chain acylcarnitines in the umbilical cord blood and dried blood filter papers within 3 days after birth than the moderate-to-late preterm infant group (P<0.05), and the content was positively correlated with gestational age (P<0.01). On the second day after birth, the low-dose fat emulsion subgroup had a significantly higher content of short-, medium-, and long-chain acylcarnitines than the high-dose fat emulsion subgroup among the extremely preterm infants (P<0.05). In the early preterm infant and moderate-to-late preterm infant groups, there were no significant differences in the content of short-, medium-, and long-chain acylcarnitines between the low- and high-dose fat emulsion subgroups within 3 days after birth. Compared with moderate-to-late preterm infants, extremely preterm infants and early preterm infants have a lower capacity to metabolize long-chain fatty acids within 3 days after birth. Early preterm infants and moderate-to-late preterm infants may tolerate high-dose fat emulsion in the early stage after birth, but extremely preterm infants may have an insufficient capacity to metabolize high-dose fat emulsion.

Quantifying the impact of deprivation on preterm births: a retrospective cohort study.

PubMed

Taylor-Robinson, David; Agarwal, Umber; Diggle, Peter J; Platt, Mary Jane; Yoxall, Bill; Alfirevic, Zarko

2011-01-01

Social deprivation is associated with higher rates of preterm birth and subsequent infant mortality. Our objective was to identify risk factors for preterm birth in the UK's largest maternity unit, with a particular focus on social deprivation, and related factors. Retrospective cohort study of 39,873 women in Liverpool, UK, from 2002-2008. Singleton pregnancies were stratified into uncomplicated low risk pregnancies and a high risk group complicated by medical problems. Multiple logistic regression, and generalized additive models were used to explore the effect of covariates including area deprivation, smoking status, BMI, parity and ethnicity on the risk of preterm birth (34⁺⁰ weeks). In the low risk group, preterm birth rates increased with deprivation, reaching 1.6% (CI₉₅ 1.4 to 1.8) in the most deprived quintile; the unadjusted odds ratio comparing an individual in the most deprived quintile, to one in the least deprived quintile was 1.5 (CI₉₅ 1.2 to 1.9). Being underweight and smoking were both independently associated with preterm birth in the low risk group, and adjusting for these factors explained the association between deprivation and preterm birth. Preterm birth was five times more likely in the high risk group (RR 4.8 CI₉₅ 4.3 to 5.4), and there was no significant relationship with deprivation. Deprivation has significant impact on preterm birth rates in low risk women. The relationship between low socio-economic status and preterm births appears to be related to low maternal weight and smoking in more deprived groups.

Low dose aspirin in the prevention of recurrent spontaneous preterm labour - the APRIL study: a multicenter randomized placebo controlled trial.

PubMed

Visser, Laura; de Boer, Marjon A; de Groot, Christianne J M; Nijman, Tobias A J; Hemels, Marieke A C; Bloemenkamp, Kitty W M; Bosmans, Judith E; Kok, Marjolein; van Laar, Judith O; Sueters, Marieke; Scheepers, Hubertina; van Drongelen, Joris; Franssen, Maureen T M; Sikkema, J Marko; Duvekot, Hans J J; Bekker, Mireille N; van der Post, Joris A M; Naaktgeboren, Christiana; Mol, Ben W J; Oudijk, Martijn A

2017-07-14

Preterm birth (birth before 37 weeks of gestation) is a major problem in obstetrics and affects an estimated 15 million pregnancies worldwide annually. A history of previous preterm birth is the strongest risk factor for preterm birth, and recurrent spontaneous preterm birth affects more than 2.5 million pregnancies each year. A recent meta-analysis showed possible benefits of the use of low dose aspirin in the prevention of recurrent spontaneous preterm birth. We will assess the (cost-)effectiveness of low dose aspirin in comparison with placebo in the prevention of recurrent spontaneous preterm birth in a randomized clinical trial. Women with a singleton pregnancy and a history of spontaneous preterm birth in a singleton pregnancy (22-37 weeks of gestation) will be asked to participate in a multicenter, randomized, double blinded, placebo controlled trial. Women will be randomized to low dose aspirin (80 mg once daily) or placebo, initiated from 8 to 16 weeks up to maximal 36 weeks of gestation. The primary outcome measure will be preterm birth, defined as birth at a gestational age (GA) < 37 weeks. Secondary outcomes will be a composite of adverse neonatal outcome and maternal outcomes, including subgroups of prematurity, as well as intrauterine growth restriction (IUGR) and costs from a healthcare perspective. Preterm birth will be analyzed as a group, as well as separately for spontaneous or indicated onset. Analysis will be performed by intention to treat. In total, 406 pregnant women have to be randomized to show a reduction of 35% in preterm birth from 36 to 23%. If aspirin is effective in preventing preterm birth, we expect that there will be cost savings, because of the low costs of aspirin. To evaluate this, a cost-effectiveness analysis will be performed comparing preventive treatment with aspirin with placebo. This trial will provide evidence as to whether or not low dose aspirin is (cost-) effective in reducing recurrence of spontaneous preterm birth. Clinical trial registration number of the Dutch Trial Register: NTR 5675 . EudraCT-registration number: 2015-003220-31.

Early pregnancy vaginal microbiome trends and preterm birth.

PubMed

Stout, Molly J; Zhou, Yanjiao; Wylie, Kristine M; Tarr, Phillip I; Macones, George A; Tuuli, Methodius G

2017-09-01

Despite decades of attempts to link infectious agents to preterm birth, an exact causative microbe or community of microbes remains elusive. Nonculture 16S ribosomal RNA gene sequencing suggests important racial differences and pregnancy specific changes in the vaginal microbial communities. A recent study examining the association of the vaginal microbiome and preterm birth documented important findings but was performed in a predominantly white cohort. Given the important racial differences in bacterial communities within the vagina as well as persistent racial disparities in preterm birth, it is important to examine cohorts with varied demographic compositions. To characterize vaginal microbial community characteristics in a large, predominantly African-American, longitudinal cohort of pregnant women and test whether particular vaginal microbial community characteristics are associated with the risk for subsequent preterm birth. This is a nested case-control study within a prospective cohort study of women with singleton pregnancies, not on supplemental progesterone, and without cervical cerclage in situ. Serial mid-vaginal swabs were obtained by speculum exam at their routine prenatal visits. Sequencing of the V1V3 region of the 16S rRNA gene was performed on the Roche 454 platform. Alpha diversity community characteristics including richness, Shannon diversity, and evenness as well as beta diversity metrics including Bray Curtis Dissimilarity and specific taxon abundance were compared longitudinally in women who delivered preterm to those who delivered at term. A total of 77 subjects contributed 149 vaginal swabs longitudinally across pregnancy. Participants were predominantly African-American (69%) and had a preterm birth rate of 31%. In subjects with subsequent term delivery, the vaginal microbiome demonstrated stable community richness and Shannon diversity, whereas subjects with subsequent preterm delivery had significantly decreased vaginal richness, diversity, and evenness during pregnancy (P < .01). This change occurred between the first and second trimesters. Within-subject comparisons across pregnancy showed that preterm birth is associated with increased vaginal microbiome instability compared to term birth. No distinct taxa were associated with preterm birth. In a predominantly African-American population, a significant decrease of vaginal microbial community richness and diversity is associated with preterm birth. The timing of this suppression appears early in pregnancy, between the first and second trimesters, suggesting that early gestation may be an ecologically important time for events that ordain subsequent term and preterm birth outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

Treatment of vaginal candidiasis for the prevention of preterm birth: a systematic review and meta-analysis.

PubMed

Roberts, Christine L; Algert, Charles S; Rickard, Kristen L; Morris, Jonathan M

2015-03-21

Recognition that ascending infection leads to preterm birth has led to a number of studies that have evaluated the treatment of vaginal infections in pregnancy to reduce preterm birth rates. However, the role of candidiasis is relatively unexplored. Our aim was to undertake a systematic review and meta-analysis to assess whether treatment of pregnant women with vulvovaginal candidiasis reduces preterm birth rates and other adverse birth outcomes. We undertook a systematic review and meta-analysis of published randomised controlled trials (RCTs) in which pregnant women were treated for vulvovaginal candidiasis (compared to placebo or no treatment) and where preterm birth was reported as an outcome. Trials were identified by searching the Cochrane Central Register of Controlled Trials, Medline and Embase databases to January 2014. Trial eligibility and outcomes were pre-specified. Two reviewers independently assessed the studies against the agreed criteria and extracted relevant data using a standard data extraction form. Meta-analysis was used to calculate pooled rate ratios (RR) and 95% confidence intervals (CI) using a fixed-effects model. There were two eligible RCTs both among women with asymptomatic candidiasis, with a total of 685 women randomised. Both trials compared treatment with usual care (no screening for, or treatment of, asymptomatic candidiasis). Data from one trial involved a post-hoc subgroup analysis (n = 586) of a larger trial of treatment of 4,429 women with asymptomatic infections in pregnancy and the other was a pilot study (n = 99). There was a significant reduction in spontaneous preterm births in treated compared with untreated women (meta-analysis RR = 0.36, 95% CI = 0.17 to 0.75). Other outcomes were reported by one or neither trial. This systematic review found two trials comparing the treatment of asymptomatic vaginal candidiasis in pregnancy for the outcome of preterm birth. Although the effect estimate suggests that treatment of asymptomatic candidiasis may reduce the risk of preterm birth, the result needs to be interpreted with caution as the primary driver for the pooled estimate comes from a post-hoc (unplanned) subgroup analysis. A prospective trial with sufficient power to answer the clinical question 'does treatment of asymptomatic candidiasis in early pregnancy prevent preterm birth' is warranted. PROSPERO CRD42014009241.

Economic costs associated with moderate and late preterm birth: a prospective population-based study.

PubMed

Khan, K A; Petrou, S; Dritsaki, M; Johnson, S J; Manktelow, B; Draper, E S; Smith, L K; Seaton, S E; Marlow, N; Dorling, J; Field, D J; Boyle, E M

2015-10-01

We sought to determine the economic costs associated with moderate and late preterm birth. An economic study was nested within a prospective cohort study. Infants born between 32(+0) and 36(+6)  weeks of gestation in the East Midlands of England. A sample of infants born at ≥37 weeks of gestation acted as controls. Data on resource use, estimated from a National Health Service (NHS) and personal social services perspective, and separately from a societal perspective, were collected between birth and 24 months corrected age (or death), and valued in pounds sterling, at 2010-11 prices. Descriptive statistics and multivariable analyses were used to estimate the relationship between gestational age at birth and economic costs. Cumulative resource use and economic costs over the first two years of life. Of all eligible births, 1146 (83%) preterm and 1258 (79%) term infants were recruited. Mean (standard error) total societal costs from birth to 24 months were £12 037 (£1114) and £5823 (£1232) for children born moderately preterm (32(+0) -33(+6)  weeks of gestation) and late preterm (34(+0) -36(+6)  weeks of gestation), respectively, compared with £2056 (£132) for children born at term. The mean societal cost difference between moderate and late preterm and term infants was £4657 (bootstrap 95% confidence interval, 95% CI £2513-6803; P < 0.001). Multivariable regressions revealed that, after controlling for clinical and sociodemographic characteristics, moderate and late preterm birth increased societal costs by £7583 (£874) and £1963 (£337), respectively, compared with birth at full term. Moderate and late preterm birth is associated with significantly increased economic costs over the first 2 years of life. Our economic estimates can be used to inform budgetary and service planning by clinical decision-makers, and economic evaluations of interventions aimed at preventing moderate and late preterm birth or alleviating its adverse consequences. Moderate and late preterm birth is associated with increased economic costs over the first 2 years of life. © 2015 Royal College of Obstetricians and Gynaecologists.

Cumulative psychosocial stress, coping resources, and preterm birth.

PubMed

McDonald, Sheila W; Kingston, Dawn; Bayrampour, Hamideh; Dolan, Siobhan M; Tough, Suzanne C

2014-12-01

Preterm birth constitutes a significant international public health issue, with implications for child and family well-being. High levels of psychosocial stress and negative affect before and during pregnancy are contributing factors to shortened gestation and preterm birth. We developed a cumulative psychosocial stress variable and examined its association with early delivery controlling for known preterm birth risk factors and confounding environmental variables. We further examined this association among subgroups of women with different levels of coping resources. Utilizing the All Our Babies (AOB) study, an ongoing prospective pregnancy cohort study in Alberta, Canada (n = 3,021), multinomial logistic regression was adopted to examine the independent effect of cumulative psychosocial stress and preterm birth subgroups compared to term births. Stratified analyses according to categories of perceived social support and optimism were undertaken to examine differential effects among subgroups of women. Cumulative psychosocial stress was a statistically significant risk factor for late preterm birth (OR = 1.73; 95 % CI = 1.07, 2.81), but not for early preterm birth (OR = 2.44; 95 % CI = 0.95, 6.32), controlling for income, history of preterm birth, pregnancy complications, reproductive history, and smoking in pregnancy. Stratified analyses showed that cumulative psychosocial stress was a significant risk factor for preterm birth at <37 weeks gestation for women with low levels of social support (OR = 2.09; 95 % CI = 1.07, 4.07) or optimism (OR = 1.87; 95 % CI = 1.04, 3.37). Our analyses suggest that early vulnerability combined with current anxiety symptoms in pregnancy confers risk for preterm birth. Coping resources may mitigate the effect of cumulative psychosocial stress on the risk for early delivery.

Comparison of black-white disparities in preterm birth between Canada and the United States.

PubMed

McKinnon, Britt; Yang, Seungmi; Kramer, Michael S; Bushnik, Tracey; Sheppard, Amanda J; Kaufman, Jay S

2016-01-05

A higher risk of preterm birth among black women than among white women is well established in the United States. We compared differences in preterm birth between non-Hispanic black and white women in Canada and the US, hypothesizing that disparities would be less extreme in Canada given the different historical experiences of black populations and Canada's universal health care system. Using data on singleton live births in Canada and the US for 2004-2006, we estimated crude and adjusted risk ratios and risk differences in preterm birth (< 37 wk) and very preterm birth (< 32 wk) among non-Hispanic black versus non-Hispanic white women in each country. Adjusted models for the US were standardized to the covariate distribution of the Canadian cohort. In Canada, 8.9% and 5.9% of infants born to black and white mothers, respectively, were preterm; the corresponding figures in the US were 12.7% and 8.0%. Crude risk ratios for preterm birth among black women relative to white women were 1.49 (95% confidence interval [CI] 1.32 to 1.66) in Canada and 1.57 (95% CI 1.56 to 1.58) in the US (p value for heterogeneity [pH] = 0.3). The crude risk differences for preterm birth were 2.94 (95% CI 1.91 to 3.96) in Canada and 4.63 (95% CI 4.56 to 4.70) in the US (pH = 0.003). Adjusted risk ratios for preterm birth (pH = 0.1) were slightly higher in Canada than in the US, whereas adjusted risk differences were similar in both countries. Similar patterns were observed for racial disparities in very preterm birth. Relative disparities in preterm birth and very preterm birth between non-Hispanic black and white women were similar in magnitude in Canada and the US. Absolute disparities were smaller in Canada, which reflects a lower overall risk of preterm birth in Canada than in the US in both black and white populations. © 2016 Canadian Medical Association or its licensors.

Comparison of black–white disparities in preterm birth between Canada and the United States

PubMed Central

McKinnon, Britt; Yang, Seungmi; Kramer, Michael S.; Bushnik, Tracey; Sheppard, Amanda J.; Kaufman, Jay S.

2016-01-01

Background: A higher risk of preterm birth among black women than among white women is well established in the United States. We compared differences in preterm birth between non-Hispanic black and white women in Canada and the US, hypothesizing that disparities would be less extreme in Canada given the different historical experiences of black populations and Canada’s universal health care system. Methods: Using data on singleton live births in Canada and the US for 2004–2006, we estimated crude and adjusted risk ratios and risk differences in preterm birth (< 37 wk) and very preterm birth (< 32 wk) among non-Hispanic black versus non-Hispanic white women in each country. Adjusted models for the US were standardized to the covariate distribution of the Canadian cohort. Results: In Canada, 8.9% and 5.9% of infants born to black and white mothers, respectively, were preterm; the corresponding figures in the US were 12.7% and 8.0%. Crude risk ratios for preterm birth among black women relative to white women were 1.49 (95% confidence interval [CI] 1.32 to 1.66) in Canada and 1.57 (95% CI 1.56 to 1.58) in the US (p value for heterogeneity [pH] = 0.3). The crude risk differences for preterm birth were 2.94 (95% CI 1.91 to 3.96) in Canada and 4.63 (95% CI 4.56 to 4.70) in the US (pH = 0.003). Adjusted risk ratios for preterm birth (pH = 0.1) were slightly higher in Canada than in the US, whereas adjusted risk differences were similar in both countries. Similar patterns were observed for racial disparities in very preterm birth. Interpretation: Relative disparities in preterm birth and very preterm birth between non-Hispanic black and white women were similar in magnitude in Canada and the US. Absolute disparities were smaller in Canada, which reflects a lower overall risk of preterm birth in Canada than in the US in both black and white populations. PMID:26553860

The Association Between Diabetes Mellitus Among American Indian/Alaska Native Populations with Preterm Birth in Eight US States from 2004-2011.

PubMed

Dorfman, Haley; Srinath, Meghna; Rockhill, Karilynn; Hogue, Carol

2015-11-01

Assess risk of preterm birth associated with diabetes mellitus (DM) among American Indian and Alaska Natives (AI/AN), a population with increased risk of DM and preterm birth, and examine whether this association differed by state of residence. We used surveillance data from the Pregnancy Risk Assessment Monitoring System from 12,400 AI/AN respondents with singleton births in Alaska, Minnesota, Nebraska, New Mexico, Oklahoma, Oregon, Utah, and Washington from 2004-2011. We conducted multivariable logistic regression models to estimate the odds ratio adjusted for maternal age and prepregnancy BMI with all observations and then stratified by state. DM was reported in 5.92 % of the study population and preterm birth occurred in 8.95 % of births. Women with DM had 1.92 times higher odds of having a preterm birth than women without DM [95 % confidence interval (CI) 1.21-2.78]. After stratifying on state, women with DM in Nebraska had the greatest odds of preterm birth [aOR 6.63, (95 % CI 3.80-11.6)] while women in Alaska saw a protective effect from DM [aOR 0.17, (95 % CI 0.07-0.42)] compared to women without DM. Overall, AI/AN women with DM had significantly greater odds of preterm birth compared to AI/AN women without DM across states. Substantial differences in this association between states calls for increased public health efforts in high-risk areas as well as further research to assess whether differences are attributable to diagnosis, reporting, tribal, healthcare or lifestyle factors.

The interaction between maternal race/ethnicity and chronic hypertension on preterm birth.

PubMed

Premkumar, Ashish; Henry, Dana E; Moghadassi, Michelle; Nakagawa, Sanae; Norton, Mary E

2016-12-01

In both the biomedical and public health literature, the risk for preterm birth has been linked to maternal racial/ethnic background, in particular African-American heritage. Despite this well-documented health disparity, the relationship of comorbid conditions, such as chronic hypertension, to maternal race/ethnicity and preterm birth has received relatively limited attention in the literature. The objective of the study was to evaluate the interaction between chronic hypertension and maternal racial/ethnic background on preterm birth. This is a retrospective cohort study of singleton pregnancies among women who delivered between 2002 and 2015 at the University of California, San Francisco. The associations of chronic hypertension with both spontaneous and medically indicated preterm birth were examined by univariate and multivariate logistical regression, adjusting for confounders including for maternal age, history of preterm birth, maternal body mass index, insurance type (public vs private), smoking, substance abuse, history of pregestational diabetes mellitus, and use of assisted reproductive technologies. The interaction effect of chronic hypertension and racial/ethnicity was also evaluated. All values are reported as odds ratios, with 95% confidence intervals and significance set at P = .05. In this cohort of 23,425 singleton pregnancies, 8.8% had preterm deliveries (3% were medically indicated preterm birth, whereas 5.5% were spontaneous preterm births), and 3.8% of women carried the diagnosis of chronic hypertension. Chronic hypertension was significantly associated with preterm birth in general (adjusted odds ratio, 2.74, P < .001) and medically indicated preterm birth specifically (adjusted odds ratio, 5.25, P < .001). When evaluating the effect of chronic hypertension within racial/ethnic groups, there was an increased odds of a preterm birth among hypertensive, African-American women (adjusted odds ratio, 3.91, P < .001) and hypertensive, Asian-American/Pacific Islander women (adjusted odds ratio, 3.51, P < .001) when compared with their nonhypertensive counterparts within the same racial/ethnic group. These significant effects were also noted with regard to medically indicated preterm birth for hypertensive African-American women (adjusted odds ratio, 6.85, P < .001) and Asian-American/Pacific Islander women (adjusted odds ratio, 9.87, P < .001). There was no significant association of chronic hypertension with spontaneous preterm birth (adjusted odds ratio, 0.87, P = .4). The effect of chronic hypertension on overall preterm birth and medically indicated preterm birth differs by racial/ethnic group. The larger effect of chronic hypertension among African-American and Asian/Pacific Islander women on medically indicated and total preterm birth rates raises the possibility of an independent variable that is not captured in the data analysis, although data regarding the indication for medically indicated preterm delivery was limited in this data set. Further investigation into both social-structural and biological predispositions to preterm birth should accompany research focusing on the effect of chronic hypertension on birth outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

Longitudinal profiling of inflammatory cytokines and C-reactive protein during uncomplicated and preterm pregnancy.

PubMed

Ferguson, Kelly K; McElrath, Thomas F; Chen, Yin-Hsiu; Mukherjee, Bhramar; Meeker, John D

2014-09-01

Previous studies have investigated the utility of inflammation markers as predictors of preterm birth, but none have compared trends in levels between uncomplicated and preterm pregnancy. We explored longitudinal changes in plasma cytokines, including IL-1β, IL-6, IL-10, and TNF-α, as well as C-reactive protein in pregnant women from a nested case-control study. IL-6 was associated with increased odds of spontaneous preterm birth, defined by presentation of spontaneous preterm labor and/or preterm premature rupture of the membranes. Associations were strongest later in pregnancy. IL-10 was associated with increased odds of placentally mediated preterm birth, defined by presentation with preeclampsia or intrauterine growth restriction, and odds ratios were also highest near the end of pregnancy. Maternal inflammation markers were associated with increased risk of preterm birth, and relationships differed by etiology of preterm delivery and gestational age at sample collection. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Trends in preterm birth: singleton and multiple pregnancies in the Netherlands, 2000-2007.

PubMed

Schaaf, J M; Mol, B W J; Abu-Hanna, A; Ravelli, A C J

2011-09-01

Several studies have reported increasing trends in preterm birth in developed countries, mainly attributable to an increase in medically indicated preterm births. Our aim was to describe trends in preterm birth among singleton and multiple pregnancies in the Netherlands. Prospective cohort study. Nationwide study. We studied 1,451,246 pregnant women from 2000 to 2007. We assessed trends in preterm birth. We subdivided preterm birth into spontaneous preterm birth after premature prelabour rupture of membranes (pPROM), medically indicated preterm birth and spontaneous preterm birth without pPROM. We performed analyses separately for singletons and multiples. The primary outcome was preterm birth, defined as birth before 37 weeks of gestation, with very preterm birth (<32 weeks of gestation) being a secondary outcome. The risk of preterm birth was 7.7% and the risk of very preterm birth was 1.3%. In singleton pregnancies, the preterm birth risk decreased significantly from 6.4% to 6.0% (P < 0.0001), mainly as a result of the decrease in spontaneous preterm birth without pPROM (3.6-3.1%, P < 0.0001). In multiple pregnancies, the preterm birth risk increased significantly (47.3-47.7%, P = 0.047), mainly as a result of medically indicated preterm birth, which increased from 15.0% to 17.9% (P < 0.0001). In the Netherlands, the preterm birth risk in singleton pregnancies decreased significantly over the years. The trend of increasing preterm birth risk reported in other countries was only observed in (medically indicated) preterm birth in multiple pregnancies. © 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG.

Biological determinants of spontaneous late preterm and early term birth: a retrospective cohort study.

PubMed

Brown, H K; Speechley, K N; Macnab, J; Natale, R; Campbell, M K

2015-03-01

Our aim was to examine the association between biological determinants of preterm birth (infection and inflammation, placental ischaemia and other hypoxia, diabetes mellitus, other) and spontaneous late preterm (34-36 weeks) and early term (37-38 weeks) birth. Retrospective cohort study. City of London and Middlesex County, Canada. Singleton live births, delivered at 34-41 weeks to London-Middlesex mothers following spontaneous labour. Data were obtained from a city-wide perinatal database on births between 2002 and 2011 (n = 17,678). Multivariable analyses used multinomial logistic regression. The outcome of interest was the occurrence of late preterm (34-36 weeks) and early term (37-38 weeks) birth, compared with full term birth (39-41 weeks). After controlling for covariates, there were associations between infection and inflammation and late preterm birth (aOR = 2.07, 95% CI 1.65, 2.60); between placental ischaemia and other hypoxia and late preterm (aOR = 2.21, 95% CI 1.88, 2.61) and early term (aOR = 1.25, 95% CI 1.13, 1.39) birth; between diabetes mellitus and late preterm (aOR = 3.89, 95% CI 2.90, 5.21) and early term (aOR = 2.66, 95% CI 2.19, 3.23) birth; and between other biological determinants (polyhydramnios, oligohydramnios) and late preterm (aOR = 2.81, 95% CI 1.70, 4.64) and early term (aOR = 1.89, 95% CI 1.32, 2.70) birth. Our findings show that delivery following spontaneous labour even close to full term may be a result of pathological processes. Because these biological determinants of preterm birth contribute to an adverse intrauterine environment, they have important implications for fetal and neonatal health. © 2014 Royal College of Obstetricians and Gynaecologists.

Outdoor air pollution, preterm birth, and low birth weight: analysis of the world health organization global survey on maternal and perinatal health.

PubMed

Fleischer, Nancy L; Merialdi, Mario; van Donkelaar, Aaron; Vadillo-Ortega, Felipe; Martin, Randall V; Betran, Ana Pilar; Souza, João Paulo

2014-04-01

Inhaling fine particles (particulate matter with diameter ≤ 2.5 μm; PM2.5) can induce oxidative stress and inflammation, and may contribute to onset of preterm labor and other adverse perinatal outcomes. We examined whether outdoor PM2.5 was associated with adverse birth outcomes among 22 countries in the World Health Organization Global Survey on Maternal and Perinatal Health from 2004 through 2008. Long-term average (2001-2006) estimates of outdoor PM2.5 were assigned to 50-km-radius circular buffers around each health clinic where births occurred. We used generalized estimating equations to determine associations between clinic-level PM2.5 levels and preterm birth and low birth weight at the individual level, adjusting for seasonality and potential confounders at individual, clinic, and country levels. Country-specific associations were also investigated. Across all countries, adjusting for seasonality, PM2.5 was not associated with preterm birth, but was associated with low birth weight [odds ratio (OR) = 1.22; 95% CI: 1.07, 1.39 for fourth quartile of PM2.5 (> 20.2 μg/m3) compared with the first quartile (< 6.3 μg/m3)]. In China, the country with the largest PM2.5 range, preterm birth and low birth weight both were associated with the highest quartile of PM2.5 only, which suggests a possible threshold effect (OR = 2.54; CI: 1.42, 4.55 and OR = 1.99; CI: 1.06, 3.72 for preterm birth and low birth weight, respectively, for PM2.5 ≥ 36.5 μg/m3 compared with PM2.5 < 12.5 μg/m3). Outdoor PM2.5 concentrations were associated with low birth weight but not preterm birth. In rapidly developing countries, such as China, the highest levels of air pollution may be of concern for both outcomes.

Does assisted reproduction technology, per se, increase the risk of preterm birth?

PubMed

Blickstein, I

2006-12-01

There is little doubt that all methods of assisted reproduction increase the likelihood of multiple pregnancy and, as a result, increase the likelihood of preterm birth. Data from the East Flanders Prospective Twin Study clearly show that the proportion of spontaneous to iatrogenic twins has changed from 25:1 to 1:1 over the past two decades. Data from the very low birthweight (VLBW) Infant Database of the Israel Neonatal Network showed that 10% of VLBW singletons were a result of assisted reproduction compared with 60% of the VLBW twins and 90% of the VLBW triplets. Irrespective of plurality, an association between preterm birth and assisted reproduction has long been suspected and was related to causes such as iatrogenic preterm birth (in the so-called 'premium' pregnancies), fertility history, past obstetric performance and to underlying medical conditions of the female partner. With more data available, a clearer picture is defined. Two different, recent meta-analyses showed that singleton pregnancies resulting from in vitro fertilisation (IVF) have increased rates of preterm birth at <33 weeks of gestation (OR 2.99; 95% CI 1.54-5.80), at <37 weeks of gestation (OR 1.93; 95% CI 1.36-2.74) and a relative risk of 1.98 (95% CI 1.77-2.22) for preterm birth in singleton pregnancies resulting from in vitro fertilisation embryo transfer/gamete intra fallopian transfer (IVF-ET/GIFT) compared with naturally conceived pregnancies. Since there is no way to predict which pregnant woman is at increased risk of preterm birth, it may be advisable to consider all pregnancies after assisted reproduction as being at risk. In any case, the most appropriate endpoint after assisted reproduction should also include preterm or term birth as measure of success.

Stem-Like Cell Characteristics from Breast Milk of Mothers with Preterm Infants as Compared to Mothers with Term Infants.

PubMed

Briere, Carrie-Ellen; Jensen, Todd; McGrath, Jacqueline M; Young, Erin E; Finck, Christine

2017-04-01

Breast milk stem cells are hypothesized to be involved in infant health and development. Our research team is the first known team to enroll mothers of hospitalized preterm infants during the first few weeks of lactation and compare stem cell phenotypes and gene expression to mothers of healthy full-term infants. Participants were recruited from a Level IV Neonatal Intensive Care Unit (preterm dyads) and the community (full-term dyads) in the northeastern United States. Mothers of hospitalized preterm infants (<37 weeks gestational age at birth) and mothers of healthy full-term infants (>39 weeks gestational age at birth). Breast milk stem-like cell populations were identified in both preterm and full-term breast milk samples. The data suggest variability in the proportion of stem cell phenotypes present, as well as statistically significant differential expression (both over- and underexpression) of stem cell-specific genetic markers when comparing mothers' milk for preterm and full-term births. Our findings indicate that (1) stem cells are present in preterm breast milk; (2) differential expression of stem cell-specific markers can be detected in preterm and full-term breast milk samples; and (3) the percentage of cells expressing the various stem cell-specific markers differs when preterm and full-term breast milk samples are compared.

Reproductive outcomes following induced abortion: a national register-based cohort study in Scotland.

PubMed

Bhattacharya, Siladitya; Lowit, Alison; Bhattacharya, Sohinee; Raja, Edwin Amalraj; Lee, Amanda Jane; Mahmood, Tahir; Templeton, Allan

2012-01-01

To investigate reproductive outcomes in women following induced abortion (IA). Retrospective cohort study. Hospital admissions between 1981 and 2007 in Scotland. Data were extracted on all women who had an IA, a miscarriage or a live birth from the Scottish Morbidity Records. A total of 120 033, 457 477 and 47 355 women with a documented second pregnancy following an IA, live birth and miscarriage, respectively, were identified. Obstetric and perinatal outcomes, especially preterm delivery in a second ongoing pregnancy following an IA, were compared with those in primigravidae, as well as those who had a miscarriage or live birth in their first pregnancy. Outcomes after surgical and medical termination as well as after one or more consecutive IAs were compared. IA in a first pregnancy increased the risk of spontaneous preterm birth compared with that in primigravidae (adjusted RR (adj. RR) 1.37, 95% CI 1.32 to 1.42) or women with an initial live birth (adj. RR 1.66, 95% CI 1.58 to 1.74) but not in comparison with women with a previous miscarriage (adj. RR 0.85, 95% CI 0.79 to 0.91). Surgical abortion increased the risk of spontaneous preterm birth compared with medical abortion (adj. RR 1.25, 95% CI 1.07 to 1.45). The adjusted RRs (95% CI) for spontaneous preterm delivery following two, three and four consecutive IAs were 0.94 (0.81 to 1.10), 1.06 (0.76 to 1.47) and 0.92 (0.53 to 1.61), respectively. The risk of preterm birth after IA is lower than that after miscarriage but higher than that in a first pregnancy or after a previous live birth. This risk is not increased further in women who undergo two or more consecutive IAs. Surgical abortion appears to be associated with an increased risk of spontaneous preterm birth in comparison with medical termination of pregnancy. Medical termination was not associated with an increased risk of preterm delivery compared to primigravidae.

Relationships among neighborhood environment, racial discrimination, psychological distress, and preterm birth in African American women.

PubMed

Giurgescu, Carmen; Zenk, Shannon N; Dancy, Barbara L; Park, Chang G; Dieber, William; Block, Richard

2012-01-01

To (a) examine the relationships among objective and perceived indicators of neighborhood environment, racial discrimination, psychological distress, and gestational age at birth; (b) determine if neighborhood environment and racial discrimination predicted psychological distress; (c) determine if neighborhood environment, racial discrimination, and psychological distress predicted preterm birth; and (d) determine if psychological distress mediated the effects of neighborhood environment and racial discrimination on preterm birth. Descriptive correlational comparative. Postpartum unit of a medical center in Chicago. African American women (n(1)  = 33 with preterm birth; n(2)  = 39 with full-term birth). Women completed the instruments 24 to 72 hours after birth. Objective measures of the neighborhood were derived using geographic information systems (GIS). Women who reported higher levels of perceived social and physical disorder and perceived crime also reported higher levels of psychological distress. Women who reported more experiences of racial discrimination also had higher levels of psychological distress. Objective social disorder and perceived crime predicted psychological distress. Objective physical disorder and psychological distress predicted preterm birth. Psychological distress mediated the effect of objective social disorder and perceived crime on preterm birth. Women's neighborhood environments and racial discrimination were related to psychological distress, and these factors may increase the risk for preterm birth. © 2012 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

Comparison of two measures of gestational age among low income births. The potential impact on health studies, New York, 2005.

PubMed

Lazariu, Victoria; Davis, Christopher F; McNutt, Louise-Anne

2013-01-01

Recently, the National Association for Public Health Statistics and Information Systems considered changing the definition of gestational age from the current definition based on mother's last normal menstrual period (LMP) to the clinical/obstetric estimate determined by the physician (CE).They determined additional information was needed. This study provides additional insight into the comparability of the LMP and CE measures currently used on vital records among births at risk for poor outcomes. The data consisted of all New York State (NYS) (excluding New York City) singleton births in 2005 among mothers enrolled in the NYS Women Infants and Children (WIC) program during pregnancy. Prenatal WIC records were matched to NYS' Statewide Perinatal Data System. The analysis investigates differences between LMP and CE recorded gestations. Relative risks between risk factors and preterm birth were compared for LMP and CE. Exact agreement between gestation measures exists in 49.6% of births. Overall, 6.4% of records indicate discordance in full term/preterm classifications; CE is full term and LMP preterm in 4.9%, with the converse true for 1.5%. Associations between risk factor and preterm birth differed in magnitude based on gestational age measurement. Infants born to mothers with high risk indicators were more likely to have a CE of preterm and LMP full term. Changing the measure of gestational age to CE universally likely would result in overestimation of the importance of some risk factors for preterm birth. Potential overestimation of clinical outcomes associated with preterm birth may occur and should be studied.

The More, the Better? Combining Interventions to Prevent Preterm Birth in Women at Risk: a Systematic Review and Meta-Analysis.

PubMed

Jarde, Alexander; Lewis-Mikhael, Anne-Mary; Dodd, Jodie M; Barrett, Jon; Saito, Shigeru; Beyene, Joseph; McDonald, Sarah D

2017-12-01

To systematically examine the evidence around the combination of interventions to prevent preterm birth. Without language restrictions, we searched clinicaltrials.gov and five electronic databases (Medline, EMBASE, CINAHL, Cochrane CENTRAL, and Web of Science) up to July 7, 2016. We included randomized and non-randomized studies where asymptomatic women at risk of preterm birth received any combination of progesterone, cerclage, or pessary compared with either one or no intervention. Primary outcomes were preterm birth <34 and <37 weeks and neonatal death. Two independent reviewers extracted data using a piloted form and assessed risk and direction of bias. We pooled data with unlikely or unclear bias using random-effects meta-analyses. Comparisons with likely bias (e.g., confounding by indication) were not pooled. We screened 1335 results and assessed 154 full texts, including seven studies. In singletons, we found no differences in preterm birth <34 weeks when comparing pessary & progesterone with pessary alone (RR 1.30, 95% CI 0.70-2.42) or progesterone alone (RR 1.16, 95% CI 0.79-1.72). Similarly, we found no differences in preterm birth <37 weeks when comparing cerclage & progesterone with cerclage alone (RR 1.04, 95% CI 0.56-1.93) or with progesterone alone (RR 0.82, 95% CI 0.57-1.19) nor between pessary & progesterone and pessary alone (RR 1.04, 95% CI 0.62-1.74). No data were available for neonatal death in singletons. Despite being a common clinical practice, evidence to support the combined use of multiple versus single interventions for preventing preterm birth is scarce. Copyright © 2017 Society of Obstetricians and Gynaecologists of Canada. Published by Elsevier Inc. All rights reserved.

The incidence of histological chorioamnionitis in IVF/GIFT preterm births.

PubMed

Williams, H; Jeffery, H

1994-08-01

A retrospective case control study was designed to investigate the role of subclinical infection as a risk factor for the high rate of preterm deliveries in IVF/GIFT pregnancies. The cases and the controls were identified from the records of consecutive livebirths of < 35 weeks' gestational age (GA), at King George V Hospital from 1987-1993. Fifty one singleton and 58 twin IVF/GIFT preterm births were matched for GA, year of birth, plurality, maternal age, parity, preclampsia and antepartum haemorrhage. As a marker of subclinical infection, the incidence of histological chorioamnionitis (HCA) in the 2 groups (as defined by the standardized, semiquantitative method of Benirschke) was compared. The matched variables did not differ significantly between the IVF/GIFT group and the control group. No significant difference in the incidence of HCA was detected between IVF/GIFT and control groups for singletons or twins. Overall 24% of IVF/GIFT and 30% of controls showed evidence of HCA, odds ratio (95% confidence intervals), 0.72 (0.40-1.31). This study showed no evidence that the incidence of HCA, is significantly increased in IVF/GIFT preterm births compared with other matched, preterm births. Therefore, we conclude that subclinical infection/inflammation cannot explain the 4-fold increase in preterm births in the IVF/GIFT population.

Uterine deletion of Trp53 compromises antioxidant responses in mouse decidua

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burnum, Kristin E.; Hirota, Yasushi; Baker, Erin Shammel

2012-09-01

Preterm birth is a global health issue impacting both mothers and children. However, the etiology of preterm birth is not clearly understood. From our recent finding that premature decidual senescence with terminal differentiation is a cause of preterm birth in mice with uterine Trp53 deletion, encoding p53 protein, led us to explore other potential factors that are related to preterm birth. Utilizing proteomics approaches, here we show that 183 candidate proteins cause significant changes in decidua with Trp53 deletion as compared to normal decidua. Functional categorization of these proteins unveiled new pathways that are influenced by p53. In particular, downregulationmore » of a cluster of antioxidant proteins in p53 deficient decidua suggests that increased oxidative stress could be one cause of preterm birth in mice with uterine deletion of Trp53.« less

What have we learned about vaginal infections and preterm birth?

PubMed

Carey, J Christopher; Klebanoff, Mark A

2003-06-01

Asymptomatic maternal genital tract infection during pregnancy, particularly bacterial vaginosis, has been consistently associated with preterm birth. In response to this evidence, the Maternal-Fetal Medicine Units Network (MFMU) designed and conducted 2 large randomized, placebo-controlled clinical trials of metronidazole treatment of asymptomatic pregnant women with bacterial vaginosis or trichomoniasis in a general obstetrical population. These studies showed that treatment of women with bacterial vaginosis failed to prevent preterm birth, regardless of their history of prior preterm birth. Metronidazole treatment of women with trichomoniasis significantly increased the risk of preterm birth compared to placebo. These results formed the basis of the US Preventive Services Task Force recommendation that screening for bacterial vaginosis not be undertaken in low-risk pregnant women, and show that MFMU network studies can have a direct and immediate impact on obstetrical practice.

Uterine Deletion of Trp53 Compromises Antioxidant Responses in the Mouse Decidua

PubMed Central

Burnum, Kristin E.; Hirota, Yasushi; Baker, Erin S.; Yoshie, Mikihiro; Ibrahim, Yehia M.; Monroe, Matthew E.; Anderson, Gordon A.; Smith, Richard D.; Daikoku, Takiko

2012-01-01

Preterm birth is a global health issue impacting millions of mothers and babies. However, the etiology of preterm birth is not clearly understood. Our recent finding that premature decidual senescence with terminal differentiation is a cause of preterm birth in mice with uterine Trp53 deletion, encoding p53 protein, led us to explore other potential factors that are related to preterm birth. Using proteomics approaches, here, we show that 183 candidate proteins show significant changes in deciduae with Trp53 deletion as compared with normal deciduae. Functional categorization of these proteins unveiled new pathways that are influenced by p53. In particular, down-regulation of a cluster of antioxidant enzymes in p53-deficient deciduae suggests that increased oxidative stress could be one cause of preterm birth in mice harboring uterine deletion of Trp53. PMID:22759378

Provider-Initiated Late Preterm Births in Brazil: Differences between Public and Private Health Services

PubMed Central

Leal, Maria do Carmo; Esteves-Pereira, Ana Paula; Nakamura-Pereira, Marcos; Torres, Jacqueline Alves; Domingues, Rosa Maria Soares Madeira; Dias, Marcos Augusto Bastos; Moreira, Maria Elizabeth; Theme-Filha, Mariza; da Gama, Silvana Granado Nogueira

2016-01-01

Background A large proportion of the rise in prematurity worldwide is owing to late preterm births, which may be due to the expansion of obstetric interventions, especially pre-labour caesarean section. Late preterm births pose similar risks to overall prematurity, making this trend a concern. In this study, we describe factors associated with provider-initiated late preterm birth and verify differences in provider-initiated late preterm birth rates between public and private health services according to obstetric risk. Methods This is a sub-analysis of a national population-based survey of postpartum women entitled “Birth in Brazil”, performed between 2011 and 2012. We included 23,472 singleton live births. We performed non-conditional multiple logistic regressions assessing associated factors and analysing differences between public and private health services. Results Provider-initiated births accounted for 38% of late preterm births; 32% in public health services and 61% in private health services. They were associated with previous preterm birth(s) and maternal pathologies for women receiving both public and private services and with maternal age ≥35 years for women receiving public services. Women receiving private health services had higher rates of provider-initiated late preterm birth (rate of 4.8%) when compared to the ones receiving public services (rate of 2.4%), regardless of obstetric risk–adjusted OR of 2.3 (CI 1.5–3.6) for women of low obstetric risk and adjusted OR of 1.6 (CI 1.1–2.3) for women of high obstetric risk. Conclusion The high rates of provider-initiated late preterm birth suggests a considerable potential for reduction, as such prematurity can be avoided, especially in women of low obstetric risk. To promote healthy births, we advise introducing policies with incentives for the adoption of new models of birth care. PMID:27196102

The diagnosis and natural history of false preterm labor.

PubMed

Chao, Tamara T; Bloom, Steven L; Mitchell, Judith S; McIntire, Donald D; Leveno, Kenneth J

2011-12-01

To estimate the natural history of pregnancies in women who present with preterm labor symptoms and who are sent home with a diagnosis of false labor. A prospective observational study of women with singletons and intact membranes who presented to triage between 24 0/7 and 33 6/7 weeks of gestation with preterm labor symptoms and cervical dilation less than 2 cm was conducted. Women sent home with a diagnosis of false preterm labor were analyzed against a comparable general obstetric population delivered during the same time period. The primary outcome was delivery before 37 weeks of gestation. Secondary outcomes included the interval between presentation and delivery, as well as maternal and neonatal outcomes. Of the 843 women who met inclusion criteria, 690 (82%) were sent home with a diagnosis of false preterm labor and 153 (18%) were admitted to labor and delivery. When analyzed compared with a comparable general obstetric population, women sent home had a similar rate of birth before 34 weeks of gestation (2% compared with 1%, P=.28) but a higher rate of birth between 34 and 36 weeks of gestation (5% compared with 2%, P<.001). There was no difference in neonatal mortality (0% compared with 0.3%, P=.18). Women with cervical dilation of 1 cm at discharge were more likely to deliver before 34 weeks of gestation compared with nondilated women (5% compared with 1%, P=.02); however, 89% of the 1-cm group delivered more than 21 days after presentation. Women sent home with a diagnosis of false preterm labor are not at increased risk for early preterm birth or neonatal mortality; however, they are at increased risk for late preterm birth. II.

Changes in Neuroactive Steroid Concentrations After Preterm Delivery in the Guinea Pig

PubMed Central

Hirst, Jonathan J.; Palliser, Hannah K.

2013-01-01

Background: Preterm birth is a major cause of neurodevelopmental disorders. Allopregnanolone, a key metabolite of progesterone, has neuroprotective and developmental effects in the brain. The objectives of this study were to measure the neuroactive steroid concentrations following preterm delivery in a neonatal guinea pig model and assess the potential for postnatal progesterone replacement therapy to affect neuroactive steroid brain and plasma concentrations in preterm neonates. Methods: Preterm (62-63 days) and term (69 days) guinea pig pups were delivered by cesarean section and tissue was collected at 24 hours. Plasma progesterone, cortisol, allopregnanolone, and brain allopregnanolone concentrations were measured by immunoassay. Brain 5α-reductase (5αR) expression was determined by Western blot. Neurodevelopmental maturity of preterm neonates was assessed by immunohistochemistry staining for myelination, glial cells, and neurons. Results: Brain allopregnanolone concentrations were significantly reduced after birth in both preterm and term neonates. Postnatal progesterone treatment in preterm neonates increased brain and plasma allopregnanolone concentrations. Preterm neonates had reduced myelination, low birth weight, and high mortality compared to term neonates. Brain 5αR expression was also significantly reduced in neonates compared to fetal expression. Conclusions: Delivery results in a loss of neuroactive steroid concentrations resulting in a premature reduction in brain allopregnanolone in preterm neonates. Postnatal progesterone therapy reestablished neuroactive steroid levels in preterm brains, a finding that has implications for postnatal growth following preterm birth that occurs at a time of neurodevelopmental immaturity. PMID:23585339

Trends in preterm birth and perinatal mortality among singletons: United States, 1989 through 2000.

PubMed

Ananth, Cande V; Joseph, K S; Oyelese, Yinka; Demissie, Kitaw; Vintzileos, Anthony M

2005-05-01

Despite the recent increase in preterm birth in the United States, trends in preterm birth subtypes have not been adequately examined. We examined trends in preterm birth among singletons following ruptured membranes, medical indications, and spontaneous preterm birth and evaluated the impact of these trends on perinatal mortality. A population-based, retrospective cohort study comprising 46,375,578 women (16% blacks) who delivered singleton births in the United States, 1989 through 2000, was performed. Rates of preterm birth (< 37 weeks), their subtypes, and associated perinatal mortality (stillbirths at >/= 22 weeks plus neonatal deaths within 28 days), before and after adjustment for potential confounders, were derived from ecological logistic regression models. Preterm birth rates increased by 14% (95% confidence interval 13-15%) among whites from 8.3% to 9.4% and decreased by 15% (95% confidence interval 14-16%) among blacks from 18.5% to 16.2% between 1989 and 2000. Among whites, preterm birth following ruptured membranes declined by 23%, medically indicated preterm birth increased by 55%, and spontaneous preterm birth increased by 3%. Among blacks, preterm birth following ruptured membranes declined by 37%, medically indicated preterm birth increased by 32%, and spontaneous preterm birth decreased by 27%. The largest decline in perinatal mortality among whites was associated with increases in medically indicated preterm birth, whereas the largest decline in perinatal mortality among blacks was associated with declines in preterm birth following ruptured membranes and spontaneous preterm birth. Temporal trends in preterm birth varied substantially based on underlying subtype and maternal race. The recent increase in medically indicated preterm birth was associated with a favorable reduction in perinatal mortality.

Atrazine exposure in public drinking water and preterm birth.

PubMed

Rinsky, Jessica L; Hopenhayn, Claudia; Golla, Vijay; Browning, Steve; Bush, Heather M

2012-01-01

Approximately 13% of all births occur prior to 37 weeks gestation in the U.S. Some established risk factors exist for preterm birth, but the etiology remains largely unknown. Recent studies have suggested an association with environmental exposures. We examined the relationship between preterm birth and exposure to a commonly used herbicide, atrazine, in drinking water. We reviewed Kentucky birth certificate data for 2004-2006 to collect duration of pregnancy and other individual-level covariates. We assessed existing data sources for atrazine levels in public drinking water for the years 2000-2008, classifying maternal county of residence into three atrazine exposure groups. We used logistic regression to analyze the relationship between atrazine exposure and preterm birth, controlling for maternal age, race/ethnicity, education, smoking, and prenatal care. An increase in the odds of preterm birth was found for women residing in the counties included in the highest atrazine exposure group compared with women residing in counties in the lowest exposure group, while controlling for covariates. Analyses using the three exposure assessment approaches produced odds ratios ranging from 1.20 (95% confidence interval [CI] 1.14, 1.27) to 1.26 (95% CI 1.19, 1.32), for the highest compared with the lowest exposure group. Suboptimal characterization of environmental exposure and variables of interest limited the analytical options of this study. Still, our findings suggest a positive association between atrazine and preterm birth, and illustrate the need for an improved assessment of environmental exposures to accurately address this important public health issue.

Analysis of epigenetic changes in survivors of preterm birth reveals the effect of gestational age and evidence for a long term legacy

PubMed Central

2013-01-01

Background Preterm birth confers a high risk of adverse long term health outcomes for survivors, yet the underlying molecular mechanisms are unclear. We hypothesized that effects of preterm birth can be mediated through measurable epigenomic changes throughout development. We therefore used a longitudinal birth cohort to measure the epigenetic mark of DNA methylation at birth and 18 years comparing survivors of extremely preterm birth with infants born at term. Methods Using 12 extreme preterm birth cases and 12 matched, term controls, we extracted DNA from archived neonatal blood spots and blood collected in a similar way at 18 years of age. DNA methylation was measured at 347,789 autosomal locations throughout the genome using Infinium HM450 arrays. Representative methylation differences were confirmed by Sequenom MassArray EpiTYPER. Results At birth we found 1,555 sites with significant differences in methylation between term and preterm babies. At 18 years of age, these differences had largely resolved, suggesting that DNA methylation differences at birth are mainly driven by factors relating to gestational age, such as cell composition and/or maturity. Using matched longitudinal samples, we found evidence for an epigenetic legacy associated with preterm birth, identifying persistent methylation differences at ten genomic loci. Longitudinal comparisons of DNA methylation at birth and 18 years uncovered a significant overlap between sites that were differentially-methylated at birth and those that changed with age. However, we note that overlapping sites may either differ in the same (300/1,555) or opposite (431/1,555) direction during gestation and aging respectively. Conclusions We present evidence for widespread methylation differences between extreme preterm and term infants at birth that are largely resolved by 18 years of age. These results are consistent with methylation changes associated with blood cell development, cellular composition, immune induction and age at these time points. Finally, we identified ten probes significantly associated with preterm individuals and with greater than 5% methylation discordance at birth and 18 years that may reflect a long term epigenetic legacy of preterm birth. PMID:24134860

Advanced Maternal Age and the Risk of Low Birth Weight and Preterm Delivery: a Within-Family Analysis Using Finnish Population Registers

PubMed Central

Goisis, Alice; Remes, Hanna; Barclay, Kieron; Martikainen, Pekka; Myrskylä, Mikko

2017-01-01

Abstract Advanced maternal age at birth is considered a major risk factor for birth outcomes. It is unclear to what extent this association is confounded by maternal characteristics. To test whether advanced maternal age at birth independently increases the risk of low birth weight (<2,500 g) and preterm birth (<37 weeks’ gestation), we compared between-family models (children born to different mothers at different ages) with within-family models (children born to the same mother at different ages). The latter procedure reduces confounding by unobserved parental characteristics that are shared by siblings. We used Finnish population registers, including 124,098 children born during 1987–2000. When compared with maternal ages 25–29 years in between-family models, maternal ages of 35–39 years and ≥40 years were associated with percentage increases of 1.1 points (95% confidence intervals: 0.8, 1.4) and 2.2 points (95% confidence intervals: 1.4, 2.9), respectively, in the probability of low birth weight. The associations are similar for the risk of preterm delivery. In within-family models, the relationship between advanced maternal age and low birth weight or preterm birth is statistically and substantively negligible. In Finland, advanced maternal age is not independently associated with the risk of low birth weight or preterm delivery among mothers who have had at least 2 live births. PMID:29206985

Born Too Soon: The global epidemiology of 15 million preterm births

PubMed Central

2013-01-01

This second paper in the Born Too Soon supplement presents a review of the epidemiology of preterm birth, and its burden globally, including priorities for action to improve the data. Worldwide an estimated 11.1% of all livebirths in 2010 were born preterm (14.9 million babies born before 37 weeks of gestation), with preterm birth rates increasing in most countries with reliable trend data. Direct complications of preterm birth account for one million deaths each year, and preterm birth is a risk factor in over 50% of all neonatal deaths. In addition, preterm birth can result in a range of long-term complications in survivors, with the frequency and severity of adverse outcomes rising with decreasing gestational age and decreasing quality of care. The economic costs of preterm birth are large in terms of immediate neonatal intensive care, ongoing long-term complex health needs, as well as lost economic productivity. Preterm birth is a syndrome with a variety of causes and underlying factors usually divided into spontaneous and provider-initiated preterm births. Consistent recording of all pregnancy outcomes, including stillbirths, and standard application of preterm definitions is important in all settings to advance both the understanding and the monitoring of trends. Context specific innovative solutions to prevent preterm birth and hence reduce preterm birth rates all around the world are urgently needed. Strengthened data systems are required to adequately track trends in preterm birth rates and program effectiveness. These efforts must be coupled with action now to implement improved antenatal, obstetric and newborn care to increase survival and reduce disability amongst those born too soon. Declaration This article is part of a supplement jointly funded by Save the Children's Saving Newborn Lives programme through a grant from The Bill & Melinda Gates Foundation and March of Dimes Foundation and published in collaboration with the Partnership for Maternal, Newborn and Child Health and the World Health Organization (WHO). The original article was published in PDF format in the WHO Report "Born Too Soon: the global action report on preterm birth" (ISBN 978 92 4 150343 30), which involved collaboration from more than 50 organizations. The article has been reformatted for journal publication and has undergone peer review according to Reproductive Health's standard process for supplements and may feature some variations in content when compared to the original report. This co-publication makes the article available to the community in a full-text format. PMID:24625129

Effects of Maternal Age and Age-Specific Preterm Birth Rates on Overall Preterm Birth Rates - United States, 2007 and 2014.

PubMed

Ferré, Cynthia; Callaghan, William; Olson, Christine; Sharma, Andrea; Barfield, Wanda

2016-11-04

Reductions in births to teens and preterm birth rates are two recent public health successes in the United States (1,2). From 2007 to 2014, the birth rate for females aged 15-19 years declined 42%, from 41.5 to 24.2 per 1,000 females. The preterm birth rate decreased 8.4%, from 10.41% to 9.54% of live births (1). Rates of preterm births vary by maternal age, being higher among the youngest and oldest mothers. It is unknown how changes in the maternal age distribution in the United States have affected preterm birth rates. CDC used birth data to assess the relative contributions of changes in the maternal age distribution and in age-specific preterm birth rates to the overall decrease in preterm birth rates. The preterm birth rate declined in all age groups. The effects of age distribution changes on the preterm birth rate decrease were different in younger and older mothers. The decrease in the proportion of births to mothers aged ≤19 and 20-24 years and reductions in age-specific preterm rates in all age groups contributed to the overall decline in the preterm birth rate. The increase in births to mothers aged ≥30 years had no effect on the overall preterm birth rate decrease. The decline in preterm births from 2007 to 2014 is related, in part, to teen pregnancy prevention and the changing maternal age distribution. Effective public health strategies for further reducing preterm birth rates need to be tailored to different age groups.

Outdoor Air Pollution, Preterm Birth, and Low Birth Weight: Analysis of the World Health Organization Global Survey on Maternal and Perinatal Health

PubMed Central

Merialdi, Mario; van Donkelaar, Aaron; Vadillo-Ortega, Felipe; Martin, Randall V.; Betran, Ana Pilar; Souza, João Paulo

2014-01-01

Background: Inhaling fine particles (particulate matter with diameter ≤ 2.5 μm; PM2.5) can induce oxidative stress and inflammation, and may contribute to onset of preterm labor and other adverse perinatal outcomes. Objectives: We examined whether outdoor PM2.5 was associated with adverse birth outcomes among 22 countries in the World Health Organization Global Survey on Maternal and Perinatal Health from 2004 through 2008. Methods: Long-term average (2001–2006) estimates of outdoor PM2.5 were assigned to 50-km–radius circular buffers around each health clinic where births occurred. We used generalized estimating equations to determine associations between clinic-level PM2.5 levels and preterm birth and low birth weight at the individual level, adjusting for seasonality and potential confounders at individual, clinic, and country levels. Country-specific associations were also investigated. Results: Across all countries, adjusting for seasonality, PM2.5 was not associated with preterm birth, but was associated with low birth weight [odds ratio (OR) = 1.22; 95% CI: 1.07, 1.39 for fourth quartile of PM2.5 (> 20.2 μg/m3) compared with the first quartile (< 6.3 μg/m3)]. In China, the country with the largest PM2.5 range, preterm birth and low birth weight both were associated with the highest quartile of PM2.5 only, which suggests a possible threshold effect (OR = 2.54; CI: 1.42, 4.55 and OR = 1.99; CI: 1.06, 3.72 for preterm birth and low birth weight, respectively, for PM2.5 ≥ 36.5 μg/m3 compared with PM2.5 < 12.5 μg/m3). Conclusions: Outdoor PM2.5 concentrations were associated with low birth weight but not preterm birth. In rapidly developing countries, such as China, the highest levels of air pollution may be of concern for both outcomes. Citation: Fleischer NL, Merialdi M, van Donkelaar A, Vadillo-Ortega F, Martin RV, Betran AP, Souza JP, O´Neill MS. 2014. Outdoor air pollution, preterm birth, and low birth weight: analysis of the World Health Organization Global Survey on Maternal and Perinatal Health. Environ Health Perspect 122:425–430; http://dx.doi.org/10.1289/ehp.1306837 PMID:24508912

Race and ethnic differences in determinants of preterm birth in the USA: broadening the social context.

PubMed

Reagan, Patricia B; Salsberry, Pamela J

2005-05-01

Preterm births occur in 9.7% of all US singleton births. The rate for blacks is double that of whites and the rate is 25% higher for Hispanics than for whites. While a number of individual correlates with preterm birth have been identified, race and ethnic differences have not been fully explained. Influenced by a growing body of literature documenting a relationship among health, individual income, and neighborhood disadvantage, researchers interested in explaining racial differences in preterm birth are designing studies that extend beyond the individual. No studies of adverse birth outcomes have considered contextual effects beyond the neighborhood level. Only a handful of studies, comparing blacks and whites, have evaluated the influence of neighborhood disadvantage on preterm birth. This study examines how preterm birth among blacks, whites and Hispanics is influenced by social context, broadly defined to include measures of neighborhood disadvantage and cumulative exposure to state-level income inequality, controlling for individual risk factors. Neighborhood disadvantage is determined by Census tract data. Cumulative exposure to income inequality is measured by the fraction of the mother's life since age 14 spent residing in states with a state-level Gini coefficient above the median. The results for neighborhood disadvantage are highly sensitive across race/ethnicities to the measure used. We find evidence that neighborhood poverty rates and housing vacancy rates increased the rate of very preterm birth and decreased the rate of moderately preterm birth for blacks. The rate of very preterm increased with the fraction of female-headed households for Hispanics and decreased with the fraction of people employed in professional occupations for whites. We find direct effects of cumulative exposure to income inequality only for Hispanics. However, we do find indirect effects of context broadly defined on behaviors that increased the risk of preterm birth.

Intestinal microbiota is different in women with preterm birth: results from terminal restriction fragment length polymorphism analysis.

PubMed

Shiozaki, Arihiro; Yoneda, Satoshi; Yoneda, Noriko; Yonezawa, Rika; Matsubayashi, Takamichi; Seo, Genichiro; Saito, Shigeru

2014-01-01

Preterm birth is a leading cause of perinatal morbidity and mortality. Studies using a cultivation method or molecular identification have shown that bacterial vaginosis is one of the risk factors for preterm birth. However, an association between preterm birth and intestinal microbiota has not been reported using molecular techniques, although the vaginal microbiota changes during pregnancy. Our aim here was to clarify the difference in intestinal and vaginal microbiota between women with preterm birth and women without preterm labor. 16S ribosomal ribonucleic acid genes were amplified from fecal and vaginal DNA by polymerase chain reaction. Using terminal restriction fragment length polymorphism (T-RFLP), we compared the levels of operational taxonomic units of both intestinal and vaginal flora among three groups: pregnant women who delivered term babies without preterm labor (non-PTL group) (n = 20), those who had preterm labor but delivered term babies (PTL group) (n = 11), and those who had preterm birth (PTB group) (n = 10). Significantly low levels of Clostridium subcluster XVIII, Clostridium cluster IV, Clostridium subcluster XIVa, and Bacteroides, and a significantly high level of Lactobacillales were observed in the intestinal microbiota in the PTB group compared with those in the non-PTL group. The levels of Clostridium subcluster XVIII and Clostridium subcluster XIVa in the PTB group were significantly lower than those in the PTL group, and these levels in the PTL group were significantly lower than those in non-PTL group. However, there were no significant differences in vaginal microbiota among the three groups. Intestinal microbiota in the PTB group was found to differ from that in the non-PTL group using the T-RFLP method.

Influence of slight to moderate risk for birth hypoxia on acquisition of cognitive and language function in the preterm infant: a cross-sectional comparison with preterm-birth controls.

PubMed

Hopkins-Golightly, Tracy; Raz, Sarah; Sander, Craig J

2003-01-01

The cognitive and language performance of a group of 26 preterm-birth preschool and early school-age children with slight to moderate risk for perinatal hypoxia was compared with the performance of a preterm-birth comparison group of 26 children. Despite the relatively small discrepancy in degree of risk, the cognitive performance of the 2 groups diverged significantly. When data for children with known perinatal arterial pH were combined, a curvilinear (quadratic) regression model provided the best fit. Increasing acidosis was linearly related to decreases in cognitive skills, with the bend in the curve occurring well within the normal range of pH values. Hence, in the preterm infant, even minor risk for birth hypoxia may result in discernible deviation from the expected developmental trajectory.

Association of maternal serum cadmium level during pregnancy with risk of preterm birth in a Chinese population.

PubMed

Wang, Hua; Liu, Lu; Hu, Yong-Fang; Hao, Jia-Hu; Chen, Yuan-Hua; Su, Pu-Yu; Yu, Zhen; Fu, Lin; Tao, Fang-Biao; Xu, De-Xiang

2016-09-01

Cadmium (Cd) was a developmental toxicant that induces fetal malformation and growth restriction in mice. However, epidemiological studies about the association of maternal serum Cd level with risk of preterm birth were limited. This study was to investigate whether maternal serum Cd level during pregnancy is associated with risk of preterm birth in a Chinese population. Total 3254 eligible mother-and-singleton-offspring pairs were recruited. Maternal serum Cd level was measured by GFAAS. Based on tertiles, maternal serum Cd concentration was classified as low (LCd, <0.65 μg/L), medium (MCd, 0.65-0.94 μg/L) and high (HCd, ≥0.95 μg/L). Odds ratio (OR) for preterm birth was estimated using multiple logistic regression models. Results showed the rate of preterm birth among LCd, M-Cd and HCd was 3.5%, 3.8%, and 9.4%, respectively. Subjects with HCd had a significantly higher risk for preterm birth (OR: 2.86; 95%CI: 1.95, 4.19; P < 0.001) than did those with LCd. Adjusted OR for preterm birth was 3.02 (95%CI: 2.02, 4.50; P < 0.001) among subjects with HCd compared to subjects with LCd. Taken together, the above results suggest that maternal serum Cd level during pregnancy is positively associated with risk of preterm birth. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparing regional infant death rates: the influence of preterm births <24 weeks of gestation.

PubMed

Smith, Lucy; Draper, Elizabeth S; Manktelow, Bradley N; Pritchard, Catherine; Field, David John

2013-03-01

To investigate regional variation in the registration of preterm births <24 weeks of gestation and the impact on infant death rates for English Primary Care Trusts (PCTs). Cohort study. England. All registered births (1 January 2005-31 December 2008) by gestational age and PCT (147 trusts) linked to infant deaths (up to 1 year of life). Late-fetal deaths at 22 and 23 weeks gestation (1 January 2005-31 December 2006). Extremely preterm (<24 weeks) birth rate per 1000 live births and percentage of births registered as live born by PCT. Infant death rate and rank of mortality for (1) all live births and (2) live births over 24 weeks gestation by PCT. Wide between-PCT variation existed in extremely preterm birth (<24 weeks) rates (per 1000 births) (90% central range (0.31, 1.91)) and percentages of births <24 weeks of gestation registered as live born (median 52.6%, 90% central range (26.3%, 79.5%)). Consequently, the percentage of infant deaths arising from these births varied (90% central range (6.7%, 31.9%)). Excluding births <24 weeks, led to significant changes in infant mortality rankings of PCTs, with a median worsening of 12 places for PCTs with low rates of live born preterm births <24 weeks of gestation compared with a median improvement of four ranks for those with higher live birth registration rates. Infant death rates in PCTs in England are influenced by variation in the registration of births where viability is uncertain. It is vital that this variation is minimised before infant mortality is used as indicator for monitoring health and performance and targeting interventions.

Determining gestational age and preterm birth in rural Guatemala: A comparison of methods.

PubMed

Weinstein, John R; Thompson, Lisa M; Díaz Artiga, Anaité; Bryan, Joe P; Arriaga, William E; Omer, Saad B; McCracken, John P

2018-01-01

Preterm birth is the leading cause of death among children <5 years of age. Accurate determination of prematurity is necessary to provide appropriate neonatal care and guide preventive measures. To estimate the most accurate method to identify infants at risk for adverse outcomes, we assessed the validity of two widely available methods-last menstrual period (LMP) and the New Ballard (NB) neonatal assessment-against ultrasound in determining gestational age and preterm birth in highland Guatemala. Pregnant women (n = 188) were recruited with a gestational age <20 weeks and followed until delivery. Ultrasound was performed by trained physicians and LMP was collected during recruitment. NB was performed on infants within 96 hours of birth by trained study nurses. LMP and NB accuracy at determining gestational age and identifying prematurity was assessed by comparing them to ultrasound. By ultrasound, infant mean gestational age at birth was 38.3 weeks (SD = 1.6) with 16% born at less than 37 gestation. LMP was more accurate than NB (mean difference of +0.13 weeks for LMP and +0.61 weeks for NB). However, LMP and NB estimates had low agreement with ultrasound-determined gestational age (Lin's concordance<0.48 for both methods) and preterm birth (κ<0.29 for both methods). By LMP, 18% were judged premature compared with 6% by NB. LMP underestimated gestational age among women presenting later to prenatal care (0.18 weeks for each additional week). Gestational age for preterm infants was overestimated by nearly one week using LMP and nearly two weeks using NB. New Ballard neuromuscular measurements were more predictive of preterm birth than those measuring physical criteria. In an indigenous population in highland Guatemala, LMP overestimated prematurity by 2% and NB underestimated prematurity by 10% compared with ultrasound estimates. New, simple and accurate methods are needed to identify preterm birth in resource-limited settings worldwide.

Determining gestational age and preterm birth in rural Guatemala: A comparison of methods

PubMed Central

Thompson, Lisa M.; Díaz Artiga, Anaité; Bryan, Joe P.; Arriaga, William E.; Omer, Saad B.; McCracken, John P.

2018-01-01

Background Preterm birth is the leading cause of death among children <5 years of age. Accurate determination of prematurity is necessary to provide appropriate neonatal care and guide preventive measures. To estimate the most accurate method to identify infants at risk for adverse outcomes, we assessed the validity of two widely available methods—last menstrual period (LMP) and the New Ballard (NB) neonatal assessment—against ultrasound in determining gestational age and preterm birth in highland Guatemala. Methods Pregnant women (n = 188) were recruited with a gestational age <20 weeks and followed until delivery. Ultrasound was performed by trained physicians and LMP was collected during recruitment. NB was performed on infants within 96 hours of birth by trained study nurses. LMP and NB accuracy at determining gestational age and identifying prematurity was assessed by comparing them to ultrasound. Results By ultrasound, infant mean gestational age at birth was 38.3 weeks (SD = 1.6) with 16% born at less than 37 gestation. LMP was more accurate than NB (mean difference of +0.13 weeks for LMP and +0.61 weeks for NB). However, LMP and NB estimates had low agreement with ultrasound-determined gestational age (Lin’s concordance<0.48 for both methods) and preterm birth (κ<0.29 for both methods). By LMP, 18% were judged premature compared with 6% by NB. LMP underestimated gestational age among women presenting later to prenatal care (0.18 weeks for each additional week). Gestational age for preterm infants was overestimated by nearly one week using LMP and nearly two weeks using NB. New Ballard neuromuscular measurements were more predictive of preterm birth than those measuring physical criteria. Conclusion In an indigenous population in highland Guatemala, LMP overestimated prematurity by 2% and NB underestimated prematurity by 10% compared with ultrasound estimates. New, simple and accurate methods are needed to identify preterm birth in resource-limited settings worldwide. PMID:29554145

Cross-Country Individual Participant Analysis of 4.1 Million Singleton Births in 5 Countries with Very High Human Development Index Confirms Known Associations but Provides No Biologic Explanation for 2/3 of All Preterm Births

PubMed Central

Ferrero, David M.; Jacobsson, Bo; Di Renzo, Gian Carlo; Norman, Jane E.; Martin, James N.; D’Alton, Mary; Castelazo, Ernesto; Howson, Chris P.; Sengpiel, Verena; Bottai, Matteo; Mayo, Jonathan A.; Shaw, Gary M.; Verdenik, Ivan; Tul, Nataša; Velebil, Petr; Cairns-Smith, Sarah; Rushwan, Hamid; Arulkumaran, Sabaratnam; Howse, Jennifer L.; Simpson, Joe Leigh

2016-01-01

Background Preterm birth is the most common single cause of perinatal and infant mortality, affecting 15 million infants worldwide each year with global rates increasing. Understanding of risk factors remains poor, and preventive interventions have only limited benefit. Large differences exist in preterm birth rates across high income countries. We hypothesized that understanding the basis for these wide variations could lead to interventions that reduce preterm birth incidence in countries with high rates. We thus sought to assess the contributions of known risk factors for both spontaneous and provider-initiated preterm birth in selected high income countries, estimating also the potential impact of successful interventions due to advances in research, policy and public health, or clinical practice. Methods We analyzed individual patient-level data on 4.1 million singleton pregnancies from four countries with very high human development index (Czech Republic, New Zealand, Slovenia, Sweden) and one comparator U.S. state (California) to determine the specific contribution (adjusting for confounding effects) of 21 factors. Both individual and population-attributable preterm birth risks were determined, as were contributors to cross-country differences. We also assessed the ability to predict preterm birth given various sets of known risk factors. Findings Previous preterm birth and preeclampsia were the strongest individual risk factors of preterm birth in all datasets, with odds ratios of 4.6–6.0 and 2.8–5.7, respectively, for individual women having those characteristics. In contrast, on a population basis, nulliparity and male sex were the two risk factors with the highest impact on preterm birth rates, accounting for 25–50% and 11–16% of excess population attributable risk, respectively (p<0.001). The importance of nulliparity and male sex on population attributable risk was driven by high prevalence despite low odds ratios for individual women. More than 65% of the total aggregated risk of preterm birth within each country lacks a plausible biologic explanation, and 63% of difference between countries cannot be explained with known factors; thus, research is necessary to elucidate the underlying mechanisms of preterm birth and, hence, therapeutic intervention. Surprisingly, variation in prevalence of known risk factors accounted for less than 35% of the difference in preterm birth rates between countries. Known risk factors had an area under the curve of less than 0.7 in ROC analysis of preterm birth prediction within countries. These data suggest that other influences, as yet unidentified, are involved in preterm birth. Further research into biological mechanisms is warranted. Conclusions We have quantified the causes of variation in preterm birth rates among countries with very high human development index. The paucity of explicit and currently identified factors amenable to intervention illustrates the limited impact of changes possible through current clinical practice and policy interventions. Our research highlights the urgent need for research into underlying biological causes of preterm birth, which alone are likely to lead to innovative and efficacious interventions. PMID:27622562

Cross-Country Individual Participant Analysis of 4.1 Million Singleton Births in 5 Countries with Very High Human Development Index Confirms Known Associations but Provides No Biologic Explanation for 2/3 of All Preterm Births.

PubMed

Ferrero, David M; Larson, Jim; Jacobsson, Bo; Di Renzo, Gian Carlo; Norman, Jane E; Martin, James N; D'Alton, Mary; Castelazo, Ernesto; Howson, Chris P; Sengpiel, Verena; Bottai, Matteo; Mayo, Jonathan A; Shaw, Gary M; Verdenik, Ivan; Tul, Nataša; Velebil, Petr; Cairns-Smith, Sarah; Rushwan, Hamid; Arulkumaran, Sabaratnam; Howse, Jennifer L; Simpson, Joe Leigh

2016-01-01

Preterm birth is the most common single cause of perinatal and infant mortality, affecting 15 million infants worldwide each year with global rates increasing. Understanding of risk factors remains poor, and preventive interventions have only limited benefit. Large differences exist in preterm birth rates across high income countries. We hypothesized that understanding the basis for these wide variations could lead to interventions that reduce preterm birth incidence in countries with high rates. We thus sought to assess the contributions of known risk factors for both spontaneous and provider-initiated preterm birth in selected high income countries, estimating also the potential impact of successful interventions due to advances in research, policy and public health, or clinical practice. We analyzed individual patient-level data on 4.1 million singleton pregnancies from four countries with very high human development index (Czech Republic, New Zealand, Slovenia, Sweden) and one comparator U.S. state (California) to determine the specific contribution (adjusting for confounding effects) of 21 factors. Both individual and population-attributable preterm birth risks were determined, as were contributors to cross-country differences. We also assessed the ability to predict preterm birth given various sets of known risk factors. Previous preterm birth and preeclampsia were the strongest individual risk factors of preterm birth in all datasets, with odds ratios of 4.6-6.0 and 2.8-5.7, respectively, for individual women having those characteristics. In contrast, on a population basis, nulliparity and male sex were the two risk factors with the highest impact on preterm birth rates, accounting for 25-50% and 11-16% of excess population attributable risk, respectively (p<0.001). The importance of nulliparity and male sex on population attributable risk was driven by high prevalence despite low odds ratios for individual women. More than 65% of the total aggregated risk of preterm birth within each country lacks a plausible biologic explanation, and 63% of difference between countries cannot be explained with known factors; thus, research is necessary to elucidate the underlying mechanisms of preterm birth and, hence, therapeutic intervention. Surprisingly, variation in prevalence of known risk factors accounted for less than 35% of the difference in preterm birth rates between countries. Known risk factors had an area under the curve of less than 0.7 in ROC analysis of preterm birth prediction within countries. These data suggest that other influences, as yet unidentified, are involved in preterm birth. Further research into biological mechanisms is warranted. We have quantified the causes of variation in preterm birth rates among countries with very high human development index. The paucity of explicit and currently identified factors amenable to intervention illustrates the limited impact of changes possible through current clinical practice and policy interventions. Our research highlights the urgent need for research into underlying biological causes of preterm birth, which alone are likely to lead to innovative and efficacious interventions.

A Cross-Species Analysis of Animal Models for the Investigation of Preterm Birth Mechanisms

PubMed Central

Nielsen, Brian W.; Bonney, Elizabeth A.; Pearce, Bradley D.; Donahue, Leah Rae; Sarkar, Indra Neil

2015-01-01

Background: Spontaneous preterm birth is the leading cause of neonatal morbidity and mortality worldwide. The ability to examine the exact mechanisms underlying this syndrome in humans is limited. Therefore, the study of animal models is critical to unraveling the key physiologic mechanisms that control the timing of birth. The purpose of this review is to facilitate enhanced assimilation of the literature on animal models of preterm birth by a broad range of investigators. Methods: Using classical systematic and informatics search techniques of the available literature through 2012, a database of intact animal models was generated. Research librarians generated a list of articles using multiple databases. From these articles, a comprehensive list of Medical Subject Headings (MeSH) was created. Using mathematical modeling, significant MeSH descriptors were determined, and a MEDLINE search algorithm was created. The articles were reviewed for mechanism of labor induction categorized by species. Results: Existing animal models of preterm birth comprise specific interventions to induce preterm birth, as no animal model was identified that exhibits natural spontaneous preterm birth at an incidence comparable to that of the humans. A search algorithm was developed which when used results in a comprehensive list of agents used to induce preterm delivery in a host of animal species. The evolution of 3 specific animal models—sheep, mice, and rats—has demonstrated a clear shift in focus in the literature from endocrine to inflammatory agents of preterm birth induction. Conclusion: The process of developing a search algorithm to provide efficient access to information on animal models of preterm birth illustrates the need for a more precise organization of the literature to allow the investigator to focus on distinctly maternal versus fetal outcomes. PMID:26377998

Density of Stromal Cells and Macrophages Associated With Collagen Remodeling in the Human Cervix in Preterm and Term Birth

PubMed Central

Dubicke, Aurelija; Ekman-Ordeberg, Gunvor; Mazurek, Patricia; Miller, Lindsay; Yellon, Steven M.

2015-01-01

Remodeling of the cervix occurs in advance of labor both at term and at preterm birth. Morphological characteristics associated with remodeling in rodents were assessed in cervix biopsies from women at term (39 weeks’ gestation) and preterm (<33 weeks’ gestation). Collagen I and III messenger RNA and hydroxyproline concentrations declined in cervix biopsies from women in labor at term and preterm compared to that in the cervix from nonlaboring women. Extracellular collagen was more degraded in sections of cervix from women at term, based on optical density of picrosirius red stain, versus that in biopsies from nonpregnant women. However, collagen structure was unchanged in the cervix from women at preterm labor versus the nonpregnant group. As an indication of inflammation, cell nuclei density was decreased in cervix biopsies from pregnant women irrespective of labor compared to the nonpregnant group. Moreover, CD68-stained macrophages increased to an equivalent extent in cervix subepithelium and stroma from groups in labor, both at term and preterm, as well as in women not in labor at term. Evidence for a similar inflammatory process in the remodeled cervix of women at term and preterm birth parallels results in rodent models. Thus, a conserved final common mechanism involving macrophages and inflammation may characterize the transition to a ripe cervix before birth at term and in advance of premature birth. PMID:26608218

Epidemiology and causes of preterm birth.

PubMed

Goldenberg, Robert L; Culhane, Jennifer F; Iams, Jay D; Romero, Roberto

2008-01-05

This paper is the first in a three-part series on preterm birth, which is the leading cause of perinatal morbidity and mortality in developed countries. Infants are born preterm at less than 37 weeks' gestational age after: (1) spontaneous labour with intact membranes, (2) preterm premature rupture of the membranes (PPROM), and (3) labour induction or caesarean delivery for maternal or fetal indications. The frequency of preterm births is about 12-13% in the USA and 5-9% in many other developed countries; however, the rate of preterm birth has increased in many locations, predominantly because of increasing indicated preterm births and preterm delivery of artificially conceived multiple pregnancies. Common reasons for indicated preterm births include pre-eclampsia or eclampsia, and intrauterine growth restriction. Births that follow spontaneous preterm labour and PPROM-together called spontaneous preterm births-are regarded as a syndrome resulting from multiple causes, including infection or inflammation, vascular disease, and uterine overdistension. Risk factors for spontaneous preterm births include a previous preterm birth, black race, periodontal disease, and low maternal body-mass index. A short cervical length and a raised cervical-vaginal fetal fibronectin concentration are the strongest predictors of spontaneous preterm birth.

Post-hoc analysis of vitamin D status and reduced risk of preterm birth in two vitamin D pregnancy cohorts compared with South Carolina March of Dimes 2009-2011 rates.

PubMed

Wagner, C L; Baggerly, C; McDonnell, S; Baggerly, K A; French, C B; Baggerly, L; Hamilton, S A; Hollis, B W

2016-01-01

Two vitamin D pregnancy supplementation trials were recently undertaken in South Carolina: The NICHD (n=346) and Thrasher Research Fund (TRF, n=163) studies. The findings suggest increased dosages of supplemental vitamin D were associated with improved health outcomes of both mother and newborn, including risk of preterm birth (<37 weeks gestation). How that risk was associated with 25(OH)D serum concentration, a better indicator of vitamin D status than dosage, by race/ethnic group and the potential impact in the community was not previously explored. While a recent IOM report suggested a concentration of 20 ng/mL should be targeted, more recent work suggests optimal conversion of 25(OH)D-1,25(OH)2D takes place at 40 ng/mL in pregnant women. Post-hoc analysis of the relationship between 25(OH)D concentration and preterm birth rates in the NICHD and TRF studies with comparison to Charleston County, South Carolina March of Dimes (CC-MOD) published rates of preterm birth to assess potential risk reduction in the community. Using the combined cohort datasets (n=509), preterm birth rates both for the overall population and for the subpopulations achieving 25(OH)D concentrations of ≤20 ng/mL, >20 to <40 ng/mL, and ≥40 ng/mL were calculated; subpopulations broken down by race/ethnicity were also examined. Log-binomial regression was used to test if an association between 25(OH)D serum concentration and preterm birth was present when adjusted for covariates; locally weighted regression (LOESS) was used to explore the relationship between 25(OH)D concentration and gestational age (weeks) at delivery in more detail. These rates were compared with 2009-2011 CC-MOD data to assess potential risk reductions in preterm birth. Women with serum 25(OH)D concentrations ≥40 ng/mL (n=233) had a 57% lower risk of preterm birth compared to those with concentrations ≤20 ng/mL [n=82; RR=0.43, 95% confidence interval (CI)=0.22,0.83]; this lower risk was essentially unchanged after adjusting for covariates (RR=0.41, 95% CI=0.20,0.86). The fitted LOESS curve shows gestation week at birth initially rising steadily with increasing 25(OH)D and then plateauing at ∼40 ng/mL. Broken down by race/ethnicity, there was a 79% lower risk of preterm birth among Hispanic women with 25(OH)D concentrations ≥40 ng/mL (n=92) compared to those with 25(OH)D concentrations ≤20 ng/mL (n=29; RR=0.21, 95% CI=0.06,0.69) and a 45% lower risk among Black women (n=52 and n=50; RR=0.55, 95% CI=0.17,1.76). There were too few white women with low 25(OH)D concentrations for assessment (n=3). Differences by race/ethnicity were not statistically significant with 25(OH)D included as a covariate. Compared to the CC-MOD reference group, women with serum concentrations ≥40 ng/mL in the combined cohort had a 46% lower rate of preterm birth overall (n=233, p=0.004) with a 66% lower rate among Hispanic women (n=92, p=0.01) and a 58% lower rate among black women (n=52, p=0.04). In this post-hoc analysis, achieving a 25(OH)D serum concentration ≥40 ng/mL significantly decreased the risk of preterm birth compared to ≤20 ng/mL. These findings suggest the importance of raising 25(OH)D levels substantially above 20 ng/mL; reaching 40 ng/mL during pregnancy would reduce the risk of preterm birth and achieve the maximal production of the active hormone. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Preterm birth time trends in Europe: a study of 19 countries

PubMed Central

Zeitlin, J; Szamotulska, K; Drewniak, N; Mohangoo, AD; Chalmers, J; Sakkeus, L; Irgens, L; Gatt, M; Gissler, M; Blondel, B

2013-01-01

Objective To investigate time trends in preterm birth in Europe by multiplicity, gestational age, and onset of delivery. Design Analysis of aggregate data from routine sources. Setting Nineteen European countries. Population Live births in 1996, 2000, 2004, and 2008. Methods Annual risk ratios of preterm birth in each country were estimated with year as a continuous variable for all births and by subgroup using log-binomial regression models. Main outcome measures Overall preterm birth rate and rate by multiplicity, gestational age group, and spontaneous versus non-spontaneous (induced or prelabour caesarean section) onset of labour. Results Preterm birth rates rose in most countries, but the magnitude of these increases varied. Rises in the multiple birth rate as well as in the preterm birth rate for multiple births contributed to increases in the overall preterm birth rate. About half of countries experienced no change or decreases in the rates of singleton preterm birth. Where preterm birth rates rose, increases were no more prominent at 35–36 weeks of gestation than at 32–34 weeks of gestation. Variable trends were observed for spontaneous and non-spontaneous preterm births in the 13 countries with mode of onset data; increases were not solely attributed to non-spontaneous preterm births. Conclusions There was a wide variation in preterm birth trends in European countries. Many countries maintained or reduced rates of singleton preterm birth over the past 15 years, challenging a widespread belief that rising rates are the norm. Understanding these cross-country differences could inform strategies for the prevention of preterm birth. PMID:23700966

Antibiotics for ureaplasma in the vagina in pregnancy.

PubMed

Raynes Greenow, Camille H; Roberts, Christine L; Bell, Jane C; Peat, Brian; Gilbert, Gwendolyn L; Parker, Sharon

2011-09-07

Preterm birth is a significant perinatal problem contributing to perinatal morbidity and mortality. Heavy vaginal ureaplasma colonisation is suspected of playing a role in preterm birth and preterm rupture of the membranes. Antibiotics are used to treat infections and have been used to treat pregnant women with preterm prelabour rupture of the membranes, resulting in some short-term improvements. However, the benefit of using antibiotics in early pregnancy to treat heavy vaginal colonisation is unclear. To assess whether antibiotic treatment of pregnant women with heavy vaginal ureaplasma colonisation reduces the incidence of preterm birth and other adverse pregnancy outcomes. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 May 2011). Randomised controlled trials comparing any antibiotic regimen with placebo or no treatment in pregnant women with ureaplasma detected in the vagina. Three review authors independently assessed eligibility and trial quality and extracted data. We included one trial, involving 1071 women. Of these, 644 women between 22 weeks and 32 weeks' gestation were randomly assigned to one of three groups of antibiotic treatment (n = 174 erythromycin estolate, n = 224 erythromycin stearate, and n = 246 clindamycin hydrochloride) or a placebo (n = 427). Preterm birth data was not reported in this trial. Incidence of low birthweight less than 2500 grams was only evaluated for erythromycin (combined, n = 398) compared to placebo (n = 427) and there was no statistically significant difference between the two groups (risk ratio (RR) 0.70, 95% confidence interval (CI) 0.46 to 1.07). There were no statistically significant differences in side effects sufficient to stop treatment between either group (RR 1.25, 95% CI 0.85 to 1.85). There is insufficient evidence to assess whether pregnant women who have vaginal colonisation with ureaplasma should be treated with antibiotics to prevent preterm birth.Preterm birth is a significant perinatal problem. Upper genital tract infections, including ureaplasmas, are suspected of playing a role in preterm birth and preterm rupture of the membranes. Antibiotics are used to treat women with preterm prelabour rupture of the membranes; this may result in prolongation of pregnancy and lowers the risks of maternal and neonatal infection. However, antibiotics may be beneficial earlier in pregnancy to eradicate potentially causative agents.

Clinical and Cost Impact Analysis of a Novel Prognostic Test for Early Detection of Preterm Birth

PubMed Central

Caughey, Aaron B.; Zupancic, John A. F.; Greenberg, James M.; Garfield, Susan S.; Thung, Stephen F.; Iams, Jay D.

2016-01-01

Objective The objective of this study was to evaluate the potential impact to the U.S. health care system by adopting a novel test that identifies women at risk for spontaneous preterm birth. Methods A decision-analytic model was developed to assess clinical and cost outcomes over a 1-year period. The use of a prognostic test to predict spontaneous preterm birth in a hypothetical population of women reflective of the U.S. population (predictive arm) was compared with the current baseline rate of spontaneous preterm birth and associated infant morbidity and mortality (baseline care arm). Results In a population of 3,528,593 births, our model predicts a 23.5% reduction in infant mortality (8,300 vs. 6,343 deaths) with use of the novel test. The rate of acute conditions at birth decreased from 11.2 to 8.1%; similarly, the rate of developmental disabilities decreased from 13.2 to 11.5%. The rate of spontaneous preterm birth decreased from 9.8 to 9.1%, a reduction of 23,430 preterm births. Direct medical costs savings was $511.7M (− 2.1%) in the first year of life. Discussion The use of a prognostic test for reducing spontaneous preterm birth is a dominant strategy that could reduce costs and improve outcomes. More research is needed once such a test is available to determine if these results are borne out upon real-world use. PMID:27917307

Early microvascular changes in the preterm neonate: a comparative study of the human and guinea pig.

PubMed

Dyson, Rebecca M; Palliser, Hannah K; Lakkundi, Anil; de Waal, Koert; Latter, Joanna L; Clifton, Vicki L; Wright, Ian M R

2014-09-17

Dysfunction of the transition from fetal to neonatal circulatory systems may be a major contributor to poor outcome following preterm birth. Evidence exists in the human for both a period of low flow between 5 and 11 h and a later period of increased flow, suggesting a hypoperfusion-reperfusion cycle over the first 24 h following birth. Little is known about the regulation of peripheral blood flow during this time. The aim of this study was to conduct a comparative study between the human and guinea pig to characterize peripheral microvascular behavior during circulatory transition. Very preterm (≤28 weeks GA), preterm (29-36 weeks GA), and term (≥37 weeks GA) human neonates underwent laser Doppler analysis of skin microvascular blood flow at 6 and 24 h from birth. Guinea pig neonates were delivered prematurely (62 day GA) or at term (68-71 day GA) and laser Doppler analysis of skin microvascular blood flow was assessed every 2 h from birth. In human preterm neonates, there is a period of high microvascular flow at 24 h after birth. No period of low flow was observed at 6 h. In preterm animals, microvascular flow increased after birth, reaching a peak at 10 h postnatal age. Blood flow then steadily decreased, returning to delivery levels by 24 h. Preterm birth was associated with higher baseline microvascular flow throughout the study period in both human and guinea pig neonates. The findings do not support a hypoperfusion-reperfusion cycle in the microcirculation during circulatory transition. The guinea pig model of preterm birth will allow further investigation of the mechanisms underlying microvascular function and dysfunction during the initial extrauterine period. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Cold-knife conisation and large loop excision of transformation zone significantly increase the risk for spontaneous preterm birth: a population-based cohort study.

PubMed

Jančar, Nina; Mihevc Ponikvar, Barbara; Tomšič, Sonja

2016-08-01

Our aim was to explore the association between cold-knife conisation and large loop excision of transformation zone (LLETZ) with spontaneous preterm birth in a large 10-year national sample. We wanted to explore further the association of these procedures with preterm birth according to gestation. We conducted a population based retrospective cohort study, using data from national Medical Birth Registry. The study population consisted of all women giving birth to singletons in the period 2003-2012 in Slovenia, excluding all induced labors and elective cesarean sections before 37 weeks of gestation (N=192730). We compared the prevalence of spontaneous preterm births (before 28 weeks, before 32 weeks, before 34 weeks and before 37 weeks of gestation) in women with cold-knife conisation or LLETZ compared to women without history of conisation, calculating odds ratios (OR), adjusted for potential confounders. Chi-square test was used for descriptive analysis. Logistic regression analyses were performed to estimate crude odds ratio (OR) and adjusted odds ratio (aOR) and their 95% confidence intervals (95% CI) with two-sided probability (p) values. A total of 8420 (4.4%) women had a preterm birth before 37 weeks of gestation, 2250 (1.2%) before 34 weeks of gestation, 1333 (0.7%) before 32 weeks of gestation and 603 (0.3%) before 28 weeks of gestation. A total of 4580 (2.4%) women had some type of conisation in their medical history: 2083 (1.1%) had cold-knife conisation and 2498 (1.3%) had LLETZ. In women with history of cold-knife conisation, the adjusted OR for preterm birth before 37 weeks of gestation was 3.13 (95% CI; 2.74-3.57) and for preterm birth before 28 weeks of gestation 5.96 (95% CI; 4.3-8.3). In women with history of LLETZ, the adjusted OR was 1.95 (95% CI; 1.68-2.25) and 2.88 (95% CI; 1.87-4.43), respectively. Women with cervical excision procedure of any kind have significantly increased odds for preterm birth, especially for preterm birth before 28 weeks and before 32 weeks of gestation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Spatial and temporal patterns in preterm birth in the United States.

PubMed

Byrnes, John; Mahoney, Richard; Quaintance, Cele; Gould, Jeffrey B; Carmichael, Suzan; Shaw, Gary M; Showen, Amy; Phibbs, Ciaran; Stevenson, David K; Wise, Paul H

2015-06-01

Despite years of research, the etiologies of preterm birth remain unclear. In order to help generate new research hypotheses, this study explored spatial and temporal patterns of preterm birth in a large, total-population dataset. Data on 145 million US births in 3,000 counties from the Natality Files of the National Center for Health Statistics for 1971-2011 were examined. State trends in early (<34 wk) and late (34-36 wk) preterm birth rates were compared. K-means cluster analyses were conducted to identify gestational age distribution patterns for all US counties over time. A weak association was observed between state trends in <34 wk birth rates and the initial absolute <34 wk birth rate. Significant associations were observed between trends in <34 wk and 34-36 wk birth rates and between white and African American <34 wk births. Periodicity was observed in county-level trends in <34 wk birth rates. Cluster analyses identified periods of significant heterogeneity and homogeneity in gestational age distributional trends for US counties. The observed geographic and temporal patterns suggest periodicity and complex, shared influences among preterm birth rates in the United States. These patterns could provide insight into promising hypotheses for further research.

Advanced Maternal Age and the Risk of Low Birth Weight and Preterm Delivery: a Within-Family Analysis Using Finnish Population Registers.

PubMed

Goisis, Alice; Remes, Hanna; Barclay, Kieron; Martikainen, Pekka; Myrskylä, Mikko

2017-12-01

Advanced maternal age at birth is considered a major risk factor for birth outcomes. It is unclear to what extent this association is confounded by maternal characteristics. To test whether advanced maternal age at birth independently increases the risk of low birth weight (<2,500 g) and preterm birth (<37 weeks' gestation), we compared between-family models (children born to different mothers at different ages) with within-family models (children born to the same mother at different ages). The latter procedure reduces confounding by unobserved parental characteristics that are shared by siblings. We used Finnish population registers, including 124,098 children born during 1987-2000. When compared with maternal ages 25-29 years in between-family models, maternal ages of 35-39 years and ≥40 years were associated with percentage increases of 1.1 points (95% confidence intervals: 0.8, 1.4) and 2.2 points (95% confidence intervals: 1.4, 2.9), respectively, in the probability of low birth weight. The associations are similar for the risk of preterm delivery. In within-family models, the relationship between advanced maternal age and low birth weight or preterm birth is statistically and substantively negligible. In Finland, advanced maternal age is not independently associated with the risk of low birth weight or preterm delivery among mothers who have had at least 2 live births. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Twins: prevalence, problems, and preterm births.

PubMed

Chauhan, Suneet P; Scardo, James A; Hayes, Edward; Abuhamad, Alfred Z; Berghella, Vincenzo

2010-10-01

The rate of twin pregnancies in the United States has stabilized at 32 per 1000 births in 2006. Aside from determining chorionicity, first-trimester screening and second-trimester ultrasound scanning should ascertain whether there are structural or chromosomal abnormalities. Compared with singleton births, genetic amniocentesis-related loss at <24 weeks of gestation for twin births is higher (0.9% vs 2.9%, respectively). Selective termination for an anomalous fetus is an option, although the pregnancy loss rate is 7% at experienced centers. For singleton and twin births for African American and white women, approximately 50% of preterm births are indicated; approximately one-third of these births are spontaneous, and 10% of the births occur after preterm premature rupture of membranes. From 1989-2000, the rate of preterm twin births increased, for African American and white women alike, although the perinatal mortality rate has actually decreased. As with singleton births, tocolytics should be used judiciously and only for a limited time (<48 hours) in twin births. Administration of antenatal corticosteroids is an evidence-based recommendation. Copyright © 2010 Mosby, Inc. All rights reserved.

Increased risk of preterm birth in singleton pregnancies after blastocyst versus Day 3 embryo transfer: Canadian ART Register (CARTR) analysis.

PubMed

Dar, S; Librach, C L; Gunby, J; Bissonnette, F; Cowan, L

2013-04-01

Are the fetal outcomes of singleton pregnancies that result from cleavage stage embryo transfer (ET) different from the outcomes from Day 5/6 blastocyst stage ET? There was a significantly higher risk of preterm birth (<37 weeks) in singletons after extended embryo culture (Day 5/6) compared with cleavage stage (Day 3) transfer. Two recent studies, from Sweden and the USA, reported an increased risk of preterm birth in singleton pregnancies after Day 5/6 ET compared with Day 3 ET. The US study also showed increased early preterm births and the Swedish study showed increased fetal malformations in this group. A retrospective cohort study was performed. Data were collected from the Canadian ART Register database for all singleton births after fresh IVF/ICSI ET cycles (2001-2009). A total of 12 712 singleton births were included. Of these, 9506 resulted from a Day 3 ET and 3206 resulted from a blastocyst (Day 5/6) ET. Preterm birth rate <37 weeks (unadjusted by potential confounding factors) was higher with Day 5/6 versus Day 3 transfers (17.2 versus 14.1%, P < 0.001). Using logistic regression analysis to adjust for confounding factors, preterm birth rate <37 weeks was the only outcome significantly increased after Day 5/6 compared with Day 3 transfer (odds ratio 1.32, 95% confidence interval 1.17-1.49). The following confounding factors were adjusted for: year of treatment (2001-2009), maternal age (continuous), parity (0 versus ≥1 birth), diagnosis category, number of oocytes retrieved [≤20 versus >20 (high responder group)], insemination method (IVF versus ICSI), number of embryos transferred (1, 2 or ≥3) and the presence of a vanishing twin (≥1 fetal heart on the initial ultrasonographic examination). Post-natal follow-up studies will be required to determine if this difference we observed translates into adverse long-term effects on these offspring. The rate of early preterm births (<32 weeks) was higher in Day 5/6 versus Day 3, but the low number of cases in this category did not have the power to show a difference (3.0 versus 2.7%, P = 0.34). We found a significantly higher risk of preterm birth (<37 weeks) in singletons after extended embryo culture (Day 5/6) compared with cleavage stage (Day 3) transfer, even when adjusting for confounding factors. Our findings are in agreement with the previous two studies; however, we did not show a difference in the very preterm deliveries (unlike the US study) or in fetal malformations (as in the Swedish study). We hypothesize that there may be a deleterious effect of prolonged in vitro embryo culture on subsequent placentation. Longer term follow-up studies will be required to determine if prolonged in vitro culture to the blastocyst stage has an adverse effect on the long-term health of offspring when compared with shorter cleavage stage culture. None.

Antibiotics for treating bacterial vaginosis in pregnancy.

PubMed

McDonald, H; Brocklehurst, P; Parsons, J

2005-01-25

Bacterial vaginosis is an imbalance of the normal vaginal flora with an overgrowth of anaerobic bacteria and a lack of the normal lactobacillary flora. Bacterial vaginosis during pregnancy has been associated with poor perinatal outcome and, in particular, preterm birth. Identification and treatment may reduce the risk of preterm birth and its consequences. To assess the effects of antibiotic treatment of bacterial vaginosis in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group trials register (May 2004). Randomized trials comparing antibiotic treatment with placebo or no treatment, or comparing two or more antibiotic regimens in pregnant women with bacterial vaginosis or intermediate vaginal flora. Two reviewers assessed trials and extracted data independently. We contacted study authors for additional information. Thirteen trials involving 5300 women were included; all were of good quality. Antibiotic therapy was effective at eradicating bacterial vaginosis during pregnancy (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.19 to 0.24, nine trials of 3895 women). Treatment was not significant in reducing the risk of preterm birth before 37 weeks (OR 0.87, 95% CI 0.74 to 1.03, thirteen trials of 5300 women, and there was significant heterogeneity between trials, p-value 0.002), preterm birth before 34 weeks (OR 1.22, 95% CI 0.67 to 2.19, five trials of 851 women), preterm birth before 32 weeks (OR 1.14, 95% CI 0.76 to 1.70, four trials of 3565 women), or the risk of preterm prelabour rupture of membranes (OR 0.88, 95% CI 0.61 to 1.28, four trials of 2579 women). In women with a previous preterm birth, treatment did not affect the risk of subsequent preterm birth (OR 0.83, 95% CI 0.59 to 1.17, five trials of 622 women, with significant heterogeneity between these trials); however, it may decrease the risk of preterm prelabour rupture of membranes (OR 0.14, 95% CI 0.05 to 0.38, two trials of 114 women, and low birthweight (OR 0.31, 95% CI 0.13 to 0.75, two trials of 114 women). Antibiotic treatment can eradicate bacterial vaginosis in pregnancy. However, this review provides little evidence that screening and treating all pregnant women with asymptomatic bacterial vaginosis will prevent preterm birth and its consequences. For women with a previous preterm birth, there is some suggestion that treatment of bacterial vaginosis may reduce the risk of preterm prelabour rupture of membranes and low birthweight.

Preterm birth time trends in Europe: a study of 19 countries.

PubMed

Zeitlin, J; Szamotulska, K; Drewniak, N; Mohangoo, A D; Chalmers, J; Sakkeus, L; Irgens, L; Gatt, M; Gissler, M; Blondel, B

2013-10-01

To investigate time trends in preterm birth in Europe by multiplicity, gestational age, and onset of delivery. Analysis of aggregate data from routine sources. Nineteen European countries. Live births in 1996, 2000, 2004, and 2008. Annual risk ratios of preterm birth in each country were estimated with year as a continuous variable for all births and by subgroup using log-binomial regression models. Overall preterm birth rate and rate by multiplicity, gestational age group, and spontaneous versus non-spontaneous (induced or prelabour caesarean section) onset of labour. Preterm birth rates rose in most countries, but the magnitude of these increases varied. Rises in the multiple birth rate as well as in the preterm birth rate for multiple births contributed to increases in the overall preterm birth rate. About half of countries experienced no change or decreases in the rates of singleton preterm birth. Where preterm birth rates rose, increases were no more prominent at 35-36 weeks of gestation than at 32-34 weeks of gestation. Variable trends were observed for spontaneous and non-spontaneous preterm births in the 13 countries with mode of onset data; increases were not solely attributed to non-spontaneous preterm births. There was a wide variation in preterm birth trends in European countries. Many countries maintained or reduced rates of singleton preterm birth over the past 15 years, challenging a widespread belief that rising rates are the norm. Understanding these cross-country differences could inform strategies for the prevention of preterm birth. © 2013 The Authors. BJOG: An International Journal of Obstetrics & Gynaecology published by John Wiley and Sons on behalf of the Royal College of Obstetricians and Gynaecologists.

Antibiotics for treating bacterial vaginosis in pregnancy.

PubMed

McDonald, H; Brocklehurst, P; Parsons, J; Vigneswaran, R

2003-01-01

Bacterial vaginosis is an imbalance of the normal vaginal flora with an overgrowth of anaerobic bacteria and a lack of the normal lactobacillary flora. Bacterial vaginosis during pregnancy has been associated with poor perinatal outcome and, in particular, preterm birth. Identification and treatment may reduce the risk of preterm birth and its consequences. To assess the effects of antibiotic treatment of bacterial vaginosis in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group trials register (September 2002). Randomized trials comparing antibiotic treatment with placebo or no treatment, or comparing two or more antibiotic regimens in pregnant women with bacterial vaginosis. Two reviewers assessed trials and extracted data independently. Study authors were contacted for additional information. Ten trials involving 4249 women were included; all were of good quality. Antibiotic therapy was effective at eradicating bacterial vaginosis during pregnancy (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.18 to 0.24, eight trials of 3825 women). Treatment did not significantly reduce the risk of preterm birth before 37 weeks (OR 0.95, 95% CI 0.82 to 1.10, eight trials of 4062 women), 34 weeks (OR 1.20, 95% CI 0.69 to 2.07, five trials of 851 women), or 32 weeks (OR 1.08, 95% CI 0.70 to 1.68, three trials of 3080 women). However, antibiotic treatment did significantly decrease the risk of preterm prelabour rupture of membranes (OR 0.32, 95% CI 0.15 to 0.67, three trials of 562 women). In women with a previous preterm birth, treatment did not affect the risk of subsequent preterm birth (OR 0.83, 95% CI 0.59 to 1.17, five trials of 622 women) but it did decrease the risk of preterm prelabour rupture of membranes (OR 0.14, 95% CI 0.05 to 0.38, two trials of 114 women) and low birthweight (OR 0.31, 95% CI 0.13 to 0.75, five trials of 622 women). Antibiotic treatment can eradicate bacterial vaginosis in pregnancy. However, the current evidence does not support screening and treating all pregnant women with asymptomatic bacterial vaginosis to prevent preterm birth and its consequences. For women with a previous preterm birth, there is little suggestion that detection and treatment of bacterial vaginosis will prevent a further preterm birth, but it may reduce the risk of low birthweight and preterm prelabour rupture of membranes.

Trial protocol OPPTIMUM– Does progesterone prophylaxis for the prevention of preterm labour improve outcome?

PubMed Central

2012-01-01

Background Preterm birth is a global problem, with a prevalence of 8 to 12% depending on location. Several large trials and systematic reviews have shown progestogens to be effective in preventing or delaying preterm birth in selected high risk women with a singleton pregnancy (including those with a short cervix or previous preterm birth). Although an improvement in short term neonatal outcomes has been shown in some trials these have not consistently been confirmed in meta-analyses. Additionally data on longer term outcomes is limited to a single trial where no difference in outcomes was demonstrated at four years of age of the child, despite those in the “progesterone” group having a lower incidence of preterm birth. Methods/Design The OPPTIMUM study is a double blind randomized placebo controlled trial to determine whether progesterone prophylaxis to prevent preterm birth has long term neonatal or infant benefit. Specifically it will study whether, in women with singleton pregnancy and at high risk of preterm labour, prophylactic vaginal natural progesterone, 200 mg daily from 22 – 34 weeks gestation, compared to placebo, improves obstetric outcome by lengthening pregnancy thus reducing the incidence of preterm delivery (before 34 weeks), improves neonatal outcome by reducing a composite of death and major morbidity, and leads to improved childhood cognitive and neurosensory outcomes at two years of age. Recruitment began in 2009 and is scheduled to close in Spring 2013. As of May 2012, over 800 women had been randomized in 60 sites. Discussion OPPTIMUM will provide further evidence on the effectiveness of vaginal progesterone for prevention of preterm birth and improvement of neonatal outcomes in selected groups of women with singleton pregnancy at high risk of preterm birth. Additionally it will determine whether any reduction in the incidence of preterm birth is accompanied by improved childhood outcome. Trial registration ISRCTN14568373 PMID:22866909

Risk assessment and management to prevent preterm birth.

PubMed

Koullali, B; Oudijk, M A; Nijman, T A J; Mol, B W J; Pajkrt, E

2016-04-01

Preterm birth is the most important cause of neonatal mortality and morbidity worldwide. In this review, we review potential risk factors associated with preterm birth and the subsequent management to prevent preterm birth in low and high risk women with a singleton or multiple pregnancy. A history of preterm birth is considered the most important risk factor for preterm birth in subsequent pregnancy. General risk factors with a much lower impact include ethnicity, low socio-economic status, maternal weight, smoking, and periodontal status. Pregnancy-related characteristics, including bacterial vaginosis and asymptomatic bacteriuria, appear to be of limited value in the prediction of preterm birth. By contrast, a mid-pregnancy cervical length measurement is independently associated with preterm birth and could be used to identify women at risk of a premature delivery. A fetal fibronectin test may be of additional value in the prediction of preterm birth. The most effective methods to prevent preterm birth depend on the obstetric history, which makes the identification of women at risk of preterm birth an important task for clinical care providers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Institutional racism, neighborhood factors, stress, and preterm birth.

PubMed

Mendez, Dara D; Hogan, Vijaya K; Culhane, Jennifer F

2014-01-01

Racial/ethnic disparities in the risk of preterm birth may be explained by various factors, and previous studies are limited in examining the role of institutional racism. This study focused on the following questions: what is the association between preterm birth and institutional racism as measured by residential racial segregation (geographic separation by race) and redlining (black-white disparity in mortgage loan denial); and what is the association between preterm birth and reported stress, discrimination, and neighborhood quality. We used data from a clinic-based sample of pregnant women (n = 3462) participating in a stress and pregnancy study conducted from 1999 to 2004 in Philadelphia, PA (USA). We linked data from the 2000 US Census and Home Mortgage Disclosure Act (HMDA) data from 1999 to 2004 and developed measures of residential redlining and segregation. Among the entire population, there was an increased risk for preterm birth among women who were older, unmarried, tobacco users, higher number of previous births, high levels of experiences of everyday discrimination, owned their homes, lived in nonredlined areas, and areas with high levels of segregation measured by the isolation index. Among black women, living in a redlined area (where blacks were more likely to be denied mortgage loans compared to whites) was moderately associated with a decreased risk of preterm birth (aRR = 0.8, 95% CI: 0.6, 0.99). Residential redlining as a form institutional racism and neighborhood characteristic may be important for understanding racial/ethnic disparities in pregnancy and preterm birth.

In vivo T-cell activation by a monoclonal αCD3ε antibody induces preterm labor and birth

PubMed Central

Gomez-Lopez, Nardhy; Romero, Roberto; Arenas-Hernandez, Marcia; Ahn, Hyunyoung; Panaitescu, Bogdan; Vadillo-Ortega, Felipe; Sanchez-Torres, Carmen; Salisbury, Katherine S; Hassan, Sonia S.

2016-01-01

PROBLEM Activated/effector T cells seem to play a role in the pathological inflammation associated with preterm labor. The aim of this study was to determine whether in vivo T-cell activation by a monoclonal αCD3ε antibody induces preterm labor and birth. METHOD OF STUDY Pregnant B6 mice were intraperitoneally injected with a monoclonal αCD3ε antibody or its isotype control. The gestational age and the rates of preterm birth and pup mortality at birth, as well as the fetal heart rate and umbilical artery pulsatility index, were determined. RESULTS Injection of a monoclonal αCD3ε antibody led to preterm labor/birth [αCD3ε 83 ± 16.97% (10/12) vs. isotype 0% (0/8)], and increased the rate of pup mortality at birth [αCD3ε 87.30 ± 8.95% (77/85) vs. isotype 4.91 ± 4.34% (3/59)]. In addition, injection of a monoclonal αCD3ε antibody decreased the fetal heart rate and increased the umbilical artery pulsatility index when compared to isotype controls. CONCLUSION In vivo T-cell activation by a monoclonal αCD3ε antibody in late gestation induces preterm labor and birth. PMID:27658719

Perinatal Risks in "Late Motherhood" Defined Based On Parity and Preterm Birth Rate - an Analysis of the German Perinatal Survey (20th Communication).

PubMed

Schure, V; Voigt, M; Schild, R L; Hesse, V; Carstensen, M; Schneider, K T M; Straube, S

2012-01-01

Aim: "Late motherhood" is associated with greater perinatal risks but the term lacks precise definition. We present an approach to determine what "late motherhood" associated with "high risk" is, based on parity and preterm birth rate. Materials and Methods: Using data from the German Perinatal Survey of 1998-2000 we analysed preterm birth rates in women with zero, one, or two previous live births. We compared groups of "late" mothers (with high preterm birth rates) with "control" groups of younger women (with relatively low preterm birth rates). Data of 208 342 women were analysed. For women with zero (one; two) previous live births, the "control" group included women aged 22-26 (27-31; 29-33) years. Women in the "late motherhood" group were aged > 33 (> 35; > 38) years. Results: The "late motherhood" groups defined in this way were also at higher risk of adverse perinatal events other than preterm birth. For women with zero (one; two) previous live births, normal cephalic presentation occurred in 89 % (92.7 %; 93.3 %) in the "control" group, but only in 84.5 % (90 %; 90.4 %) in the "late motherhood" group. The mode of delivery was spontaneous or at most requiring manual help in 71.3 % (83.4 %; 85.8 %) in the "control" group, but only in 51.4 % (72.2 %; 76.4 %) in the "late motherhood" group. Five-minute APGAR scores were likewise worse for neonates of "late" mothers and the proportion with a birth weight ≤ 2499 g was greater. Conclusion: "Late motherhood" that is associated with greater perinatal risks can be defined based on parity and preterm birth rate.

Role of perceived stress in the occurrence of preterm labor and preterm birth among urban women.

PubMed

Seravalli, Laura; Patterson, Freda; Nelson, Deborah B

2014-01-01

This study examined whether prenatal perceived stress levels during pregnancy were associated with preterm labor or preterm birth. Perceived stress levels were measured at 16 weeks' gestation or less and between 20 and 24 weeks' gestation in a sample of 1069 low-income pregnant women attending Temple University prenatal care clinics. Scores were averaged to create a single measure of prenatal stress. Preterm birth was defined as the occurrence of a spontaneous birth prior to 37 weeks' gestation. Preterm labor was defined as the occurrence of regular contractions between 20 and 37 weeks' gestation that were associated with changes in the cervix. Independent of potential confounding factors, prenatal perceived stress was not associated with preterm labor (odds ratio [OR], 1.10; 95% confidence interval [CI], 0.69-1.78; P = .66); however, prenatal stress trended toward an association with preterm birth (OR, 1.49; 95% CI, 1.00-2.23; P = .05). The strongest predictor of preterm labor was a history of preterm labor in a prior pregnancy. Women with a history of preterm labor were 2 times more likely to experience preterm labor in the current pregnancy than women who did not have a preterm labor history (OR, 2.16; 95% CI, 1.05-4.41; P = .04). Historical risk factors for preterm birth, such as African American race, a history of abortion, or a history of preterm birth, were not related to preterm labor. The strongest predictor of preterm birth was having a history of preterm birth in a prior pregnancy (OR, 2.55; 95% CI, 1.54-4.24; P < .001). Prenatal perceived stress levels may be a risk factor for preterm birth independent of preterm labor; however, prenatal stress was not associated with preterm labor. Risk factors for preterm labor may be different from those of preterm birth. © 2014 by the American College of Nurse-Midwives.

Care for women with prior preterm birth.

PubMed

Iams, Jay D; Berghella, Vincenzo

2010-08-01

Women who have delivered an infant between 16 and 36 weeks' gestation have an increased risk of preterm birth in subsequent pregnancies. The risk increases with more than 1 preterm birth and is inversely proportional to the gestational age of the previous preterm birth. African American women have rates of recurrent preterm birth that are nearly twice that of women of other backgrounds. An approximate risk of recurrent preterm birth can be estimated by a comprehensive reproductive history, with emphasis on maternal race, the number and gestational age of prior births, and the sequence of events preceding the index preterm birth. Interventions including smoking cessation, eradication of asymptomatic bacteriuria, progestational agents, and cervical cerclage can reduce the risk of recurrent preterm birth when employed appropriately. Copyright (c) 2010 Mosby, Inc. All rights reserved.

Age-specific preterm birth rates after exclusion of risk factors--an analysis of the german perinatal survey.

PubMed

Voigt, M; Briese, V; Carstensen, M; Wolterdorf, F; Hallier, E; Straube, S

2010-08-01

A description of preterm birth rates - specified according to maternal age - after the exclusion of anamnestic risk factors. Data for this study were taken from the German Perinatal Survey of 1998-2000. We analysed data from 492,576 singleton pregnancies and determined preterm birth rates according to maternal age after a stepwise exclusion of anamnestic risk factors. There was a U-shaped dependence of preterm birth rates on maternal age. The lowest preterm birth rate (without excluding women with anamnestic risk factors) was 5.6% at a maternal age of 29 years. The prevalence of some anamnestic risk factors for preterm birth, such as previous stillbirths, spontaneous and induced abortions, and ectopic pregnancies, increased with maternal age. Excluding women with anamnestic risk factors lowered the preterm birth rates substantially. The lowest preterm birth rates were found in women with one previous live birth, without any anamnestic risk factors, and with a body mass index (BMI) of 25.00-29.99. With these restrictions, we found preterm birth rates of under 2% for women aged 24-31 years. The magnitude and age-dependence of the preterm birth rate can to some extent be explained with the age-dependent prevalence of anamnestic risk factors for preterm birth. Excluding women with anamnestic risk factors from our study population lowered the preterm birth rates substantially. © Georg Thieme Verlag KG Stuttgart · New York.

BLACK PRETERM BIRTH RISK IN NON-BLACK NEIGHBORHOODS: EFFECTS OF HISPANIC, ASIAN, AND NON-HISPANIC WHITE ETHNIC DENSITIES

PubMed Central

Mason, Susan M.; Kaufman, Jay S.; Daniels, Julie L.; Emch, Michael E.; Hogan, Vijaya K.; Savitz, David A.

2013-01-01

Purpose Studies of ethnic density and health in the United States have documented poorer health outcomes in black compared to non-black neighborhoods, but few studies have considered the identities of the non-black populations. Methods New York City birth records from 1995 through 2003 and a spatial measure of ethnic density were used to examine preterm birth risks among non-Hispanic black women associated with non-Hispanic white, Hispanic, Asian, and non-Hispanic black neighborhood densities. Logistic regression models were used to estimate the effect on black preterm birth risks of replacing white neighbors with Hispanic, Asian, and black neighbors. Risk differences were computed for changes from the 10th to the 90th percentiles of ethnic density. Results Increasing Hispanic density was associated with reduced preterm birth risks among non-Hispanic black women, especially if the black women were foreign-born (RD=−19.1 per 1,000 births; 95% CI: −28.6, −9.5). Estimates for increasing Asian density were null. Increasing black density was associated with increasing black preterm birth risk, with a threshold at higher levels of black density. Conclusions The low risks of preterm birth among foreign-born non-Hispanic black women in majority-Hispanic neighborhoods may be related to protective psychosocial or nutritional factors in Hispanic neighborhoods. PMID:21737050

Small-for-gestational age and preterm birth across generations: a population-based study of Illinois births.

PubMed

Castrillio, Stephanie M; Rankin, Kristin M; David, Richard J; Collins, James W

2014-12-01

Small for gestational age (weight for gestational age <10th percentile, SGA) and preterm birth (<37 weeks, PTB) are the major determinants of infant mortality rates and racial disparities therein. To determine the generational inheritance patterns of SGA and PTB among non-Hispanic Whites and African-Americans. Stratified and multivariable binominal regression analyses were performed on an Illinois transgenerational dataset of White and African-American infants (1989-1991) and their mothers (1956-1976) with appended US census income information. Former SGA White mothers (N = 8,993) had a twofold greater infant SGA frequency than former non-SGA White mothers (N = 101,312); 14.4 versus 6.9 %, RR = 2.1 (2.0-2.2). Former SGA African American (N = 4,861) mothers had a SGA birth frequency of 25.7 % compared to 16.1 % for former non-SGA mothers (N = 28,090); RR = 1.5 (1.5-1.6). The adjusted (controlling for maternal age, education, marital status, parity, prenatal care usage, cigarette smoking, and hypertension) RR (95 % CI) of infant SGA for former SGA (compared to non-SGA) White and African-American mothers equaled 2.0 (1.9-2.1 and 1.5 (1.5-1.6), respectively. The adjusted RR (95 % CI) of infant preterm birth for former preterm (compared to term) White and African-American mothers were 1.1 (1.0-1.2). The findings were minimally changed among mothers with a lifelong residence in impoverished or affluent neighborhoods. In both races, approximately 8 % of SGA births were attributable to maternal SGA. There is a transgenerational association of SGA but not preterm birth among non-Hispanic Whites and African-Americans. In both races, a similar proportion of SGA births are attributable to maternal SGA.

Effects of socioeconomic position and clinical risk factors on spontaneous and iatrogenic preterm birth

PubMed Central

2014-01-01

Background The literature shows a variable and inconsistent relationship between socioeconomic position and preterm birth. We examined risk factors for spontaneous and iatrogenic preterm birth, with a focus on socioeconomic position and clinical risk factors, in order to explain the observed inconsistency. Methods We carried out a retrospective population-based cohort study of all singleton deliveries in Nova Scotia from 1988 to 2003. Data were obtained from the Nova Scotia Atlee Perinatal Database and the federal income tax T1 Family Files. Separate logistic models were used to quantify the association between socioeconomic position, clinical risk factors and spontaneous preterm birth and iatrogenic preterm birth. Results The study population included 132,714 singleton deliveries and the rate of preterm birth was 5.5%. Preterm birth rates were significantly higher among the women in the lowest (versus the highest) family income group for spontaneous (rate ratio 1.14, 95% confidence interval (CI) 1.03, 1.25) but not iatrogenic preterm birth (rate ratio 0.95, 95% CI 0.75, 1.19). Adjustment for maternal characteristics attenuated the family income-spontaneous preterm birth relationship but strengthened the relationship with iatrogenic preterm birth. Clinical risk factors such as hypertension were differentially associated with spontaneous (rate ratio 3.92, 95% CI 3.47, 4.44) and iatrogenic preterm (rate ratio 14.1, 95% CI 11.4, 17.4) but factors such as diabetes mellitus were not (rate ratio 4.38, 95% CI 3.21, 5.99 for spontaneous and 4.02, 95% CI 2.07, 7.80 for iatrogenic preterm birth). Conclusions Socioeconomic position and clinical risk factors have different effects on spontaneous and iatrogenic preterm. Recent temporal increases in iatrogenic preterm birth appear to be responsible for the inconsistent relationship between socioeconomic position and preterm birth. PMID:24670050

Effects of socioeconomic position and clinical risk factors on spontaneous and iatrogenic preterm birth.

PubMed

Joseph, K S; Fahey, John; Shankardass, Ketan; Allen, Victoria M; O'Campo, Patricia; Dodds, Linda; Liston, Robert M; Allen, Alexander C

2014-03-27

The literature shows a variable and inconsistent relationship between socioeconomic position and preterm birth. We examined risk factors for spontaneous and iatrogenic preterm birth, with a focus on socioeconomic position and clinical risk factors, in order to explain the observed inconsistency. We carried out a retrospective population-based cohort study of all singleton deliveries in Nova Scotia from 1988 to 2003. Data were obtained from the Nova Scotia Atlee Perinatal Database and the federal income tax T1 Family Files. Separate logistic models were used to quantify the association between socioeconomic position, clinical risk factors and spontaneous preterm birth and iatrogenic preterm birth. The study population included 132,714 singleton deliveries and the rate of preterm birth was 5.5%. Preterm birth rates were significantly higher among the women in the lowest (versus the highest) family income group for spontaneous (rate ratio 1.14, 95% confidence interval (CI) 1.03, 1.25) but not iatrogenic preterm birth (rate ratio 0.95, 95% CI 0.75, 1.19). Adjustment for maternal characteristics attenuated the family income-spontaneous preterm birth relationship but strengthened the relationship with iatrogenic preterm birth. Clinical risk factors such as hypertension were differentially associated with spontaneous (rate ratio 3.92, 95% CI 3.47, 4.44) and iatrogenic preterm (rate ratio 14.1, 95% CI 11.4, 17.4) but factors such as diabetes mellitus were not (rate ratio 4.38, 95% CI 3.21, 5.99 for spontaneous and 4.02, 95% CI 2.07, 7.80 for iatrogenic preterm birth). Socioeconomic position and clinical risk factors have different effects on spontaneous and iatrogenic preterm. Recent temporal increases in iatrogenic preterm birth appear to be responsible for the inconsistent relationship between socioeconomic position and preterm birth.

Predicting preeclampsia from a history of preterm birth.

PubMed

Rasmussen, Svein; Ebbing, Cathrine; Irgens, Lorentz M

2017-01-01

To assess whether women with a history of preterm birth, independent on the presence of prelabour rupture of the membranes (PROM) and growth deviation of the newborn, are more likely to develop preeclampsia with preterm or preterm birth in a subsequent pregnancy. We conducted a population-based cohort study, based on Medical Birth Registry of Norway between 1967 and 2012, including 742,980 women with singleton pregnancies who were followed up from their 1st to 2nd pregnancy. In the analyses we included 712,511 women after excluding 30,469 women with preeclampsia in the first pregnancy. After preterm birth without preeclampsia in the first pregnancy, the risk of preterm preeclampsia in the second pregnancy was 4-7 fold higher than after term birth (odds ratios 3.5; 95% confidence interval (CI) 3.0-4.0 to 6.5; 95% CI 5.1-8.2). The risk of term preeclampsia in the pregnancy following a preterm birth was 2-3 times higher than after term birth (odds ratios 1.6; 95% CI 1.5-1.8 to 2.6; 95% CI 2.0-3.4). After spontaneous non-PROM preterm birth and preterm PROM, the risk of preterm preeclampsia was 3.3-3.6 fold higher than after spontaneous term birth. Corresponding risks of term preeclampsia was 1.6-1.8 fold higher. No significant time trends were found in the effect of spontaneous preterm birth in the first pregnancy on preterm or term preeclampsia in the second pregnancy. The results suggest that preterm birth, regardless of the presence of PROM, and preeclampsia share pathophysiologic mechanisms. These mechanisms may cause preterm birth in one pregnancy and preeclampsia in a subsequent pregnancy in the same woman. The association was particularly evident with preterm preeclampsia.

An M1-like macrophage polarization in decidual tissue during spontaneous preterm labor that is attenuated by rosiglitazone treatment1

PubMed Central

Kadam, Leena; Mial, Tara N.; Plazyo, Olesya; Garcia-Flores, Valeria; Hassan, Sonia S.; Xu, Zhonghui; Tarca, Adi L.; Drewlo, Sascha; Gomez-Lopez, Nardhy

2016-01-01

Macrophages are implicated in the local inflammatory response that accompanies spontaneous preterm labor/birth; however, their role is poorly understood. We hypothesized that decidual macrophages undergo an M1 polarization during spontaneous preterm labor and that PPARγ activation via rosiglitazone would attenuate the macrophage-mediated inflammatory response, preventing preterm birth. Herein, we show that: 1) decidual macrophages undergo an M1-like polarization during spontaneous term and preterm labor; 2) M2-like macrophages are more abundant than M1-like macrophages in decidual tissue; 3) decidual M2-like macrophages are reduced in preterm pregnancies compared to term pregnancies, regardless of the presence of labor; 4) decidual macrophages express high levels of TNF and IL12, but low levels of PPARγ, during spontaneous preterm labor; 5) decidual macrophages from women who underwent spontaneous preterm labor display plasticity by M1↔M2 polarization in vitro; 6) incubation with rosiglitazone reduces the expression of TNF and IL12 in decidual macrophages from women who underwent spontaneous preterm labor; and 7) treatment with rosiglitazone reduces the rate of LPS-induced preterm birth and improves neonatal outcomes by reducing the systemic pro-inflammatory response in B6 mice and down-regulating mRNA and protein expression of NFκB, TNF, and IL10 in decidual and myometrial macrophages. In summary, we demonstrated that decidual M1-like macrophages are associated with spontaneous preterm labor, and that PPARγ activation via rosiglitazone can attenuate the macrophage-mediated pro-inflammatory response, preventing preterm birth and improving neonatal outcomes. These findings suggest that the PPARγ pathway is a new molecular target for future preventative strategies for spontaneous preterm labor/birth. PMID:26889045

Attitudes of Swedish midwives towards management of extremely preterm labour and birth.

PubMed

Danerek, Margaretha; Maršál, Karel; Cuttini, Marina; Lingman, Göran; Nilstun, Tore; Dykes, Anna-Karin

2012-12-01

the aim of the study was to ascertain the attitudes of Swedish midwives towards management of very preterm labour and birth and to compare the attitudes of midwives at university hospitals with those at general hospitals. this cross-sectional descriptive and comparative study used an anonymous self-administrated questionnaire for data collection. Descriptive and analytic statistics were carried out for analysis. the answers from midwives (n=259) were collected in a prospective SWEMID study. the midwives had experience of working on delivery wards in maternity units with neonatal intensive care units (NICU) in Sweden. in the management of very preterm labour and birth, midwives agreed to initiate interventions concerning steroid prophylaxis at 23 gestational weeks (GW), caesarean section for preterm labour only at 25 GW, when to give information to the neonatologist before birth at 23 GW, and when to suggest transfer to NICU at 23 GW. Midwives at university hospitals were prone to start interventions at an earlier gestational age than the midwives at general hospitals. Midwives at university hospitals seemed to be more willing to disclose information to the parents. midwives with experience of handling very preterm births at 21-28 GW develop a positive attitude to interventions at an earlier gestational age as compared to midwives without such experience. based on these results we suggest more communication and transfer of information about the advances in perinatal care and exchange of knowledge between the staff at general and university hospitals. Establishment of platforms for inter-professional discussions about ethically difficult situations in perinatal care, might benefit the management of very preterm labour and birth. Copyright © 2011 Elsevier Ltd. All rights reserved.

The HPTN 024 Study: the efficacy of antibiotics to prevent chorioamnionitis and preterm birth.

PubMed

Goldenberg, Robert L; Mwatha, Anthony; Read, Jennifer S; Adeniyi-Jones, Samuel; Sinkala, Moses; Msmanga, Gernard; Martinson, Francis; Hoffman, Irving; Fawzi, Wafaie; Valentine, Megan; Emel, Lynda; Brown, Elizabeth; Mudenda, Victor; Taha, Taha E

2006-03-01

The use of antibiotics to prevent preterm birth has achieved mixed results. Our goal in this study was to determine if antibiotics given prenatally and during labor reduce the incidence of preterm birth and histologic chorioamnionitis. A double-blind randomized placebo-controlled trial of antibiotics to reduce preterm birth was conducted in 4 African sites. Both HIV-infected and uninfected pregnant women were given 2 courses of antibiotics, prenatally at 24 weeks (metronidazole 250 mg and erythromycin 250 mg tid orally for 7 days), and during labor (metronidazole 250 mg and ampicillin 500 mg q 4 hours) or identically appearing placebos. Two thousand ninety-eight HIV-infected and 335 HIV-uninfected women had evaluable end points, including gestational age determined by both obstetric and pediatric criteria and birth weight (BWT). Pre- and post-treatment rates of various sexually transmitted infections (STI) were determined and placentas were evaluated for histologic chorioamnionitis. Comparing antibiotic versus placebo treated HIV-infected and uninfected women, there were few differences in mean gestational age at delivery, the percent of preterm births, the time between randomization and delivery, or BWT. Four weeks after the 24-week antibiotic/placebo course, bacterial vaginosis, and trichomoniasis were reduced by 49% to 61% in the antibiotic groups compared with the placebo groups. However, in both the HIV-infected and uninfected groups, the placentas showed no difference in the rate of histologic chorioamnionitis. There were significant differences between HIV-infected and uninfected women, with the former having less education, a history of more stillbirths, more STIs, and in this pregnancy, a lower BWT (2949 vs 3100 g, P < .0001). Despite reducing the rate of vaginal infections, the antibiotic regimen used in this study did not reduce the rate of preterm birth, increase the time to delivery, or increase BWT. Failure of this regimen to reduce the rate of histologic chorioamnionitis may explain the reason the antibiotics failed to reduce preterm birth.

[Clinical evaluation of periodontium in pregnant women with risk of preterm birth].

PubMed

Kurnatowska, Anna; Stankiewicz, Anna

2006-05-01

The aim of the study was to evaluate condition of the periodontium in pregnant women with pathological progress of the pregnancy, clinically and to compare it to periodontium in pregnant women in good health. Over the last years, the studies have described that periodontitis caused by dental plaque, could be the risk factor for preterm birth and low birth weight. This study was performed in 80 pregnant women, 40 with pathologic pregnancy and 40 with normal pregnancy in it. Periodontal Indexes were used to evaluate periodontium. In the searching group gingivitis gravidarum haemorrhagica diffusa and hyperplastica generalisata were dominating. In the control group gingivitis gravidatum simplex and hyperplastica localisata were observed. More severe manifestation of gingivitis gravidarum was noticed in pregnant women with risk of preterm low birth. We did not prove correlation between amount of bacterial dental plaque in pregnant women and risk of preterm low birth weight.

Maternal age and preterm births in singleton and twin pregnancies conceived by in vitro fertilisation in the United States.

PubMed

Xiong, Xu; Dickey, Richard P; Pridjian, Gabriella; Buekens, Pierre

2015-01-01

Among natural conceptions, advanced maternal age (≥ 35 years) is associated with an increased risk of preterm birth. However, few studies have specifically examined this association in births resulting from in vitro fertilisation (IVF). A retrospective cohort study was conducted in 97288 singleton and 40961 twin pregnancies resulting from fresh non-donor IVF cycles using 2006-10 data from the Society for Assisted Reproductive Technology Clinic Online Reporting System. Rates of very early preterm (<28), early preterm (<32), and preterm birth (<37 completed weeks) decreased with increasing maternal age in both singleton and twin births (PTrend <0.01). With women aged 30-34 years as the reference, those aged <30 years were at an increased risk of all types of preterm births. The adjusted odd ratio (95% confidence interval [CI]) for very early preterm birth, early preterm birth, and preterm birth in women aged 25-29 years were 1.3 [95% CI 1.1, 1.5], 1.2 [95% CI 1.1, 1.4], and 1.1 [95% CI 1.02, 1.2] in singletons. This increased risk of preterm births among younger women was even more significant in twin births. However, women aged ≥ 35 years were not at an increased risk of any type of preterm births in both singleton and twin births. In contrast to natural conception, advanced maternal age is not associated with an increased risk of preterm births in pregnancies conceived by IVF. Women who seek IVF treatments before 30 years old are at higher risk of all stages of preterm births. © 2014 John Wiley & Sons Ltd.

Birth Outcomes after the Fukushima Daiichi Nuclear Power Plant Disaster: A Long-Term Retrospective Study

PubMed Central

Leppold, Claire; Nomura, Shuhei; Sawano, Toyoaki; Ozaki, Akihiko; Tsubokura, Masaharu; Hill, Sarah; Kanazawa, Yukio; Anbe, Hiroshi

2017-01-01

Changes in population birth outcomes, including increases in low birthweight or preterm births, have been documented after natural and manmade disasters. However, information is limited following the 2011 Fukushima Daiichi Nuclear Power Plant Disaster. In this study, we assessed whether there were long-term changes in birth outcomes post-disaster, compared to pre-disaster data, and whether residential area and food purchasing patterns, as proxy measurements of evacuation and radiation-related anxiety, were associated with post-disaster birth outcomes. Maternal and perinatal data were retrospectively collected for all live singleton births at a public hospital, located 23 km from the power plant, from 2008 to 2015. Proportions of low birthweight (<2500 g at birth) and preterm births (<37 weeks gestation at birth) were compared pre- and post-disaster, and regression models were conducted to assess for associations between these outcomes and evacuation and food avoidance. A total of 1101 live singleton births were included. There were no increased proportions of low birthweight or preterm births in any year after the disaster (merged post-disaster risk ratio of low birthweight birth: 0.98, 95% confidence interval (CI): 0.64–1.51; and preterm birth: 0.68, 95% CI: 0.38–1.21). No significant associations between birth outcomes and residential area or food purchasing patterns were identified, after adjustment for covariates. In conclusion, no changes in birth outcomes were found in this institution-based investigation after the Fukushima disaster. Further research is needed on the pathways that may exacerbate or reduce disaster effects on maternal and perinatal health. PMID:28534840

Affordability of programmes to prevent spontaneous preterm birth in Austria: a budget impact analysis.

PubMed

Zechmeister-Koss, Ingrid; Piso, Brigitte

2014-02-01

Preterm birth is a rising health problem in Europe generally, and in Austria specifically. Decision makers require objective information on the effects and costs of measures to prevent preterm birth. We undertook a budget impact analysis from a public payer perspective and for a 1-year and 5-year time horizon for five prevention approaches to reduce preterm birth. These were cervix screening + progesterone application, progesterone injection, smoking cessation, fish oil supplementation and infection screening. We analysed affordability in terms of programme costs and potential cost savings. Programme costs range from below €50 000 (cervix screening in high-risk pregnancy) to €500 000 (universal infection screening). The lowest health effects have been shown for smoking cessation programmes (-10 preterm births per year), whereas infection screening demonstrated the largest effect (-230 preterm births per year). In the base-case analysis, all programmes are potentially cost saving (-€500 000 to -€13 million per year). In the sensitivity analyses, preterm birth costs, target group size and (partly) unit costs of programme components have an influence on potential cost savings. However, except for two programmes, the results are robust concerning an overall economic net benefit of the programmes analysed compared with no programme. The study is mainly limited by the quality of some cost data and choice of the reference scenario. When considering potential cost savings, the five prevention programmes analysed seem affordable, with cervix screening and infection screening likely being the most promising in Austria.

Lung parenchyma at maturity is influenced by postnatal growth but not by moderate preterm birth in sheep.

PubMed

Maritz, Gert; Probyn, Megan; De Matteo, Robert; Snibson, Ken; Harding, Richard

2008-01-01

We have recently shown that moderate preterm birth, in the absence of respiratory support, altered the structure of lung parenchyma in young lambs, but the long-term effects are unknown. To determine whether structural changes persist to maturity, and whether postnatal growth affects lung structure at maturity in sheep. At approximately 1.2 years after birth, lung parenchyma of sheep born 14 days before term (n = 7) was stereologically compared with that of controls born at term (n = 8, term approx. 146 days). Preterm birth per se had no significant effect on lung volume, alveolar number and size, and thicknesses of the alveolar walls and blood-gas barrier. After combining the preterm and term groups, we examined the effects of postnatal growth rates on lung parenchyma. Slower-growing sheep (SG; n = 7: 4 preterm, 3 term) were compared with faster-growing sheep (FG; n = 8: 3 preterm, 5 term). At approximately 1.2 years, the right lung volume, relative to body weight, was significantly lower in SG than FG sheep (p < 0.05) and alveolar number was significantly lower by approximately 44%. The total alveolar internal surface area of the right lung of SG sheep was 38% smaller than in FG sheep; it was also significantly lower when related to both lung and body weight. Our data suggest that moderate preterm birth does not cause persistent alterations in lung parenchyma. However, slow postnatal growth in low-birth-weight sheep results in smaller lungs with fewer alveoli and a lower alveolar surface area relative to body weight. Copyright (c) 2007 S. Karger AG, Basel.

Rethinking Stress in Parents of Preterm Infants: A Meta-Analysis

PubMed Central

Schappin, Renske; Wijnroks, Lex; Uniken Venema, Monica M. A. T.; Jongmans, Marian J.

2013-01-01

Background With improved medical outcome in preterm infants, the psychosocial situation of their families is receiving increasing attention. For parents, the birth of a preterm infant is generally regarded as a stressful experience, and therefore many interventions are based on reducing parental stress. Nevertheless, it remains unclear whether parents of children born preterm experience more stress than parents of term-born children, which would justify these interventions. This meta-analysis provides a comprehensive account of parental stress in parents of preterm infants, from birth of the infant through to their adolescence. Mean levels of stress in specific domains of family functioning were investigated, and stress levels in parents of preterm and term infants, and fathers and mothers of preterm infants, were compared. Furthermore, we investigated moderators of parental stress. Methods and Findings A random-effects meta-analysis was conducted including 38 studies describing 3025 parents of preterm (<37 wk) and low birth weight (<2500 g) infants. Parental stress was measured with two parent-reported questionnaires, the Parenting Stress Index and the Parental Stressor Scale: Neonatal Intensive Care Unit. The results indicate that parents of preterm-born children experience only slightly more stress than parents of term-born children, with small effect sizes. Furthermore, mothers have slightly more stress than fathers, but these effect sizes are also small. Parents report more stress for infants with lower gestational ages and lower birth weights. There is a strong effect for infant birth year, with decreasing parental stress from the 1980s onward, probably due to increased quality of care for preterm infants. Conclusions Based on our findings we argue that prematurity can best be regarded as one of the possible complications of birth, and not as a source of stress in itself. PMID:23405105

Center variation in the delivery of indicated late preterm births

PubMed Central

Aliaga, Sofia; Zhang, Jun; Long, D. Leann; Herring, Amy H.; Laughon, Matthew; Boggess, Kim; Reddy, Uma M.; Grantz, Katherine Laughon

2016-01-01

Objective Evidence for optimal timing of delivery for some pregnancy complications at late preterm gestation is limited. The purpose of this study was to identify center variation of indicated late preterm births. Study design Analysis of singleton late preterm and term births from a large U.S. retrospective obstetrical cohort. Births associated with spontaneous preterm labor, major congenital anomalies, chorioamnionitis, and emergency cesarean were excluded. We used modified Poisson fixed effects logistic regression with interaction terms to assess center variation of indicated late preterm births associated with four medical/obstetric comorbidities after adjusting for socio-demographics, co-morbidities, and hospital/provider characteristics. Results We identified 150,055 births from 16 hospitals; 9218 were indicated late preterm births. We found wide variation of indicated late preterm births across hospitals. The extent of center variation was greater for births associated with preterm premature rupture of membranes (RR across sites: 0.45 – 3.05), hypertensive disorders of pregnancy (RR across sites: 0.36 – 1.27), and placenta previa/abruption (RR across sites: 0.48 – 1.82). We found less center variation for births associated with diabetes (RR across sites: 0.65 – 1.39). Conclusion Practice variation in the management of indicated late preterm deliveries might be a source of preventable late preterm birth. PMID:27120474

A comparison of risk assessment models for term and preterm low birthweight.

PubMed

Michielutte, R; Ernest, J M; Moore, M L; Meis, P J; Sharp, P C; Wells, H B; Buescher, P A

1992-01-01

Most epidemiological research dealing with the assessment of risk for low birthweight has focused on all low birthweight births. Studies that have attempted to distinguish between term and preterm low birthweights have tended to examine preterm low birthweight, since the risk of perinatal mortality and morbidity is greatest for this group of infants. This study uses data from 25,408 singleton births in a 20-county region in North Carolina to identify and compare risk factors for term and preterm low birthweights, and also examines the usefulness of separate multivariate risk assessment systems for term and preterm low birthweights that could be used in the clinical setting. Risk factors that overlap as significant predictors of both types of low birthweight include race, no previous live births, smoking, weight under 100 lb, and previous preterm or low birthweight birth. Age also is a significant predictor of both types of low birthweight, but in opposite directions. Younger age is associated with reduced risk of term low birthweight and increased risk of pattern low birthweight. Comparison of all risk factors indicates that different multivariate models are needed to understand the epidemiology of preterm and term low birthweights. In terms of clinical value, a general risk assessment model that combines all low birthweight births is as effective as the separate models.

Maternal and neonatal epidemiological features in clinical subtypes of preterm-birth

PubMed Central

Gimenez, Lucas G.; Krupitzki, Hugo B.; Momany, Allison M.; Gili, Juan A.; Poletta, Fernando A.; Campaña, Hebe; Cosentino, Viviana R.; Saleme, César; Pawluk, Mariela; Murray, Jeffrey C.; Castilla, Eduardo E.; Gadow, Enrique C.; Lopez-Camelo, Jorge S.

2016-01-01

Objective This study was designed to characterize and compare the maternal and newborn epidemiological characteristics through analysis of environmental factors, socio-demographic characteristics, and clinical characteristics between the different clinical subtypes of preterm birth (PTB): Idiopathic (PTB-I), premature rupture of the membranes (PTB-PPROM) and medically indicated (PTB-M). The two subtypes PTB-I and PTB-PPROM grouped are called spontaneous preterm births (PTB-S). Methods A retrospective, observational study was conducted in 1.291 preterm non-malformed singleton live-born children to nulliparous and multiparous mother’s in Tucumán-Argentina between 2005 and 2010. Over 50 maternal variables and ten newborn variables were compared between the different clinical subtypes. The comparisons were done to identify heterogeneity between subtypes of preterm birth: (PTB-S) vs. (PTB-M), and within spontaneous subtype: (PTB-I) vs. (PTB-PPROM). In the same way, two conditional logistic multivariate regressions were used to compare the odds ratio (OR) between PTB-S and PTB-M, as well as PTB-I and PTB-PPROM. We matched for maternal age when comparing maternal variables and gestational age when comparing infant variables. Results The PTB-I subtype was characterized by younger mothers of lower socioeconomic status, PTB-PPROM was characterized by environmental factors resulting from inflammatory processes, and PTB-M was characterized by increased maternal or fetal risk pregnancies. Conclusions The main risk factor for PTB-I and PTB-M was having had a prior preterm delivery, however previous spontaneous abortion was not a risk factor, suggesting a reproductive selection mechanism. PMID:26701680

Independent effects of prematurity on metabolic and cardiovascular risk factors in short small-for-gestational-age children.

PubMed

Willemsen, Ruben H; de Kort, Sandra W K; van der Kaay, Danielle C M; Hokken-Koelega, Anita C S

2008-02-01

Both small-for-gestational-age (SGA) and preterm birth have been associated with an increased incidence of adult cardiovascular disease and diabetes mellitus type 2. However, it is unclear whether preterm birth has an additional effect on cardiovascular risk factors in short children born SGA. Our objective was to investigate whether prematurity has an independent influence on several cardiovascular risk factors within a population of short SGA children. A cross-sectional observational study was performed. A total of 479 short SGA children (mean age 6.8 yr), divided into preterm (<36 wk) and term (> or =36 wk) children, was included in the study. Insulin sensitivity, beta-cell function, body composition, and lipid levels were studied in subgroups, and blood pressure (BP), anthropometry at birth and during childhood in the total group. Preterm SGA children were significantly lighter and shorter at birth after correction for gestational age than term SGA children (P < 0.001) but had a comparable head circumference. In preterm SGA children, we found a significantly higher systolic (P = 0.003) and diastolic BP sd score (P = 0.026), lower percent body fat sd score (P = 0.011), and higher insulin secretion (P = 0.033) and disposition index (P = 0.021), independently of the degree of SGA. Insulin sensitivity, serum lipid levels, muscle mass, and body fat distribution were comparable for preterm and term SGA children. Within a population of short SGA children, preterm birth has divergent effects on several cardiovascular risk factors. Whereas preterm SGA children had a higher systolic and diastolic BP, they also had a lower percent body fat and a higher insulin secretion and disposition index than term SGA children.

Preterm birth and maternal responsiveness during childhood are associated with brain morphology in adolescence.

PubMed

Frye, Richard E; Malmberg, Benjamin; Swank, Paul; Smith, Karen; Landry, Susan

2010-09-01

Although supportive parenting has been shown to have positive effects on development, the neurobiological basis of supportive parenting has not been investigated. Thirty-three adolescents were systemically selected from a longitudinal study on child development based on maternal responsiveness during childhood, a measure of supportive parenting, and whether they were born term or preterm. We analyzed the effect of preterm birth on hemispheric and regional (frontal, temporal, parietal) cortical thickness and surface area using mixed-model analysis while also considering the effect of brain hemisphere (left vs. right). We then determined whether these factors were moderated by maternal responsiveness during childhood. Preterm birth was associated with regional and hemispheric differences in cortical thickness and surface area. Maternal responsiveness during childhood moderated hemispheric cortical thickness. Adolescence with mothers that were inconsistently responsive during childhood demonstrated greater overall cortical thickness and greater asymmetry in cortical thickness during adolescence as compared to adolescence with mothers who were consistently responsive or unresponsive during childhood. Maternal responsiveness and preterm birth did not interact. These data suggest that changes in brain morphology associated with preterm birth continue into adolescence and support the notion that the style of maternal-child interactions during childhood influence brain development into adolescence.

Role of acoustic radiation force impulse and shear wave velocity in prediction of preterm birth: a prospective study.

PubMed

Agarwal, Arjit; Agarwal, Shubhra; Chandak, Shruti

2018-06-01

Background Preterm birth is one of the important causes of neonatal morbidity where we rely on subjective criteria such as modified Bishop's scoring and contemporary sonographic measurement of cervical length. Acoustic radiation force impulse (ARFI) is a technological advancement in elastography that can be employed in prediction of cervical softening and preterm labor. Purpose To evaluate the role of ARFI technique and shear wave velocity (SWV) estimates as a predictor of preterm birth and its comparison with other clinical and sono-elastographic measures. Material and Methods Thirty-four pregnant women (gestation age = 28-37 weeks age) showing features suggestive of preterm labor were included and evaluated with modified Bishop's score, cervical length by ultrasound (US), ARFI to derive Elastography index (EI), and SWV of the cervix. The patients were later divided into two groups, using the clinical outcome of preterm or term delivery. Results Twenty patients delivered at term (gestational age > 37 weeks) and 14 were preterm. Receiver operating characteristics (ROC) curves showed SWV with highest sensitivity and specificity (93% and 90%, respectively) for the prediction of preterm birth at a cutoff value of 2.83 m/s. EI and modified Bishop's score were comparable to each other, but were less sensitive techniques. Conclusion Elastographic assessment of antenatal cervix is a novel technique of virtual palpation of internal os and can be utilized as an objective criterion for preterm birth prediction.

Interventions for treating bacterial vaginosis in pregnancy.

PubMed

Brocklehurst, P; Hannah, M; McDonald, H

2000-01-01

Bacterial vaginosis has been associated with poor perinatal outcome. Since the infections are amenable to treatment, identification during pregnancy and treatment may reduce the risk of preterm birth and its consequences. The objective of this review was to assess the effects of antibiotic treatment of bacterial vaginosis in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. Randomised trials comparing one antibiotic regimen with placebo or no treatment, or which compare two or more alternative antibiotic regimens in pregnant women with bacterial vaginosis. Trial quality assessments and data extraction were done independently by three reviewers. Study authors were contacted for additional information. Five trials involving 1504 women were included. These trials were of good quality. Antibiotic therapy was highly effective at eradicating infection during pregnancy as judged by 'test-of-cure' following therapy (odds ratio 0.22, 95% confidence interval 0.17 to 0.27). The effect of treating bacterial vaginosis during pregnancy showed a trend to less births before 37 weeks gestation (odds ratio 0.78, 95% confidence interval 0.60 to 1.02). The prevention of preterm birth less than 37 weeks gestation was most marked in the subgroup of women with a previous preterm birth (odds ratio 0.37, 95% confidence interval 0.23 to 0. 60). The current evidence does not support screening and treating all pregnant women for bacterial vaginosis to prevent preterm birth and its consequences. For women with a history of a previous preterm birth there is some suggestion that detection and treatment of bacterial vaginosis early in pregnancy may prevent a proportion of these women having a further preterm birth. It is not known whether this is associated with an improvement in neonatal well-being.

Born Toon Soon: Preterm birth matters

PubMed Central

2013-01-01

Urgent action is needed to address preterm birth given that the first country-level estimates show that globally 15 million babies are born too soon and rates are increasing in most countries with reliable time trend data. As the first in a supplement entitled "Born Too Soon", this paper focuses on the global policy context. Preterm birth is critical for progress on Millennium Development Goal 4 (MDG) for child survival by 2015 and beyond, and gives added value to maternal health (MDG 5) investments also linking to non-communicable diseases. For preterm babies who survive, the additional burden of prematurity-related disability may affect families and health systems. Prematurity is an explicit priority in many high-income settings; however, more attention is needed especially in low- and middle-income countries where the invisibility of preterm birth as well as its myths and misconceptions have slowed action on prevention and care. Recent global attention to preterm birth hit a tipping point in 2012, with the May 2 publication of Born Too Soon: The Global Action Report on Preterm Birth and with the 2nd annual World Prematurity Day on November 17 which mobilised the actions of partners in many countries to address preterm birth and newborn health. Interventions to strengthen preterm birth prevention and care span the continuum of care for reproductive, maternal, newborn and child health. Both prevention of preterm birth and implementation of care of premature babies require more research, as well as more policy attention and programmatic investment. Declaration This article is part of a supplement jointly funded by Save the Children's Saving Newborn Lives programme through a grant from The Bill & Melinda Gates Foundation and March of Dimes Foundation and published in collaboration with the World Health Organization (WHO). The original article was published in PDF format in the WHO Report "Born Too Soon: the global action report on preterm birth (ISBN 978 92 4 150343 30). The article has been reformatted for journal publication and has undergone peer review according to Reproductive Health's standard process for supplements and may feature some variations in content when compared to the original report. This co-publication makes the article available to the community in a full-text format. PMID:24625113

Determinants of preterm birth rates in Canada from 1981 through 1983 and from 1992 through 1994.

PubMed

Joseph, K S; Kramer, M S; Marcoux, S; Ohlsson, A; Wen, S W; Allen, A; Platt, R

1998-11-12

The rates of preterm birth have increased in many countries, including Canada, over the past 20 years. However, the factors underlying the increase are poorly understood. We used data from the Statistics Canada live-birth and stillbirth data bases to determine the effects of changes in the frequency of multiple births, registration of births occurring very early in gestation, patterns of obstetrical intervention, and use of ultrasonographic dating of gestational age on the rates of preterm birth in Canada from 1981 through 1983 and from 1992 through 1994. All births in 9 of the 12 provinces and territories of Canada were included. Logistic-regression analysis and Poisson regression analysis were used to estimate changes between the two three-year periods, after adjustment for the above-mentioned determinants of the likelihood of preterm births. Preterm births increased from 6.3 percent of live births in 1981 through 1983 to 6.8 percent in 1992 through 1994, a relative increase of 9 percent (95 percent confidence interval, 7 to 10 percent). Among singleton births, preterm births increased by 5 percent (95 percent confidence interval, 3 to 6 percent). Multiple births increased from 1.9 percent to 2.1 percent of all live births; the rates of preterm birth among live births resulting from multiple gestations increased by 25 percent (95 percent confidence interval, 21 to 28 percent). Adjustment for the determinants of the likelihood of preterm birth reduced the increase in the rate of preterm birth to 3 percent among all live births and 1 percent among singleton births. The recent increase in preterm births in Canada is largely attributable to changes in the frequency of multiple births, obstetrical intervention, and the use of ultrasound-based estimates of gestational age.

Sociodemographic characteristics of mother’s population and risk of preterm birth in Chile

PubMed Central

2013-01-01

Background Preterm birth is a global problem in Perinatal and infant Health. Currently is gaining a growing attention. Rates of preterm birth have increased in most countries, producing a dramatic impact on public health. Factors of diverse nature have been associated to these trends. In Chile, preterm birth has increased since 90. Simultaneously, the advanced demographic transition has modified the characteristics of woman population related to maternity. The principal objective of this study is to analyze some sociodemographic characteristics of the maternal population over time, and their possible association to rates of preterm birth. The second aim is to identify groups of mothers at high risk of having a preterm child. Methods This population-based study examined all liveborn singletons in Chile from 1991 to 2008; divided in three periods. Preterm birth rates were measured as % births <37 weeks of gestation. Logistic regression assessed the risk of preterm birth associated with mother’s age, parity, and marital status, expressed as crude and adjusted odds ratios. Results Over time, rates of preterm birth increased in overall population, especially during the third period (2001–2008). In the same time, characteristics of maternal population changed: significant increase of extreme reproductive ages, significant decrease in parity and increase in mothers living without a partner. Risk of preterm birth remained higher in groups of mothers: <18 and >38 years of age; without a partner; primiparas and grandmultiparas. However, global increase in preterm birth was not explained by the modification of socio demographics characteristics of maternal population. Conclusions Some socio demographic characteristics remained associated with preterm birth over time. These associations allowed identifying five groups of mothers at higher risk to have a preterm child in the population. Increase in overall preterm birth affected all women, even those considered at “low sociodemographic risk” and the contribution of more recent period (2001–2008) to this increase is greater. Then, studied factors couldn’t explain the increase in preterm birth. Further research will have to consider other factors affecting maternal population that could explain the observed trend of preterm birth. PMID:23680406

Does time since immigration modify neighborhood deprivation gradients in preterm birth? A multilevel analysis.

PubMed

Urquia, Marcelo Luis; Frank, John William; Moineddin, Rahim; Glazier, Richard Henry

2011-10-01

Immigrants' health is jointly influenced by their pre- and post-migration exposures, but how these two influences operate with increasing duration of residence has not been well-researched. We aimed to examine how the influence of maternal country of birth and neighborhood deprivation effects, if any, change over time since migration and how neighborhood effects among immigrants compare with those observed in the Canadian-born population. Birth data from Ontario hospital records (2002-2007) were linked with an official Canadian immigration database (1985-2000). The outcome measure was preterm birth. Neighborhoods were ranked according to a neighborhood deprivation index developed for Canadian urban areas and collapsed into tertiles of approximately equal size. Time since immigration was measured from the date of arrival to Canada to the date of delivery, ranging from 1 to 22 years. We used cross-classified random effect models to simultaneously account for the membership of births (N = 83,233) to urban neighborhoods (N = 1,801) and maternal countries of birth (N = 168). There were no differences in preterm birth between neighborhood deprivation tertiles among immigrants with less than 15 years of residence. Among immigrants with 15 years of stay or more, the adjusted absolute risk difference (ARD%, 95% confidence interval) between high-deprived (tertile 3) and low-deprived (tertile 1) neighborhoods was 1.86 (0.68, 2.98), while the ARD% observed among the Canadian-born (N = 314,237) was 1.34 (1.11, 1.57). Time since migration modifies the neighborhood deprivation gradient in preterm birth among immigrants living in Ontario cities. Immigrants reached the level of inequalities in preterm birth observed at the neighborhood level among the Canadian-born after 14 years of stay, but neighborhoods did not influence preterm birth among more recent immigrants, for whom the maternal country of birth was more predictive of preterm birth.

Placental hormone profiles as predictors of preterm birth in twin pregnancy: A prospective cohort study

PubMed Central

Lim, Hui; Powell, Sioned; Mcnamara, Helen C.; Howie, A. Forbes; Doust, Ann; Bowman, Maria E.; Smith, Roger; Norman, Jane E.

2017-01-01

Objective The objective of the study was to analyse placental hormone profiles in twin pregnancies to determine if they could be used to predict preterm birth. Study design Progesterone, estradiol, estriol and corticotropin-releasing hormone were measured using competitive immunoassay and radioimmunoassay in serum and saliva samples of 98 women with twin pregnancies,at 3 or more gestational timepoints. Hormone profiles throughout gestation were compared between very preterm (<34 weeks; n = 8), preterm (<37 weeks; n = 40) and term (37+ weeks; n = 50) deliveries. Results No significant differences were found between preterm and term deliveries in either absolute hormone concentrations or ratios. Estimated hormone concentrations and ratios at 26 weeks did not appear to predict preterm delivery. Salivary and serum hormone concentrations were generally poorly correlated. Conclusion Our results suggest that serial progesterone, estradiol, estriol and corticotropin-releasing hormone measurements in saliva and serum are not robust biomarkers for preterm birth in twin pregnancies. PMID:28278220

Greater brain response to emotional expressions of their own children in mothers of preterm infants: an fMRI study.

PubMed

Montirosso, R; Arrigoni, F; Casini, E; Nordio, A; De Carli, P; Di Salle, F; Moriconi, S; Re, M; Reni, G; Borgatti, R

2017-06-01

The birth of a preterm infant and Neonatal Intensive Care Unit hospitalization constitute a potentially traumatic experience for mothers. Although behavioral studies investigated the parenting stress in preterm mothers, no study focused on the underlying neural mechanisms. We examined the effect of preterm births in mothers, by comparing brain activation in mothers of preterm and full-term infants. We used functional magnetic resonance imaging to measure the cerebral response of 10 first-time mothers of preterm infants (gestational age <32 weeks and/or birth weight <1500) and 11 mothers of full-term infants, viewing happy-, neutral- and distress-face images of their own infant, along with a matched unknown infant. While viewing own infant's face preterm mothers showed increased activation in emotional processing area (i.e., inferior frontal gyrus) and social cognition (i.e., supramarginal gyrus) and affiliative behavior (i.e., insula). Differential brain activation patterns in mothers appears to be a function of the atypical parenthood transition related to prematurity.

The worldwide incidence of preterm birth: a systematic review of maternal mortality and morbidity.

PubMed

Beck, Stacy; Wojdyla, Daniel; Say, Lale; Betran, Ana Pilar; Merialdi, Mario; Requejo, Jennifer Harris; Rubens, Craig; Menon, Ramkumar; Van Look, Paul F A

2010-01-01

To analyse preterm birth rates worldwide to assess the incidence of this public health problem, map the regional distribution of preterm births and gain insight into existing assessment strategies. Data on preterm birth rates worldwide were extracted during a previous systematic review of published and unpublished data on maternal mortality and morbidity reported between 1997 and 2002. Those data were supplemented through a complementary search covering the period 2003-2007. Region-specific multiple regression models were used to estimate the preterm birth rates for countries with no data. We estimated that in 2005, 12.9 million births, or 9.6% of all births worldwide, were preterm. Approximately 11 million (85%) of these preterm births were concentrated in Africa and Asia, while about 0.5 million occurred in each of Europe and North America (excluding Mexico) and 0.9 million in Latin America and the Caribbean. The highest rates of preterm birth were in Africa and North America (11.9% and 10.6% of all births, respectively), and the lowest were in Europe (6.2%). Preterm birth is an important perinatal health problem across the globe. Developing countries, especially those in Africa and southern Asia, incur the highest burden in terms of absolute numbers, although a high rate is also observed in North America. A better understanding of the causes of preterm birth and improved estimates of the incidence of preterm birth at the country level are needed to improve access to effective obstetric and neonatal care.

Predicting preeclampsia from a history of preterm birth

PubMed Central

Ebbing, Cathrine; Irgens, Lorentz M.

2017-01-01

Objective To assess whether women with a history of preterm birth, independent on the presence of prelabour rupture of the membranes (PROM) and growth deviation of the newborn, are more likely to develop preeclampsia with preterm or preterm birth in a subsequent pregnancy. Methods We conducted a population-based cohort study, based on Medical Birth Registry of Norway between 1967 and 2012, including 742,980 women with singleton pregnancies who were followed up from their 1st to 2nd pregnancy. In the analyses we included 712,511 women after excluding 30,469 women with preeclampsia in the first pregnancy. Results After preterm birth without preeclampsia in the first pregnancy, the risk of preterm preeclampsia in the second pregnancy was 4–7 fold higher than after term birth (odds ratios 3.5; 95% confidence interval (CI) 3.0–4.0 to 6.5; 95% CI 5.1–8.2). The risk of term preeclampsia in the pregnancy following a preterm birth was 2–3 times higher than after term birth (odds ratios 1.6; 95% CI 1.5–1.8 to 2.6; 95% CI 2.0–3.4). After spontaneous non-PROM preterm birth and preterm PROM, the risk of preterm preeclampsia was 3.3–3.6 fold higher than after spontaneous term birth. Corresponding risks of term preeclampsia was 1.6–1.8 fold higher. No significant time trends were found in the effect of spontaneous preterm birth in the first pregnancy on preterm or term preeclampsia in the second pregnancy. Conclusions The results suggest that preterm birth, regardless of the presence of PROM, and preeclampsia share pathophysiologic mechanisms. These mechanisms may cause preterm birth in one pregnancy and preeclampsia in a subsequent pregnancy in the same woman. The association was particularly evident with preterm preeclampsia. PMID:28738075

Maternal air pollution exposure and preterm birth in Wuxi, China: Effect modification by maternal age.

PubMed

Han, Yingying; Jiang, Panhua; Dong, Tianyu; Ding, Xinliang; Chen, Ting; Villanger, Gro Dehli; Aase, Heidi; Huang, Lu; Xia, Yankai

2018-08-15

Numerous studies have investigated prenatal air pollution and shown that air pollutants have adverse effect on birth outcomes. However, which trimester was the most sensitive and whether the effect was related to maternal age is still ambiguous. This study aims to explore the association between maternal air pollution exposure during pregnancy and preterm birth, and if this relationship is modified by maternal age. In this retrospective cohort study, we examine the causal relationship of prenatal exposure to air pollutants including particulate matters, which are less than 10 µm (PM 10 ), and ozone (O 3 ), which is one of the gaseous pollutants, on preterm birth by gestational age. A total of 6693 pregnant women were recruited from Wuxi Maternal and Child Health Care Hospital. The participants were dichotomized into child-bearing age group (< 35 years old) and advanced age group (> = 35 years old) in order to analyze the effect modification by maternal age. Logistic and linear regression models were performed to assess the risk for preterm birth (gestational age < 37 weeks) caused by prenatal air pollution exposure. With adjustment for covariates, the highest level of PM 10 exposure significantly increased the risk of preterm birth by 1.42-fold (95% CI: 1.10, 1.85) compared those with the lowest level in the second trimester. Trimester-specific PM 10 exposure was positively associated with gestational age, whereas O 3 exposure was associated with gestational age in the early pregnancy. When stratified by maternal age, PM 10 exposure was significantly associated with an increased risk of preterm birth only in the advanced age group during pregnancy (OR:2.15, 95% CI: 1.13, 4.07). The results suggested that PM 10 exposure associated with preterm birth was modified by advanced maternal age (OR interaction = 2.00, 95% CI: 1.02, 3.91, P interaction = 0.032). Prenatal air pollution exposure would increase risk of preterm birth and reduced gestational age. Thus, more attention should be paid to the effects of ambient air pollution exposure on preterm birth especially in pregnant women with advanced maternal age. Copyright © 2018 Elsevier Inc. All rights reserved.

Combinatory approaches prevent preterm birth profoundly exacerbated by gene-environment interactions

PubMed Central

Cha, Jeeyeon; Bartos, Amanda; Egashira, Mahiro; Haraguchi, Hirofumi; Saito-Fujita, Tomoko; Leishman, Emma; Bradshaw, Heather; Dey, Sudhansu K.; Hirota, Yasushi

2013-01-01

There are currently more than 15 million preterm births each year. We propose that gene-environment interaction is a major contributor to preterm birth. To address this experimentally, we generated a mouse model with uterine deletion of Trp53, which exhibits approximately 50% incidence of spontaneous preterm birth due to premature decidual senescence with increased mTORC1 activity and COX2 signaling. Here we provide evidence that this predisposition provoked preterm birth in 100% of females exposed to a mild inflammatory insult with LPS, revealing the high significance of gene-environment interactions in preterm birth. More intriguingly, preterm birth was rescued in LPS-treated Trp53-deficient mice when they were treated with a combination of rapamycin (mTORC1 inhibitor) and progesterone (P4), without adverse effects on maternal or fetal health. These results provide evidence for the cooperative contributions of two sites of action (decidua and ovary) toward preterm birth. Moreover, a similar signature of decidual senescence with increased mTORC1 and COX2 signaling was observed in women undergoing preterm birth. Collectively, our findings show that superimposition of inflammation on genetic predisposition results in high incidence of preterm birth and suggest that combined treatment with low doses of rapamycin and P4 may help reduce the incidence of preterm birth in high-risk women. PMID:23979163

Seasonal Pattern of Preterm Births in Korea for 2000-2012.

PubMed

Woo, Yoonmi; Ouh, Yung Taek; Ahn, Ki Hoon; Cho, Geum Joon; Hong, Soon Cheol; Oh, Min Jeong; Kim, Hai Joong

2016-11-01

The aim of this study was to investigate a seasonal pattern of preterm births in Korea. Data were obtained from the national birth registry of the Korean Statistics Office and included all births in Korea during the period 2000-2012 (n = 6,310,800). Delivery dates were grouped by month of the year or by season (winter [December, January, February], spring [March, April, May], summer [June, July, August], and autumn [September, October, November]). The seasonal patterns of prevalence of preterm births were assessed. The rates of preterm births at 37 weeks were highest twice a year (once in winter and again in summer). The rates of preterm births increased by 13.9% in summer and 7.5% in winter, respectively, than in spring (OR, 1.139; 95% CI, 1.127-1.152, and OR, 1.075; 95% 1.064-1.087, respectively) after controlling for age, the educational level of the parents, maternal parity, and neonatal gender. The pattern for spontaneous preterm births < 34 weeks was similar. In Korea, a seasonal pattern of preterm births was observed, with peak prevalence in summer and winter. A seasonal pattern of preterm births may provide new insights for the pathophysiology of preterm births.

Arousal from sleep pathways are affected by the prone sleeping position and preterm birth: preterm birth, prone sleeping and arousal from sleep.

PubMed

Richardson, Heidi L; Horne, Rosemary S C

2013-09-01

Preterm infants exhibit depressed arousability from sleep when compared with term infants. As the final cortical element of the arousal process may be the most critical for survival, we hypothesized that the increased vulnerability of preterm infants to the Sudden Infant Death Syndrome (SIDS) could be explained by depressed cortical arousal (CA) responses. We evaluated the effects of preterm birth on stimulus-induced arousal processes in both the prone and supine sleeping positions. 10 healthy preterm infants were studied with daytime polysomnography, in both supine and prone sleeping positions, at 36 weeks gestational age, 2-4 weeks, 2-3 months and 5-6 months post-term corrected age. Sub-cortical activations and cortical arousals (CA) were expressed as proportions of total arousal responses. Preterm data were compared with data from 13 healthy term infants studied at the same corrected ages. In preterm infants increased CAs were observed in the prone position at all ages studied. Compared to term infants, preterm infants had significantly fewer CAs in QS when prone at 2-3 months of age and more CAs when prone at 2-4 weeks in AS. There were no differences in either sleep state when infants slept supine. Prone sleeping promoted CA responses in healthy preterm infants throughout the first six months of post-term age. We have previously suggested that in term infants enhanced CA represents a critical protection against a potentially harmful situation; we speculate that for preterm-born infants the need for this protection is greater than in term infants. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

Prenatal stress alters amygdala functional connectivity in preterm neonates.

PubMed

Scheinost, Dustin; Kwon, Soo Hyun; Lacadie, Cheryl; Sze, Gordon; Sinha, Rajita; Constable, R Todd; Ment, Laura R

2016-01-01

Exposure to prenatal and early-life stress results in alterations in neural connectivity and an increased risk for neuropsychiatric disorders. In particular, alterations in amygdala connectivity have emerged as a common effect across several recent studies. However, the impact of prenatal stress exposure on the functional organization of the amygdala has yet to be explored in the prematurely-born, a population at high risk for neuropsychiatric disorders. We test the hypothesis that preterm birth and prenatal exposure to maternal stress alter functional connectivity of the amygdala using two independent cohorts. The first cohort is used to establish the effects of preterm birth and consists of 12 very preterm neonates and 25 term controls, all without prenatal stress exposure. The second is analyzed to establish the effects of prenatal stress exposure and consists of 16 extremely preterm neonates with prenatal stress exposure and 10 extremely preterm neonates with no known prenatal stress exposure. Standard resting-state functional magnetic resonance imaging and seed connectivity methods are used. When compared to term controls, very preterm neonates show significantly reduced connectivity between the amygdala and the thalamus, the hypothalamus, the brainstem, and the insula (p < 0.05). Similarly, when compared to extremely preterm neonates without exposure to prenatal stress, extremely preterm neonates with exposure to prenatal stress show significantly less connectivity between the left amygdala and the thalamus, the hypothalamus, and the peristriate cortex (p < 0.05). Exploratory analysis of the combined cohorts suggests additive effects of prenatal stress on alterations in amygdala connectivity associated with preterm birth. Functional connectivity from the amygdala to other subcortical regions is decreased in preterm neonates compared to term controls. In addition, these data, for the first time, suggest that prenatal stress exposure amplifies these decreases.

An Evolutionary Genomic Approach to Identify Genes Involved in Human Birth Timing

PubMed Central

Orabona, Guilherme; Morgan, Thomas; Haataja, Ritva; Hallman, Mikko; Puttonen, Hilkka; Menon, Ramkumar; Kuczynski, Edward; Norwitz, Errol; Snegovskikh, Victoria; Palotie, Aarno; Fellman, Vineta; DeFranco, Emily A.; Chaudhari, Bimal P.; McGregor, Tracy L.; McElroy, Jude J.; Oetjens, Matthew T.; Teramo, Kari; Borecki, Ingrid; Fay, Justin; Muglia, Louis

2011-01-01

Coordination of fetal maturation with birth timing is essential for mammalian reproduction. In humans, preterm birth is a disorder of profound global health significance. The signals initiating parturition in humans have remained elusive, due to divergence in physiological mechanisms between humans and model organisms typically studied. Because of relatively large human head size and narrow birth canal cross-sectional area compared to other primates, we hypothesized that genes involved in parturition would display accelerated evolution along the human and/or higher primate phylogenetic lineages to decrease the length of gestation and promote delivery of a smaller fetus that transits the birth canal more readily. Further, we tested whether current variation in such accelerated genes contributes to preterm birth risk. Evidence from allometric scaling of gestational age suggests human gestation has been shortened relative to other primates. Consistent with our hypothesis, many genes involved in reproduction show human acceleration in their coding or adjacent noncoding regions. We screened >8,400 SNPs in 150 human accelerated genes in 165 Finnish preterm and 163 control mothers for association with preterm birth. In this cohort, the most significant association was in FSHR, and 8 of the 10 most significant SNPs were in this gene. Further evidence for association of a linkage disequilibrium block of SNPs in FSHR, rs11686474, rs11680730, rs12473870, and rs1247381 was found in African Americans. By considering human acceleration, we identified a novel gene that may be associated with preterm birth, FSHR. We anticipate other human accelerated genes will similarly be associated with preterm birth risk and elucidate essential pathways for human parturition. PMID:21533219

Preterm Birth: An Overview of Risk Factors and Obstetrical Management

ERIC Educational Resources Information Center

Stewart, Amanda; Graham, Ernest

2010-01-01

Preterm birth is the leading cause of neonatal mortality and a major public health concern. Risk factors for preterm birth include a history of preterm birth, short cervix, infection, short interpregnancy interval, smoking, and African-American race. The use of progesterone therapy to treat mothers at risk for preterm delivery is becoming more…

Perinatal Risks in “Late Motherhood” Defined Based On Parity and Preterm Birth Rate – an Analysis of the German Perinatal Survey (20th Communication)

PubMed Central

Schure, V.; Voigt, M.; Schild, R. L.; Hesse, V.; Carstensen, M.; Schneider, K. T. M.; Straube, S.

2012-01-01

Aim: “Late motherhood” is associated with greater perinatal risks but the term lacks precise definition. We present an approach to determine what “late motherhood” associated with “high risk” is, based on parity and preterm birth rate. Materials and Methods: Using data from the German Perinatal Survey of 1998–2000 we analysed preterm birth rates in women with zero, one, or two previous live births. We compared groups of “late” mothers (with high preterm birth rates) with “control” groups of younger women (with relatively low preterm birth rates). Data of 208 342 women were analysed. For women with zero (one; two) previous live births, the “control” group included women aged 22–26 (27–31; 29–33) years. Women in the “late motherhood” group were aged > 33 (> 35; > 38) years. Results: The “late motherhood” groups defined in this way were also at higher risk of adverse perinatal events other than preterm birth. For women with zero (one; two) previous live births, normal cephalic presentation occurred in 89 % (92.7 %; 93.3 %) in the “control” group, but only in 84.5 % (90 %; 90.4 %) in the “late motherhood” group. The mode of delivery was spontaneous or at most requiring manual help in 71.3 % (83.4 %; 85.8 %) in the “control” group, but only in 51.4 % (72.2 %; 76.4 %) in the “late motherhood” group. Five-minute APGAR scores were likewise worse for neonates of “late” mothers and the proportion with a birth weight ≤ 2499 g was greater. Conclusion: “Late motherhood” that is associated with greater perinatal risks can be defined based on parity and preterm birth rate. PMID:25253904

Transvaginal ultrasonographic measurement of cervical length in asymptomatic high-risk women with a short cervical length in the previous pregnancy.

PubMed

Crane, J M G; Hutchens, D

2011-07-01

To determine if asymptomatic women at high risk of preterm delivery who had a short cervical length in their previous pregnancy and delivered at term are at increased risk of having a short cervical length in their next pregnancy, and whether they are at increased risk of preterm birth. This retrospective cohort study included high-risk (those with a history of spontaneous preterm birth, uterine anomaly or excisional treatment for cervical dysplasia) asymptomatic women who were pregnant with a singleton gestation delivering between April 2003 and March 2010, who had had a previous pregnancy and who had transvaginal ultrasonographic cervical length measurement performed at 16-30 weeks' gestation in both pregnancies. Comparison was among women who had a short cervical length (< 3.0 cm) in their previous pregnancy but delivered at term in that pregnancy (Short Term Group), women with a history of a normal cervical length (≥ 3.0 cm) in their previous pregnancy delivering at term (Long Term Group), and women who had a short cervical length (< 3.0 cm) in their previous pregnancy delivering preterm (Short Preterm Group). Primary outcomes were spontaneous preterm birth at < 37 weeks' gestation and cervical length. Secondary outcomes were spontaneous preterm birth at < 35 weeks and < 32 weeks, low birth weight, maternal outcomes and neonatal morbidity. A total of 62 women were included. Women in the Short Term Group were more likely to have a short cervical length in their next pregnancy compared with those in the Long Term Group (10/23 (43.5%) vs. 4/26 (15.4%), respectively) but not as likely as women in the Short Preterm Group (9/13 (69.2%); P=0.003). Women in the Short Term Group were not at an increased risk of spontaneous preterm birth at < 37 weeks in the next pregnancy compared with women in the Long Term Group (2/23 (8.7%) vs. 2/26 (7.7%), respectively), but women in the Short Preterm Group were at an increased risk (6/13 (46.2%); P<0.0001). Compared with women in the Short Term and Long Term groups, women in the Short Preterm Group were also at an increased risk of threatened preterm labor (6/23 (26.1%) and 4/26 (15.4%) vs. 9/13 (69.2%), respectively; P=0.002) and of receiving corticosteroids for fetal lung maturation (6/23 (26.1%) and 4/26 (15.4%) vs. 11/13 (84.6%), respectively; P<0.0001). Although high-risk asymptomatic women with a short cervical length in their previous pregnancy who delivered at term are at increased risk of having a short cervix in their next pregnancy, they are not at increased risk of preterm birth. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

Nonresponse to 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention: clinical prediction and generation of a risk scoring system.

PubMed

Manuck, Tracy A; Stoddard, Gregory J; Fry, Rebecca C; Esplin, M Sean; Varner, Michael W

2016-11-01

Spontaneous preterm birth remains a leading cause of neonatal morbidity and mortality among nonanomalous neonates in the United States. Spontaneous preterm birth tends to recur at similar gestational ages. Intramuscular 17-alpha hydroxyprogesterone caproate reduces the risk of recurrent spontaneous preterm birth. Unfortunately, one-third of high-risk women will have a recurrent spontaneous preterm birth despite 17-alpha hydroxyprogesterone caproate therapy; the reasons for this variability in response are unknown. We hypothesized that clinical factors among women treated with 17-alpha hydroxyprogesterone caproate who suffer recurrent spontaneous preterm birth at a similar gestational age differ from women who deliver later, and that these associations could be used to generate a clinical scoring system to predict 17-alpha hydroxyprogesterone caproate response. Secondary analysis of a prospective, multicenter, randomized controlled trial enrolling women with ≥1 previous singleton spontaneous preterm birth <37 weeks' gestation. Participants received daily omega-3 supplementation or placebo for the prevention of recurrent preterm birth; all were provided 17-alpha hydroxyprogesterone caproate. Women were classified as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest previous spontaneous preterm birth. Responders were women with pregnancy extending ≥3 weeks later compared with the delivery gestational age of their earliest previous preterm birth; nonresponders delivered earlier or within 3 weeks of the gestational age of their earliest previous preterm birth. A risk score for nonresponse to 17-alpha hydroxyprogesterone caproate was generated from regression models via the use of clinical predictors and was validated in an independent population. Data were analyzed with multivariable logistic regression. A total of 754 women met inclusion criteria; 159 (21%) were nonresponders. Responders delivered later on average (37.7±2.5 weeks) than nonresponders (31.5±5.3 weeks), P<.001. Among responders, 27% had a recurrent spontaneous preterm birth (vs 100% of nonresponders). Demographic characteristics were similar between responders and nonresponders. In a multivariable logistic regression model, independent risk factors for nonresponse to 17-alpha hydroxyprogesterone caproate were each additional week of gestation of the earliest previous preterm birth (odds ratio, 1.23; 95% confidence interval, 1.17-1.30, P<.001), placental abruption or significant vaginal bleeding (odds ratio, 5.60; 95% confidence interval, 2.46-12.71, P<.001), gonorrhea and/or chlamydia in the current pregnancy (odds ratio, 3.59; 95% confidence interval, 1.36-9.48, P=.010), carriage of a male fetus (odds ratio, 1.51; 95% confidence interval, 1.02-2.24, P=.040), and a penultimate preterm birth (odds ratio, 2.10; 95% confidence interval, 1.03-4.25, P=.041). These clinical factors were used to generate a risk score for nonresponse to 17-alpha hydroxyprogesterone caproate as follows: black +1, male fetus +1, penultimate preterm birth +2, gonorrhea/chlamydia +4, placental abruption +5, earliest previous preterm birth was 32-36 weeks +5. A total risk score >6 was 78% sensitive and 60% specific for predicting nonresponse to 17-alpha hydroxyprogesterone caproate (area under the curve=0.69). This scoring system was validated in an independent population of 287 women; in the validation set, a total risk score >6 performed similarly with a 65% sensitivity, 67% specificity and area under the curve of 0.66. Several clinical characteristics define women at risk for recurrent preterm birth at a similar gestational age despite 17-alpha hydroxyprogesterone caproate therapy and can be used to generate a clinical risk predictor score. These data should be refined and confirmed in other cohorts, and women at high risk for nonresponse should be targets for novel therapeutic intervention studies. Copyright © 2016 Elsevier Inc. All rights reserved.

[Effect of positive nutritional support strategy on extrauterine growth restriction in preterm infants].

PubMed

Wang, Xue-Min; Zhu, Yan-Ping; Wang, Li

2013-12-01

To investigate the effects of positive nutritional support in the early stage after birth on the nutritional status during hospitalization and extrauterine growth restriction (EUGR) in preterm infants. There were two groups of preterm infants. Group A (n=99) was given the previous nutritional program, while group B (n=101) was given positive nutritional support. The nutritional intake, growth rate and EUGR incidence were compared between the two groups. Compared with group A, group B had significantly higher enteral calorie intake and total calorie intake within one week after birth. Additionally, the age of first feeding, time of regaining birth weight, duration of intravenous nutrition, time to full enteral feeding, and length of hospital stay in group B were all shorter than in group A. Group B also had less physiological weight loss than group A. Among the preterm infants with a gestational age less than 32 weeks, group B had faster increases in body weight, head circumference, and body length and a lower incidence of EUGR compared with group A. Among the preterm infants with a gestational age not less than 32 weeks, group B had faster increases in body weight and a lower incidence of EUGR (evaluated based on body weight and head circumference) compared with group A. During hospitalization, group B had significantly lower incidence of feeding intolerance, necrotizing enterocolitis, and sepsis than group A. Positive nutritional support strategy, applied in preterm infants early after birth, can effectively improve their nutritional status during hospitalization and reduce the incidence of EUGR without increasing the incidence of related complications during hospitalization.

Reduced brachial flow-mediated vasodilation in young adult ex extremely low birth weight preterm: a condition predictive of increased cardiovascular risk?

PubMed

Bassareo, P P; Fanos, V; Puddu, M; Demuru, P; Cadeddu, F; Balzarini, M; Mercuro, G

2010-10-01

Sporadic data present in literature report how preterm birth and low birth weight constitute the risk factors for the development of cardiovascular diseases in later life. To assess the presence of potential alterations to endothelial function in young adults born preterm at extremely low birth weight (<1000 g; ex ELBW). Thirty-two ex-ELBW subjects (10 males [M] and 22 females [F], aged 17-28 years, mean [+/- DS] 20.1 +/- 2.5 years) were compared with 32 healthy, age-matched subjects born at term (C, 9 M and 23 F). 1) pathological conditions known to affect endothelial function; 2) administration of drugs known to affect endothelial function. Endothelial function was assessed by non-invasive finger plethysmography, previously validated by the US Food and Drug Administration (Endopath; Itamar Medical Ltd., Cesarea, Israel). Endothelial function was significantly reduced in ex-ELBW subjects compared to C (1.94 +/- 0.37 vs. 2.68 +/- 0.41, p < 0.0001). Moreover, this function correlated significantly with gestational age (r = 0.56, p < 0.0009) and birth weight (r = 0.63, p < 0.0001). The results obtained reveal a significant decrease in endothelial function of ex-ELBW subjects compared to controls, underlining a probable correlation with preterm birth and low birth weight. Taken together, these results suggest that an ELBW may underlie the onset of early circulatory dysfunction predictive of increased cardiovascular risk.

Retinol-Binding Protein 4 and Lipids Prospectively Measured During Early to Mid-Pregnancy in Relation to Preeclampsia and Preterm Birth Risk.

PubMed

Mendola, Pauline; Ghassabian, Akhgar; Mills, James L; Zhang, Cuilin; Tsai, Michael Y; Liu, Aiyi; Yeung, Edwina H

2017-06-01

Maternal retinol-binding protein 4 (RBP4) and lipids may relate to preeclampsia and preterm birth risk but longitudinal data are lacking. This study examines these biomarkers longitudinally during pregnancy in relation to preeclampsia and preterm birth risk. Maternal serum samples from the Calcium for Preeclampsia Prevention (CPEP) trial were analyzed at baseline: average 15 gestational weeks; mid-pregnancy: average 27 weeks; and at >34 weeks. We measured RBP4, total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides and lipoprotein (a) (Lp(a)). Cross-sectional logistic regression analyses estimated the odds ratio (OR) and 95% confidence intervals (CI) for preterm preeclampsia (n = 63), term preeclampsia (n = 104), and preterm delivery (n = 160) associated with RBP4 and lipids at baseline and mid-pregnancy compared with controls (n = 136). Longitudinal trajectories across pregnancy were assessed using mixed linear models with fixed effects. Adjusted models included clinical and demographic factors. RBP4 concentrations at baseline and mid-pregnancy were associated with a 4- to 8-fold increase in preterm preeclampsia risk but were not associated with term preeclampsia. RBP4 measured mid-pregnancy was also associated with preterm birth (OR = 6.67, 95% CI: 1.65, 26.84). Higher triglyceride concentrations in mid-pregnancy were associated with a 2- to 4-fold increased risk for both preeclampsia and preterm birth. Longitudinal models demonstrate that both preterm preeclampsia and preterm birth cases had elevated RBP4 throughout gestation. Elevated RBP4 is detectable early in pregnancy and its strong relation with preterm preeclampsia merits further investigation and confirmation to evaluate its potential use as a predictor, particularly among high-risk women. © Published by Oxford University Press on behalf of American Journal of Hypertension Ltd 2017. This work is written by (a) US Government employees(s) and is in the public domain in the US.

Vaginal progesterone to prevent preterm birth in pregnant women with a sonographic short cervix: clinical and public health implications.

PubMed

Conde-Agudelo, Agustin; Romero, Roberto

2016-02-01

Vaginal progesterone administration to women with a sonographic short cervix is an efficacious and safe intervention used to prevent preterm birth and neonatal morbidity and mortality. The clinical and public health implications of this approach in the United States have been critically appraised and compared to other therapeutic interventions in obstetrics. Vaginal progesterone administration to women with a transvaginal sonographic cervical length (CL) ≤25 mm before 25 weeks of gestation is associated with a significant and substantial reduction of the risk for preterm birth from <28 to <35 weeks of gestation, respiratory distress syndrome, composite neonatal morbidity and mortality, admission to the neonatal intensive care unit, and mechanical ventilation. These beneficial effects have been achieved in women with a singleton gestation, with or without a history of spontaneous preterm birth, and did not differ significantly as a function of CL (<10 mm, 10-20 mm, or 21-25 mm). The number of patients required for treatment to prevent 1 case of preterm birth or adverse neonatal outcomes ranges from 10-19 women. The number needed to screen for the prevention of 1 case of preterm birth before 34 weeks of gestation is 125 women, and 225 for the prevention of 1 case of major neonatal morbidity or neonatal mortality. Several cost-effectiveness and decision analyses have shown that the combination of universal transvaginal CL screening and vaginal progesterone administration to women with a short cervix is a cost-effective intervention that prevents preterm birth and associated perinatal morbidity and mortality. Universal assessment of CL and treatment with vaginal progesterone for singleton gestations in the United States would result in an annual reduction of approximately 30,000 preterm births before 34 weeks of gestation and of 17,500 cases of major neonatal morbidity or neonatal mortality. In summary, there is compelling evidence to recommend universal transvaginal CL screening at 18-24 weeks of gestation in women with a singleton gestation and to offer vaginal progesterone to those with a CL ≤25 mm, regardless of the history of spontaneous preterm birth, with the goal of preventing preterm birth and neonatal morbidity and mortality. Published by Elsevier Inc.

A Comparison of Maternal and Paternal Experiences of Becoming Parents of a Very Preterm Infant.

PubMed

Provenzi, Livio; Barello, Serena; Fumagalli, Monica; Graffigna, Guendalina; Sirgiovanni, Ida; Savarese, Mariarosaria; Montirosso, Rosario

2016-01-01

To compare maternal and paternal experiences of very preterm (VPT) birth (gestational age < 32 weeks) and the NICU stay. Qualitative study. Data collection took place at parents' homes 3 to 6 months after NICU discharge. Ten parental couples participated in the study (20 parents). All VPT infants were healthy, without any neonatal or postnatal complications or injuries. Computer-assisted content analysis was used to highlight thematic clusters from parents' narratives, which were labeled through qualitative interpretation. Two main dimensions (Adjustment Process to Preterm Birth and Parental Role Assumption) and three main thematic clusters (Facing the Unexpected, Learning to Parent, and Finally Back Home) described the parental experience. Mothers focused mostly on the Finally Back Home cluster, which was characterized by moderate levels of adjustment to preterm birth and by awareness of their own maternal roles. Fathers focused mostly on the Learning to Parent cluster, which was characterized by low to moderate levels of adjustment to preterm birth and by a limited assumption of paternal role. To our knowledge, this study is unique in that we compared mothers and fathers who experienced the VPT births of their infants and described their experiences of the NICU stay. We found that the VPT birth experience for parents involves a dynamic adjustment. Differences in maternal and paternal experiences may indicate the need for tailored supportive interventions in the NICU. Copyright © 2016 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

Comparison of maternal omentin-1 levels and genetic variability between spontaneous term and preterm births.

PubMed

Šplíchal, Zbyněk; Zlámal, Filip; Máchal, Jan; Lipková, Jolana; Pavlová, Tereza; Hodická, Zuzana; Ventruba, Pavel; Vašků, Anna; Bienertová-Vašků, Julie

2018-07-01

To determine maternal omentin-1 levels and genetic variability in the omentin-1 gene in women with spontaneous term and preterm births (PTBs). Maternal serum omentin-1 levels and the role of the omentin-1 Val109Asp (rs2274907) polymorphism were evaluated in 32 women with spontaneous term birth (sTB) and 30 women with spontaneous preterm birth (sPTB) including women with (n = 16) and without (n = 14) preterm premature rupture of membranes (PPROM). Maternal omentin-1 levels were significantly lower in women with sPTBs compared to term births during the hospitalization period (p = .015). However, maternal omentin-1 levels were similar in women with sPTBs with and without PPROM (p = .990). Furthermore, the omentin-1 Val109Asp polymorphism was found to have no significant effect on omentin-1 serum levels. In addition, no significant differences in genotype distributions and allelic frequencies between sTB and sPTB were established. High omentin-1 levels in normal sTBs compared to PTBs without significant differences between cases with and without PPROM suggest that omentin-1 plays a potential role in the pathophysiology of PTB but not in the PPROM mechanism itself.

Magnesium sulphate for preventing preterm birth in threatened preterm labour.

PubMed

Crowther, Caroline A; Brown, Julie; McKinlay, Christopher J D; Middleton, Philippa

2014-08-15

Magnesium sulphate has been used in some settings as a tocolytic agent to inhibit uterine activity in women in preterm labour with the aim of preventing preterm birth. To assess the effects of magnesium sulphate therapy given to women in threatened preterm labour with the aim of preventing preterm birth and its sequelae. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (last searched 31 January 2014). Randomised controlled trials of magnesium sulphate as the only tocolytic, administered by any route, compared with either placebo, no treatment or alternative tocolytic therapy (not magnesium sulphate) to women considered to be in preterm labour. At least two review authors assessed trial eligibility and risk of bias and undertook data extraction independently. The 37 included trials (total of 3571 women and over 3600 babies) were generally of moderate to high risk of bias. Antenatal magnesium sulphate was compared with either placebo, no treatment, or a range of alternative tocolytic agents.For the primary outcome of giving birth within 48 hours after trial entry, no significant differences were seen between women who received magnesium sulphate and women who did not (whether placebo/no alternative tocolytic drug, betamimetics, calcium channel blockers, cox inhibitors, prostaglandin inhibitors, or human chorionic gonadotropin) (19 trials, 1913 women). Similarly for the primary outcome of serious infant outcome, there were no significant differences between the infants exposed to magnesium sulphate and those not (whether placebo/no alternative tocolytic drug, betamimetics, calcium channel blockers, cox inhibitors, prostaglandin inhibitors, human chorionic gonadotropin or various tocolytic drugs) (18 trials; 2187 babies). No trials reported the outcome of extremely preterm birth. In the seven trials that reported serious maternal outcomes, no events were recorded.In the group treated with magnesium sulphate compared with women receiving antenatal placebo or no alternative tocolytic drug, a borderline increased risk of total death (fetal, neonatal, infant) was seen (risk ratio (RR) 4.56, 95% confidence interval (CI) 1.00 to 20.86; two trials, 257 babies); none of the comparisons between magnesium sulphate and other classes of tocolytic drugs showed differences for this outcome (10 trials, 991 babies). The outcomes of neonatal and/or infant deaths and of fetal deaths did not show differences between magnesium sulphate and no magnesium sulphate, whether compared with placebo/no alternative tocolytic drug, or any specific class of tocolytic drug. For most of the other secondary outcomes, there were no significant differences between magnesium sulphate and the control groups for risk of preterm birth (except for a significantly lower risk with magnesium sulphate when compared with barbiturates in one trial of 65 women), gestational age at birth, interval between trial entry and birth, other neonatal morbidities, or neurodevelopmental outcomes. Duration of neonatal intensive care unit stay was significantly increased in the magnesium sulphate group compared with the calcium channel blocker group, but not when compared with cox inhibitors or prostaglandin inhibitors. No maternal deaths were reported in the four trials reporting this outcome. Significant differences between magnesium sulphate and controls were not seen for maternal adverse events severe enough to stop treatment, except for a significant benefit of magnesium sulphate compared with betamimetics in a single trial. Magnesium sulphate is ineffective at delaying birth or preventing preterm birth, has no apparent advantages for a range of neonatal and maternal outcomes as a tocolytic agent and its use for this indication may be associated with an increased risk of total fetal, neonatal or infant mortality (in contrast to its use in appropriate groups of women for maternal, fetal, neonatal and infant neuroprotection where beneficial effects have been demonstrated).

Factors associated with initiation and exclusive breastfeeding at hospital discharge: late preterm compared to 37 week gestation mother and infant cohort.

PubMed

Ayton, Jennifer; Hansen, Emily; Quinn, Stephen; Nelson, Mark

2012-11-26

To investigate and examine the factors associated with initiation of, and exclusive breastfeeding at hospital discharge of, late preterm (34 0/7 - 36 6/7 weeks) compared to 37 week gestation (37 0/7 - 37 6/7 week) mother and baby pairs. A retrospective population-based cohort study using a Perinatal National Minimum Data Set and clinical medical records review, at the Royal Hobart Hospital, Tasmania, Australia in 2006. Late preterm and 37 week gestation infants had low rates of initiation of breastfeeding within one hour of birth, 31 (21.1%) and 61 (41.5%) respectively. After multiple regression analysis, late preterm infants were less likely to initiate breastfeeding within one hour of birth (OR 0.3 95% CI 0.1, 0.7 p = 0.009) and were less likely to be discharged exclusively breastfeeding from hospital (OR 0.4 95% CI 0.1, 1.0 p = 0.04) compared to 37 week gestation infants. A late preterm birth is predictive of breastfeeding failure, with late preterm infants at greater risk of not initiating breastfeeding and/or exclusively breastfeeding at hospital discharge, compared with those infants born at 37 weeks gestation. Stratifying breastfeeding outcomes by gestational age groups may help to identify those sub-populations at greatest risk of premature cessation of breastfeeding.

Cost effectiveness of a screen-and-treat program for asymptomatic vaginal infections in pregnancy: towards a significant reduction in the costs of prematurity.

PubMed

Kiss, H; Pichler, Eva; Petricevic, L; Husslein, P

2006-08-01

The purpose of this investigation was to determine the cost-saving potential of a simple screen-and-treat program for vaginal infection, which has previously been shown to lead to a reduction of 50% in the rate of preterm births. To determine the potential cost savings, we compared the direct costs of preterm delivery of infants with a birth weight below 1900g with the costs of the screen-and-treat program. We used a cut-off birth weight of 1900g because, in our population, all infants with a birth weight below 1900g were transferred to the neonatal intensive care unit. The direct costs associated with preterm delivery were defined to include the costs of the initial hospitalization of both mother and infant and the costs of outpatient follow-up throughout the first 6 years of life of the former preterm infant. The costs of the screen-and-treat program were defined to include the costs of the screening examination and the resulting costs of antimicrobial treatment and follow-up. All calculations were based on health-economic data obtained in the metropolitan area of Vienna, Austria. The number of preterm infants with a birth weight below 1900g was 12 (0.5%) in the intervention group (N=2058) and 29 (1.3%) in the control group (N=2097). The direct costs per preterm birth were found to amount to EUR (euro) 60262. Overall, the expected total savings in direct costs achieved by the screen-and-treat program and the ensuing 50% reduction in the number preterm births with a birth weight below 1900g amounted to more than euro 11 million. The costs of screening and treatment were found to amount to merely 7% of the direct costs saved as a result of the screen-and-treat program. A simple preterm prevention program, consisting of screening and antimicrobial treatment and follow-up of women with asymptomatic vaginal infection, leads not only to a significant reduction in the rate of preterm births but also to substantial savings in the direct costs associated with prematurity.

Developmental Outcomes of Late Preterm Infants From Infancy to Kindergarten

PubMed Central

Kaciroti, Niko; Richards, Blair; Oh, Wonjung; Lumeng, Julie C.

2016-01-01

OBJECTIVE: To compare developmental outcomes of late preterm infants (34–36 weeks’ gestation) with infants born at early term (37–38 weeks’ gestation) and term (39–41 weeks’ gestation), from infancy through kindergarten. METHODS: Sample included 1000 late preterm, 1800 early term, and 3200 term infants ascertained from the Early Childhood Longitudinal Study, Birth Cohort. Direct assessments of development were performed at 9 and 24 months by using the Bayley Short Form–Research Edition T-scores and at preschool and kindergarten using the Early Childhood Longitudinal Study, Birth Cohort reading and mathematics θ scores. Maternal and infant characteristics were obtained from birth certificate data and parent questionnaires. After controlling for covariates, we compared mean developmental outcomes between late preterm and full-term groups in serial cross-sectional analyses at each timepoint using multilinear regression, with pairwise comparisons testing for group differences by gestational age categories. RESULTS: With covariates controlled at all timepoints, at 9 months late preterm infants demonstrated less optimal developmental outcomes (T = 47.31) compared with infants born early term (T = 49.12) and term (T = 50.09) (P < .0001). This association was not seen at 24 months, (P = .66) but reemerged at preschool. Late preterm infants demonstrated less optimal scores in preschool reading (P = .0006), preschool mathematics (P = .0014), and kindergarten reading (P = .0007) compared with infants born at term gestation. CONCLUSIONS: Although late preterm infants demonstrate comparable developmental outcomes to full-term infants (early term and full-term gestation) at 24 months, they demonstrate less optimal reading outcomes at preschool and kindergarten timepoints. Ongoing developmental surveillance for late preterm infants is warranted into preschool and kindergarten. PMID:27456513

Preterm birth, an unresolved issue.

PubMed

Belizán, Jose M; Hofmeyr, Justus; Buekens, Pierre; Salaria, Natasha

2013-11-15

Premature birth is the world's leading cause of neonatal mortality with worldwide estimates indicating 11.1% of all live births were preterm in 2010. Preterm birth rates are increasing in most countries with continual differences in survival rates amongst rich and poor countries. Preterm birth is currently an important unresolved global issue with research efforts focusing on uterine quiescence and activation, the 'omics' approaches and implementation science in order to reduce the incidence and increase survival rates of preterm babies. The journal Reproductive Health has published a supplement entitled Born Too Soon which addresses factors in the preconception and pregnancy period which may increase the risk of preterm birth and also outlines potential interventions which may reduce preterm birth rates and improve survival of preterm babies by as much as 84% annually. This is critical in order to achieve the Millennium Development Goal (MDG 4) for child survival by 2015 and beyond.

Antibiotics for ureaplasma in the vagina in pregnancy.

PubMed

Raynes-Greenow, C H; Roberts, C L; Bell, J C; Peat, B; Gilbert, G L

2004-01-01

Preterm birth is a significant obstetric problem in high-income countries. Genital infection including ureaplasmas are suspected of playing a role in preterm birth and preterm rupture of the membranes. Antibiotics are used to treat women with preterm prelabour rupture of the membranes and results in prolongation of pregnancy and lowers the risks of maternal and neonatal infection. However, antibiotics may be beneficial earlier in pregnancy to eradicate potentially causative agents. The objective of this review is to assess whether antibiotic treatment of pregnant women with ureaplasma in the vagina reduces the incidence of preterm birth and other adverse pregnancy outcomes. We searched the Cochrane Pregnancy and Childbirth Group trials register (April 2003). All randomised controlled trials that compared any antibiotic regimen with placebo or no treatment in pregnant women with ureaplasma detected in the vagina. Three reviewers independently assessed eligibility and trial quality and extracted data. One trial involving 1071 women was included. Of these, 644 randomly received antibiotic treatment (174 erythromycin estolate, 224 erythromycin sterate, and 246 clindamycin hydrochloride) and 427 received placebo. This trial did not report data on preterm birth. Incidence of low birthweight less than 2500 grams was only evaluated for erythromycin (combined) (n = 398 ) compared to placebo (n = 427) and there was no statistically significant difference between those treated and those not treated (relative risk (RR) 0.70, 95% confidence interval (CI) 0.46 to 1.07). In regards to side-effects sufficient to stop treatment, data were available for all women, and there were no statistically significant differences between any antibiotic (combined) and the placebo group (RR 1.25, 95% CI 0.85 to 1.85). There is insufficient evidence to show whether giving antibiotics to women with ureaplasma in the vagina will prevent preterm birth.

An M1-like Macrophage Polarization in Decidual Tissue during Spontaneous Preterm Labor That Is Attenuated by Rosiglitazone Treatment.

PubMed

Xu, Yi; Romero, Roberto; Miller, Derek; Kadam, Leena; Mial, Tara N; Plazyo, Olesya; Garcia-Flores, Valeria; Hassan, Sonia S; Xu, Zhonghui; Tarca, Adi L; Drewlo, Sascha; Gomez-Lopez, Nardhy

2016-03-15

Decidual macrophages are implicated in the local inflammatory response that accompanies spontaneous preterm labor/birth; however, their role is poorly understood. We hypothesized that decidual macrophages undergo a proinflammatory (M1) polarization during spontaneous preterm labor and that PPARγ activation via rosiglitazone (RSG) would attenuate the macrophage-mediated inflammatory response, preventing preterm birth. In this study, we show that: 1) decidual macrophages undergo an M1-like polarization during spontaneous term and preterm labor; 2) anti-inflammatory (M2)-like macrophages are more abundant than M1-like macrophages in decidual tissue; 3) decidual M2-like macrophages are reduced in preterm pregnancies compared with term pregnancies, regardless of the presence of labor; 4) decidual macrophages express high levels of TNF and IL-12 but low levels of peroxisome proliferator-activated receptor γ (PPARγ) during spontaneous preterm labor; 5) decidual macrophages from women who underwent spontaneous preterm labor display plasticity by M1↔M2 polarization in vitro; 6) incubation with RSG reduces the expression of TNF and IL-12 in decidual macrophages from women who underwent spontaneous preterm labor; and 7) treatment with RSG reduces the rate of LPS-induced preterm birth and improves neonatal outcomes by reducing the systemic proinflammatory response and downregulating mRNA and protein expression of NF-κB, TNF, and IL-10 in decidual and myometrial macrophages in C57BL/6J mice. In summary, we demonstrated that decidual M1-like macrophages are associated with spontaneous preterm labor and that PPARγ activation via RSG can attenuate the macrophage-mediated proinflammatory response, preventing preterm birth and improving neonatal outcomes. These findings suggest that the PPARγ pathway is a new molecular target for future preventative strategies for spontaneous preterm labor/birth. Copyright © 2016 by The American Association of Immunologists, Inc.

Use of continuous electronic fetal monitoring in a preterm fetus: clinical dilemmas and recommendations for practice.

PubMed

Afors, Karolina; Chandraharan, Edwin

2011-01-01

The aim of intrapartum continuous electronic fetal monitoring using a cardiotocograph (CTG) is to identify a fetus exposed to intrapartum hypoxic insults so that timely and appropriate action could be instituted to improve perinatal outcome. Features observed on a CTG trace reflect the functioning of somatic and autonomic nervous systems and the fetal response to hypoxic or mechanical insults during labour. Although, National Guidelines on electronic fetal monitoring exist for term fetuses, there is paucity of recommendations based on scientific evidence for monitoring preterm fetuses during labour. Lack of evidence-based recommendations may pose a clinical dilemma as preterm births account for nearly 8% (1 in 13) live births in England and Wales. 93% of these preterm births occur after 28 weeks, 6% between 22-27 weeks, and 1% before 22 weeks. Physiological control of fetal heart rate and the resultant features observed on the CTG trace differs in the preterm fetus as compared to a fetus at term making interpretation difficult. This review describes the features of normal fetal heart rate patterns at different gestations and the physiological responses of a preterm fetus compared to a fetus at term. We have proposed an algorithm "ACUTE" to aid management.

Preterm birth-associated cost of early intervention services: an analysis by gestational age.

PubMed

Clements, Karen M; Barfield, Wanda D; Ayadi, M Femi; Wilber, Nancy

2007-04-01

Characterizing the cost of preterm birth is important in assessing the impact of increasing prematurity rates and evaluating the cost-effectiveness of therapies to prevent preterm delivery. To assess early intervention costs that are associated with preterm births, we estimated the program cost of early intervention services for children who were born in Massachusetts, by gestational age at birth. Using the Pregnancy to Early Life Longitudinal Data Set, birth certificates for infants who were born in Massachusetts between July 1999 and June 2000 were linked to early intervention claims through 2003. We determined total program costs, in 2003 dollars, of early intervention and mean cost per surviving infant by gestational age. Costs by plurality, eligibility criteria, provider discipline, and annual costs for children's first 3 years also were examined. Overall, 14,033 of 76,901 surviving infants received early intervention services. Program costs totaled almost $66 million, with mean cost per surviving infant of $857. Mean cost per infant was highest for children who were 24 to 31 weeks' gestational age ($5393) and higher for infants who were 32 to 36 weeks' gestational age ($1578) compared with those who were born at term ($725). Cost per surviving infant generally decreased with increasing gestational age. Among children in early intervention, mean cost per child was higher for preterm infants than for term infants. At each gestational age, mean cost per surviving infant was higher for multiples than for singletons, and annual early intervention costs were higher for toddlers than for infants. Compared with their term counterparts, preterm infants incurred higher early intervention costs. This information along with data on birth trends will inform budget forecasting for early intervention programs. Costs that are associated with early childhood developmental services must be included when considering the long-term costs of prematurity.

Comparison of gestational age classifications: date of last menstrual period vs. clinical estimate.

PubMed

Wingate, Martha S; Alexander, Greg R; Buekens, Pierre; Vahratian, Anjel

2007-06-01

The purpose was to compare the two different measures of gestational age currently used on birth certificates (the duration of pregnancy based on the date of last menstrual period [LMP] and the clinical estimate [CE] as related to health status indicators. We contrasted these measures by race/ethnicity. NCHS natality files for 2000-2002 were used, selecting cases of single live birth to U.S. resident mothers with both LMP and CE gestational age information. Approximately 75% of the records had valid LMP and CE values and for approximately one-half of these, the LMP and CE values did not exactly agree. Overall and for each race and ethnic group, the LMP measures resulted in higher proportions of very preterm, preterm, postterm and SGA births. CE value provided preterm rates of 7.9% and for LMP, 9.9%. The odds ratio of preterm birth for African-Americans using the CE measure was 1.78 [95% Cl 1.77-1.79]. The odds ratio using LMP was 1.93 [95% Cl 1.92-1.94]. Whites were the referent population. Different measures of gestational age result in different overall and race-specific rates of very preterm, preterm, postterm, and SGA births. These findings indicate that substituting or combining these measures may have consequences.

Sustained inflation versus positive pressure ventilation at birth: a systematic review and meta-analysis.

PubMed

Schmölzer, Georg M; Kumar, Manoj; Aziz, Khalid; Pichler, Gerhard; O'Reilly, Megan; Lista, Gianluca; Cheung, Po-Yin

2015-07-01

Sustained inflation (SI) has been advocated as an alternative to intermittent positive pressure ventilation (IPPV) during the resuscitation of neonates at birth, to facilitate the early development of an effective functional residual capacity, reduce atelectotrauma and improve oxygenation after the birth of preterm infants. The primary aim was to review the available literature on the use of SI compared with IPPV at birth in preterm infants for major neonatal outcomes, including bronchopulmonary dysplasia (BPD) and death. MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials, until 6 October 2014. Randomised clinical trials comparing the effects of SI with IPPV at birth in preterm infants for neonatal outcomes. Descriptive and quantitative information was extracted; data were pooled using a random effects model. Heterogeneity was assessed using the Q statistic and I(2). Pooled analysis showed significant reduction in the need for mechanical ventilation within 72 h after birth (relative risk (RR) 0.87 (0.77 to 0.97), absolute risk reduction (ARR) -0.10 (-0.17 to -0.03), number needed to treat 10) in preterm infants treated with an initial SI compared with IPPV. However, significantly more infants treated with SI received treatment for patent ductus arteriosus (RR 1.27 (1.05 to 1.54), ARR 0.10 (0.03 to 0.16), number needed to harm 10). There were no differences in BPD, death at the latest follow-up and the combined outcome of death or BPD among survivors between the groups. Compared with IPPV, preterm infants initially treated with SI at birth required less mechanical ventilation with no improvement in the rate of BPD and/or death. The use of SI should be restricted to randomised trials until future studies demonstrate the efficacy and safety of this lung aeration manoeuvre. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Born a bit too early: recent trends in late preterm births.

PubMed

Martin, Joyce A; Kirmeyer, Sharon; Osterman, Michelle; Shepherd, Ruth A

2009-11-01

The U.S. late preterm birth rate rose 20% from 1990 to 2006. If the late preterm rate had not risen from the 1990 level, more than 50,000 fewer infants would have been delivered late preterm in 2006. On average, more than 900 late preterm babies are born every day in the United States, or a total of one-third of 1 million infants (333,461). Increases in late preterm births are seen for mothers of all ages, and for non-Hispanic white and Hispanic mothers. The rate for black mothers declined during the 1990s, but has been on the rise since 2000. Late preterm birth rates rose for all U.S. states, but declined in the District of Columbia. The percentage of late preterm births for which labor was induced more than doubled from 1990 to 2006; the percentage of late preterm births delivered by cesarean also rose markedly.

Genome-wide association studies in preterm birth: implications for the practicing obstetrician-gynaecologist

PubMed Central

2013-01-01

Preterm birth has the highest mortality and morbidity of all pregnancy complications. The burden of preterm birth on public health worldwide is enormous, yet there are few effective means to prevent a preterm delivery. To date, much of its etiology is unexplained, but genetic predisposition is thought to play a major role. In the upcoming year, the international Preterm Birth Genome Project (PGP) consortium plans to publish a large genome wide association study in early preterm birth. Genome-wide association studies (GWAS) are designed to identify common genetic variants that influence health and disease. Despite the many challenges that are involved, GWAS can be an important discovery tool, revealing genetic variations that are associated with preterm birth. It is highly unlikely that findings of a GWAS can be directly translated into clinical practice in the short run. Nonetheless, it will help us to better understand the etiology of preterm birth and the GWAS results will generate new hypotheses for further research, thus enhancing our understanding of preterm birth and informing prevention efforts in the long run. PMID:23445776

Genome-wide association studies in preterm birth: implications for the practicing obstetrician-gynaecologist.

PubMed

Dolan, Siobhan M; Christiaens, Inge

2013-01-01

Preterm birth has the highest mortality and morbidity of all pregnancy complications. The burden of preterm birth on public health worldwide is enormous, yet there are few effective means to prevent a preterm delivery. To date, much of its etiology is unexplained, but genetic predisposition is thought to play a major role. In the upcoming year, the international Preterm Birth Genome Project (PGP) consortium plans to publish a large genome wide association study in early preterm birth. Genome-wide association studies (GWAS) are designed to identify common genetic variants that influence health and disease. Despite the many challenges that are involved, GWAS can be an important discovery tool, revealing genetic variations that are associated with preterm birth. It is highly unlikely that findings of a GWAS can be directly translated into clinical practice in the short run. Nonetheless, it will help us to better understand the etiology of preterm birth and the GWAS results will generate new hypotheses for further research, thus enhancing our understanding of preterm birth and informing prevention efforts in the long run.

Preterm birth and inflammation-The role of genetic polymorphisms.

PubMed

Holst, Daniela; Garnier, Yves

2008-11-01

Spontaneous preterm labour and preterm births are still the leading cause of perinatal morbidity and mortality in the developed world. Previous efforts to prevent preterm birth have been hampered by a poor understanding of the underlying pathophysiology, inadequate diagnostic tools and generally ineffective therapies. Clinical, epidemiological and experimental studies indicate that genito-urinary tract infections play a critical role in the pathogenesis of preterm birth. Moreover, intrauterine infection increases perinatal mortality and morbidity, such as cerebral palsy and chronic lung disease, significantly. It has recently been suggested that gene-environment interactions play a significant role in determining the risk of preterm birth. Polymorphisms of certain critical genes may be responsible for a harmful inflammatory response in those who possess them. Accordingly, polymorphisms that increase the magnitude or the duration of the inflammatory response were associated with an increased risk of preterm birth. In contrast polymorphisms that decrease the inflammatory response were associated with a lower risk of preterm birth. This article will review the current understanding of pathogenetic pathways in the aetiology of preterm birth.

Rate of gestational weight gain and preterm birth in relation to prepregnancy body mass indices and trimester: a follow-up study in China.

PubMed

Huang, Aiqun; Ji, Zhenpeng; Zhao, Wei; Hu, Huanqing; Yang, Qi; Chen, Dafang

2016-08-12

To evaluate the association between rate of gestational weight gain and preterm birth varying prepregnancy body mass indices and trimester. Data from Maternal and Newborn's Health Monitoring System on 17475 pregnant women who delivered live singletons at ≥ 28 weeks of gestation between October 2013 and September 2014 from 12 districts/counties of 6 provinces in China and started prenatal care at ≤ 12 weeks of gestation was analyzed. Gestational weight gain was categorized by rate of weight gain during the 2(nd) and 3(rd) trimester, based on the 2009 Institute of Medicine guidelines. Multivariable binary logistic regression models were conducted to investigate the association between rate of gestational weight gain and preterm birth stratified by prepregnancy body mass indices and trimester. Excessive weight gain occurred in 57.9 % pregnant women, and insufficient weight gain 12.5 %. Average rate of gestational weight gain in 2(nd) and 3(rd) trimester was independently associated with preterm birth (U-shaped), and the association varied by prepregnancy body mass indices and trimesters. In underweight women, excessive gestational weight gain was positively associated with preterm birth (OR 1.93, 95 % confidence interval (CI): 1.29- 2.88) when compared with women who gained adequately. While in overweight/obese women, insufficient gestational weight gain was positively associated with preterm birth (OR 3.92, 95 % CI: 1.13-13.67). When stratifying by trimester, we found that excessive weight gain in 3(rd) trimester had a significantly positive effect on preterm birth (OR 1.27, 95 % CI: 1.02-1.58). Excessive gestational weight gain among underweight pregnant women, insufficient gestational weight gain among overweight/obese women and excessive gestational weight gain in 3(rd) trimester were important predictors of preterm birth.

Incidence of short stature at 3 years of age in late preterm infants: a population-based study.

PubMed

Nagasaka, Miwako; Morioka, Ichiro; Yokota, Tomoyuki; Fujita, Kaori; Kurokawa, Daisuke; Koda, Tsubasa; Shibata, Akio; Yamada, Hideto; Ito, Yoshiya; Uchino, Eiko; Shirai, Chika; Iijima, Kazumoto

2015-03-01

This study aimed to investigate the incidence of short stature at 3 years of age in a Japanese cohort of late preterm infants who were born at 34-36 weeks' gestational age (GA). We compared these late preterm infants with term infants (37-41 weeks' GA), and evaluated the effect of birth weight on the incidence of short stature. A longitudinal population-based study of 26 970 neonates who were born between 34 weeks' and 41 weeks' GA in 2006-2008 was conducted in Kobe, Japan. Of these neonates, 1414 were late preterm and 25 556 were term infants. The late preterm infants were then divided into three subgroups based on birth weight as determined by Japanese neonatal anthropometric charts for GA at birth: large-for-GA (n=140), appropriate-for-GA (AGA, n=1083), and small-for-GA (SGA, n=191). The incidence of short stature at 3 years of age was calculated in the late preterm group and compared with that in the term group, and between the AGA and SGA groups with late preterm birth. The incidence of short stature in the late preterm group was 2.9%, which was significantly higher than that in the term group (1.4%). Late preterm SGA infants developed short stature with a significantly higher (9.4%) incidence than that of late preterm AGA infants (2.1%). The incidence of short stature in 3-year-old children who were late preterm infants has a 2-fold higher risk than that in term infants. The risk of developing short stature is increased 4.5-fold if they are SGA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The role of inflammation in preterm birth--focus on periodontitis.

PubMed

Klebanoff, M; Searle, K

2006-12-01

It is universally accepted that acute inflammation is responsible for a substantial fraction of preterm births, particularly early cases. Much of this inflammation is caused by intrauterine infection. There is also evidence that infection and perhaps inflammation remote from the genitourinary tract can trigger preterm labour. Several studies have suggested that periodontitis during pregnancy increases the risk of preterm birth. Periodontitis may cause preterm birth by causing low-grade bacteraemia, which lodges in the decidua, chorion and amnion or by releasing endotoxin into the maternal circulation, which triggers intrauterine inflammation and preterm birth. Alternatively, it may release cytokines and other inflammatory products, which then trigger preterm labour. It is also conceivable that periodontitis might serve as a marker for other unhealthy behaviours, or immune hyperresponsiveness and that hyperresponsiveness to low-grade intrauterine infection itself might cause preterm birth. Currently, there are few data available to distinguish these possibilities. Such distinctions are important since they have clear implications for whether treatment of periodontitis might reduce the incidence of preterm birth. Several clinical trials of treatment of periodontitis are continuing, but until their results are known there is currently little evidence that treatment of periodontitis during pregnancy reduces the incidence of preterm birth.

Endometriosis, assisted reproduction technology, and risk of adverse pregnancy outcome.

PubMed

Stephansson, Olof; Kieler, Helle; Granath, Fredrik; Falconer, Henrik

2009-09-01

Endometriosis, a common gynaecological disease, is characterized by local and systemic inflammation, which may cause infertility and consequently, increased utilization of assisted reproduction technology (ART). We aimed to estimate the risk for preterm birth, small-for-gestational-age (SGA) birth, stillbirth, Caesarean section, pre-eclampsia and antepartal haemorrhage among women with a previous diagnosis of endometriosis compared with women with no previous diagnosis of endometriosis. In a nationwide Swedish study including 1,442,675 singleton births we assessed the association between adverse pregnancy outcome, ART and a previous diagnosis of endometriosis. Information was obtained by linkage of data between 1992 and 2006 in the Medical Birth Register with the Patient Register between 1964 and 2006. There were 13,090 singleton births among 8922 women diagnosed with endometriosis. Compared with women without endometriosis, women with endometriosis had higher risks of preterm birth [adjusted odds ratio 1.33, 95% confidence interval (CI), 1.23-1.44]. Among women with endometriosis 11.9% conceived after ART compared with 1.4% of women without endometriosis. The risk of preterm birth associated with endometriosis among women with ART was 1.24 (95% CI, 0.99-1.57), and among women without ART 1.37 (95% CI, 1.25-1.50). Women with endometriosis had higher risks of antepartal bleeding/placental complications, pre-eclampsia and Caesarean section. There was no association between endometriosis and risk of SGA-birth or stillbirth. Endometriosis appears to be a risk factor for preterm birth, irrespective of ART. Women with endometriosis may be more likely to be delivered by Caesarean section and to suffer from antepartal haemorrhage/placental complications and pre-eclampsia.

Recurrence of preterm birth and perinatal mortality in northern Tanzania: registry-based cohort study.

PubMed

Mahande, Michael J; Daltveit, Anne K; Obure, Joseph; Mmbaga, Blandina T; Masenga, Gileard; Manongi, Rachel; Lie, Rolv T

2013-08-01

To estimate the recurrence risk of preterm delivery and estimate the perinatal mortality in repeated preterm deliveries. Prospective study in Tanzania of 18 176 women who delivered a singleton between 2000 and 2008 at KCMC hospital. The women were followed up to 2010 for consecutive births. A total of 3359 women were identified with a total of 3867 subsequent deliveries in the follow-up period. Recurrence risk of preterm birth and perinatal mortality was estimated using log-binomial regression and adjusted for potential confounders. For women with a previous preterm birth, the risk of preterm birth in a subsequent pregnancy was 17%. This recurrence risk was estimated to be 2.7-fold (95% CI: 2.1-3.4) of the risk of women with a previous term birth. The perinatal mortality of babies in a second preterm birth of the same woman was 15%. Babies born at term who had an older sibling that was born preterm had a perinatal mortality of 10%. Babies born at term who had an older sibling who was also born at term had a perinatal mortality of 1.7%. Previous delivery of a preterm infant is a strong predictor of future preterm births in Tanzania. Previous or repeated preterm births increase the risk of perinatal death substantially in the subsequent pregnancy. © 2013 Blackwell Publishing Ltd.

Progesterone to prevent spontaneous preterm birth

PubMed Central

Romero, Roberto; Yeo, Lami; Chaemsaithong, Piya; Chaiworapongsa, Tinnakorn; Hassan, Sonia

2014-01-01

Summary Preterm birth is the leading cause of perinatal morbidity and mortality worldwide, and its prevention is an important healthcare priority. Preterm parturition is one of the ‘great obstetrical syndromes’ and is caused by multiple etiologies. One of the mechanisms of disease is the untimely decline in progesterone action, which can be manifested by a sonographic short cervix in the midtrimester. The detection of a short cervix in the midtrimester is a powerful risk factor for preterm delivery. Vaginal progesterone can reduce the rate of preterm delivery by 45%, and the rate of neonatal morbidity (admission to neonatal intensive care unit, respiratory distress syndrome, need for mechanical ventilation, etc.). To prevent one case of spontaneous preterm birth <33 weeks of gestation, 12 patients with a short cervix would need to be treated. Vaginal progesterone reduces the rate of spontaneous preterm birth in women with a short cervix both with and without a prior history of preterm birth. In patients with a prior history of preterm birth, vaginal progesterone is as effective as cervical cerclage to prevent preterm delivery. 17α-Hydroxyprogesterone caproate has not been shown to be effective in reducing the rate of spontaneous preterm birth in women with a short cervix. PMID:24315687

Recent advances in the prevention and management of preterm birth

PubMed Central

Tan, Min Yi

2015-01-01

The management of preterm birth has seen major transformations in the last few decades with increasing interest worldwide, due to the impact of preterm birth on neonatal morbidity and mortality. The prevention strategies currently available for asymptomatic women at risk of preterm birth include progesterone, cervical cerclage and cervical pessary. Each approach has varying effects depending on the patient's prior history of preterm birth, cervical length and the presence of multiple gestations. There is a shift in the focus of antenatal treatment, with the use of prenatal magnesium sulphate and corticosteroids, to reduce neonatal intensive care admissions and longer-term disabilities associated with preterm birth, consequently relieving emotional and economical burden. This article provides an update on the recent advances in prevention and management approaches available for women at risk of preterm birth. PMID:26097713

Microstructural and functional connectivity in the developing preterm brain

PubMed Central

Lubsen, Julia; Vohr, Betty; Myers, Eliza; Hampson, Michelle; Lacadie, Cheryl; Schneider, Karen C.; Katz, Karol H.; Constable, R. Todd; Ment, Laura R.

2011-01-01

Prematurely born children are at increased risk for cognitive deficits, but the neurobiological basis of these findings remains poorly understood. Since variations in neural circuitry may influence performance on cognitive tasks, recent investigations have explored the impact of preterm birth on connectivity in the developing brain. Diffusion tensor imaging studies demonstrate widespread alterations in fractional anisotropy, a measure of axonal integrity and microstructural connectivity, throughout the developing preterm brain. Functional connectivity studies report that preterm neonates, children and adolescents exhibit alterations in both resting state and task-based connectivity when compared to term control subjects. Taken together, these data suggest that neurodevelopmental impairment following preterm birth may represent a disease of neural connectivity. PMID:21255705

Preterm birth and attention-deficit/hyperactivity disorder in schoolchildren.

PubMed

Lindström, Karolina; Lindblad, Frank; Hjern, Anders

2011-05-01

Previous studies have demonstrated an increased risk for attention-deficit/hyperactivity disorder (ADHD) in follow-up studies of preterm survivors from NICUs. In this study we analyzed the effect of moderate as well as extreme preterm birth on the risk for ADHD in school age, taking into account genetic, perinatal, and socioeconomic confounders. Register study in a Swedish national cohort of 1 180 616 children born between 1987 and 2000, followed up for ADHD medication in 2006 at the age of 6 to 19 years. Logistic regression was used to test hypotheses. A within-mother-between-pregnancy design was used to estimate the importance of genetic confounding in a subpopulation of offspring (N = 34 334) of mothers who had given birth to preterm (≤34 weeks) as well as term infants. There was a stepwise increase in odds ratios for ADHD medication with increasing degree of immaturity at birth; from 2.1 (1.4-2.7) for 23 to 28 weeks' gestation, to 1.6 (1.4-1.7) for 29 to 32 weeks', 1.4 (1.2-1.7) for 33 to 34 weeks', 1.3 (1.1-1.4) for 35 to 36 weeks', and 1.1 (1.1-1.2) for 37 to 38 weeks' gestation compared with infants born at 39 to 41 weeks' gestation in the fully adjusted model. The odds ratios for the within-mother-between-pregnancy analysis were very similar. Low maternal education increased the effect of moderate, but not extreme, preterm birth on the risk for ADHD. Preterm and early term birth increases the risk of ADHD by degree of immaturity. This main effect is not explained by genetic, perinatal, or socioeconomic confounding, but socioeconomic context modifies the risk of ADHD in moderately preterm births.

Prenatal care and infant birth outcomes among Medicaid recipients.

PubMed

Guillory, V James; Samuels, Michael E; Probst, Janice C; Sharp, Glynda

2003-05-01

Infant morbidity due to low birth weight and preterm births results in emotional suffering and significant direct and indirect costs. African American infants continue to have worse birth outcomes than white infants. This study examines relationships between newborn hospital costs, maternal risk factors, and prenatal care in Medicaid recipients in an impoverished rural county in South Carolina. Medicaid African American mothers gave birth to fewer preterm infants than did non-Medicaid African American mothers. No differences in the rates of preterm infants were noted between white and African American mothers in the Medicaid group. Access to Medicaid services may have contributed to this reduction in disparities due to race. Early initiation of prenatal care compared with later initiation did not improve birth outcomes. Infants born to mothers who initiated prenatal care early had increased morbidity with increased utilization of hospital services, suggesting that high-risk mothers are entering prenatal care earlier.

Racial and Ethnic Disparities in Preterm Birth Among American Indian and Alaska Native Women.

PubMed

Raglan, Greta B; Lannon, Sophia M; Jones, Katherine M; Schulkin, Jay

2016-01-01

Preterm birth disproportionately affects American Indian/Alaska Native (AI/AN) women. This disparity in birth outcomes may stem from higher levels of exposure to psychosocial, sociodemographic, and medical risk factors. This paper reviews relevant research related to preterm birth in American Indian and Alaska Native women. This narrative review examines disparities in preterm birth rates between AI/AN and other American women, and addresses several maternal risk factors and barriers that contribute to elevated preterm birth rates among this racial minority group. Additionally, this paper focuses on recent evidence that geographical location can significantly impact preterm birth rates among AI/AN women. In particular, access to care among AI/AN women and differences between rural and urban areas are discussed.

Correcting haemoglobin cut-offs to define anaemia in high-altitude pregnant women in Peru reduces adverse perinatal outcomes.

PubMed

Gonzales, Gustavo F; Tapia, Vilma; Gasco, Manuel

2014-07-01

To determine if correction of cut-offs of haemoglobin levels to define anaemia at high altitudes affects rates of adverse perinatal outcomes. Data were obtained from 161,909 mothers and newborns whose births occurred between 1,000 and 4,500 m above sea level (masl). Anaemia was defined with or without correction of haemoglobin (Hb) for altitude as Hb <11 g/dL. Correction of haemoglobin per altitude was performed according to guidelines from the World Health Organization. Rates of stillbirths and preterm births were also calculated. Stillbirth and preterm rates were significantly reduced in cases of anaemia calculated after correction of haemoglobin for altitude compared to values obtained without Hb correction. At high altitudes (3,000-4,500 masl), after Hb correction, the rate of stillbirths was reduced from 37.7 to 18.3 per 1,000 live births (p < 0.01); similarly, preterm birth rates were reduced from 13.1 to 8.76 % (p < 0.01). The odds ratios for stillbirths and for preterm births were also reduced after haemoglobin correction. At high altitude, correction of maternal haemoglobin should not be performed to assess the risks for preterm birth and stillbirth. In fact, using low altitude Hb cut-off is associated with predicting those at risk.

Temporal Trends in Late Preterm and Early Term Birth Rates in 6 High-Income Countries in North America and Europe and Association With Clinician-Initiated Obstetric Interventions.

PubMed

Richards, Jennifer L; Kramer, Michael S; Deb-Rinker, Paromita; Rouleau, Jocelyn; Mortensen, Laust; Gissler, Mika; Morken, Nils-Halvdan; Skjærven, Rolv; Cnattingius, Sven; Johansson, Stefan; Delnord, Marie; Dolan, Siobhan M; Morisaki, Naho; Tough, Suzanne; Zeitlin, Jennifer; Kramer, Michael R

2016-07-26

Clinicians have been urged to delay the use of obstetric interventions (eg, labor induction, cesarean delivery) until 39 weeks or later in the absence of maternal or fetal indications for intervention. To describe recent trends in late preterm and early term birth rates in 6 high-income countries and assess association with use of clinician-initiated obstetric interventions. Retrospective analysis of singleton live births from 2006 to the latest available year (ranging from 2010 to 2015) in Canada, Denmark, Finland, Norway, Sweden, and the United States. Use of clinician-initiated obstetric intervention (either labor induction or prelabor cesarean delivery) during delivery. Annual country-specific late preterm (34-36 weeks) and early term (37-38 weeks) birth rates. The study population included 2,415,432 Canadian births in 2006-2014 (4.8% late preterm; 25.3% early term); 305,947 Danish births in 2006-2010 (3.6% late preterm; 18.8% early term); 571,937 Finnish births in 2006-2015 (3.3% late preterm; 16.8% early term); 468,954 Norwegian births in 2006-2013 (3.8% late preterm; 17.2% early term); 737,754 Swedish births in 2006-2012 (3.6% late preterm; 18.7% early term); and 25,788,558 US births in 2006-2014 (6.0% late preterm; 26.9% early term). Late preterm birth rates decreased in Norway (3.9% to 3.5%) and the United States (6.8% to 5.7%). Early term birth rates decreased in Norway (17.6% to 16.8%), Sweden (19.4% to 18.5%), and the United States (30.2% to 24.4%). In the United States, early term birth rates decreased from 33.0% in 2006 to 21.1% in 2014 among births with clinician-initiated obstetric intervention, and from 29.7% in 2006 to 27.1% in 2014 among births without clinician-initiated obstetric intervention. Rates of clinician-initiated obstetric intervention increased among late preterm births in Canada (28.0% to 37.9%), Denmark (22.2% to 25.0%), and Finland (25.1% to 38.5%), and among early term births in Denmark (38.4% to 43.8%) and Finland (29.8% to 40.1%). Between 2006 and 2014, late preterm and early term birth rates decreased in the United States, and an association was observed between early term birth rates and decreasing clinician-initiated obstetric interventions. Late preterm births also decreased in Norway, and early term births decreased in Norway and Sweden. Clinician-initiated obstetric interventions increased in some countries but no association was found with rates of late preterm or early term birth.

Impaired Cerebellar Maturation, Growth Restriction, and Circulating Insulin-Like Growth Factor 1 in Preterm Rabbit Pups

PubMed Central

Sveinsdóttir, Kristbjörg; Länsberg, John-Kalle; Sveinsdóttir, Snjólaug; Garwicz, Martin; Ohlsson, Lennart; Hellström, Ann; Smith, Lois; Gram, Magnus; Ley, David

2018-01-01

Cerebellar growth is impeded following very preterm birth in human infants and the observed reduction in cerebellar volume is associated with neurodevelopmental impairment. Decreased levels of circulating insulin-like growth factor 1 (IGF-1) are associated with decreased cerebellar volume. The relationship between preterm birth, circulating IGF-1, and key cell populations supporting cerebellar proliferation is unknown. The aim of this study was to evaluate the effect of preterm birth on postnatal growth, circulating IGF-1, and cerebellar maturation in a preterm rabbit pup model. Preterm rabbit pups (PT) were delivered by cesarean section at day 29 of gestation, cared for in closed incubators with humidified air, and gavage fed with formula. Control term pups (T) delivered by spontaneous vaginal delivery at day 32 of gestation were housed and fed by their lactating doe. In vivo perfusion-fixation for immunohistochemical evaluation of cerebellar proliferation, cell maturation, and apoptosis was performed at repeated time points in PT and T pups. Results show that the mean weight of the pups and circulating IGF-1 protein levels were lower in the PT group at all time points (p < 0.05) than in the T group. Postnatal weight development correlated with circulating IGF-1 (r2 = 0.89) independently of gestational age at birth and postnatal age. The proliferative (Ki-67-positive) portion of the external granular layer (EGL) was decreased in the PT group at postnatal day 2 (P2) compared to in the T group (p = 0.01). Purkinje cells exhibited decreased calbindin staining at P0 (p = 0.003), P2 (p = 0.004), and P5 (p = 0.04) in the PT group compared to in the T group. Staining for sonic hedgehog was positive in neuronal EGL progenitors and Purkinje cells at early time points but was restricted to a well-defined Purkinje cell monolayer at later time points. Preterm birth in rabbit pups is associated with lower circulating levels of IGF-1, decreased postnatal growth, and decreased cerebellar EGL proliferation and Purkinje cell maturation. The preterm rabbit pup model exhibits important characteristics of human preterm birth, and may thus be suitable for the evaluation of interventions aiming to modify growth and cerebellar development in the preterm population. PMID:28972955

Plastic bags for prevention of hypothermia in preterm and low birth weight infants.

PubMed

Leadford, Alicia E; Warren, Jamie B; Manasyan, Albert; Chomba, Elwyn; Salas, Ariel A; Schelonka, Robert; Carlo, Waldemar A

2013-07-01

Hypothermia contributes to neonatal mortality and morbidity, especially in preterm and low birth weight infants in developing countries. Plastic bags covering the trunk and extremities of very low birth weight infants reduces hypothermia. This technique has not been studied in larger infants or in many resource-limited settings. The objective was to determine if placing preterm and low birth weight infants inside a plastic bag at birth maintains normothermia. Infants at 26 to 36 weeks' gestational age and/or with a birth weight of 1000 to 2500 g born at the University Teaching Hospital in Lusaka, Zambia, were randomized by using a 1:1 allocation and parallel design to standard thermoregulation (blanket or radiant warmer) care or to standard thermoregulation care plus placement inside a plastic bag at birth. The primary outcome measure was axillary temperature in the World Health Organization-defined normal range (36.5-37.5°C) at 1 hour after birth. A total of 104 infants were randomized. At 1 hour after birth, infants randomized to plastic bag (n = 49) were more likely to have a temperature in the normal range as compared with infants in the standard thermoregulation care group (n = 55; 59.2% vs 32.7%; relative risk 1.81; 95% confidence interval 1.16-2.81; P = .007). The temperature at 1 hour after birth in the infants randomized to plastic bag was 36.5 ± 0.5°C compared with 36.1 ± 0.6°C in standard care infants (P < .001). Hyperthermia (>38.0°C) did not occur in any infant. Placement of preterm/low birth weight infants inside a plastic bag at birth compared with standard thermoregulation care reduced hypothermia without resulting in hyperthermia, and is a low-cost, low-technology tool for resource-limited settings.

Plastic Bags for Prevention of Hypothermia in Preterm and Low Birth Weight Infants

PubMed Central

Leadford, Alicia E.; Warren, Jamie B.; Manasyan, Albert; Chomba, Elwyn; Salas, Ariel A.; Schelonka, Robert

2013-01-01

BACKGROUND AND OBJECTIVES: Hypothermia contributes to neonatal mortality and morbidity, especially in preterm and low birth weight infants in developing countries. Plastic bags covering the trunk and extremities of very low birth weight infants reduces hypothermia. This technique has not been studied in larger infants or in many resource-limited settings. The objective was to determine if placing preterm and low birth weight infants inside a plastic bag at birth maintains normothermia. METHODS: Infants at 26 to 36 weeks’ gestational age and/or with a birth weight of 1000 to 2500 g born at the University Teaching Hospital in Lusaka, Zambia, were randomized by using a 1:1 allocation and parallel design to standard thermoregulation (blanket or radiant warmer) care or to standard thermoregulation care plus placement inside a plastic bag at birth. The primary outcome measure was axillary temperature in the World Health Organization–defined normal range (36.5–37.5°C) at 1 hour after birth. RESULTS: A total of 104 infants were randomized. At 1 hour after birth, infants randomized to plastic bag (n = 49) were more likely to have a temperature in the normal range as compared with infants in the standard thermoregulation care group (n = 55; 59.2% vs 32.7%; relative risk 1.81; 95% confidence interval 1.16–2.81; P = .007). The temperature at 1 hour after birth in the infants randomized to plastic bag was 36.5 ± 0.5°C compared with 36.1 ± 0.6°C in standard care infants (P < .001). Hyperthermia (>38.0°C) did not occur in any infant. CONCLUSIONS: Placement of preterm/low birth weight infants inside a plastic bag at birth compared with standard thermoregulation care reduced hypothermia without resulting in hyperthermia, and is a low-cost, low-technology tool for resource-limited settings. PMID:23733796

Audit of Cardiac Surgery Outcomes for Low Birth Weight and Premature Infants.

PubMed

Alarcon Manchego, Peter; Cheung, Michael; Zannino, Diana; Nunn, Russell; D'Udekem, Yves; Brizard, Christian

2018-01-01

The burden of disease associated with cardiac surgery in preterm and low birth weight infants is increasing. This retrospective study aimed to compare the mortality and morbidity of cardiac surgery in low birth weight and preterm infants with that of a case-matched normal population. This was a single-center audit of cardiac surgery interventions at a tertiary pediatric center in Melbourne, Australia. Subjects underwent intervention in the first 3 months of life and were preterm (<37 weeks' gestation) or <2500 g at birth. Subjects were case-matched with 2 controls of term gestation and appropriate birth weight with the same primary diagnosis and intervention. Principal outcomes were mortality and complications in the 6 months following intervention. A total of 513 participants were included for analysis in the 13-year study period. There was an increased risk of mortality (odds ratio 6.26; 95% confidence interval (3.19, 12.3)) and rate of complications (odds ratio 2.29; 95% confidence interval (1.38, 3.78)) in low birth weight and premature infants compared with the control population. Patients who did not survive were more likely to have required extracorporeal membrane oxygenation (relative risk [RR] 6.6, P < 0.001), developed postoperative sepsis (RR 2.6, P = 0.012), and undergone unplanned reintervention (RR 2.3, P < 0.001) compared with survivors. Preterm and low birth weight patients had twice the RR of developing complications and 6 times the risk of mortality in the 6 months following cardiac intervention compared with a matched population. Observed trends suggest delaying surgery in clinically stable infants beyond 35 weeks corrected gestational age and 2500-g weight may result in improved survival. Copyright © 2018 Elsevier Inc. All rights reserved.

Static balance function in children with a history of preterm birth

PubMed Central

Eshaghi, Zahra; Jafari, Zahra; Jalaie, Shohreh

2015-01-01

Background: The incomplete maturation of brain in preterm children results in long-term neurodevelopmental impairment. This study aimed to investigate the static balance function in children with a history of preterm birth. Methods: Participants were 31 preterm children including 21 moderately preterm (MPT), 10 very preterm (VPT), and 20 term children aged 5.5 and 6.5 years. The cervical vestibular-evoked myogenic potential (cVEMP) test and four static balance subscales of BOT-2 were performed. Results: The VPT children showed a significant increase in P1 and N1 wave latencies in cVEMP test compared to those in the term children (p= 0.041). Mean scores in the four static balance subscales of BOT-2 were significantly lower in the preterm children compared to those in the term children (p= 0.025). The P1 wave latency (p= 0.003) and mean score of standing on a balance beam with open eyes (p= 0.039) were significantly lower in the VPT children compared to those in the MPT children. A significant correlation was observed between the mean score in exercise 4 (standing on one leg on a balance beam with closed eyes) of static balance subscales of BOT-2 and P1 (r= -0.267, p= 0.036) and N1 (r= -0.304, p= 0.016) wave latencies of cVEMP. Conclusion: The longer latency of cVEMP waves along with a poor performance of children with a history of preterm birth suggests a possible defect in central vestibular pathway. PMID:26913273

Paternal and maternal birthweights and the risk of infant preterm birth.

PubMed

Klebanoff, Mark A

2008-01-01

Increasing paternal birthweight has been associated with increased risk of fathering a preterm infant, causing speculation that a fetus programmed to grow rapidly can trigger preterm labor. Pregnancies occurring from 1974-1989 among women themselves born in the Danish Perinatal Study (1959-1961) were identified through the Population Register; obstetric records were abstracted. Paternal birthweight was obtained by linking Personal Identification Numbers of the fathers to archived midwifery records. Paternal birthweight was not associated with preterm infants overall. However, there was a significant interaction between paternal and maternal birthweights (P = .003). When the mother weighed less than 3 kg at birth, increasing paternal birthweight was associated with increased occurrence of preterm birth (P for trend = .02); paternal birthweight was unassociated with preterm birth for mothers weighing 3 kg or more at birth (P = .34). When the mother was born small, increasing paternal birthweight was associated with increased risk of preterm birth, suggesting that a fetus growing faster than its mother can accommodate might trigger preterm birth.

CDC Grand Rounds: Public Health Strategies to Prevent Preterm Birth.

PubMed

Shapiro-Mendoza, Carrie K; Barfield, Wanda D; Henderson, Zsakeba; James, Arthur; Howse, Jennifer L; Iskander, John; Thorpe, Phoebe G

2016-08-19

Preterm birth (delivery before 37 weeks and 0/7 days of gestation) is a leading cause of infant morbidity and mortality in the United States. In 2013, 11.4% of the nearly 4 million U.S. live births were preterm; however, 36% of the 8,470 infant deaths were attributed to preterm birth (1). Infants born at earlier gestational ages, especially <32 0/7 weeks, have the highest mortality (Figure) and morbidity rates. Morbidity associated with preterm birth includes respiratory distress syndrome, necrotizing enterocolitis, and intraventricular hemorrhage; longer-term consequences include developmental delay and decreased school performance. Risk factors for preterm delivery include social, behavioral, clinical, and biologic characteristics (Box). Despite advances in medical care, racial and ethnic disparities associated with preterm birth persist. Reducing preterm birth, a national public health priority (2), can be accomplished by implementing and monitoring strategies that target modifiable risk factors and populations at highest risk, and by providing improved quality and access to preconception, prenatal, and interconception care through implementation of strategies with potentially high impact.

Influence of cryopreservation on perinatal outcome after blastocyst- vs cleavage-stage embryo transfer: systematic review and meta-analysis.

PubMed

Alviggi, C; Conforti, A; Carbone, I F; Borrelli, R; de Placido, G; Guerriero, S

2018-01-01

To compare the perinatal outcomes of singleton pregnancies resulting from blastocyst- vs cleavage-stage embryo transfer and to assess whether they differ between fresh and frozen embryo transfer cycles. A systematic review of the literature was carried out using the Scopus, MEDLINE and ISI Web of Science databases with no time restriction. We included only peer-reviewed articles involving humans, in which perinatal outcomes of singleton pregnancies after blastocyst-stage embryo transfer were compared with those after cleavage-stage embryo transfer. Primary outcomes were preterm birth before 37 weeks and low birth weight (< 2500 g). Secondary outcomes were very preterm birth before 32 weeks, very low birth weight (< 1500 g), small-for-gestational-age (SGA), large-for-gestational-age (LGA), perinatal mortality and congenital anomaly. A meta-analysis was performed using a random-effects model. Three subgroups were evaluated: fresh only, frozen only and fresh plus frozen embryo transfer cycles. From a total of 3928 articles identified, 14 were selected for qualitative/quantitative analysis. Significantly higher incidences of preterm birth < 37 weeks (11 studies, n = 106 629 participants; risk ratio (RR), 1.15 (95% CI, 1.05 - 1.25); P = 0.002) and very preterm birth < 32 weeks (seven studies, n = 103 742; RR, 1.16 (95% CI, 1.02-1.31); P = 0.03) were observed after blastocyst- than after cleavage-stage embryo transfer in fresh cycles. However, the risk of preterm and very preterm birth was similar after blastocyst- and cleavage-stage transfers in frozen and fresh plus frozen cycles. Overall effect size analysis revealed fewer SGA deliveries after blastocyst- compared with cleavage-stage transfer in fresh cycles but a similar number in frozen cycles. Conversely, more LGA deliveries were observed after blastocyst- compared with cleavage-stage transfer in frozen cycles (two studies, n = 39 044; RR, 1.18 (95% CI, 1.09-1.27); P < 0.0001) and no differences between the two groups in fresh cycles (four studies, n = 42 982; RR, 1.14 (95% CI, 0.97-1.35); P = 0.11). There were no differences with respect to low birth weight, very low birth weight or congenital anomalies between blastocyst- and cleavage-stage transfers irrespective of the cryopreservation method employed. Only one study reported a higher incidence of perinatal mortality after blastocyst- vs cleavage-stage embryo transfer in frozen cycles, while no differences were found in fresh cycles. Our results suggest that cryopreservation of embryos can influence outcome of pregnancy conceived following blastocyst- vs cleavage-stage embryo transfer in terms of preterm birth, very preterm birth, LGA, SGA and perinatal mortality. Caution should be exercised in interpreting these findings given the low level of evidence and wide heterogeneity of the studies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

What is the impact of interventions that prevent fetal mortality on the increase of preterm live births in the State of Sao Paulo, Brazil?

PubMed

Alencar, Gizelton Pereira; da Silva, Zilda Pereira; Santos, Patrícia Carla; Raspantini, Priscila Ribeiro; Moura, Barbara Laisa Alves; de Almeida, Marcia Furquim; do Nascimento, Felipe Parra; Rodrigues, Laura C

2015-07-23

There is a global growing trend of preterm births and a decline trend of fetal deaths. Is there an impact of the decline of fetal mortality on the increase of preterm live births in State of Sao Paulo, Brazil? The time trends were evaluated by gestational age through exponential regression analysis. Data analyzed included the fetal mortality ratio, proportion of preterm live births, fertility rate of women 35 years and over, prenatal care, mother's education, multiple births and cesarean section deliveries. A survival analysis was carried out for 2000 and 2010. Preterm births showed the highest annual increase (3.2%) in the less than 28 weeks of gestation group and fetal mortality ratio decreased (7.4%) in the same gestational age group. There was an increase of cesarean section births and it was higher in the < 28 weeks group (6.1%). There was a decreased annual trend of mothers with inadequate prenatal care (6.1%) and low education (8.8%) and an increased trend in multiple births and fertility rates of women of 35 years and over. The variables were highly correlated to which other over time. In 2000, 8.2% of all pregnancies resulted in preterm births (0.9% in fetal deaths and 7.3% in live births). In 2010, the preterm birth increased to 9.4% (0.8% were preterm fetal deaths and 8.6% preterm live births). The results suggest that 45.2% could be the maximum contribution of successful interventions to prevent a fetal death on the increase in preterm live births. This increasing trend is also related to changes of the women reproductive profile with the change of the women reproductive profile and access to prenatal care.

Characteristics and risk factors of preterm births in a tertiary center in Lagos, Nigeria.

PubMed

Butali, Azeez; Ezeaka, Chinyere; Ekhaguere, Osayame; Weathers, Nancy; Ladd, Jenna; Fajolu, Iretiola; Esezobor, Christopher; Makwe, Christian; Odusanya, Bukola; Anorlu, Rose; Adeyemo, Wasiu; Iroha, Edna; Egri-Okwaji, Mathias; Adejumo, Prisca; Oyeneyin, Lawal; Abiodun, Moses; Badejoko, Bolaji; Ryckman, Kelli

2016-01-01

Preterm birth is a dire complication of pregnancy that poses huge long-term medical and financial burdens for affected children, their families, and the health care system. The aim of the present study was to identify characteristics associated with preterm births at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria from 2011 to 2013. We obtained Information from 5,561 maternal, fetal/neonatal and obstetric records from the labor ward. We excluded delivery at less than 22 weeks (0.25%), post-term birth at ≥42 weeks gestation (1.3%), and unknown gestation (1.4%). Additionally, we excluded records of multiple births (5.4%) and stillbirths (8.3%) leaving 4,691 records of singleton live-births for analysis. Logistic regression analysis was performed comparing preterm birth (22-36 weeks gestation) to term birth (37-41 weeks gestation). Multiple variable models adjusting for maternal age, parity, fetal position, delivery method and booking status were also evaluated. Multinomial regression was used to identify characteristics associated with preterm birth (PTB) defined as early PTB (22-31 weeks gestation), moderate PTB (32-34 weeks gestation), late PTB (35-36 weeks gestation), compared to term birth (37-41 completed weeks gestation). From our data, 16.8% of the singleton live-birth deliveries were preterm (<37 weeks gestation). Of these, 4.7% were early (22-31 weeks), 4.5% were moderate (32-34 weeks) and 7.7% were late (35-36) PTBs. Older maternal age (≥35 years) [odds ratio (OR) = 1.41], hypertension (OR = 3.44) and rupture of membranes (OR = 4.03) were significantly associated with increased odds of PTB. Women being treated for the prevention of mother-to-child transmission of HIV were at a significantly decreased risk for PTB (OR = 0.70). Sixteen percent of women in this cohort were not registered for antenatal care in LUTH. These non-registered subjects had significantly greater odds of all categories of PTB, including early (odds ratio (OR) = 20.8), moderate (OR = 8.68), and late (OR = 2.15). PTB and risks for PTB remain high in Nigeria. We recommend that any high risk pregnancy should be referred to a tertiary center for prenatal care in order to significantly reduce adverse birth outcomes such as PTBs.

Characteristics and risk factors of preterm births in a tertiary center in Lagos, Nigeria

PubMed Central

Butali, Azeez; Ezeaka, Chinyere; Ekhaguere, Osayame; Weathers, Nancy; Ladd, Jenna; Fajolu, Iretiola; Esezobor, Christopher; Makwe, Christian; Odusanya, Bukola; Anorlu, Rose; Adeyemo, Wasiu; Iroha, Edna; Egri-Okwaji, Mathias; Adejumo, Prisca; Oyeneyin, Lawal; Abiodun, Moses; Badejoko, Bolaji; Ryckman, Kelli

2016-01-01

Introduction Preterm birth is a dire complication of pregnancy that poses huge long-term medical and financial burdens for affected children, their families, and the health care system. The aim of the present study was to identify characteristics associated with preterm births at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria from 2011 to 2013. Methods We obtained Information from 5,561 maternal, fetal/neonatal and obstetric records from the labor ward. We excluded delivery at less than 22 weeks (0.25%), post-term birth at ≥42 weeks gestation (1.3%), and unknown gestation (1.4%). Additionally, we excluded records of multiple births (5.4%) and stillbirths (8.3%) leaving 4,691 records of singleton live-births for analysis. Logistic regression analysis was performed comparing preterm birth (22-36 weeks gestation) to term birth (37-41 weeks gestation). Multiple variable models adjusting for maternal age, parity, fetal position, delivery method and booking status were also evaluated. Multinomial regression was used to identify characteristics associated with preterm birth (PTB) defined as early PTB (22-31 weeks gestation), moderate PTB (32-34 weeks gestation), late PTB (35-36 weeks gestation), compared to term birth (37-41 completed weeks gestation). Results From our data, 16.8% of the singleton live-birth deliveries were preterm (<37 weeks gestation). Of these, 4.7% were early (22-31 weeks), 4.5% were moderate (32-34 weeks) and 7.7% were late (35-36) PTBs. Older maternal age (≥35 years) [odds ratio (OR) = 1.41], hypertension (OR = 3.44) and rupture of membranes (OR = 4.03) were significantly associated with increased odds of PTB. Women being treated for the prevention of mother-to-child transmission of HIV were at a significantly decreased risk for PTB (OR = 0.70). Sixteen percent of women in this cohort were not registered for antenatal care in LUTH. These non-registered subjects had significantly greater odds of all categories of PTB, including early (odds ratio (OR) = 20.8), moderate (OR = 8.68), and late (OR = 2.15). Conclusion PTB and risks for PTB remain high in Nigeria. We recommend that any high risk pregnancy should be referred to a tertiary center for prenatal care in order to significantly reduce adverse birth outcomes such as PTBs. PMID:27583065

Metropolitan isolation segregation and Black-White disparities in very preterm birth: a test of mediating pathways and variance explained.

PubMed

Kramer, Michael R; Cooper, Hannah L; Drews-Botsch, Carolyn D; Waller, Lance A; Hogue, Carol R

2010-12-01

Residential isolation segregation (a measure of residential inter-racial exposure) has been associated with rates of preterm birth (<37 weeks gestation) experienced by Black women. Epidemiologic differences between very preterm (<32 weeks gestation) and moderately preterm births (32-36 weeks) raise questions about whether this association is similar across gestational ages, and through what pathways it might be mediated. Hierarchical Bayesian models were fit to answer three questions: is the isolation-prematurity association similar for very and moderately preterm birth; is this association mediated by maternal chronic disease, socioeconomic status, or metropolitan area crime and poverty rates; and how much of the geographic variation in Black-White very preterm birth disparities is explained by isolation segregation? Singleton births to Black and White women in 231 U.S. metropolitan statistical areas in 2000-2002 were analyzed and isolation segregation was calculated for each. We found that among Black women, isolation is associated with very preterm birth and moderately preterm birth. The association may be partially mediated by individual level socioeconomic characteristics and metropolitan level violent crime rates. There is no association between segregation and prematurity among White women. Isolation segregation explains 28% of the geographic variation in Black-White very preterm birth disparities. Our findings highlight the importance of isolation segregation for the high-burden outcome of very preterm birth, but unexplained excess risk for prematurity among Black women is substantial. Copyright © 2010 Elsevier Ltd. All rights reserved.

Combination antiretroviral use and preterm birth.

PubMed

Watts, D Heather; Williams, Paige L; Kacanek, Deborah; Griner, Raymond; Rich, Kenneth; Hazra, Rohan; Mofenson, Lynne M; Mendez, Hermann A

2013-02-15

Use of antiretroviral drugs (ARVs) during pregnancy has been associated with higher risk of preterm birth. The Pediatric HIV/AIDS Cohort Study network's Surveillance Monitoring for ART Toxicities study is a US-based cohort of human immunodeficiency virus (HIV)-exposed uninfected children. We evaluated maternal ARV use during pregnancy and the risk of any type of preterm birth (ie, birth before 37 completed weeks of gestation), the risk of spontaneous preterm birth (ie, preterm birth that occurred after preterm labor or membrane rupture, without other complications), and the risk of small for gestational age (SGA; ie, a birth weight of <10th percentile for gestational age). Multivariable logistic regression models were used to evaluate the association of ARVs and timing of exposure, while adjusting for maternal characteristics. Among 1869 singleton births, 18.6% were preterm, 10.2% were spontaneous preterm, and 7.3% were SGA. A total of 89% used 3-drug combination ARV regimens during pregnancy. In adjusted models, the odds of preterm birth and spontaneous preterm birth were significantly greater among mothers who used protease inhibitors during the first trimester (adjusted odds ratios, 1.55 and 1.59, respectively) but not among mothers who used nonnucleoside reverse-transcriptase inhibitor or triple-nucleoside regimens during the first trimester. Combination ARV exposure starting later in pregnancy was not associated with increased risk. No associations were observed between SGA and exposure to combination ARV regimens. Protease inhibitor use early in pregnancy may be associated with increased risk for prematurity.

Psychosocial Stress and Preterm Birth: The Impact of Parity and Race.

PubMed

Wheeler, Sarahn; Maxson, Pamela; Truong, Tracy; Swamy, Geeta

2018-03-29

Objectives Studies examining risk factors for preterm birth (PTB) such as psychosocial stress are often focused on women with a history of PTB; however, most preterm babies are born to women with no history of preterm birth. Our objective was to determine if the relationship between psychosocial stress and PTB is altered by parity. Non-Hispanic black (NHB) women have increased psychosocial stress and PTB; therefore, we further aimed to determine if race alters the relationship between psychosocial stress, parity, and PTB. Methods We performed a secondary analysis of the Healthy Pregnancy, Healthy Baby Study comparing pregnant women who were primiparous (first pregnancy), multiparous with history of preterm birth, or multiparous with history of term birth. Perceived stress, perceived racism, interpersonal support, John Henryism and self-efficacy were measured using validated instruments. Logistic regression was used to model the effect of psychosocial stress on PTB stratified by parity and race. Results The analysis entire cohort included 1606 subjects, 426 were primiparous, 268 had a history of presterm birth, and 912 had a history of term birth. In women with a history of term birth, higher self-efficacy was associated with lower odds of spontaneous PTB, and this association was amplified in NHB women. In women with a history of spontaneous PTB, John Henryism Active Coping was associated with lower odds of spontaneous PTB in the index pregnancy. Conclusions for Practice The relationship between psychosocial stress and PTB may be mediated by parity and race.

Factors for Preterm Births in Germany - An Analysis of Representative German Data (KiGGS).

PubMed

Weichert, A; Weichert, T M; Bergmann, R L; Henrich, W; Kalache, K D; Richter, R; Neymeyer, J; Bergmann, K E

2015-08-01

Introduction: Preterm birth is a global scourge, the leading cause of perinatal mortality and morbidity. This study set out to identify the principal risk factors for preterm birth, based on the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). A range of possible factors influencing preterm birth were selected for inclusion in the questionnaire, covering factors such as gender, national origin, immigrant background, demography, living standard, family structure, parental education and vocational training. Methods: All data were taken from the aforementioned KiGGS survey conducted between 2003 and 2006. A total of 17 641 children and adolescents (8656 girls and 8985 boys) drawn from 167 German towns and municipalities deemed to be representative of the Federal Republic of Germany were included in the study. Gestational age at birth was available for 14 234 datasets. The questionnaire included questions from the following areas as possible factors influencing preterm birth: gender, national origins, immigrant background, demography, living standard, family structure, parental education and vocational training. Results: The preterm birth rate was 11.6 %, higher than that of other national statistical evaluations. Around 57.4 % of multiple pregnancies and 10 % of singleton pregnancies resulted in preterm delivery. Multiple pregnancy was found to be the most important risk factor (OR 13.116). With regard to national origins and immigration background, mothers from Turkey, the Middle East, and North Africa had a higher incidence of preterm birth. Preterm birth was more prevalent in cities and large towns than in small towns and villages. Conclusion: Risk factors associated with preterm birth were identified. These should help with the early identification of pregnant women at risk. The preterm birth rate in our survey was higher than that found in other national statistical evaluations based on process data. More than half of all multiple pregnancies ended in preterm birth.

Comparing exposure assessment methods for traffic-related air pollution in an adverse pregnancy outcome study

PubMed Central

Wu, Jun; Wilhelm, Michelle; Chung, Judith; Ritz, Beate

2011-01-01

Background Previous studies reported adverse impacts of traffic-related air pollution exposure on pregnancy outcomes. Yet, little information exists on how effect estimates are impacted by the different exposure assessment methods employed in these studies. Objectives To compare effect estimates for traffic-related air pollution exposure and preeclampsia, preterm birth (gestational age less than 37 weeks), and very preterm birth (gestational age less than 30 weeks) based on four commonly-used exposure assessment methods. Methods We identified 81,186 singleton births during 1997–2006 at four hospitals in Los Angeles and Orange Counties, California. Exposures were assigned to individual subjects based on residential address at delivery using the nearest ambient monitoring station data [carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NO), nitrogen oxides (NOx), ozone (O3), and particulate matter less than 2.5 (PM2.5) or less than 10 (PM10) μm in aerodynamic diameter], both unadjusted and temporally-adjusted land-use regression (LUR) model estimates (NO, NO2, and NOx), CALINE4 line-source air dispersion model estimates (NOx and PM2.5), and a simple traffic-density measure. We employed unconditional logistic regression to analyze preeclampsia in our birth cohort, while for gestational age-matched risk sets with preterm and very preterm birth we employed conditional logistic regression. Results We observed elevated risks for preeclampsia, preterm birth, and very preterm birth from maternal exposures to traffic air pollutants measured at ambient stations (CO, NO, NO2, and NOx) and modeled through CALINE4 (NOx and PM2.5) and LUR (NO2 and NOx). Increased risk of preterm birth and very preterm birth were also positively associated with PM10 and PM2.5 air pollution measured at ambient stations. For LUR-modeled NO2 and NOx exposures, elevated risks for all the outcomes were observed in Los Angeles only – the region for which the LUR models were initially developed. Unadjusted LUR models often produced odds ratios somewhat larger in size than temporally-adjusted models. The size of effect estimates was smaller for exposures based on simpler traffic density measures than the other exposure assessment methods. Conclusion We generally confirmed that traffic-related air pollution was associated with adverse reproductive outcomes regardless of the exposure assessment method employed, yet the size of the estimated effect depended on how both temporal and spatial variations were incorporated into exposure assessment. The LUR model was not transferable even between two contiguous areas within the same large metropolitan area in Southern California. PMID:21453913

Associations of maternal pre-pregnancy underweight with small-for-gestational-age and spontaneous preterm birth, and optimal gestational weight gain in Japanese women.

PubMed

Fujiwara, Kana; Aoki, Shigeru; Kurasawa, Kentaro; Okuda, Mika; Takahashi, Tsuneo; Hirahara, Fumiki

2014-04-01

To determine associations of maternal pre-pregnancy underweight with poor outcomes and evaluate how gestational weight gain affects risks for such outcomes in pre-pregnancy underweight Japanese women. By analyzing the January 2001-December 2012 hospital database, we retrospectively identified 6954 women with pre-pregnancy normal weights (body mass index, 18.5-24.9 kg/m²) and 1057 pre-pregnancy underweight women (body mass index, <18.5 kg/m²) who delivered at the Perinatal Maternity and Neonatal Center of Yokohama City University. These women were stratified by weekly weight gain during the second/third trimesters to investigate associations of gestational weight gain with spontaneous preterm birth and small for gestational age (SGA). Spontaneous preterm birth and SGA incidences were compared with those of women meeting Institute of Medicine (IO M) guidelines to determine optimal weight gain in Japanese women. Preterm birth and SGA incidences were significantly higher in pre-pregnancy underweight than in pre-pregnancy normal weight women (4.6% vs 2.4% [P=0.005] and 13.9% vs 9.7% [P = 0.003], respectively). For pre-pregnancy normal weight women, preterm birth incidence was significantly higher in those with weight gain of less than 0.2 kg/week than in those IOM guidelines. For pre-pregnancy underweight women, preterm birth and SGA incidences were significantly higher in those with weight gain of less than 0.3 kg/week than in those meeting IOM guidelines. Preterm birth and SGA incidences did not differ significantly between pre-pregnancy normal weight women with weight gain of 0.2 kg/week or more and pre-pregnancy underweight women with weight gain of 0.3 kg/week or more, as compared to women meeting IOM guidelines. These results suggest that IOM guidelines for gestational weight gain may lack external validity in Japanese women. © 2014 The Authors. Journal of Obstetrics and Gynaecology Research © 2014 Japan Society of Obstetrics and Gynecology.

Pain sensitivity and temperament in extremely low-birth-weight premature toddlers and preterm and full-term controls.

PubMed

Grunau, R V; Whitfield, M F; Petrie, J H

1994-09-01

High-technology medical care of extremely low-birth-weight (ELBW) infants (< 1001 g) involves repeated medical interventions which are potentially painful and may later affect reaction to pain. At 18 months corrected age (CCA), we examined parent ratings of pain sensitivity and how pain sensitivity ratings related to child temperament and parenting style in 2 groups of ELBW children (49 with a birth weight of 480-800 g and 75 with a birth weight of 801-1000 g) and 2 control groups (42 heavier preterm (1500-2499 g) and 29 full-birth-weight (FBW) children (> 2500 g). Both groups of ELBW toddlers were rated by parents as significantly lower in pain sensitivity compared with both control groups. The relationships between child temperament and pain sensitivity rating varied systematically across the groups. Temperament was strongly related to rated pain sensitivity in the FBW group, moderately related in the heavier preterm and ELBW 801-1000 g groups, and not related in the lowest birth-weight group (< 801 g). Parental style did not mediate ratings of pain sensitivity. The results suggest that parents perceive differences in pain behavior of ELBW toddlers compared with heavier preterm and FBW toddlers, especially for those less than 801 g. Longitudinal research into the development of pain behavior for infants who experience lengthy hospitalization is warranted.

Exploration of preterm birth rates associated with different models of antenatal midwifery care in Scotland: Unmatched retrospective cohort analysis.

PubMed

Symon, Andrew; Winter, Clare; Cochrane, Lynda

2015-06-01

preterm birth represents a significant personal, clinical, organisational and financial burden. Strategies to reduce the preterm birth rate have had limited success. Limited evidence indicates that certain antenatal care models may offer some protection, although the causal mechanism is not understood. We sought to compare preterm birth rates for mixed-risk pregnant women accessing antenatal care organised at a freestanding midwifery unit (FMU) and mixed-risk pregnant women attending an obstetric unit (OU) with related community-based antenatal care. unmatched retrospective 4-year Scottish cohort analysis (2008-2011) of mixed-risk pregnant women accessing (i) FMU antenatal care (n=1107); (ii) combined community-based and OU antenatal care (n=7567). Data were accessed via the Information and Statistics Division of the NHS in Scotland. Aggregates analysis and binary logistic regression were used to compare the cohorts׳ rates of preterm birth; and of spontaneous labour onset, use of pharmacological analgesia, unassisted vertex birth, and low birth weight. Odds ratios were adjusted for age, parity, deprivation score and smoking status in pregnancy. after adjustment the 'mixed risk' FMU cohort had a statistically significantly reduced risk of preterm birth (5.1% [n=57] versus 7.7% [n=583]; AOR 0.73 [95% CI 0.55-0.98]; p=0.034). Differences in these secondary outcome measures were also statistically significant: spontaneous labour onset (FMU 83.9% versus OU 74.6%; AOR 1.74 [95% CI 1.46-2.08]; p<0.001); minimal intrapartum analgesia (FMU 53.7% versus OU 34.4%; AOR 2.17 [95% CI 1.90-2.49]; p<0.001); spontaneous vertex delivery (FMU 71.9% versus OU 63.5%; AOR 1.46 [95% CI 1.32-1.78]; p<0.001). Incidence of low birth weight was not statistically significant after adjustment for other variables. There was no significant difference in the rate of perinatal or neonatal death. given this study׳s methodological limitations, we can only claim associations between the care model and or chosen outcomes. Although both cohorts were mixed risk, differences in risk levels could have contributed to these findings. Nevertheless, the significant difference in preterm birth rates in this study resonates with other research, including the recent Cochrane review of midwife-led continuity models. Because of the multiplicity of risk factors for preterm birth we need to explore the salient features of the FMU model which may be contributing to this apparent protective effect. Because a randomised controlled trial would necessarily restrict choice to pregnant women, we feel that this option is problematic in exploring this further. We therefore plan to conduct a prospective matched cohort analysis together with a survey of unit practices and experiences. Copyright © 2015 Elsevier Ltd. All rights reserved.

Motor development curve from 0 to 12 months in infants born preterm.

PubMed

Kayenne Martins Roberto Formiga, Cibelle; Linhares, Maria Beatriz Martins

2011-03-01

To trace a reference curve for motor development from birth up to 12 months of corrected chronological age in infants born preterm and low birth weight. This is a cross-sectional study with a sample of 308 preterm infants (53% boys) weighing < 2500 g at birth. The Alberta Infant Motor Scale (AIMS) was used for motor development assessment. Comparing the motor performance of preterm infants with infants from a standardized sample on the AIMS, it was found that, except for the age group of the newborn, preterm infants showed lower motor development scores in comparison with the AIMS normative sample in all age groups between 1 and 12 months. The curve of motor development showed a continuous increase in the number of motor skills of preterm infants during their first 12 months of age. However, the average of motor acquisitions of preterm infants showed a nonlinear pattern with a standard indicator of stabilization between 8 and 10 months of age. Preterm infants, 1-12 months of age, showed motor development AIMS scores lower than the standards established in the normative sample. The findings may contribute as norm-reference for assessing the motor development of preterm infants in follow-up programmes in developing countries. © 2010 The Author(s)/Acta Paediatrica © 2010 Foundation Acta Paediatrica.

Risk of preterm birth by subtype among Medi-Cal participants with mental illness.

PubMed

Baer, Rebecca J; Chambers, Christina D; Bandoli, Gretchen; Jelliffe-Pawlowski, Laura L

2016-10-01

Previous studies have demonstrated an association between mental illness and preterm birth (before 37 weeks). However, these investigations have not simultaneously considered gestation of preterm birth, the indication (eg, spontaneous or medically indicated), and specific mental illness classifications. The objective of the study was to examine the likelihood of preterm birth across gestational lengths and indications among Medi-Cal (California's Medicaid program) participants with a diagnostic code for mental illness. Mental illnesses were studied by specific illness classification. The study population was drawn from singleton live births in California from 2007 through 2011 in the birth cohort file maintained by the California Office of Statewide Health Planning and Development, which includes birth certificate and hospital discharge records. The sample was restricted to women with Medi-Cal coverage for prenatal care. Women with mental illness were identified using International Classification of Diseases, ninth revision, codes from their hospital discharge record. Women without a mental illness International Classification of Diseases, ninth revision, code were randomly selected at a 4:1 ratio. Adjusting for maternal characteristics and obstetric complications, relative risks and 95% confidence intervals were calculated for preterm birth comparing women with a mental illness diagnostic code with women without such a code. We identified 6198 women with a mental illness diagnostic code and selected 24,792 women with no such code. The risk of preterm birth in women with a mental illness were 1.2 times higher than women without a mental illness (adjusted relative risk, 1.2, 95% confidence interval, 1.1-1.3). Among the specific mental illnesses, schizophrenia, major depression, and personality disorders had the strongest associations with preterm birth (adjusted relative risks, 2.0, 2.0 and 3.3, respectively). Women receiving prenatal care through California's low-income health insurance who had at least 1 mental illness diagnostic code were 1.2-3.3-times more likely to have a preterm birth than women without a mental illness, and these risks persisted across most illness classifications. Although it cannot be determined from these data whether specific treatments for mental illness contribute to the observed associations, elevated risk across different diagnoses suggests that some aspects of mental illness itself may confer risk. Copyright © 2016 Elsevier Inc. All rights reserved.

Preterm Birth in the Context of Increasing Income Inequality.

PubMed

Wallace, Maeve E; Mendola, Pauline; Chen, Zhen; Hwang, Beom Seuk; Grantz, Katherine L

2016-01-01

Preterm birth is a leading cause of infant morbidity and mortality. Little is known about the contextual effect of U.S. income inequality on preterm birth, an issue of increasing concern given that the current economic divide is the largest since 1928. We examined changes in inequality over time in relation to preterm birth among singleton deliveries from an electronic medical record-based cohort (n = 223,512) conducted in 11 U.S. states and the District of Columbia from 2002 to 2008. Increasing income inequality was defined as a positive change in state-level Gini coefficient from the year prior to birth. Multi-level models estimated the independent effect of increasing inequality on preterm birth (>22 and <37 weeks) controlling for maternal demographics, health behaviors, insurance status, chronic medical conditions, and state-level poverty and unemployment during the year of birth. The preterm birth rate was 12.3% where inequality increased and 10.9% where it did not. After adjustment, increasing inequality remained significantly associated with preterm birth (adjusted odds ratio 1.07, 95% confidence interval 1.04, 1.11). We observed no significant interaction by insurance status or race, suggesting that increasing inequality had a broad effect across the population. The contextual effect of increasing income inequality on preterm birth risk merits further study.

Perinatal health services organization for preterm births: a multinational comparison.

PubMed

Kelly, L E; Shah, P S; Håkansson, S; Kusuda, S; Adams, M; Lee, S K; Sjörs, G; Vento, M; Rusconi, F; Lehtonen, L; Reichman, B; Darlow, B A; Lui, K; Feliciano, L S; Gagliardi, L; Bassler, D; Modi, N

2017-07-01

To explore population characteristics, organization of health services and comparability of available information for very low birth weight or very preterm neonates born before 32 weeks' gestation in 11 high-income countries contributing data to the International Network for Evaluating Outcomes of Neonates (iNeo). We obtained population characteristics from public domain sources, conducted a survey of organization of maternal and neonatal health services and evaluated the comparability of data contributed to the iNeo collaboration from Australia, Canada, Finland, Israel, Italy, Japan, New Zealand, Spain, Sweden, Switzerland and UK. All countries have nationally funded maternal/neonatal health care with >90% of women receiving prenatal care. Preterm birth rate, maternal age, and neonatal and infant mortality rates were relatively similar across countries. Most (50 to >95%) between-hospital transports of neonates born at non-tertiary units were conducted by designated transport teams; 72% (8/11 countries) had designated transfer and 63% (7/11 countries) mandate the presence of a physician. The capacity of 'step-down' units varied between countries, with capacity for respiratory care available in <10% to >75% of units. Heterogeneity in data collection processes for benchmarking and quality improvement activities were identified. Comparability of healthcare outcomes for very preterm low birth weight neonates between countries requires an evaluation of differences in population coverage, healthcare services and meta-data.

Use of Continuous Electronic Fetal Monitoring in a Preterm Fetus: Clinical Dilemmas and Recommendations for Practice

PubMed Central

Afors, Karolina; Chandraharan, Edwin

2011-01-01

The aim of intrapartum continuous electronic fetal monitoring using a cardiotocograph (CTG) is to identify a fetus exposed to intrapartum hypoxic insults so that timely and appropriate action could be instituted to improve perinatal outcome. Features observed on a CTG trace reflect the functioning of somatic and autonomic nervous systems and the fetal response to hypoxic or mechanical insults during labour. Although, National Guidelines on electronic fetal monitoring exist for term fetuses, there is paucity of recommendations based on scientific evidence for monitoring preterm fetuses during labour. Lack of evidence-based recommendations may pose a clinical dilemma as preterm births account for nearly 8% (1 in 13) live births in England and Wales. 93% of these preterm births occur after 28 weeks, 6% between 22–27 weeks, and 1% before 22 weeks. Physiological control of fetal heart rate and the resultant features observed on the CTG trace differs in the preterm fetus as compared to a fetus at term making interpretation difficult. This review describes the features of normal fetal heart rate patterns at different gestations and the physiological responses of a preterm fetus compared to a fetus at term. We have proposed an algorithm “ACUTE” to aid management. PMID:21922045

Temporal Trends in Late Preterm and Early Term Birth Rates in 6 High-Income Countries in North America and Europe and Association With Clinician-Initiated Obstetric Interventions

PubMed Central

Richards, Jennifer L.; Kramer, Michael S.; Deb-Rinker, Paromita; Rouleau, Jocelyn; Mortensen, Laust; Gissler, Mika; Morken, Nils-Halvdan; Skjærven, Rolv; Cnattingius, Sven; Johansson, Stefan; Delnord, Marie; Dolan, Siobhan M.; Morisaki, Naho; Tough, Suzanne; Zeitlin, Jennifer; Kramer, Michael R.

2017-01-01

IMPORTANCE Clinicians have been urged to delay the use of obstetric interventions (eg, labor induction, cesarean delivery) until 39 weeks or later in the absence of maternal or fetal indications for intervention. OBJECTIVE To describe recent trends in late preterm and early term birth rates in 6 high-income countries and assess association with use of clinician-initiated obstetric interventions. DESIGN Retrospective analysis of singleton live births from 2006 to the latest available year (ranging from 2010 to 2015) in Canada, Denmark, Finland, Norway, Sweden, and the United States. EXPOSURES Use of clinician-initiated obstetric intervention (either labor induction or prelabor cesarean delivery) during delivery. MAIN OUTCOMES AND MEASURES Annual country-specific late preterm (34–36 weeks) and early term (37–38 weeks) birth rates. RESULTS The study population included 2 415 432 Canadian births in 2006–2014 (4.8% late preterm; 25.3% early term); 305 947 Danish births in 2006–2010 (3.6% late preterm; 18.8% early term); 571 937 Finnish births in 2006–2015 (3.3% late preterm; 16.8% early term); 468 954 Norwegian births in 2006–2013 (3.8% late preterm; 17.2% early term); 737 754 Swedish births in 2006–2012 (3.6% late preterm; 18.7% early term); and 25 788 558 US births in 2006–2014 (6.0% late preterm; 26.9% early term). Late preterm birth rates decreased in Norway (3.9% to 3.5%) and the United States (6.8% to 5.7%). Early term birth rates decreased in Norway (17.6% to 16.8%), Sweden (19.4% to 18.5%), and the United States (30.2% to 24.4%). In the United States, early term birth rates decreased from 33.0% in 2006 to 21.1% in 2014 among births with clinician-initiated obstetric intervention, and from 29.7% in 2006 to 27.1% in 2014 among births without clinician-initiated obstetric intervention. Rates of clinician-initiated obstetric intervention increased among late preterm births in Canada (28.0% to 37.9%), Denmark (22.2% to 25.0%), and Finland (25.1% to 38.5%), and among early term births in Denmark (38.4% to 43.8%) and Finland (29.8% to 40.1%). CONCLUSIONS AND RELEVANCE Between 2006 and 2014, late preterm and early term birth rates decreased in the United States, and an association was observed between early term birth rates and decreasing clinician-initiated obstetric interventions. Late preterm births also decreased in Norway, and early term births decreased in Norway and Sweden. Clinician-initiated obstetric interventions increased in some countries but no association was found with rates of late preterm or early term birth. PMID:27458946

The maternal and neonatal outcomes for an urban Indigenous population compared with their non-Indigenous counterparts and a trend analysis over four triennia.

PubMed

Kildea, Sue; Stapleton, Helen; Murphy, Rebecca; Kosiak, Machellee; Gibbons, Kristen

2013-08-30

Indigenous Australians experience significantly disproportionate poorer health outcomes compared to their non-Indigenous counterparts. Despite the recognised importance of maternal infant health (MIH), there is surprisingly little empirical research to guide service redesign that successfully addresses the disparities. This paper reports on a service evaluation that also compared key MIH indicators for Indigenous and non-Indigenous mothers and babies over a 12-year period 1998-2009. Trend analysis with logistic regression, using the independent variables of ethnicity and triennia, explored changes over time (1998-2009) between two cohorts: 1,523 births to Indigenous mothers and 43,693 births to non-Indigenous mothers. We included bivariate and multivariate analysis on key indicators (e.g. teenage births, preterm birth, low birth weight, smoking) and report odds ratios (ORs), 95% CIs and logistic regression adjusting for important confounders. We excluded transfers in from other areas which are identified within the database. Bivariate analysis revealed Indigenous women were statistically more likely to have spontaneous onset of labour and a non-instrumental vaginal birth. They were less likely to take epidurals for pain relief in labour, have assisted births, caesarean sections or perineal trauma. Despite better labour outcomes, Indigenous babies were more likely to be born preterm (< 37 weeks) and be low birth weight (< 2500 g); these differences remained significant in multivariate analysis. The trend analysis revealed relatively stable rates for teenage pregnancy, small for gestational age, low birth weight babies, and perinatal mortality for both cohorts, with the gap between cohorts consistent over time. A statistical widening of the gap in preterm birth and smoking rates was found with preterm birth demonstrating a relative increase of 51% over this period. The comprehensive database from a large urban hospital allowed a thorough examination of outcomes and contributing factors. The gap between both cohorts remains static in several areas but in some cases worsened. Alternative models for delivering care to Indigenous women and their babies have shown improved outcomes, including preterm birth, though not all have been sustained over time and none are available Australia-wide. New models of care, which recognise the heterogeneity of Indigenous communities, incorporate a multiagency approach, and are set within a research framework, are urgently needed.

Serum zinc levels of cord blood: relation to birth weight and gestational period.

PubMed

Gómez, Tahiry; Bequer, Leticia; Mollineda, Angel; González, Olga; Diaz, Mireisy; Fernández, Douglas

2015-04-01

Zn-deficiency has been associated with numerous alterations during pregnancy including low birth weight; however, the research relating neonatal zinc status and birth weight has not produced reliable results. To compare the serum Zn-levels of cord blood in healthy newborns and low birth weight newborns, and to assess a possible relationship between zinc concentration and neonatal birth weight and gestational age. 123 newborns divided in "study group" (n=50) with <2500g birth weight neonates and "control group" (n=73) with ≥2500g birth weight neonates were enrolled. Study group was subdivided according to gestational age in preterm (<37 weeks) and full-term (≥37 weeks). Serum cord blood samples were collected and the Zn-levels were analyzed using flame Atomic Absorption Spectrophotometry method and the result was expressed in μmol/L. The Zn-levels were compared between the groups (Mann-Whitney-U test) and the Zn-levels were correlated with the birth weight and gestational age (Spearman's rank correlations). Statistically significant low positive correlation between Zn-levels and birth weight (ρ=0.283; p=0.005) was found. No statistically significant difference between Zn-levels of study and control groups [17.00±0.43 vs. 18.16±0.32 (p=0.053)] was found. Statistically significant low positive correlation between Zn-levels and gestational age (ρ=0.351; p=0.001) was found. No statistically significant difference between Zn-levels of preterm as compare to full-term newborns [16.33±0.42 vs. 18.43±0.93 (p=0.079)] was found. Zn-level of preterm subgroup was significantly lower compared to control group (p=0.001). Despite low birth weight preterm neonates had significantly lower serum zinc levels of cord blood than healthy term neonates, the correlation between cord blood zinc levels and birth weight and gestational age was lower. The results are not enough to relate the change in cord blood zinc concentration to the birth weight values or gestational period. In relation to complicated pregnancies, further studies regarding zinc levels in blood in our population are required. Copyright © 2015 Elsevier GmbH. All rights reserved.

BCG vaccination reaction in low birth weight infants.

PubMed

Kaur, S; Faridi, M M A; Agarwal, K N

2002-08-01

About 30 per cent newborns (preterm and term) weigh < 2500 g at birth. The immunological system is less mature in low birth weight (LBW) babies compared to term and normal birth weight (NBW) babies. Bacille Calmettee Guerin (BCG) vaccine is given at birth under the national immunization programme. There is a paucity of information on the immunogenicity of BCG vaccine in preterm and LBW babies. It was, therefore, proposed to study the reaction of BCG vaccination in LBW, preterm and normal birth weight newborns. A total of 143 newborns (90 term and 53 preterm; of these 78 were LBW) received during March to September 1998, 0.1 ml of BCG vaccine (Danish 1331 strain) intradermally on the left arm just above the insertion of the deltoid muscle within 7 days of life. At the same time trivalent oral polio vaccine was administered as per the national immunization programme. These babies were followed up in the immunization clinic at 4, 6, 8, 10 and 12 +/- 1 wk to observe reactions at the BCG vaccination site. After 4 wk reaction at the vaccination site was significantly (P < 0.001) delayed in preterm babies as compared to term infants, and in the LBW babies (P < 0.05) as compared to NBW babies. The reaction at the site of vaccination was not found to be different at 6, 8, 10, 12 wk. BCG scar was seen in 47.5 per cent infants (45.4% in < 2500 g birth weight and 50% in > or = 2500 g birth weight infants) at 12 wk. But 33 (42.3%) LBW and 24 (36.9%) NBW infants also showed papule, pustule, ulceration or scab at the BCG vaccination site. The BCG reaction was seen in the sequential order from papule to scar formation. No significant difference was seen in the scar formation in infants studied with varying gestation and birth weights after 12 wk of BCG vaccination. Fifty seven (40.4%) babies still showed different stages of BCG reaction at 12 wk. BCG vaccine along with OPV administered in early neonatal life showed successful BCG reaction in 95.5 per cent infants.

Birth outcomes following immunization of pregnant women with pandemic H1N1 influenza vaccine 2009-2010.

PubMed

Eaton, Abigail; Lewis, Ned; Fireman, Bruce; Hansen, John; Baxter, Roger; Gee, Julianne; Klein, Nicola P

2018-05-03

Following the H1N1 influenza pandemic in 2009, pregnant women were recommended to receive both seasonal (TIV) and H1N1 influenza vaccines. This study presents incidence of adverse birth and pregnancy outcomes among a population of pregnant women immunized with TIV and H1N1 vaccines at Kaiser Permanente Northern California during 2009-2010. We telephone surveyed pregnant Kaiser Permanente Northern California members to assess non-medically-attended reactions following H1N1, TIV or both vaccines during 2009-2010 (n=5365) in a separate study. Here we assessed preterm birth (<37weeks), very preterm birth (<32weeks), low birth weight (<2500 g, LBW), very low birth weight (<1500g), small for gestational age, spontaneous abortions, stillbirths and congenital anomalies among this cohort by comparing incidence and 95% confidence intervals between the following immunization groups: TIV only, H1N1 only, H1N1 prior to TIV immunization, TIV prior to H1N1 and both immunizations given at the same time. Results did not vary significantly between groups. Comparing H1N1 with TIV, incidence were similar for preterm births (6.37vs 6.28/100 births), very preterm births (5.30vs 8.29/1000 births), LBW (4.19vs 2.90/100 births), very LBW (4.54vs 5.52/1000 births), small for gestational age (9.99vs 9.24/1000 births), spontaneous abortion (7.10vs 6.83/1000 pregnancies), stillbirths (7.10vs 4.57/1000 pregnancies), and congenital anomalies (2.66vs 2.43/100 births). Although constrained by small sample size, complex vaccine groups, and differential vaccine availability during 2009-2010, this study found no difference in adverse birth outcomes between H1N1 vaccine and TIV. Copyright © 2017 Elsevier Ltd. All rights reserved.

Low birth weight in the United States.

PubMed

Goldenberg, Robert L; Culhane, Jennifer F

2007-02-01

Pregnancy outcomes in the United States and other developed countries are considerably better than those in many developing countries. However, adverse pregnancy outcomes are generally more common in the United States than in other developed countries. Low-birth-weight infants, born after a preterm birth or secondary to intrauterine growth restriction, account for much of the increased morbidity, mortality, and cost. Wide disparities exist in both preterm birth and growth restriction among different population groups. Poor and black women, for example, have twice the preterm birth rate and higher rates of growth restriction than do most other women. Low birth weight in general is thought to place the infant at greater risk of later adult chronic medical conditions, such as diabetes, hypertension, and heart disease. Of interest, maternal thinness is a strong predictor of both preterm birth and fetal growth restriction. However, in the United States, several nutritional interventions, including high-protein diets, caloric supplementation, calcium and iron supplementation, and various other vitamin and mineral supplementations, have not generally reduced preterm birth or growth restriction. Bacterial intrauterine infections play an important role in the etiology of the earliest preterm births, but, at least to date, antibiotic treatment either before labor for risk factors such as bacterial vaginosis or during preterm labor have not consistently reduced the preterm birth rate. Most interventions have failed to reduce preterm birth or growth restriction. The substantial improvement in newborn survival in the United States over the past several decades is mostly due to better access to improved neonatal care for low-birth-weight infants.

Predictors of response to 17-alpha hydroxyprogesterone caproate for prevention of recurrent spontaneous preterm birth.

PubMed

Manuck, Tracy A; Esplin, M Sean; Biggio, Joseph; Bukowski, Radek; Parry, Samuel; Zhang, Heping; Huang, Hao; Varner, Michael W; Andrews, William; Saade, George; Sadovsky, Yoel; Reddy, Uma M; Ilekis, John

2016-03-01

Prematurity is the leading cause of neonatal morbidity and death among nonanomalous neonates in the United States. Intramuscular 17-alpha hydroxyprogesterone caproate injections reduce the risk of recurrent prematurity by approximately one third. Unfortunately, prophylactic 17-alpha hydroxyprogesterone caproate is not always effective, and one-third of high-risk women will have a recurrent preterm birth, despite 17-alpha hydroxyprogesterone caproate therapy. The reasons for this variability in response are unknown. Previous investigators have examined the influence of a variety of factors on 17-alpha hydroxyprogesterone caproate response but have analyzed data that used a fixed outcome of term delivery to define progesterone response. We hypothesized that the demographics, history, and pregnancy course among women who deliver at a similar gestational age with 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth prevention differs when compared with those women who deliver later with 17-alpha hydroxyprogesterone caproate and that these associations could be refined by the use of a contemporary definition of 17-alpha hydroxyprogesterone caproate "responder." This was a planned secondary analysis of a prospective, multicenter, longitudinal study of women with ≥1 previous documented singleton spontaneous preterm birth at <37 weeks gestation. Data were collected at 3 prespecified gestational age epochs during pregnancy. All women who were included in this analysis received 17-alpha hydroxyprogesterone caproate during the studied pregnancy. We classified women as a 17-alpha hydroxyprogesterone caproate responder or nonresponder by calculating the difference in delivery gestational age between the 17-alpha hydroxyprogesterone caproate-treated pregnancy and her earliest spontaneous preterm birth. Responders were defined as those with pregnancy that extended ≥3 weeks later with 17-alpha hydroxyprogesterone caproate, compared with the delivery gestational age of their earliest previous spontaneous preterm birth. Data were analyzed with the use of chi-square test, t-test, and logistic regression. One hundred fifty-five women met the inclusion criteria. The 118 responders delivered later on average (37.7 weeks gestation) than the 37 nonresponders (33.5 weeks gestation; P < .001). Among responders, 32% (38/118 women) had a recurrent spontaneous preterm birth. Demographics (age, race/ethnicity, education, and parity) were similar between groups. In the regression model, the gestational age of the previous spontaneous preterm birth (odds ratio, 0.68; 95% confidence interval, 0.56-0.82; P < .001), vaginal bleeding/abruption in the current pregnancy (odds ratio, 0.24; 95% confidence interval, 0.06-0.88; P = .031), and first-degree family history of spontaneous preterm birth (odds ratio, 0.37; 95% confidence interval, 0.15-0.88; P = .024) were associated with response to 17-alpha hydroxyprogesterone caproate. Because women with a penultimate preterm pregnancy were more likely to be 17-alpha hydroxyprogesterone caproate nonresponders, we performed an additional limited analysis examining only the 130 women whose penultimate pregnancy was preterm. In regression models, the results were similar to those in the main cohort. Several historic and current pregnancy characteristics define women who are at risk for recurrent preterm birth at a similar gestational age, despite 17-alpha hydroxyprogesterone caproate therapy. These data should be studied prospectively in larger cohorts and combined with genetic and environmental data to identify women who are most likely to benefit from this intervention. Copyright © 2016 Elsevier Inc. All rights reserved.

Exercise during pregnancy in normal-weight women and risk of preterm birth: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Di Mascio, Daniele; Magro-Malosso, Elena Rita; Saccone, Gabriele; Marhefka, Gregary D; Berghella, Vincenzo

2016-11-01

Preterm birth is the major cause of perinatal mortality in the United States. In the past, pregnant women have been recommended to not exercise because of presumed risks of preterm birth. Physical activity has been theoretically related to preterm birth because it increases the release of catecholamines, especially norepinephrine, which might stimulate myometrial activity. Conversely, exercise may reduce the risk of preterm birth by other mechanisms such as decreased oxidative stress or improved placenta vascularization. Therefore, the safety of exercise regarding preterm birth and its effects on gestational age at delivery remain controversial. The objective of the study was to evaluate the effects of exercise during pregnancy on the risk of preterm birth. MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID, and Cochrane Library were searched from the inception of each database to April 2016. Selection criteria included only randomized clinical trials of pregnant women randomized before 23 weeks to an aerobic exercise regimen or not. Types of participants included women of normal weight with uncomplicated, singleton pregnancies without any obstetric contraindication to physical activity. The summary measures were reported as relative risk or as mean difference with 95% confidence intervals. The primary outcome was the incidence of preterm birth <37 weeks. Of the 2059 women included in the meta-analysis, 1022 (49.6%) were randomized to the exercise group and 1037 (50.4%) to the control group. Aerobic exercise lasted about 35-90 minutes 3-4 times per week. Women who were randomized to aerobic exercise had a similar incidence of preterm birth of <37 weeks (4.5% vs 4.4%; relative risk, 1.01, 95% confidence interval, 0.68-1.50) and a similar mean gestational age at delivery (mean difference, 0.05 week, 95% confidence interval, -0.07 to 0.17) compared with controls. Women in the exercise group had a significantly higher incidence of vaginal delivery (73.6% vs 67.5%; relative risk, 1.09, 95% confidence interval, 1.04-1.15) and a significantly lower incidence of cesarean delivery (17.9% vs 22%; relative risk, 0.82, 95% confidence interval, 0.69-0.97) compared with controls. The incidence of operative vaginal delivery (12.9% vs 16.5%; relative risk, 0.78, 95% confidence interval, 0.61-1.01) was similar in both groups. Women in the exercise group had a significantly lower incidence of gestational diabetes mellitus (2.9% vs 5.6%; relative risk, 0.51, 95% confidence interval, 0.31-0.82) and a significantly lower incidence of hypertensive disorders (1.0% vs 5.6%; relative risk, 0.21, 95% confidence interval, 0.09-0.45) compared with controls. No differences in low birthweight (5.2% vs 4.7%; relative risk, 1.11, 95% confidence interval, 0.72-1.73) and mean birthweight (mean difference, -10.46 g, 95% confidence interval, -47.10 to 26.21) between the exercise group and controls were found. Aerobic exercise for 35-90 minutes 3-4 times per week during pregnancy can be safely performed by normal-weight women with singleton, uncomplicated gestations because this is not associated with an increased risk of preterm birth or with a reduction in mean gestational age at delivery. Exercise was associated with a significantly higher incidence of vaginal delivery and a significantly lower incidence of cesarean delivery, with a significantly lower incidence of gestational diabetes mellitus and hypertensive disorders and therefore should be encouraged. Copyright © 2016. Published by Elsevier Inc.

Combination Antiretroviral Use and Preterm Birth

PubMed Central

Watts, D. Heather; Williams, Paige L.; Kacanek, Deborah; Griner, Raymond; Rich, Kenneth; Hazra, Rohan; Mofenson, Lynne M.; Mendez, Hermann A.

2013-01-01

Background. Use of antiretroviral drugs (ARVs) during pregnancy has been associated with higher risk of preterm birth. Methods. The Pediatric HIV/AIDS Cohort Study network's Surveillance Monitoring for ART Toxicities study is a US-based cohort of human immunodeficiency virus (HIV)–exposed uninfected children. We evaluated maternal ARV use during pregnancy and the risk of any type of preterm birth (ie, birth before 37 completed weeks of gestation), the risk of spontaneous preterm birth (ie, preterm birth that occurred after preterm labor or membrane rupture, without other complications), and the risk of small for gestational age (SGA; ie, a birth weight of <10th percentile for gestational age). Multivariable logistic regression models were used to evaluate the association of ARVs and timing of exposure, while adjusting for maternal characteristics. Results. Among 1869 singleton births, 18.6% were preterm, 10.2% were spontaneous preterm, and 7.3% were SGA. A total of 89% used 3-drug combination ARV regimens during pregnancy. In adjusted models, the odds of preterm birth and spontaneous preterm birth were significantly greater among mothers who used protease inhibitors during the first trimester (adjusted odds ratios, 1.55 and 1.59, respectively) but not among mothers who used nonnucleoside reverse-transcriptase inhibitor or triple-nucleoside regimens during the first trimester. Combination ARV exposure starting later in pregnancy was not associated with increased risk. No associations were observed between SGA and exposure to combination ARV regimens. Conclusions. Protease inhibitor use early in pregnancy may be associated with increased risk for prematurity. PMID:23204173

The contribution of preterm birth to the Black-White infant mortality gap, 1990 and 2000.

PubMed

Schempf, Ashley H; Branum, Amy M; Lukacs, Susan L; Schoendorf, Kenneth C

2007-07-01

We evaluated whether the decline of the racial disparity in preterm birth during the last decade was commensurate with a decline in the contribution of preterm birth to the infant mortality gap. We used linked files of 1990 and 2000 data on US infant births and deaths to partition the gap between Black and White infant mortality rates into differences in the (1) distribution of gestational age and (2) gestational age-specific mortality rates. Between 1990 and 2000, the Black-White infant mortality rate ratio did not change significantly (2.3 vs 2.4). Excess deaths among preterm Black infants accounted for nearly 80% of the Black-White infant mortality gap in both 1990 and 2000. The narrowing racial disparity in the preterm birth rate was counterbalanced by greater mortality reductions in White than in Black preterm infants. Extremely preterm birth (<28 weeks) was 4 times higher in Black infants and accounted for more than half of the infant mortality gap. Substantial reductions in the Black-White infant mortality gap will require improved prevention of extremely preterm birth among Black infants.

The association between short interpregnancy interval and preterm birth in Louisiana: a comparison of methods.

PubMed

Howard, Elizabeth J; Harville, Emily; Kissinger, Patricia; Xiong, Xu

2013-07-01

There is growing interest in the application of propensity scores (PS) in epidemiologic studies, especially within the field of reproductive epidemiology. This retrospective cohort study assesses the impact of a short interpregnancy interval (IPI) on preterm birth and compares the results of the conventional logistic regression analysis with analyses utilizing a PS. The study included 96,378 singleton infants from Louisiana birth certificate data (1995-2007). Five regression models designed for methods comparison are presented. Ten percent (10.17 %) of all births were preterm; 26.83 % of births were from a short IPI. The PS-adjusted model produced a more conservative estimate of the exposure variable compared to the conventional logistic regression method (β-coefficient: 0.21 vs. 0.43), as well as a smaller standard error (0.024 vs. 0.028), odds ratio and 95 % confidence intervals [1.15 (1.09, 1.20) vs. 1.23 (1.17, 1.30)]. The inclusion of more covariate and interaction terms in the PS did not change the estimates of the exposure variable. This analysis indicates that PS-adjusted regression may be appropriate for validation of conventional methods in a large dataset with a fairly common outcome. PS's may be beneficial in producing more precise estimates, especially for models with many confounders and effect modifiers and where conventional adjustment with logistic regression is unsatisfactory. Short intervals between pregnancies are associated with preterm birth in this population, according to either technique. Birth spacing is an issue that women have some control over. Educational interventions, including birth control, should be applied during prenatal visits and following delivery.

Preterm Birth and Adult Wealth: Mathematics Skills Count.

PubMed

Basten, Maartje; Jaekel, Julia; Johnson, Samantha; Gilmore, Camilla; Wolke, Dieter

2015-10-01

Each year, 15 million babies worldwide are born preterm. Preterm birth is associated with adverse neurodevelopmental outcomes across the life span. Recent registry-based studies suggest that preterm birth is associated with decreased wealth in adulthood, but the mediating mechanisms are unknown. This study investigated whether the relationship between preterm birth and low adult wealth is mediated by poor academic abilities and educational qualifications. Participants were members of two British population-based birth cohorts born in 1958 and 1970, respectively. Results showed that preterm birth was associated with decreased wealth at 42 years of age. This association was mediated by decreased intelligence, reading, and, in particular, mathematics attainment in middle childhood, as well as decreased educational qualifications in young adulthood. Findings were similar in both cohorts, which suggests that these mechanisms may be time invariant. Special educational support in childhood may prevent preterm children from becoming less wealthy as adults. © The Author(s) 2015.

Preterm birth research: from disillusion to the search for new mechanisms.

PubMed

Buekens, P; Klebanoff, M

2001-07-01

No intervention has been shown to decrease the rate of preterm birth. There was thus a need for a new research agenda. The new emphasis is on social and biological mechanisms, including the impact on stress of racism and poverty, and gene-environment interactions. New markers are also under study, and pertain mostly to infection and inflammation. The impact on preterm birth of broad contextual factors, such as universal social protection, will need to be explored further. The recent trends toward increased rates of preterm births deserve much attention. New policies and interventions to decrease medically indicated preterm births should be urgently developed and evaluated. The failure to prevent preterm deliveries has been so disappointing that there is a risk that high rates of preterm births will be seen as unavoidable. The research programme launched by March of Dimes is a timely effort to foster new enthusiasm, to test new ideas and to generate new hypotheses.

The interaction between vaginal microbiota, cervical length, and vaginal progesterone treatment for preterm birth risk.

PubMed

Kindinger, Lindsay M; Bennett, Phillip R; Lee, Yun S; Marchesi, Julian R; Smith, Ann; Cacciatore, Stefano; Holmes, Elaine; Nicholson, Jeremy K; Teoh, T G; MacIntyre, David A

2017-01-19

Preterm birth is the primary cause of infant death worldwide. A short cervix in the second trimester of pregnancy is a risk factor for preterm birth. In specific patient cohorts, vaginal progesterone reduces this risk. Using 16S rRNA gene sequencing, we undertook a prospective study in women at risk of preterm birth (n = 161) to assess (1) the relationship between vaginal microbiota and cervical length in the second trimester and preterm birth risk and (2) the impact of vaginal progesterone on vaginal bacterial communities in women with a short cervix. Lactobacillus iners dominance at 16 weeks of gestation was significantly associated with both a short cervix <25 mm (n = 15, P < 0.05) and preterm birth <34 +0  weeks (n = 18; P < 0.01; 69% PPV). In contrast, Lactobacillus crispatus dominance was highly predictive of term birth (n = 127, 98% PPV). Cervical shortening and preterm birth were not associated with vaginal dysbiosis. A longitudinal characterization of vaginal microbiota (<18, 22, 28, and 34 weeks) was then undertaken in women receiving vaginal progesterone (400 mg/OD, n = 25) versus controls (n = 42). Progesterone did not alter vaginal bacterial community structure nor reduce L. iners-associated preterm birth (<34 weeks). L. iners dominance of the vaginal microbiota at 16 weeks of gestation is a risk factor for preterm birth, whereas L. crispatus dominance is protective against preterm birth. Vaginal progesterone does not appear to impact the pregnancy vaginal microbiota. Patients and clinicians who may be concerned about "infection risk" associated with the use of a vaginal pessary during high-risk pregnancy can be reassured.

International comparisons of preterm birth: higher rates of late preterm birth are associated with lower rates of stillbirth and neonatal death.

PubMed

Lisonkova, S; Sabr, Y; Butler, B; Joseph, K S

2012-12-01

To examine international rates of preterm birth and potential associations with stillbirths and neonatal deaths at late preterm and term gestation. Ecological study. Canada, USA and 26 countries in Europe. All deliveries in 2004. Information on preterm birth (<37, 32-36, 28-31 and 24-27 weeks of gestation) and perinatal deaths was obtained for 28 countries. Data sources included files and publications from Statistics Canada, the EURO-PERISTAT project and the National Center for Health Statistics. Pearson correlation coefficients and random-intercept Poisson regression were used to examine the association between preterm birth rates and gestational age-specific stillbirth and neonatal death rates. Rate ratios with 95% confidence intervals were estimated after adjustment for maternal age, parity and multiple births. Stillbirths and neonatal deaths ≥ 32 and ≥ 37 weeks of gestation. International rates of preterm birth (<37 weeks) ranged between 5.3 and 11.4 per 100 live births. Preterm birth rates at 32-36 weeks were inversely associated with stillbirths at ≥ 32 weeks (adjusted rate ratio 0.94, 95% CI 0.92-0.96) and ≥ 37 weeks (adjusted rate ratio 0.88, 95% CI 0.85-0.91) of gestation and inversely associated with neonatal deaths at ≥ 32 weeks (adjusted rate ratio 0.88, 95% CI 0.85-0.91) and ≥ 37 weeks (adjusted rate ratio 0.82, 95% CI 0.78-0.86) of gestation. Countries with high rates of preterm birth at 32-36 weeks of gestation have lower stillbirth and neonatal death rates at and beyond 32 weeks of gestation. Contemporary rates of preterm birth are indicators of both perinatal health and obstetric care services. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

A time-series analysis of any short-term effects of meteorological and air pollution factors on preterm births in London, UK.

PubMed

Lee, Sue J; Hajat, Shakoor; Steer, Philip J; Filippi, Veronique

2008-02-01

Although much is known about the incidence and burden of preterm birth, its biological mechanisms are not well understood. While several studies have suggested that high levels of air pollution or exposure to particular climatic factors may be associated with an increased risk of preterm birth, other studies do not support such an association. To determine whether exposure to various environmental factors place a large London-based population at higher risk for preterm birth, we analyzed 482,568 births that occurred between 1988 and 2000 from the St. Mary's Maternity Information System database. Using an ecological study design, any short-term associations between preterm birth and various environmental factors were investigated using time-series regression techniques. Environmental exposures included air pollution (ambient ozone and PM(10)) and climatic factors (temperature, rainfall, sunshine, relative humidity, barometric pressure, and largest drop in barometric pressure). In addition to exposure on the day of birth, cumulative exposure up to 1 week before birth was investigated. The risk of preterm birth did not increase with exposure to the levels of ambient air pollution or meteorological factors experienced by this population. Cumulative exposure from 0 to 6 days before birth also did not show any significant effect on the risk of preterm birth. This large study, covering 13 years, suggests that there is no association between preterm births and recent exposure to ambient air pollution or recent changes in the weather.

Early term and late preterm birth are associated with poorer school performance at age 5 years: a cohort study.

PubMed

Quigley, Maria A; Poulsen, Gry; Boyle, Elaine; Wolke, Dieter; Field, David; Alfirevic, Zarko; Kurinczuk, Jennifer J

2012-05-01

To compare school performance at age 5 years in children born at full term (39-41 weeks gestation) with those born at early term (37-38 weeks gestation), late preterm (34-36 weeks gestation), moderately preterm (32-33 weeks gestation) and very preterm (<32 weeks gestation). Population-based cohort (UK Millennium Cohort Study). Seven thousand six hundred and fifty children born in 2000-2001 and attending school in England in 2006. School performance was measured using the foundation stage profile (FSP), a statutory assessment by teachers at the end of the child's first school year. The FSP comprises 13 assessment scales (scored from 1 to 9). Children who achieve an average of 6 points per scale and at least 6 in certain scales are classified as 'reaching a good level of overall achievement'. Fifty-one per cent of full term children had not reached a good level of overall achievement; this proportion increased with prematurity (55% in early term, 59% in late preterm, 63% in moderately preterm and 66% in very preterm children). Compared with full term children, an elevated risk remained after adjustment, even in early term (adjusted RR 1.05, 95% 1.00 to 1.11) and late preterm children (adjusted RR 1.12, 95% CI 1.04 to 1.22). Similar effects were noted for 'not working securely' in mathematical development, physical development and creative development. The effects of late preterm and early term birth were small in comparison with other risk factors. Late preterm and early term birth are associated with an increased risk of poorer educational achievement at age 5 years.

Morbidity and mortality among very preterm singletons following fertility treatment in Australia and New Zealand, a population cohort study.

PubMed

Wang, Alex Y; Chughtai, Abrar A; Lui, Kei; Sullivan, Elizabeth A

2017-02-02

Due to high rates of multiple birth and preterm birth following fertility treatment, the rates of mortality and morbidity among births following fertility treatment were higher than those conceived spontaneously. However, it is unclear whether the rates of adverse neonatal outcomes remain higher for very preterm (<32 weeks gestational age) singletons born after fertility treatment. This study aims to compare adverse neonatal outcomes among very preterm singletons born after fertility treatment including assisted reproductive technology (ART) hyper-ovulution (HO) and artificial insemination (AI) to those following spontaneous conception. The population cohort study included 24069 liveborn very preterm singletons who were admitted to Neonatal Intensive Care Unit (NICU) in Australia and New Zealand from 2000 to 2010. The in-hospital neonatal mortality and morbidity among 21753 liveborn very preterm singletons were compared by maternal mode of conceptions: spontaneous conception, HO, ART and AI. Univariate and multivariate binary logistic regression analysis was used to examine the association between mode of conception and various outcome factors. Odds ratio (OR) and adjusted odds ratio (AOR) and 95% confidence interval (CI) were calculated. The rate of small for gestational age was significantly higher in HO group (AOR 1.52, 95% CI 1.02-2.67) and AI group (AOR 2.98, 95% CI 1.53-5.81) than spontaneous group. The rate of birth defect was significantly higher in ART group (AOR 1.71, 95% CI 1.36-2.16) and AI group (AOR 3.01, 95% CI 1.47-6.19) compared to spontaneous group. Singletons following ART had 43% increased odds of necrotizing enterocolitis (AOR 1.43, 95% CI 1.04-1.97) and 71% increased odds of major surgery (AOR 1.71, 95% CI 1.37-2.13) compared to singletons conceived spontaneously. Other birth and NICU outcomes were not different among the comparison groups. Compared to the spontaneous conception group, risk of congenital abnormality significantly increases after ART and AI; the risk of morbidities increases after ART, HO and AI. Preconception planning should include comprehensive information about the benefits and risks of fertility treatment on the neonatal outcomes.

Factors That Influence Human Milk Feeding at Hospital Discharge for Preterm Infants in a Tertiary Neonatal Care Center in Taiwan.

PubMed

Pai, Chia-Ming; Jim, Wai-Tim; Lin, Hsiang-Yu; Hsu, Chyong-Hsin; Kao, Hsin-An; Hung, Han-Yang; Peng, Chun-Chih; Chang, Jui-Hsing

Human milk is considered optimal nutrition for newborn infants, especially preterm infants, and it can lessen morbidity in this population. Human milk feeding at hospital discharge may encourage breastfeeding at home. This study evaluated the incidence and predictive factors of human milk feeding of preterm infants at discharge. It included all preterm infants with gestational age of less than 37 weeks who were admitted to the Mackay Memorial Hospital in Taiwan from January to December 2010 who survived to discharge. Infants were classified into a human milk group or a formula milk group. Gestational age, birth weight, length of hospital stay, maternal age, maternal educational status, and morbidity of prematurity were compared between the groups. Of the 290 preterm infants, 153 (52.8%) were being fed human milk at hospital discharge. Compared with the formula milk group, the human milk group had lower birth weights, younger gestational age, higher rates of ventilator use, and longer hospital stays. These differences were not statistically significant for very low-birth-weight (birth weight of <1500 g) infants (n = 66). Multivariate analysis indicated that 2 factors, longer hospital stay and neonatal intensive care unit admission, were associated with human milk feeding at hospital discharge. These findings highlight the need for encouraging and helping all mothers, even those with relatively mature and healthy infants, to provide human milk for their infants.

Antibiotics for asymptomatic bacteriuria in pregnancy.

PubMed

Smaill, F

2000-01-01

Up to 30% of mothers develop acute pyelonephritis if asymptomatic bacteriuria is untreated. Asymptomatic bacteriuria may have a role in preterm birth, or it may be a marker for low socioeconomic status and thus, low birth weight. The objective of this review was to assess the effect of antibiotic treatment for asymptomatic bacteriuria on persistent bacteriuria during pregnancy, the risk of preterm delivery and the development of pyelonephritis after delivery. I searched the Cochrane Pregnancy and Childbirth Group trials register. Randomised trials comparing antibiotic treatment with placebo or no treatment in pregnant women with asymptomatic bacteriuria found on antenatal screening. Trial quality was assessed. Thirteen studies were included. Overall the study quality was not strong. Antibiotic treatment compared to placebo or no treatment was effective in clearing asymptomatic bacteriuria (odds ratio 0.07, 95% confidence interval 0.05 to 0.10). The incidence of pyelonephritis was reduced (odds ratio 0.25, 95% confidence interval 0.19 to 0.32). Antibiotic treatment was also associated with a reduction in the incidence of preterm delivery or low birth weight babies (odds ratio 0.60, 95% confidence interval 0.45 to 0.80). Antibiotic treatment appears to be effective in reducing the risk of pyelonephritis in pregnancy. An apparent reduction in preterm delivery is consistent with current theories about the role of infection in preterm birth, but this association should be interpreted with caution.

Antibiotics for asymptomatic bacteriuria in pregnancy.

PubMed

Smaill, F

2001-01-01

Up to 30% of mothers develop acute pyelonephritis if asymptomatic bacteriuria is untreated. Asymptomatic bacteriuria may have a role in preterm birth or it may be a marker for low socioeconomic status which is associated with low birth weight. The objective of this review was to assess the effect of antibiotic treatment for asymptomatic bacteriuria on persistent bacteriuria during pregnancy, the risk of preterm delivery, and the development of pyelonephritis. I searched the Cochrane Pregnancy and Childbirth Group trials register. Date of last search: December 2000. Randomised trials comparing antibiotic treatment with placebo or no treatment in pregnant women with asymptomatic bacteriuria found on antenatal screening. Trial quality was assessed. Fourteen studies were included. Overall the study quality was not strong. Antibiotic treatment compared to placebo or no treatment was effective in clearing asymptomatic bacteriuria (odds ratio 0.07, 95% confidence interval 0.05 to 0.10). The incidence of pyelonephritis was reduced (odds ratio 0.24, 95% confidence interval 0.19 to 0.32). Antibiotic treatment was also associated with a reduction in the incidence of preterm delivery or low birth weight babies (odds ratio 0.60, 95% confidence interval 0.45 to 0.80). Antibiotic treatment is effective in reducing the risk of pyelonephritis in pregnancy. An apparent reduction in preterm delivery is consistent with current theories about the role of infection in preterm birth, but this association should be interpreted with caution.

Determining the prevalence of cytomegalovirus infection in a cohort of preterm infants.

PubMed

Pitlick, Mitchell M; Orr, Kristin; Momany, Allison M; McDonald, Erin L; Murray, Jeffrey C; Ryckman, Kelli K

2015-01-01

Preterm birth is a global public health problem that is a significant cause of infant morbidity and mortality. Congenital cytomegalovirus (CMV) infection has been proposed as a risk factor for preterm birth, but the rate of CMV in infants born preterm is unclear. CMV is the leading infectious cause of sensorineural hearing loss, which will affect 15% - 20% of congenitally infected infants later in their childhood. 90% of infected infants are asymptomatic at birth and are not recognized as at risk for CMV-associated deficits. To determine the prevalence of CMV infection in a large cohort of preterm infants. DNA was extracted from cord blood, peripheral blood, saliva, and buccal swab samples collected from preterm infants. A total of 1200 unique DNA samples were tested for CMV using a nested PCR protocol. The proportions of preterm infants with CMV was compared by sample collection type, race, gender, and gestational age. A total of 37 infants tested positive for CMV (3.08%). After excluding twins, siblings, and infants older than two weeks at the time of sample collection, two out of 589 infants were CMV positive (0.3%), which was lower than the proportion of CMV observed in the general population. All positive samples came from buccal swabs. Our work suggests that while CMV infection may not be greater in preterm infants than in the general population, given the neurologic consequences of CMV in preterm infants, screening of this population may still be warranted. If so, our results suggest buccal swabs, collected at pregnancy or at birth, may be an ideal method for such a program.

Preeclampsia and retinopathy of prematurity in preterm births.

PubMed

Yu, Xiao Dan; Branch, D Ware; Karumanchi, S Ananth; Zhang, Jun

2012-07-01

The relationship between gestational hypertension, preeclampsia, and the risk of retinopathy of prematurity (ROP) remains unclear. Thus, we used a large cohort database to study the influence of maternal gestational hypertension and preeclampsia on the occurrence of ROP in preterm infants. We used data from a previous retrospective cohort study that includes 25,473 eligible preterm neonates. We examined the association between gestational hypertension, preeclampsia, and ROP while controlling for potential confounders by multiple logistic regression analysis. Of the 8758 early preterm infants (gestational age <34 weeks), 1024 (11.69%) had ROP, while of the 16,715 late preterm infants, only 29 (0.17%) had ROP. After adjusting for confounders, preeclampsia was associated with a significantly reduced risk of ROP (adjusted odds ratio [aOR], 0.65; 95% confidence interval [CI], 0.49-0.86 for early preterm birth; aOR, 0.10; 95% CI, 0.01-0.93 for late preterm birth; aOR, 0.66; 95% CI, 0.50-0.87 for all preterm births). Gestational hypertension was not significantly associated with ROP at early or late preterm births. Preeclampsia, but not gestational hypertension, was associated with a reduced risk of ROP in preterm births.

Perinatal outcome of singleton siblings born after assisted reproductive technology and spontaneous conception: Danish national sibling-cohort study.

PubMed

Henningsen, Anna-Karina Aaris; Pinborg, Anja; Lidegaard, Øjvind; Vestergaard, Christina; Forman, Julie Lyng; Andersen, Anders Nyboe

2011-03-01

To compare the perinatal outcome of singleton siblings conceived differently. National population-based registry study. Denmark, from 1994 to 2008. Pairs of siblings (13,692 pairs; n = 27,384 children) conceived after IVF, intracytoplasmatic sperm injection (ICSI), frozen embryo replacement (FER), or spontaneous conception subcategorized into five groups according to succession: [1] IVF-ICSI vs. spontaneous conception (n = 7,758), [2] IVF-ICSI vs. FER (n = 716), [3] FER vs. FER (n = 34), [4] IVF-ICSI vs. IVF-ICSI (n = 2,876), and [5] spontaneous conception vs. spontaneous conception (n = 16,000). Observations were obtained from national registries. Birth weight, gestational age, low birth weight (<2,500 g), preterm birth (<37 weeks' gestation) and perinatal deaths. Mean birth weight was 65 g (95% confidence interval [CI], 41-89] lower in all assisted reproductive technology children compared with their spontaneously conceived siblings. FER children were 167 g (95% CI, 90-244] heavier than siblings born after replacement of fresh embryos. The difference in birth weight between firstborn and second born sibling depended on order of conception method. Higher risk of low birth weight with (odds ratio [OR], 1.4; 95%CI, 1.1-1.7] and preterm birth (OR, 1.3; 95% CI, 1.1-1.6] was observed in IVF/ICSI compared with spontaneous conception. When differentiating between order and mode of conception, it seems that assisted reproductive technology plays a role in mean birth weight and risk of low birth weight and preterm birth. Birth weight was higher in siblings born after FER compared with fresh embryos replacement. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Birth Outcomes of Latin Americans in Two Countries with Contrasting Immigration Admission Policies: Canada and Spain.

PubMed

Urquia, Marcelo L; Vang, Zoua M; Bolumar, Francisco

2015-01-01

We delved into the selective migration hypothesis on health by comparing birth outcomes of Latin American immigrants giving birth in two receiving countries with dissimilar immigration admission policies: Canada and Spain. We hypothesized that a stronger immigrant selection in Canada will reflect more favourable outcomes among Latin Americans giving birth in Canada than among their counterparts giving birth in Spain. We conducted a cross-sectional bi-national comparative study. We analyzed birth data of singleton infants born in Canada (2000-2005) (N = 31,767) and Spain (1998-2007) (N = 150,405) to mothers born in Spanish-speaking Latin American countries. We compared mean birthweight at 37-41 weeks gestation, and low birthweight and preterm birth rates between Latin American immigrants to Canada vs. Spain. Regression analysis for aggregate data was used to obtain Odds Ratios and Mean birthweight differences adjusted for infant sex, maternal age, parity, marital status, and father born in same source country. Latin American women in Canada had heavier newborns than their same-country counterparts giving birth in Spain, overall [adjusted mean birthweight difference: 101 grams; 95% confidence interval (CI): 98, 104], and within each maternal country of origin. Latin American women in Canada had fewer low birthweight and preterm infants than those giving birth in Spain [adjusted Odds Ratio: 0.88; 95% CI: 0.82, 0.94 for low birthweight, and 0.88; 95% CI: 0.84, 0.93 for preterm birth, respectively]. Latin American immigrant women had better birth outcomes in Canada than in Spain, suggesting a more selective migration in Canada than in Spain.

Towards BirthAlert—A Clinical Device Intended for Early Preterm Birth Detection

PubMed Central

Etemadi, Mozziyar; Chung, Philip; Heller, J. Alex; Liu, Jonathan A.; Rand, Larry; Roy, Shuvo

2015-01-01

Preterm birth causes 1 million infant deaths worldwide every year, making it the leading cause of infant mortality. Existing diagnostic tests such as transvaginal ultrasound or fetal fibronectin either cannot determine if preterm birth will occur in the future or can only predict the occurrence once cervical shortening has begun, at which point it is too late to reverse the accelerated parturition process. Using iterative and rapid prototyping techniques, we have developed an intravaginal proof-of-concept device that measures both cervical bioimpedance and cervical fluorescence to characterize microstructural changes in a pregnant woman's cervix in hopes of detecting preterm birth before macroscopic changes manifest in the tissue. If successful, such an early alert during this “silent phase” of the preterm birth syndrome may open a new window of opportunity for interventions that may reverse and avoid preterm birth altogether. PMID:23893706

Association between periodontitis, periodontopathogens and preterm birth: is it real?

PubMed

Martínez-Martínez, Rita Elizabeth; Moreno-Castillo, Diana Francisca; Loyola-Rodríguez, Juan Pablo; Sánchez-Medrano, Ana Gabriela; Miguel-Hernández, Jesús Héctor San; Olvera-Delgado, José Honorio; Domínguez-Pérez, Rubén Abraham

2016-07-01

To identify the association between periodontitis and periodontal pathogens with preterm birth despite the strict control of some important confounders, such as infectious processes and criteria for diagnosis of periodontitis during pregnancy. In this cross-sectional study were included 70 healthy puerperal women between 20 and 35 years without a history of genitourinary infections during pregnancy. Based on the gestational age they were divided into two groups: 45 with term birth (>37 weeks) and 25 with preterm birth (<37 weeks). Previous informed consent, a gynecologic and dental history that included gynecologic and obstetric background, periodontal status applying different authors' criteria of periodontitis diagnosis, presence of periodontopathogens, dental caries and oral hygiene were recorded. There was no association between periodontitis, periodontopathogens and preterm birth. There were no statistical differences applying different authors' criteria diagnosis of periodontitis. Gingivitis status was similar, but probing depth was greater in preterm birth subjects, perhaps they are young women, and this finding could be an early sign of periodontitis. In like manner, the main periodontal bacterial species are not associated with preterm birth, general hygiene and care habits are poorer than term birth subjects. We could suggest that preterm birth is a multifactorial condition and the role of periodontitis and the periodontopathogens itself is not sufficient to trigger the preterm birth. There are factors such as infectious processes and diagnostic criteria for periodontitis that could be responsible for controversial results.

Specialist antenatal clinics for women at high risk of preterm birth: a systematic review of qualitative and quantitative research.

PubMed

Malouf, Reem; Redshaw, Maggie

2017-02-02

Preterm birth (PTB) is the leading cause of perinatal morbidity and mortality. Women with previous prenatal loss are at higher risk of preterm birth. A specialist antenatal clinic is considered as one approach to improve maternity and pregnancy outcomes. A systematic review of quantitative, qualitative and mixed method studies conducted on women at high risk of preterm birth (PTB). The review primary outcomes were to report on the specialist antenatal clinics effect in preventing or reducing preterm birth, perinatal mortality and morbidity and women's perceptions and experiences of a specialist clinic whether compared or not compared with standard antenatal care. Other secondary maternal, infant and economic outcomes were also determined. A comprehensive search strategy was carried out in English within electronic databases as far back as 1980. The reviewers selected studies, assessed the quality, and extracted data independently. Results were summarized and tabulated. Eleven studies fully met the review inclusion criteria, ten were quantitative design studies and only one was a qualitative design study. No mixed method design study was included in the review. All were published after 1989, seven were conducted in the USA and four in the UK. Results from five good to low quality randomised controlled trials (RCTs), all conducted before 1990, did not illustrate the efficacy of the clinic in reducing preterm birth. Whereas results from more recent low quality cohort studies showed some positive neonatal outcomes. Themes from one good quality qualitative study reflected on the emotional and psychological need to reduce anxiety and stress of women referred to such a clinic. Women expressed their negative emotional responses at being labelled as high risk and positive responses to being assessed and treated in the clinic. Women also reported that their partners were struggling to cope emotionally. Findings from this review were mixed. Evidence from cohort studies indicated a specialist clinic may be a means of predicting or preventing preterm birth. Testing this in a randomised controlled trial is desirable, though may be hard to achieve due to the growing focus of such clinics on managing women at high risk of preterm birth. Ongoing research has to recognize women's experiences and perceptions of such a clinic. Further clarification of the optimal referral route and a clear and standardized management and cost economic evaluation plan are also required. Fathers support and experience of PTB clinics should also be included in further research.

Early preterm delivery due to placenta previa is an independent risk factor for a subsequent spontaneous preterm birth

PubMed Central

2012-01-01

Background To determine whether patients with placenta previa who delivered preterm have an increased risk for recurrent spontaneous preterm birth. Methods This retrospective population based cohort study included patients who delivered after a primary cesarean section (n = 9983). The rate of placenta previa, its recurrence, and the risk for recurrent preterm birth were determined. Results Patients who had a placenta previa at the primary CS pregnancy had an increased risk for its recurrence [crude OR of 2.65 (95% CI 1.3-5.5)]. The rate of preterm birth in patients with placenta previa in the primary CS pregnancy was 55.9%; and these patients had a higher rate of recurrent preterm delivery than the rest of the study population (p < .001). Among patients with placenta previa in the primary CS pregnancy, those who delivered preterm had a higher rate of recurrent spontaneous preterm birth regardless of the location of their placenta in the subsequent delivery [OR 3.09 (95% CI 2.1-4.6)]. In comparison to all patients with who had a primary cesarean section, patients who had placenta previa and delivered preterm had an independent increased risk for recurrent preterm birth [OR of 3.6 (95% CI 1.5-8.5)]. Conclusions Women with placenta previa, who deliver preterm, especially before 34 weeks of gestation, are at increased risk for recurrent spontaneous preterm birth regardless to the site of placental implantation in the subsequent pregnancy. Thus, strict follow up by high risk pregnancies specialist is recommended. PMID:22876799

Deployment and Adverse Pregnancy Outcomes: Primary Findings and Methodological Considerations.

PubMed

Katon, Jodie; Cypel, Yasmin; Raza, Mubashra; Zephyrin, Laurie; Reiber, Gayle; Yano, Elizabeth M; Barth, Shannon; Schneiderman, Aaron

2017-02-01

Objective To characterize the pregnancy outcomes of women Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans including prevalence of preterm delivery, low birth weight, and macrosomia, and to highlight methodological limitations that can impact findings. Methods A retrospective cohort study was conducted starting in 2014 analyzing data from the 2009 to 2011 National Health Study for a New Generation of US Veterans, which sampled Veterans deployed and not deployed to OIF/OEF. All pregnancies resulting in a live birth were included, and categorized as occurring among non-deployers, before deployment, during deployment, or after deployment. Outcomes included preterm birth, low birth weight, and macrosomia. The association of deployment with selected outcomes was estimated using separate general estimating equations to account for lack of outcome independence among women contributing multiple pregnancies. Adjustment variables included maternal age at outcome, and race/ethnicity. Results There were 2276 live births (191 preterm births, 153 low birth weight infants, and 272 macrosomic infants). Compared with pregnancies before deployment, pregnancies among non-deployers and those after deployment appeared to have greater risk of preterm birth [non-deployers: odds ratio (OR) = 2.16, 95 % confidence interval (CI) 1.25, 3.72; after deployment: OR = 1.90, 95 % CI 0.90, 4.02]. A similar pattern was observed for low birth weight. No association of deployment with macrosomia was detected. Discussion Compared with non-deployers, those who eventually deploy appear to have better pregnancy outcomes prior to deployment, but this advantage is no longer apparent after deployment. Non-deployers may not be an appropriate reference group to study the putative health impacts of deployment on pregnancy outcomes.

Rate of gestational weight gain, pre-pregnancy body mass index and preterm birth subtypes: a retrospective cohort study from Peru

PubMed Central

Carnero, AM; Mejía, CR; García, PJ

2014-01-01

Objective To examine the shape (functional form) of the association between the rate of gestational weight gain, pre-pregnancy body mass index (BMI), and preterm birth and its subtypes. Design Retrospective cohort study. Setting National reference obstetric centre in Lima, Peru. Population Pregnant women who delivered singleton babies during the period 2006–2009, resident in Lima, and beginning prenatal care at ≤12 weeks of gestation (n = 8964). Methods Data were collected from the centre database. The main analyses consisted of logistic regression with fractional polynomial modelling. Main outcome measures Preterm birth and its subtypes. Results Preterm birth occurred in 12.2% of women, being mostly idiopathic (85.7%). The rate of gestational weight gain was independently associated with preterm birth, and the shape of this association varied by pre-pregnancy BMI. In women who were underweight, the association was linear (per 0.1 kg/week increase) and protective (OR 0.88; 95% CI 0.82–1.00). In women of normal weight or who were overweight, the association was U-shaped: the odds of delivering preterm increased exponentially with rates <0.10 or >0.66 kg/week, and <0.04 or >0.50 kg/week, respectively. In women who were obese, the association was linear, but nonsignificant (OR 1.01; 95% CI 0.95–1.06). The association described for preterm birth closely resembled that of idiopathic preterm birth, although the latter was stronger. The rate of gestational weight gain was not associated with indicated preterm birth or preterm prelabour rupture of membranes. Conclusions In Peruvian pregnant women starting prenatal care at ≤12 weeks of gestation, the rate of gestational weight gain is independently associated with preterm birth, mainly because of its association with idiopathic preterm birth, and the shape of both associations varies by pre-pregnancy BMI. PMID:22607522

Rate of gestational weight gain, pre-pregnancy body mass index and preterm birth subtypes: a retrospective cohort study from Peru.

PubMed

Carnero, A M; Mejía, C R; García, P J

2012-07-01

To examine the shape (functional form) of the association between the rate of gestational weight gain, pre-pregnancy body mass index (BMI), and preterm birth and its subtypes.   Retrospective cohort study.   National reference obstetric centre in Lima, Peru.   Pregnant women who delivered singleton babies during the period 2006-2009, resident in Lima, and beginning prenatal care at ≤ 12 weeks of gestation (n=8964).   Data were collected from the centre database. The main analyses consisted of logistic regression with fractional polynomial modelling.   Preterm birth and its subtypes.   Preterm birth occurred in 12.2% of women, being mostly idiopathic (85.7%). The rate of gestational weight gain was independently associated with preterm birth, and the shape of this association varied by pre-pregnancy BMI. In women who were underweight, the association was linear (per 0.1 kg/week increase) and protective (OR 0.88; 95% CI 0.82-1.00). In women of normal weight or who were overweight, the association was U-shaped: the odds of delivering preterm increased exponentially with rates <0.10 or >0.66 kg/week, and <0.04 or >0.50 kg/week, respectively. In women who were obese, the association was linear, but non-significant (OR 1.01; 95% CI 0.95-1.06). The association described for preterm birth closely resembled that of idiopathic preterm birth, although the latter was stronger. The rate of gestational weight gain was not associated with indicated preterm birth or preterm prelabour rupture of membranes.   In Peruvian pregnant women starting prenatal care at ≤ 12 weeks of gestation, the rate of gestational weight gain is independently associated with preterm birth, mainly because of its association with idiopathic preterm birth, and the shape of both associations varies by pre-pregnancy BMI. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

[Description and evaluation of creative thinking in preterm low birth weight infants].

PubMed

Parisi, L; Di Filippo, T; Firrigno, L; La Grutta, S; Testa, D; Roccella, M

2007-04-01

Since the 1950s, the problem of how to evaluate creativity has been addressed in studies on the definition of measurement criteria and on the relationship between intelligence and creative thinking. Many revealed cognitive and relational disorders in preterm infants, particularly in preterm very low birth weight infants (birth weight <1500 g) and in infants with serious complications. This study describes the development of creative thinking in a group of children born preterm. The study sample was 43 children (21 males, 22 females; age range 6-11 years), regularly attending school, born with low birth weight (1050-2450 g) at 29-32 weeks gestational age, and compared with a control group with birth weight >2500 g. The test battery included: Torrance Test of Creative Thinking (TCTT); WISC-R intelligence test; Goodenough Human Figure Drawing Test. Statistical analysis (Mann-Whitney U test) showed a statistically significant difference (P>0.05) between the 2 groups; scores for figure originality, figure fluidity and figure elaboration were consistently higher in the control group. Within the low birth weight group, there was a significant correlation (Spearman r) between verbal IQ and verbal fluidity and verbal flexibility subscale scores and between IQ performance and figure elaboration. Scores on the figure drawing tests showed higher creative ability in the control group. In children born preterm with low birth weight, emotive dynamics and flow of affection may influence the channels of communication between child and family. The low figure originality subscale scores support the hypothesis that psychodynamic and relational factors (worry about the preterm condition, overprotective behaviour by parents and others) could lead to diminished autonomy, flexibility and manipulatory interest in the child.

Preterm birth--prediction, prevention, and consequences: an unmet challenge to perinatal medicine, science, and society: the declaration of Dubrovnik.

PubMed

Kurjak, Asim

2010-11-01

Preterm birth is the defining challenge to modern perinatal medicine. It is now clear that preterm birth is not caused by one pathologic process but many, some not identified. Prevention of preterm birth is possible if perinatal medicine, science, and society give the necessary priority to this most urgent problem of maternal, fetal, and neonatal patients.

Prevalence and risk factors related to preterm birth in Brazil.

PubMed

Leal, Maria do Carmo; Esteves-Pereira, Ana Paula; Nakamura-Pereira, Marcos; Torres, Jacqueline Alves; Theme-Filha, Mariza; Domingues, Rosa Maria Soares Madeira; Dias, Marcos Augusto Bastos; Moreira, Maria Elizabeth; Gama, Silvana Granado

2016-10-17

The rate of preterm birth has been increasing worldwide, including in Brazil. This constitutes a significant public health challenge because of the higher levels of morbidity and mortality and long-term health effects associated with preterm birth. This study describes and quantifies factors affecting spontaneous and provider-initiated preterm birth in Brazil. Data are from the 2011-2012 "Birth in Brazil" study, which used a national population-based sample of 23,940 women. We analyzed the variables following a three-level hierarchical methodology. For each level, we performed non-conditional multiple logistic regression for both spontaneous and provider-initiated preterm birth. The rate of preterm birth was 11.5 %, (95 % confidence 10.3 % to 12.9 %) 60.7 % spontaneous - with spontaneous onset of labor or premature preterm rupture of membranes - and 39.3 % provider-initiated, with more than 90 % of the last group being pre-labor cesarean deliveries. Socio-demographic factors associated with spontaneous preterm birth were adolescent pregnancy, low total years of schooling, and inadequate prenatal care. Other risk factors were previous preterm birth (OR 3.74; 95 % CI 2.92-4.79), multiple pregnancy (OR 16.42; 95 % CI 10.56-25.53), abruptio placentae (OR 2.38; 95 % CI 1.27-4.47) and infections (OR 4.89; 95 % CI 1.72-13.88). In contrast, provider-initiated preterm birth was associated with private childbirth healthcare (OR 1.47; 95 % CI 1.09-1.97), advanced-age pregnancy (OR 1.27; 95 % CI 1.01-1.59), two or more prior cesarean deliveries (OR 1.64; 95 % CI 1.19-2.26), multiple pregnancy (OR 20.29; 95 % CI 12.58-32.72) and any maternal or fetal pathology (OR 6.84; 95 % CI 5.56-8.42). The high proportion of provider-initiated preterm birth and its association with prior cesarean deliveries and all of the studied maternal/fetal pathologies suggest that a reduction of this type of prematurity may be possible. The association of spontaneous preterm birth with socially-disadvantaged groups reaffirms that the reduction of social and health inequalities should continue to be a national priority.

Neurocognitive outcome in young adults born late-preterm.

PubMed

Heinonen, Kati; Lahti, Jari; Sammallahti, Sara; Wolke, Dieter; Lano, Aulikki; Andersson, Sture; Pesonen, Anu-Katriina; Eriksson, Johan G; Kajantie, Eero; Raikkonen, Katri

2018-03-01

This study examined whether late-preterm birth (34+0 to 36+6wks+d gestational age) was associated with neurocognitive deficit in young adulthood, and whether small for gestational age (SGA) birth amplified any adversity. Participants derived from the prospective regional cohort study, the Arvo Ylppö Longitudinal Study (n=786; 398 females, 388 males) (mean age 25y 4mo, SD 8mo), born 1985 to 1986 late-preterm (n=119; 21 SGA, <-2 SD) and at term (37+0 to 41+6wks+d; n=667; 28 SGA) underwent tests of intelligence, executive functioning, attention, and memory, and reported their education. Those born late-preterm scored -3.71 (95% confidence interval [CI] -6.71 to -0.72) and -3.11 (95% CI -6.01 to -0.22) points lower on Full-scale and Verbal IQ than peers born at term. Compared with those born at term and appropriate for gestational age (≥-2 to <2 SD) Full-scale, Verbal, and Performance IQ scores of those born late-preterm and SGA were -9.45 to -11.84 points lower. After adjustments, differences were rendered non-significant, except that scores in Full-scale and Performance IQ remained lower among those born late-preterm and SGA. Late-preterm birth, per se, may not increase the risk of poorer neurocognitive functioning in adulthood. But the double burden of being born late-preterm and SGA seems to increase this risk. Late-preterm birth did not increase the risk of poorer neurocognitive functioning in adulthood. But the double burden of being born late-preterm and being small for gestational age did increase this risk. © 2017 Mac Keith Press.

Regional microstructural organization of the cerebral cortex is affected by preterm birth.

PubMed

Bouyssi-Kobar, Marine; Brossard-Racine, Marie; Jacobs, Marni; Murnick, Jonathan; Chang, Taeun; Limperopoulos, Catherine

2018-01-01

To compare regional cerebral cortical microstructural organization between preterm infants at term-equivalent age (TEA) and healthy full-term newborns, and to examine the impact of clinical risk factors on cerebral cortical micro-organization in the preterm cohort. We prospectively enrolled very preterm infants (gestational age (GA) at birth<32 weeks; birthweight<1500 g) and healthy full-term controls. Using non-invasive 3T diffusion tensor imaging (DTI) metrics, we quantified regional micro-organization in ten cerebral cortical areas: medial/dorsolateral prefrontal cortex, anterior/posterior cingulate cortex, insula, posterior parietal cortex, motor/somatosensory/auditory/visual cortex. ANCOVA analyses were performed controlling for sex and postmenstrual age at MRI. We studied 91 preterm infants at TEA and 69 full-term controls. Preterm infants demonstrated significantly higher diffusivity in the prefrontal, parietal, motor, somatosensory, and visual cortices suggesting delayed maturation of these cortical areas. Additionally, postnatal hydrocortisone treatment was related to accelerated microstructural organization in the prefrontal and somatosensory cortices. Preterm birth alters regional microstructural organization of the cerebral cortex in both neurocognitive brain regions and areas with primary sensory/motor functions. We also report for the first time a potential protective effect of postnatal hydrocortisone administration on cerebral cortical development in preterm infants.

Population-wide folic acid fortification and preterm birth: testing the folate depletion hypothesis.

PubMed

Naimi, Ashley I; Auger, Nathalie

2015-04-01

We assess whether population-wide folic acid fortification policies were followed by a reduction of preterm and early-term birth rates in Québec among women with short and optimal interpregnancy intervals. We extracted birth certificate data for 1.3 million births between 1981 and 2010 to compute age-adjusted preterm and early-term birth rates stratified by short and optimal interpregnancy intervals. We used Joinpoint regression to detect changes in the preterm and early term birth rates and assess whether these changes coincide with the implementation of population-wide folic acid fortification. A change in the preterm birth rate occurred in 2000 among women with short (95% confidence interval [CI] = 1994, 2005) and optimal (95% CI = 1995, 2008) interpregnancy intervals. Changes in early term birth rates did not coincide with the implementation of folic acid fortification. Our results do not indicate a link between folic acid fortification and early term birth but suggest an improvement in preterm birth rates after implementation of a nationwide folic acid fortification program.

Prepregnancy Depressive Symptoms and Preterm Birth in the Black Women’s Health Study

PubMed Central

Phillips, Ghasi S.; Wise, Lauren A.; Rich-Edwards, Janet W.; Stampfer, Meir J.; Rosenberg, Lynn

2009-01-01

PURPOSE To examine the association between prepregnancy depressive symptoms and preterm birth. METHODS The present study is a prospective investigation of prepregnancy depressive symptoms—measured by the Center for Epidemiologic Studies Depression Scale (CES-D)—and risk of preterm birth reported in the Black Women’s Health Study. With data on 2,627 singleton births (175 spontaneous and 163 medically-indicated preterm births and 2,289 term births), we used generalized estimating equation models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for potential confounders. RESULTS Relative to mothers with CES-D scores <16, the multivariable ORs of spontaneous preterm birth for mothers with CES-D scores of 16-22, 23-32, and ≥33 were 1.17 (95% CI=0.78-1.80), 1.20 (95% CI=0.69-2.10), and 2.00 (95% CI=0.94-4.25), respectively (P-trend=0.09). There was little evidence of an association between prepregnancy depressive symptoms and medically-indicated preterm birth. CONCLUSIONS Our data provide some evidence of an increased risk of spontaneous preterm birth among women with high prepregnancy depressive symptoms. PMID:20006271

Activity restriction among women with a short cervix.

PubMed

Grobman, William A; Gilbert, Sharon A; Iams, Jay D; Spong, Catherine Y; Saade, George; Mercer, Brian M; Tita, Alan T N; Rouse, Dwight J; Sorokin, Yoram; Leveno, Kenneth J; Tolosa, Jorge E; Thorp, John M; Caritis, Steve N; Van Dorsten, J Peter

2013-06-01

To estimate determinants of and outcomes associated with activity restriction among women with a short cervix. This was a secondary analysis of a randomized trial of 17-α hydroxyprogesterone caproate for prevention of preterm birth among nulliparous women with singleton gestations and cervices less than 30 mm by midtrimester ultrasonography. Women were asked weekly whether they had been placed on pelvic, work, or nonwork rest. "Any activity restriction" was defined as being placed on any type of rest. Factors associated with any activity restriction were determined and the association between preterm birth and activity restriction was estimated with multivariable logistic regression. Of the 657 women in the trial, 646 (98%) responded to questions regarding activity restriction. Two hundred fifty-two (39.0%) were placed on any activity restriction at a median of 23.9 weeks (interquartile range 22.6-27.9 weeks). Women on activity restriction were older, more likely to have private insurance, less likely to be Hispanic, had a shorter cervical length, and were more likely to have funneling and intra-amniotic debris. Preterm birth at less than 37 weeks of gestation was more common among women placed on activity restriction (37% compared with 17%, P<.001). After controlling for potential confounding factors, preterm birth remained more common among those placed on activity restriction (adjusted odds ratio 2.37, 95% confidence interval 1.60-3.53). Results were similar for preterm birth at less than 34 weeks of gestation. Activity restriction did not reduce the rate of preterm birth in asymptomatic nulliparous women with a short cervix.

Activity Restriction Among Women With a Short Cervix

PubMed Central

Grobman, William A.; Gilbert, Sharon A.; Iams, Jay D.; Spong, Catherine Y.; Saade, George; Mercer, Brian M.; Tita, Alan T. N.; Rouse, Dwight J.; Sorokin, Yoram; Leveno, Kenneth J.; Tolosa, Jorge E.; Thorp, John M.; Caritis, Steve N.; Van Dorsten, J. Peter

2014-01-01

OBJECTIVE To estimate determinants of and outcomes associated with activity restriction among women with a short cervix. METHODS This was a secondary analysis of a randomized trial of 17-α hydroxyprogesterone caproate for prevention of preterm birth among nulliparous women with singleton gestations and cervices less than 30 mm by midtrimester ultrasonography. Women were asked weekly whether they had been placed on pelvic, work, or nonwork rest. “Any activity restriction” was defined as being placed on any type of rest. Factors associated with any activity restriction were determined and the association between preterm birth and activity restriction was estimated with multivariable logistic regression. RESULTS Of the 657 women in the trial, 646 (98%) responded to questions regarding activity restriction. Two hundred fifty-two (39.0%) were placed on any activity restriction at a median of 23.9 weeks (interquartile range 22.6–27.9 weeks).Women on activity restriction were older, more likely to have private insurance, less likely to be Hispanic, had a shorter cervical length, and were more likely to have funneling and intra-amniotic debris. Preterm birth at less than 37 weeks of gestation was more common among women placed on activity restriction (37% compared with 17%, P<.001). After controlling for potential confounding factors, preterm birth remained more common among those placed on activity restriction (adjusted odds ratio 2.37, 95% confidence interval 1.60–3.53). Results were similar for preterm birth at less than 34 weeks of gestation. CONCLUSION Activity restriction did not reduce the rate of preterm birth in asymptomatic nulliparous women with a short cervix. PMID:23812450

Overweight and obesity in mothers and risk of preterm birth and low birth weight infants: systematic review and meta-analyses.

PubMed

McDonald, Sarah D; Han, Zhen; Mulla, Sohail; Beyene, Joseph

2010-07-20

To determine the relation between overweight and obesity in mothers and preterm birth and low birth weight in singleton pregnancies in developed and developing countries. Systematic review and meta-analyses. Medline and Embase from their inceptions, and reference lists of identified articles. Studies including a reference group of women with normal body mass index that assessed the effect of overweight and obesity on two primary outcomes: preterm birth (before 37 weeks) and low birth weight (<2500 g). Two assessors independently reviewed titles, abstracts, and full articles, extracted data using a piloted data collection form, and assessed quality. 84 studies (64 cohort and 20 case-control) were included, totalling 1 095 834 women. Although the overall risk of preterm birth was similar in overweight and obese women and women of normal weight, the risk of induced preterm birth was increased in overweight and obese women (relative risk 1.30, 95% confidence interval 1.23 to 1.37). Although overall the risk of having an infant of low birth weight was decreased in overweight and obese women (0.84, 0.75 to 0.95), the decrease was greater in developing countries than in developed countries (0.58, 0.47 to 0.71 v 0.90, 0.79 to 1.01). After accounting for publication bias, the apparent protective effect of overweight and obesity on low birth weight disappeared with the addition of imputed "missing" studies (0.95, 0.85 to 1.07), whereas the risk of preterm birth appeared significantly higher in overweight and obese women (1.24, 1.13 to 1.37). Overweight and obese women have increased risks of preterm birth and induced preterm birth and, after accounting for publication bias, appeared to have increased risks of preterm birth overall. The beneficial effects of maternal overweight and obesity on low birth weight were greater in developing countries and disappeared after accounting for publication bias.

Outcomes and predictive tests from a dedicated specialist clinic for women at high risk of preterm labour: A ten year audit.

PubMed

Hughes, Kelly; Sim, Shirlene; Roman, Alina; Michalak, Kasia; Kane, Stefan; Sheehan, Penelope

2017-08-01

Preterm birth continues to be a major cause of infant morbidity and mortality worldwide, but advances have recently been made in its prediction and prevention. A short cervix (<25 mm) in the second trimester on transvaginal ultrasound scan and fetal fibronectin are important predictive tests. For over ten years, the Preterm Labour Clinic at the Royal Women's Hospital, Melbourne, Australia has provided care for women at high risk of preterm birth, including those with a previous preterm birth, previous cervical surgery, uterine malformation or incidental finding of short cervix at routine ultrasound. The purpose of this study was to review this clinic's outcomes for the first decade. This was a retrospective cohort study of all referrals to the Preterm Labour Clinic during the period 2004-2013 inclusive. Seven hundred and fifty-six cases met the study inclusion criteria of appropriate risk factor, singleton pregnancy, surveillance undertaken and outcome data available. The preterm birth rate (<37 weeks) was 21.4%. The rate of preterm birth by year decreased significantly when adjusted for risk (P = 0.002). A short cervix was diagnosed in 32% of the sample, and positively correlated with lower gestational age at delivery. Fetal fibronectin and serum alkaline phosphatase were independent predictors of preterm birth <34 weeks and <37 weeks. The adjusted preterm birth rate at the Royal Women's Hospital's Preterm Labour Clinic has decreased significantly over the decade studied. Positive fetal fibronectin at 26 weeks and elevated serum alkaline phosphatase are independent predictors of preterm birth. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Effect of maternal age on the risk of preterm birth: A large cohort study

PubMed Central

Monet, Barbara; Ducruet, Thierry; Chaillet, Nils; Audibert, Francois

2018-01-01

Background Maternal age at pregnancy is increasing worldwide as well as preterm birth. However, the association between prematurity and advanced maternal age remains controversial. Objective To evaluate the impact of maternal age on the occurrence of preterm birth after controlling for multiple known confounders in a large birth cohort. Study design Retrospective cohort study using data from the QUARISMA study, a large Canadian randomized controlled trial, which collected data from 184,000 births in 32 hospitals. Inclusion criteria were maternal age over 20 years. Exclusion criteria were multiple pregnancy, fetal malformation and intra-uterine fetal death. Five maternal age categories were defined and compared for maternal characteristics, gestational and obstetric complications, and risk factors for prematurity. Risk factors for preterm birth <37 weeks, either spontaneous or iatrogenic, were evaluated for different age groups using multivariate logistic regression. Results 165,282 births were included in the study. Chronic hypertension, assisted reproduction techniques, pre-gestational diabetes, invasive procedure in pregnancy, gestational diabetes and placenta praevia were linearly associated with increasing maternal age whereas hypertensive disorders of pregnancy followed a “U” shaped distribution according to maternal age. Crude rates of preterm birth before 37 weeks followed a “U” shaped curve with a nadir at 5.7% for the group of 30–34 years. In multivariate analysis, the adjusted odds ratio (aOR) of prematurity stratified by age group followed a “U” shaped distribution with an aOR of 1.08 (95%CI; 1.01–1.15) for 20–24 years, and 1.20 (95% CI; 1.06–1.36) for 40 years and older. Confounders found to have the greatest impact were placenta praevia, hypertensive complications, and maternal medical history. Conclusion Even after adjustment for confounders, advanced maternal age (40 years and over) was associated with preterm birth. A maternal age of 30–34 years was associated with the lowest risk of prematurity. PMID:29385154

Effect of maternal age on the risk of preterm birth: A large cohort study.

PubMed

Fuchs, Florent; Monet, Barbara; Ducruet, Thierry; Chaillet, Nils; Audibert, Francois

2018-01-01

Maternal age at pregnancy is increasing worldwide as well as preterm birth. However, the association between prematurity and advanced maternal age remains controversial. To evaluate the impact of maternal age on the occurrence of preterm birth after controlling for multiple known confounders in a large birth cohort. Retrospective cohort study using data from the QUARISMA study, a large Canadian randomized controlled trial, which collected data from 184,000 births in 32 hospitals. Inclusion criteria were maternal age over 20 years. Exclusion criteria were multiple pregnancy, fetal malformation and intra-uterine fetal death. Five maternal age categories were defined and compared for maternal characteristics, gestational and obstetric complications, and risk factors for prematurity. Risk factors for preterm birth <37 weeks, either spontaneous or iatrogenic, were evaluated for different age groups using multivariate logistic regression. 165,282 births were included in the study. Chronic hypertension, assisted reproduction techniques, pre-gestational diabetes, invasive procedure in pregnancy, gestational diabetes and placenta praevia were linearly associated with increasing maternal age whereas hypertensive disorders of pregnancy followed a "U" shaped distribution according to maternal age. Crude rates of preterm birth before 37 weeks followed a "U" shaped curve with a nadir at 5.7% for the group of 30-34 years. In multivariate analysis, the adjusted odds ratio (aOR) of prematurity stratified by age group followed a "U" shaped distribution with an aOR of 1.08 (95%CI; 1.01-1.15) for 20-24 years, and 1.20 (95% CI; 1.06-1.36) for 40 years and older. Confounders found to have the greatest impact were placenta praevia, hypertensive complications, and maternal medical history. Even after adjustment for confounders, advanced maternal age (40 years and over) was associated with preterm birth. A maternal age of 30-34 years was associated with the lowest risk of prematurity.

Sources of fine particulate matter and risk of preterm birth in Connecticut, 2000-2006: a longitudinal study.

PubMed

Pereira, Gavin; Bell, Michelle L; Lee, Hyung Joo; Koutrakis, Petros; Belanger, Kathleen

2014-10-01

Previous studies have examined fine particulate matter (≤ 2.5 μm; PM2.5) and preterm birth, but there is a dearth of longitudinal studies on this topic and a paucity of studies that have investigated specific sources of this exposure. Our aim was to assess whether anthropogenic sources are associated with risk of preterm birth, comparing successive pregnancies to the same woman. Birth certificates were used to select women who had vaginal singleton live births at least twice in Connecticut during 2000-2006 (n = 23,123 women, n = 48,208 births). We procured 4,085 daily samples of PM2.5 on Teflon filters from the Connecticut Department of Environmental Protection for six cities in Connecticut. Filters were analyzed for chemical composition, and Positive Matrix Factorization was used to determine contributions of PM2.5 sources. Risk estimates were calculated with conditional logistic regression, matching pregnancies to the same women. Odds ratios of preterm birth per interquartile range increase in whole pregnancy exposure to dust, motor vehicle emissions, oil combustion, and regional sulfur PM2.5 sources were 1.01 (95% CI: 0.93, 1.09), 1.01 (95% CI: 0.92, 1.10), 1.00 (95% CI: 0.89, 1.12), and 1.09 (95% CI: 0.97, 1.22), respectively. This was the first study of PM2.5 sources and preterm birth, and the first matched analysis, that better addresses individual-level confounding potentially inherent in all past studies. There was insufficient evidence to suggest that sources were statistically significantly associated with preterm birth. However, elevated central estimates and previously observed associations with mass concentration motivate the need for further research. Future studies would benefit from high source exposure settings and longitudinal study designs, such as that adopted in this study.

Birth outcomes associated with receipt of group prenatal care among low-income Hispanic women.

PubMed

Tandon, S Darius; Colon, Lucinda; Vega, Patricia; Murphy, Jeanne; Alonso, Alina

2012-01-01

Although Hispanic women in the United States have preterm birth and low-birth-weight rates comparable to non-Hispanic white women, their rates fall short of 2010 Healthy People goals, with variability found across states. This study examined the effectiveness of the CenteringPregnancy group prenatal care model in reducing preterm birth and low-birth-weight rates for Hispanic women. Pregnant Hispanic women at less than or equal to 20 weeks, gestation initiating prenatal care between January 2008 to July 2009 at 2 Palm Beach County, Florida, public health clinics selected either group or traditional prenatal care. Data on neonatal birth weight and gestational age were obtained through abstraction of Palm Beach County Health Department medical records. Records were abstracted for 97% of CenteringPregnancy (n = 150) and 94% of traditional care (n = 66) participants. A statistically significant difference was found in the percentage of women giving birth to preterm neonates (5% group prenatal care vs 13% traditional care; P= .04). There were no statistically significant differences in the percentage of women having a low-birth-weight neonate when group and traditional care participants were compared. The CenteringPregnancy model holds promise for improving the birth outcomes of Hispanic women. Future research should be conducted with larger sample sizes to replicate study findings using experimental designs and incorporating formal cost-effectiveness analyses. © 2012 by the American College of Nurse-Midwives.

Visual Cortical Function in Very Low Birth Weight Infants without Retinal or Cerebral Pathology

PubMed Central

Hou, Chuan; Norcia, Anthony M.; Madan, Ashima; Tith, Solina; Agarwal, Rashi

2011-01-01

Purpose. Preterm infants are at high risk of visual and neural developmental deficits. However, the development of visual cortical function in preterm infants with no retinal or neurologic morbidity has not been well defined. To determine whether premature birth itself alters visual cortical function, swept parameter visual evoked potential (sVEP) responses of healthy preterm infants were compared with those of term infants. Methods. Fifty-two term infants and 58 very low birth weight (VLBW) infants without significant retinopathy of prematurity or neurologic morbidities were enrolled. Recruited VLBW infants were between 26 and 33 weeks of gestational age, with birth weights of less than 1500 g. Spatial frequency, contrast, and vernier offset sweep VEP tuning functions were measured at 5 to 7 months' corrected age. Acuity and contrast thresholds were derived by extrapolating the tuning functions to 0 amplitude. These thresholds and suprathreshold response amplitudes were compared between groups. Results. Preterm infants showed increased thresholds (indicating decreased sensitivity to visual stimuli) and reductions in amplitudes for all three measures. These changes in cortical responsiveness were larger in the <30 weeks ' gestational age subgroup than in the ≥30 weeks' gestational age subgroup. Conclusions. Preterm infants with VLBW had measurable and significant changes in cortical responsiveness that were correlated with gestational age. These results suggest that premature birth in the absence of identifiable retinal or neurologic abnormalities has a significant effect on visual cortical sensitivity at 5 to 7 months' of corrected age and that gestational age is an important factor in visual development. PMID:22025567

Maternal early pregnancy body mass index and risk of preterm birth.

PubMed

Wang, Ting; Zhang, Jun; Lu, Xinrong; Xi, Wei; Li, Zhu

2011-10-01

To determine the association between maternal body mass index (BMI) in early pregnancy and the risk of preterm birth (PTB) in Chinese women. Data were obtained from a population-based perinatal care program in China during 1993-2005. Women whose height and weight information was recorded at the first prenatal visit in the first trimester of pregnancy and delivered a singleton live infant were selected. Women with multiple gestations, stillbirths, delivery before 28 weeks or after 44 weeks of gestation, and infants affected by major external birth defects were excluded. BMI was categorized as underweight (less than 18.5 kg/m(2)), normal weight (18.5-23.9 kg/m(2)), overweight (24-27.9 kg/m(2)), and obese (≥28 kg/m(2)) based on BMI classification criteria for Chinese. Logistic regression analysis was conducted to adjust for potential confounders, such as maternal age, education, occupation, city or county, gender of infant, and year of delivery. A total of 353,477 women were selected. The incidence of preterm birth in women who were underweight, normal weight, overweight, obese was 3.69% (3.61-3.76%), 3.59% (3.55-3.62%), 3.83% (3.71-3.96%), 4.90% (4.37-5.43%), respectively. The incidence of elective preterm birth, overweight, and obesity increased remarkably during 2000-2005 compared with that during 1993-1996. After having adjusted for potential confounders including maternal age, maternal occupation, education, city or county, gender of the infant and year of birth, the risk of PTB increased significantly with BMI (P < 0.05). Among nulliparae, the risk of elective preterm birth increased with increasing BMI. Nulliparae who were underweight were less likely to deliver elective preterm births (OR = 0.89, 95% CI 0.80-0.98). Nulliparae who were overweight and obese in early pregnancy were at a greater risk of elective PTB than normal weight nulliparae (for the overweight OR = 1.36, 95% CI 1.18-1.56, for the obese OR = 2.94, 95% CI 2.04-4.25). In this study, indigenous Chinese cohort women who are overweight, obese, and nulliparous are at an increased risk of elective preterm birth.

Maternal Dietary Patterns during the Second Trimester Are Associated with Preterm Birth123

PubMed Central

Martin, Chantel L; Sotres-Alvarez, Daniela; Siega-Riz, Anna Maria

2015-01-01

Background: Preterm birth is one of the leading causes of neonatal morbidity in the United States. Despite decades of research, the etiology is largely unknown. Objective: The purpose of our study was to examine the association between maternal dietary patterns during pregnancy and preterm birth. Methods: This prospective cohort study used data from the PIN (Pregnancy, Infection, and Nutrition) study (n = 3143). Dietary intake was assessed at 26–29 wk of gestation by using a food-frequency questionnaire, and patterns were derived by using factor analysis and the Dietary Approaches to Stop Hypertension (DASH) diet. Associations between dietary patterns and preterm birth were assessed by logistic regression. Results: Four dietary patterns were identified from the factor analysis characterized by high intakes of the following: 1) fruits, vegetables, low-fat dairy, high-fiber and fortified cereals, nonfried chicken and fish, and wheat bread; 2) beans, corn, French fries, hamburgers or cheeseburgers, white potatoes, fried chicken, mixed dishes, and ice cream; 3) collard greens, coleslaw or cabbage, red and processed meats, cornbread or hushpuppies, whole milk, and vitamin C–rich drinks; and 4) shellfish, pizza, salty snacks, and refined grains. Increased odds of preterm birth were found for a diet characterized by a high consumption of collard greens, coleslaw or cabbage, red meats, fried chicken and fish, processed meats, cornbread or hushpuppies, eggs or egg biscuits, gravy, whole milk, and vitamin C–rich drinks such as Kool-Aid (Kraft Foods) and Hi-C (Minute Maid Co.) (adjusted OR for quartile 4 vs. quartile 1: 1.55; 95% CI: 1.07, 2.24). Greater adherence to the DASH diet was associated with decreased odds of preterm birth compared with women in the lowest quartile (adjusted OR for quartile 4 vs. quartile 1: 0.59; 95% CI: 0.40, 0.85). Conclusions: Diet quality during pregnancy is associated with preterm birth; thus, preconceptional and early prenatal dietary counseling promoting healthy dietary intake could improve pregnancy outcomes. PMID:26084362

Maternal Dietary Patterns during the Second Trimester Are Associated with Preterm Birth.

PubMed

Martin, Chantel L; Sotres-Alvarez, Daniela; Siega-Riz, Anna Maria

2015-08-01

Preterm birth is one of the leading causes of neonatal morbidity in the United States. Despite decades of research, the etiology is largely unknown. The purpose of our study was to examine the association between maternal dietary patterns during pregnancy and preterm birth. This prospective cohort study used data from the PIN (Pregnancy, Infection, and Nutrition) study (n = 3143). Dietary intake was assessed at 26-29 wk of gestation by using a food-frequency questionnaire, and patterns were derived by using factor analysis and the Dietary Approaches to Stop Hypertension (DASH) diet. Associations between dietary patterns and preterm birth were assessed by logistic regression. Four dietary patterns were identified from the factor analysis characterized by high intakes of the following: 1) fruits, vegetables, low-fat dairy, high-fiber and fortified cereals, nonfried chicken and fish, and wheat bread; 2) beans, corn, French fries, hamburgers or cheeseburgers, white potatoes, fried chicken, mixed dishes, and ice cream; 3) collard greens, coleslaw or cabbage, red and processed meats, cornbread or hushpuppies, whole milk, and vitamin C-rich drinks; and 4) shellfish, pizza, salty snacks, and refined grains. Increased odds of preterm birth were found for a diet characterized by a high consumption of collard greens, coleslaw or cabbage, red meats, fried chicken and fish, processed meats, cornbread or hushpuppies, eggs or egg biscuits, gravy, whole milk, and vitamin C-rich drinks such as Kool-Aid (Kraft Foods) and Hi-C (Minute Maid Co.) (adjusted OR for quartile 4 vs. quartile 1: 1.55; 95% CI: 1.07, 2.24). Greater adherence to the DASH diet was associated with decreased odds of preterm birth compared with women in the lowest quartile (adjusted OR for quartile 4 vs. quartile 1: 0.59; 95% CI: 0.40, 0.85). Diet quality during pregnancy is associated with preterm birth; thus, preconceptional and early prenatal dietary counseling promoting healthy dietary intake could improve pregnancy outcomes. © 2015 American Society for Nutrition.

Evaluation of Syracuse Healthy Start's program for abnormal flora management to reduce preterm birth among pregnant women.

PubMed

Koumans, Emilia H; Lane, Sandra D; Aubry, Richard; Demott, Kathleen; Webster, Noah; Levandowski, Brooke A; Berman, Stuart; Markowitz, Lauri E

2011-10-01

Randomized trials of bacterial vaginosis (BV) treatment among pregnant women to reduce preterm birth have had mixed results. Among non-pregnant women, BV recurs frequently after treatment. Randomized trials of early BV treatment for pregnant women in which recurrence was retreated have shown promise in reducing preterm birth. Syracuse's Healthy Start (SHS) program began in 1997; in 1998 prenatal care providers for pregnant women living in high infant mortality zip codes were encouraged to screen for abnormal vaginal flora at the first prenatal visit. Vaginal swabs were sent to a referral hospital laboratory for Gram staining and interpretation. SHS encouraged providers to treat and rescreen women with bacterial vaginosis or abnormal flora (BV). We abstracted prenatal and hospital charts of live births between January 2000 and March 2002 for maternal conditions and treatments. We merged abstracted data with local electronic data. We evaluated the effect of BV screening before 22 weeks gestation, treatment, and rescreening using a retrospective cohort study design. Among 838 women first screened before 22 weeks, 346 (41%) had normal flora and 492 (59%) women had BV at a mean of 13 weeks gestation; 202 (24%) did not have treatment documented and 290 (35%) received treatment at a mean of 15 weeks gestation; 267 (92%) of those treated were re-screened. Among pregnant women with early BV, 42 (21%) untreated women and 28 (10%) treated women delivered preterm (Odds Ratio [OR] 0.4, 95% confidence interval [CI] 0.2-0.7)). After adjustment for age, race, prior preterm birth and other possible confounders, treatment remained associated with a reduced risk of preterm birth compared to no treatment (aOR = 0.5, 95% CI 0.3-0.9); the aOR for women with normal flora was not significantly different. Screening, treatment, and rescreening for BV/abnormal flora between the first prenatal visit and 22 weeks gestation showed promise in reducing preterm births and deserves further study.

The role of progesterone in prevention of preterm birth

PubMed Central

Dodd, Jodie M; Crowther, Caroline A

2010-01-01

Preterm birth continues to provide an enormous challenge in the delivery of perinatal health care, and is associated with considerable short and long-term health consequences for surviving infants. Progesterone has a role in maintaining pregnancy, by suppression of the calcium–calmodulin–myosin light chain kinase system. Additionally, progesterone has recognized anti-inflammatory properties, raising a possible link between inflammatory processes, alterations in progesterone receptor expression and the onset of preterm labor. Systematic reviews of randomized controlled trials evaluating the use of intramuscular and vaginal progesterone in women considered to be at increased risk of preterm birth have been published, with primary outcomes of perinatal death, preterm birth <34 weeks, and neurodevelopmental handicap in childhood. Eleven randomized controlled trials were included in the systematic review, involving 2714 women and 3452 infants, with results presented according to the reason women were considered to be at increased risk of preterm birth. While there is a potential beneficial effect in the use of progesterone for some women considered to be at increased risk of preterm birth, primarily in the reduction in the risk of preterm birth before 34 weeks gestation, it remains unclear if the observed prolongation of pregnancy translates into improved health outcomes for the infant. PMID:21072277

Modeling the Cost-Effectiveness of Doula Care Associated with Reductions in Preterm Birth and Cesarean Delivery.

PubMed

Kozhimannil, Katy B; Hardeman, Rachel R; Alarid-Escudero, Fernando; Vogelsang, Carrie A; Blauer-Peterson, Cori; Howell, Elizabeth A

2016-03-01

One in nine US infants is born before 37 weeks' gestation, incurring medical costs 10 times higher than full-term infants. One in three infants is born by cesarean; cesarean births cost twice as much as vaginal births. We compared rates of preterm and cesarean birth among Medicaid recipients with prenatal access to doula care (nonmedical maternal support) with similar women regionally. We used data on this association to mathematically model the potential cost-effectiveness of Medicaid coverage of doula services. Data came from two sources: all Medicaid-funded, singleton births at hospitals in the West North Central and East North Central US (n = 65,147) in the 2012 Nationwide Inpatient Sample, and all Medicaid-funded singleton births (n = 1,935) supported by a community-based doula organization in the Upper Midwest from 2010 to 2014. We analyzed routinely collected, de-identified administrative data. Multivariable regression analysis was used to estimate associations between doula care and outcomes. A probabilistic decision-analytic model was used for cost-effectiveness estimates. Women who received doula support had lower preterm and cesarean birth rates than Medicaid beneficiaries regionally (4.7 vs 6.3%, and 20.4 vs 34.2%). After adjustment for covariates, women with doula care had 22 percent lower odds of preterm birth (AOR 0.77 [95% CI 0.61-0.96]). Cost-effectiveness analyses indicate potential savings associated with doula support reimbursed at an average of $986 (ranging from $929 to $1,047 across states). Based on associations between doula care and preterm and cesarean birth, coverage reimbursement for doula services would likely be cost saving or cost-effective for state Medicaid programs. © 2016 Wiley Periodicals, Inc.

Modeling the cost effectiveness of doula care associated with reductions in preterm birth and cesarean delivery

PubMed Central

Kozhimannil, Katy B; Hardeman, Rachel R.; Alarid-Escudero, Fernando; Vogelsang, Carrie; Blauer-Peterson, Cori; Howell, Elizabeth A.

2017-01-01

Background One in nine US infants is born before 37 weeks gestation, incurring medical costs 10 times higher than full-term infants. One in three infants is born by cesarean; cesarean births cost twice as much as vaginal births. We compared rates of preterm and cesarean birth among Medicaid recipients with prenatal access to doula care (non-medical maternal support) with similar women regionally. We used data on this association to mathematically model the potential cost effectiveness of Medicaid coverage of doula services. Methods Data came from two sources: all Medicaid-funded, singleton births at hospitals in the West North Central and East North Central US (n=65,147) in the 2012 Nationwide Inpatient Sample, and all Medicaid-funded singleton births (n=1,935) supported by a community-based doula organization in the Upper Midwest from 2010–2014. We analyzed routinely collected, de-identified administrative data. Multivariable regression analysis was used to estimate associations between doula care and outcomes. A probabilistic decision-analytic model was used for cost-effectiveness estimates. Results Women who received doula support had lower preterm and cesarean birth rates than Medicaid beneficiaries regionally (4.7% vs. 6.3%, and 20.4% vs. 34.2%). After adjustment for covariates, women with doula care had 22% lower odds of preterm birth (AOR=0.77, 95% CI[0.61–0.96]). Cost-effectiveness analyses indicate potential savings associated with doula support reimbursed at an average of $986, (ranging from $929 to $1,047 across states). Conclusions Based on associations between doula care and preterm and cesarean birth, coverage reimbursement for doula services would likely be cost saving or cost effective for state Medicaid programs. PMID:26762249

Air pollution, inflammation and preterm birth: a potential mechanistic link.

PubMed

Vadillo-Ortega, Felipe; Osornio-Vargas, Alvaro; Buxton, Miatta A; Sánchez, Brisa N; Rojas-Bracho, Leonora; Viveros-Alcaráz, Martin; Castillo-Castrejón, Marisol; Beltrán-Montoya, Jorge; Brown, Daniel G; O'Neill, Marie S

2014-02-01

Preterm birth is a public health issue of global significance, which may result in mortality during the perinatal period or may lead to major health and financial consequences due to lifelong impacts. Even though several risk factors for preterm birth have been identified, prevention efforts have failed to halt the increasing rates of preterm birth. Epidemiological studies have identified air pollution as an emerging potential risk factor for preterm birth. However, many studies were limited by study design and inadequate exposure assessment. Due to the ubiquitous nature of ambient air pollution and the potential public health significance of any role in causing preterm birth, a novel focus investigating possible causal mechanisms influenced by air pollution is therefore a global health priority. We hypothesize that air pollution may act together with other biological factors to induce systemic inflammation and influence the duration of pregnancy. Evaluation and testing of this hypothesis is currently being conducted in a prospective cohort study in Mexico City and will provide an understanding of the pathways that mediate the effects of air pollution on preterm birth. The important public health implication is that crucial steps in this mechanistic pathway can potentially be acted on early in pregnancy to reduce the risk of preterm birth. Copyright © 2013 Elsevier Ltd. All rights reserved.

AIR POLLUTION, INFLAMMATION AND PRETERM BIRTH: A POTENTIAL MECHANISTIC LINK

PubMed Central

Vadillo-Ortega, Felipe; Osornio-Vargas, Alvaro; Buxton, Miatta A.; Sánchez, Brisa N.; Rojas-Bracho, Leonora; Viveros-Alcaráz, Martin; Castillo-Castrejón, Marisol; Beltrán-Montoya, Jorge; Brown, Daniel G.; O´Neill, Marie S.

2014-01-01

Preterm birth is a public health issue of global significance, which may result in mortality during the perinatal period or may lead to major health and financial consequences due to lifelong impacts. Even though several risk factors for preterm birth have been identified, prevention efforts have failed to halt the increasing rates of preterm birth. Epidemiological studies have identified air pollution as an emerging potential risk factor for preterm birth. However, many studies were limited by study design and inadequate exposure assessment. Due to the ubiquitous nature of ambient air pollution and the potential public health significance of any role in causing preterm birth, a novel focus investigating possible causal mechanisms influenced by air pollution is therefore a global health priority. We hypothesize that air pollution may act together with other biological factors to induce systemic inflammation and influence the duration of pregnancy. Evaluation and testing of this hypothesis is currently being conducted in a prospective cohort study in Mexico City and will provide an understanding of the pathways that mediate the effects of air pollution on preterm birth. The important public health implication is that crucial steps in this mechanistic pathway can potentially be acted on early in pregnancy to reduce the risk of preterm birth. PMID:24382337

Residential Agricultural Pesticide Exposures and Risks of Spontaneous Preterm Birth.

PubMed

Shaw, Gary M; Yang, Wei; Roberts, Eric M; Kegley, Susan E; Stevenson, David K; Carmichael, Suzan L; English, Paul B

2018-01-01

Pesticides exposures are aspects of the human exposome that have not been sufficiently studied for their contribution to risk for preterm birth. We investigated risks of spontaneous preterm birth from potential residential exposures to 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. After exclusions, the analytic study base included 197,461 term control births and 27,913 preterm case births. Preterm cases were more narrowly defined as 20-23 weeks (n = 515), 24-27 weeks (n = 1,792), 28-31 weeks (n = 3,098), or 32-36 weeks (n = 22,508). The frequency of any (versus none) pesticide exposure was uniformly lower in each preterm case group relative to the frequency in term controls, irrespective of gestational month of exposure. All odds ratios were below 1.0 for these any versus no exposure comparisons. The majority of odds ratios were below 1.0, many of them statistically precise, for preterm birth and exposures to specific chemical groups or chemicals. This study showed a general lack of increased risk of preterm birth associated with a range of agriculture pesticide exposures near women's residences.

Early discharge with tube feeding at home for preterm infants is associated with longer duration of breast feeding.

PubMed

Meerlo-Habing, Z E; Kosters-Boes, E A; Klip, H; Brand, P L P

2009-07-01

Mothers of preterm infants are more likely to discontinue breast feeding early than mothers of term infants. We evaluated the effect of early discharge with tube feeding of preterm infants under close supervision by paediatric nurse specialists on the duration of breast feeding. Case-control study. Medium/high-care neonatal unit of a large district general hospital. Preterm infants (<37 weeks' gestational age). Early discharge with tube feeding under close supervision by paediatric nurse specialists or regular follow-up of preterm infants discharged with oral feeding. Duration of breast feeding assessed by telephone interview 6 months after birth. There were 50 preterm infants in the early discharge group and 78 in the control group. Mothers in the early discharge group continued to breast feed longer than mothers in the control group (log rank test, p = 0.028). Four months after discharge, 63% of preterm infants in the control group were fed formula compared to 36% in the early discharge group (95% CI for difference 9% to 43%, p = 0.04). The relative risk of breast feeding cessation 6 months after birth in the early discharge group compared to the control group was 0.63 (95% CI 0.41 to 0.96). After adjustment for smoking, gestational age and birth weight, this relative risk was 0.67 (95% CI 0.43 to 1.05). Close supervision and follow-up by paediatric nurse specialists of preterm infants discharged early with tube feeding appears to increase duration of breast feeding. A randomised controlled trial to confirm these findings is warranted.

Time trends and risk factor associated with premature birth and infants deaths due to prematurity in Hubei Province, China from 2001 to 2012.

PubMed

Xu, Haiqing; Dai, Qiong; Xu, Yusong; Gong, Zhengtao; Dai, Guohong; Ding, Ming; Duggan, Christopher; Hu, Zubin; Hu, Frank B

2015-12-10

The nutrition and epidemiologic transition has been associated with an increasing incidence of preterm birth in developing countries, but data from large observational studies in China have been limited. Our study was to describe the trends and factors associated with the incidence of preterm birth and infant mortality due to prematurity in Hubei Province, China. We conducted a population-based survey through the Maternal and Child Health Care Network in Hubei Province from January 2001 to December 2012. We used data from 16 monitoring sites to examine the trend and risk factors for premature birth as well as infant mortality associated with prematurity. A total of 818,481 live births were documented, including 76,923 preterm infants (94 preterm infants per 1,000 live births) and 2,248 deaths due to prematurity (2.75 preterm deaths per 1,000 live births). From 2001 to 2012, the incidence of preterm birth increased from 56.7 to 105.2 per 1,000 live births (P for trend < 0.05), while the infant mortality rate due to prematurity declined from 95.0 to 13.4 per 1,000 live births (P for trend < 0.05). Older maternal age, lower maternal education, use of assisted reproductive technology (ART), higher income, residence in urban areas, and infant male sex were independently associated with a higher incidence of preterm birth (all p values < 0.05). Shorter gestation, lower birth weight, and lower income were associated with a higher mortality rate, while use of newborn emergency transport services (NETS) was associated with a lower preterm mortality rate (all p values < 0.05). An increasing incidence of preterm birth and a parallel reduction in infant mortality due to prematurity were observed in Hubei Province from 2001 to 2012. Our results provide important information for areas of improvements in reducing incidence and mortality of premature birth.

Cost consequences of induced abortion as an attributable risk for preterm birth and impact on informed consent.

PubMed

Calhoun, Byron C; Shadigian, Elizabeth; Rooney, Brent

2007-10-01

To investigate the human and monetary cost consequences of preterm delivery as related to induced abortion (IA), with its impact on informed consent and medical malpractice. A review of the literature in English was performed to assess the effect of IA on preterm delivery rates from 24 to 31 6/7 weeks to assess the risk for preterm birth attributable to IA. After calculating preterm birth risk, the increased initial neonatal hospital costs and cerebral palsy (CP) risks related to IA were calculated. IA increased the early preterm delivery rate by 31.5%, with a yearly increase in initial neonatal hospital costs related to IA of > $1.2 billion. The yearly human cost includes 22,917 excess early preterm births (EPB) (< 32 weeks) and 1096 excess CP cases in very-low-birth-weight newborns, <1500 g. IA contributes to significantly increased neonatal health costs by causing 31.5% of EPB. Providers of obstetric care and abortion should be aware of the risk of preterm birth attributable to induced abortion, with its significant increase in initial neonatal hospital costs and CP cases.

Variations in Multiple Birth Rates and Impact on Perinatal Outcomes in Europe

PubMed Central

Heino, Anna; Gissler, Mika; Hindori-Mohangoo, Ashna D.; Blondel, Béatrice; Klungsøyr, Kari; Verdenik, Ivan; Mierzejewska, Ewa; Velebil, Petr; Sól Ólafsdóttir, Helga; Macfarlane, Alison; Zeitlin, Jennifer

2016-01-01

Objective Infants from multiple pregnancies have higher rates of preterm birth, stillbirth and neonatal death and differences in multiple birth rates (MBR) exist between countries. We aimed to describe differences in MBR in Europe and to investigate the impact of these differences on adverse perinatal outcomes at a population level. Methods We used national aggregate birth data on multiple pregnancies, maternal age, gestational age (GA), stillbirth and neonatal death collected in the Euro-Peristat project (29 countries in 2010, N = 5 074 643 births). We also used European Society of Human Reproduction and Embryology (ESHRE) data on assisted conception and single embryo transfer (SET). The impact of MBR on outcomes was studied using meta-analysis techniques with random-effects models to derive pooled risk ratios (pRR) overall and for four groups of country defined by their MBR. We computed population attributable risks (PAR) for these groups. Results In 2010, the average MBR was 16.8 per 1000 women giving birth, ranging from 9.1 (Romania) to 26.5 (Cyprus). Compared to singletons, multiples had a nine-fold increased risk (pRR 9.4, 95% Cl 9.1–9.8) of preterm birth (<37 weeks GA), an almost 12-fold increased risk (pRR 11.7, 95% CI 11.0–12.4) of very preterm birth (<32 weeks GA). Pooled RR were 2.4 (95% Cl 1.5–3.6) for fetal mortality at or after 28 weeks GA and 7.0 (95% Cl 6.1–8.0) for neonatal mortality. PAR of neonatal death and very preterm birth were higher in countries with high MBR compared to low MBR (17.1% (95% CI 13.8–20.2) versus 9.8% (95% Cl 9.6–11.0) for neonatal death and 29.6% (96% CI 28.5–30.6) versus 17.5% (95% CI 15.7–18.3) for very preterm births, respectively). Conclusions Wide variations in MBR and their impact on population outcomes imply that efforts by countries to reduce MBR could improve perinatal outcomes, enabling better long-term child health. PMID:26930069

Thyroperoxidase and thyroglobulin antibodies in early pregnancy and preterm delivery.

PubMed

Haddow, James E; Cleary-Goldman, Jane; McClain, Monica R; Palomaki, Glenn E; Neveux, Louis M; Lambert-Messerlian, Geralyn; Canick, Jacob A; Malone, Fergal D; Porter, T Flint; Nyberg, David A; Bernstein, Peter S; D'Alton, Mary E

2010-07-01

To further evaluate the relationship between thyroid antibodies and preterm births. This is a prospective study of pregnancy outcome and demographic data combined with retrospective measurement of thyroperoxidase and thyroglobulin antibodies. Sera were obtained at 11-13 and 15-18 weeks of gestation from 10,062 women with singleton viable pregnancies (a subset from the First- and Second-Trimester Risk of Aneuploidy [FaSTER] trial). Women with elevated levels of thyroperoxidase, thyroglobulin antibodies, or both in the first trimester have a higher rate of preterm delivery before 37 weeks of gestation than antibody-negative women (7.5% compared with 6.4%, odds ratio [OR] 1.18; 95% confidence interval [CI] 0.95-1.46). This is also the case for very preterm delivery before 32 weeks of gestation (1.2% compared with 0.7%, OR 1.70; 95% CI 0.98-2.94). Preterm premature rupture of membranes is also increased (2.0% compared with 1.2%, OR 1.67; 95% CI 1.05-2.44). These associations are less strong for second-trimester antibody measurements. The present data do not confirm strong associations between thyroid antibody elevations and preterm birth found in three of five previously published reports. Preterm premature rupture of membranes appears to contribute to the thyroid antibody-associated early deliveries, possibly as a result of inflammation. II.

The relationship between preterm birth and underweight in Asian women.

PubMed

Neggers, Yasmin H

2015-08-15

Although vast improvements have been made in the survival of preterm infants, the toll of preterm birth (PTB) is particularly severe in Asia, with the Indian subcontinent leading the preterm birth rate. Despite the obesity epidemic, maternal underweight remains a common occurrence in developing countries. An association between maternal underweight and preterm birth has been reported in developed countries. A review of epidemiological studies in Asian women in whom association between maternal body mass index (BMI) and risk of PTB was measured, indicated no significant association between low maternal BMI and preterm birth. A hindrance in comparison of these studies is the use of different cut-off point for BMI in defining maternal underweight. As a commentary on published studies it is proposed that that country-specific BMI cut points should be applied for defining underweight for Asian women for the purpose of evaluating the association between maternal underweight and preterm birth. Copyright © 2015 Elsevier Inc. All rights reserved.

Cervical pessaries for prevention of spontaneous preterm birth: past, present and future

PubMed Central

Arabin, B; Alfirevic, Z

2013-01-01

This Review describes the rationale for the use of cervical pessaries to prevent spontaneous preterm birth and their gradual introduction into clinical practice, discusses technical aspects of the more commonly used designs and provides guidance for their use and future evaluation. Possible advantages of cervical pessaries include the easy, ‘one-off’ application, good side-effect profile, good patient tolerance and relatively low cost compared with current alternatives. Use of transvaginal sonography to assess cervical length in the second trimester allows much better selection of patients who may benefit from the use of a cervical pessary, but future clinical trials are needed to establish clearly the role of pessaries as a preterm birth prevention strategy worldwide. PMID:23775862

The association between parity, infant gender, higher level of paternal education and preterm birth in Pakistan: a cohort study.

PubMed

Shaikh, Kiran; Premji, Shahirose S; Rose, Marianne S; Kazi, Ambreen; Khowaja, Shaneela; Tough, Suzanne

2011-11-02

High rates of antenatal depression and preterm birth have been reported in Pakistan. Self reported maternal stress and depression have been associated with preterm birth; however findings are inconsistent. Cortisol is a biological marker of stress and depression, and its measurement may assist in understanding the influence of self reported maternal stress and depression on preterm birth. In a prospective cohort study pregnant women between 28 to 30 weeks of gestation from the Aga Khan Hospital for Women and Children completed the A-Z Stress Scale and the Centre for Epidemiology Studies Depression Scale to assess stress and depression respectively, and had a blood cortisol level drawn. Women were followed up after delivery to determine birth outcomes. Correlation coefficients and Wilcoxon rank sum test was used to assess relationship between preterm birth, stress, depression and cortisol. Logistic regression analysis was used to determine the key factors predictive of preterm birth. 132 pregnant women participated of whom 125 pregnant women had both questionnaire and cortisol level data and an additional seven had questionnaire data only. Almost 20% of pregnant women (19·7%, 95% CI 13·3-27·5) experienced a high level of stress and nearly twice as many (40·9%, 95% CI 32·4-49·8%) experienced depressive symptoms. The median of cortisol level was 27·40 ug/dl (IQR 22·5-34·2). The preterm birth rate was 11·4% (95% CI 6·5-18). There was no relationship between cortisol values and stress scale or depression. There was a significant positive relationship between maternal depression and stress. Preterm birth was associated with higher parity, past delivery of a male infant, and higher levels of paternal education. Insufficient numbers of preterm births were available to warrant the development of a multivariable logistic regression model. Preterm birth was associated with higher parity, past delivery of a male infant, and higher levels of paternal education. There was no relationship between stress, and depression, cortisol and preterm birth. There were high rates of stress and depression among this sample suggesting that there are missed opportunities to address mental health needs in the prenatal period. Improved methods of measurement are required to better understand the psychobiological basis of preterm birth.

Comparing exposure assessment methods for traffic-related air pollution in an adverse pregnancy outcome study.

PubMed

Wu, Jun; Wilhelm, Michelle; Chung, Judith; Ritz, Beate

2011-07-01

Previous studies reported adverse impacts of traffic-related air pollution exposure on pregnancy outcomes. Yet, little information exists on how effect estimates are impacted by the different exposure assessment methods employed in these studies. To compare effect estimates for traffic-related air pollution exposure and preeclampsia, preterm birth (gestational age less than 37 weeks), and very preterm birth (gestational age less than 30 weeks) based on four commonly used exposure assessment methods. We identified 81,186 singleton births during 1997-2006 at four hospitals in Los Angeles and Orange Counties, California. Exposures were assigned to individual subjects based on residential address at delivery using the nearest ambient monitoring station data [carbon monoxide (CO), nitrogen dioxide (NO(2)), nitric oxide (NO), nitrogen oxides (NO(x)), ozone (O(3)), and particulate matter less than 2.5 (PM(2.5)) or less than 10 (PM(10))μm in aerodynamic diameter], both unadjusted and temporally adjusted land-use regression (LUR) model estimates (NO, NO(2), and NO(x)), CALINE4 line-source air dispersion model estimates (NO(x) and PM(2.5)), and a simple traffic-density measure. We employed unconditional logistic regression to analyze preeclampsia in our birth cohort, while for gestational age-matched risk sets with preterm and very preterm birth we employed conditional logistic regression. We observed elevated risks for preeclampsia, preterm birth, and very preterm birth from maternal exposures to traffic air pollutants measured at ambient stations (CO, NO, NO(2), and NO(x)) and modeled through CALINE4 (NO(x) and PM(2.5)) and LUR (NO(2) and NO(x)). Increased risk of preterm birth and very preterm birth were also positively associated with PM(10) and PM(2.5) air pollution measured at ambient stations. For LUR-modeled NO(2) and NO(x) exposures, elevated risks for all the outcomes were observed in Los Angeles only--the region for which the LUR models were initially developed. Unadjusted LUR models often produced odds ratios somewhat larger in size than temporally adjusted models. The size of effect estimates was smaller for exposures based on simpler traffic density measures than the other exposure assessment methods. We generally confirmed that traffic-related air pollution was associated with adverse reproductive outcomes regardless of the exposure assessment method employed, yet the size of the estimated effect depended on how both temporal and spatial variations were incorporated into exposure assessment. The LUR model was not transferable even between two contiguous areas within the same large metropolitan area in Southern California. Copyright © 2011 Elsevier Inc. All rights reserved.

Preterm birth, infant weight gain, and childhood asthma risk: a meta-analysis of 147,000 European children.

PubMed

Sonnenschein-van der Voort, Agnes M M; Arends, Lidia R; de Jongste, Johan C; Annesi-Maesano, Isabella; Arshad, S Hasan; Barros, Henrique; Basterrechea, Mikel; Bisgaard, Hans; Chatzi, Leda; Corpeleijn, Eva; Correia, Sofia; Craig, Leone C; Devereux, Graham; Dogaru, Cristian; Dostal, Miroslav; Duchen, Karel; Eggesbø, Merete; van der Ent, C Kors; Fantini, Maria P; Forastiere, Francesco; Frey, Urs; Gehring, Ulrike; Gori, Davide; van der Gugten, Anne C; Hanke, Wojciech; Henderson, A John; Heude, Barbara; Iñiguez, Carmen; Inskip, Hazel M; Keil, Thomas; Kelleher, Cecily C; Kogevinas, Manolis; Kreiner-Møller, Eskil; Kuehni, Claudia E; Küpers, Leanne K; Lancz, Kinga; Larsen, Pernille S; Lau, Susanne; Ludvigsson, Johnny; Mommers, Monique; Nybo Andersen, Anne-Marie; Palkovicova, Lubica; Pike, Katharine C; Pizzi, Costanza; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Roberts, Graham; Schmidt, Anne; Sram, Radim J; Sunyer, Jordi; Thijs, Carel; Torrent, Maties; Viljoen, Karien; Wijga, Alet H; Vrijheid, Martine; Jaddoe, Vincent W V; Duijts, Liesbeth

2014-05-01

Preterm birth, low birth weight, and infant catch-up growth seem associated with an increased risk of respiratory diseases in later life, but individual studies showed conflicting results. We performed an individual participant data meta-analysis for 147,252 children of 31 birth cohort studies to determine the associations of birth and infant growth characteristics with the risks of preschool wheezing (1-4 years) and school-age asthma (5-10 years). First, we performed an adjusted 1-stage random-effect meta-analysis to assess the combined associations of gestational age, birth weight, and infant weight gain with childhood asthma. Second, we performed an adjusted 2-stage random-effect meta-analysis to assess the associations of preterm birth (gestational age <37 weeks) and low birth weight (<2500 g) with childhood asthma outcomes. Younger gestational age at birth and higher infant weight gain were independently associated with higher risks of preschool wheezing and school-age asthma (P < .05). The inverse associations of birth weight with childhood asthma were explained by gestational age at birth. Compared with term-born children with normal infant weight gain, we observed the highest risks of school-age asthma in children born preterm with high infant weight gain (odds ratio [OR], 4.47; 95% CI, 2.58-7.76). Preterm birth was positively associated with an increased risk of preschool wheezing (pooled odds ratio [pOR], 1.34; 95% CI, 1.25-1.43) and school-age asthma (pOR, 1.40; 95% CI, 1.18-1.67) independent of birth weight. Weaker effect estimates were observed for the associations of low birth weight adjusted for gestational age at birth with preschool wheezing (pOR, 1.10; 95% CI, 1.00-1.21) and school-age asthma (pOR, 1.13; 95% CI, 1.01-1.27). Younger gestational age at birth and higher infant weight gain were associated with childhood asthma outcomes. The associations of lower birth weight with childhood asthma were largely explained by gestational age at birth. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Preterm birth, infant weight gain, and childhood asthma risk: A meta-analysis of 147,000 European children

PubMed Central

Sonnenschein-van der Voort, Agnes M.M.; Arends, Lidia R.; de Jongste, Johan C.; Annesi-Maesano, Isabella; Arshad, S. Hasan; Barros, Henrique; Basterrechea, Mikel; Bisgaard, Hans; Chatzi, Leda; Corpeleijn, Eva; Correia, Sofia; Craig, Leone C.; Devereux, Graham; Dogaru, Cristian; Dostal, Miroslav; Duchen, Karel; Eggesbø, Merete; van der Ent, C. Kors; Fantini, Maria P.; Forastiere, Francesco; Frey, Urs; Gehring, Ulrike; Gori, Davide; van der Gugten, Anne C.; Hanke, Wojciech; Henderson, A. John; Heude, Barbara; Iñiguez, Carmen; Inskip, Hazel M.; Keil, Thomas; Kelleher, Cecily C.; Kogevinas, Manolis; Kreiner-Møller, Eskil; Kuehni, Claudia E.; Küpers, Leanne K.; Lancz, Kinga; Larsen, Pernille S.; Lau, Susanne; Ludvigsson, Johnny; Mommers, Monique; Nybo Andersen, Anne-Marie; Palkovicova, Lubica; Pike, Katharine C.; Pizzi, Costanza; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Roberts, Graham; Schmidt, Anne; Sram, Radim J.; Sunyer, Jordi; Thijs, Carel; Torrent, Maties; Viljoen, Karien; Wijga, Alet H.; Vrijheid, Martine; Jaddoe, Vincent W.V.; Duijts, Liesbeth

2014-01-01

Background Preterm birth, low birth weight, and infant catch-up growth seem associated with an increased risk of respiratory diseases in later life, but individual studies showed conflicting results. Objectives We performed an individual participant data meta-analysis for 147,252 children of 31 birth cohort studies to determine the associations of birth and infant growth characteristics with the risks of preschool wheezing (1-4 years) and school-age asthma (5-10 years). Methods First, we performed an adjusted 1-stage random-effect meta-analysis to assess the combined associations of gestational age, birth weight, and infant weight gain with childhood asthma. Second, we performed an adjusted 2-stage random-effect meta-analysis to assess the associations of preterm birth (gestational age <37 weeks) and low birth weight (<2500 g) with childhood asthma outcomes. Results Younger gestational age at birth and higher infant weight gain were independently associated with higher risks of preschool wheezing and school-age asthma (P < .05). The inverse associations of birth weight with childhood asthma were explained by gestational age at birth. Compared with term-born children with normal infant weight gain, we observed the highest risks of school-age asthma in children born preterm with high infant weight gain (odds ratio [OR], 4.47; 95% CI, 2.58-7.76). Preterm birth was positively associated with an increased risk of preschool wheezing (pooled odds ratio [pOR], 1.34; 95% CI, 1.25-1.43) and school-age asthma (pOR, 1.40; 95% CI, 1.18-1.67) independent of birth weight. Weaker effect estimates were observed for the associations of low birth weight adjusted for gestational age at birth with preschool wheezing (pOR, 1.10; 95% CI, 1.00-1.21) and school-age asthma (pOR, 1.13; 95% CI, 1.01-1.27). Conclusion Younger gestational age at birth and higher infant weight gain were associated with childhood asthma outcomes. The associations of lower birth weight with childhood asthma were largely explained by gestational age at birth. PMID:24529685

Trends in preterm births in Flanders, Belgium, from 1991 to 2002.

PubMed

Keirse, Marc J N C; Hanssens, Myriam; Devlieger, Hugo

2009-11-01

Changes in the preterm birth rate have been attributed predominantly to increases in multiple pregnancies, associated with advanced maternal age and assisted reproduction, and to obstetric intervention. We examined their contribution to the frequencies of preterm (<37 weeks), very preterm (<32 weeks) and severely preterm (<28 weeks) birth among 700 383 singleton and twin births in Flanders from 1991 to 2002. We examined changes across four 3-year periods (triennia) with confidence interval [CI] analysis and yearly incremental rates using linear and logistic regression analyses. Over the 12 years, twin pregnancies increased from 1.5% to 2.0%, averaging 1.6% [95% CI 1.54, 1.66] in 1991-93 and 1.9% [95% CI 1.81, 1.94] in 2000-02 (P < 0.001). The proportion of women aged 35 years or more increased from 6.8% [95% CI 6.69, 6.92] in 1991-93 to 11.3% [95% CI 11.2, 11.5] in 2000-02 (P < 0.001) and those aged under 20 from 1.9% [95% CI 1.81, 1.93] to 2.3% [95% CI 2.26, 2.41] (P < 0.001). Assisted reproduction increased from 2.6% [95% CI 2.48, 2.62] to 4.2% [95% CI 4.11, 4.30] (P < 0.001) and obstetric intervention to end pregnancy from 36.2% [95% CI 36.0, 36.4] to 40.3% [95% CI 40.1, 40.6] (P < 0.001). These increases related to an annual increase of 0.23% in the preterm birth rate from 5.5% [95% CI 5.4, 5.6] in 1991-93 to 7.2% [95% CI 7.1, 7.3] in 2000-02 (P < 0.001). The proportions of very and severely preterm births also increased by nearly a third, but their contribution to the total preterm birth rate remained stable at 15% and 5%, respectively. Odds ratios for the increases per year were 1.035 [95% CI 1.032, 1.038] for preterm birth, 1.024 [95% CI 1.018, 1.031] for very preterm and 1.028 [95% CI 1.017, 1.040] for severely preterm births after adjusting for other changes in the population. Overall, the data show, first, marked increases in the frequency of known contributors to the preterm birth rate, including twin pregnancies, advanced maternal age, assisted reproduction and obstetric intervention. Second, the preterm birth rate further increased significantly within subgroups of women with one or more of these characteristics. Third, the preterm birth rate also rose, from 4.4% [95% CI 4.2, 4.5] in 1991-93 to 5.6% [95% CI 5.5, 5.8] in 2000-02 (P < 0.001), in women with none of these contributing factors. This indicates that changes in the frequency of these known predictors are insufficient to explain the steady increase in preterm, very preterm and severely preterm births over more than a decade.

Long-Term Effects of Preterm Birth on Language and Literacy at Eight Years

ERIC Educational Resources Information Center

Guarini, Annalisa; Sansavini, Alessandra; Fabbri, Cristina; Savini, Silvia; Alessandroni, Rosina; Faldella, Giacomo; Karmiloff-Smith, Annette

2010-01-01

The aims of this study were to investigate whether specific linguistic difficulties in preterm children persist at eight years and to examine the interrelationships between language and literacy in this population, compared with a control group of full-term children. Sixty-eight monolingual Italian preterms and 26 chronologically matched controls…

Birth outcomes among offspring of women exposed to the September 11, 2001, terrorist attacks.

PubMed

Lipkind, Heather S; Curry, Allison E; Huynh, Mary; Thorpe, Lorna E; Matte, Thomas

2010-10-01

To evaluate the effects of the September 11, 2001, World Trade Center attacks on birth outcomes. Live singleton births between September 11, 2001, and October 31, 2002, to women enrolled in a World Trade Center Health Registry (the Registry, n=446) were compared with births to women residing more than 5 miles from the World Trade Center (n=49,616). Birth weight, gestational age, low birth weight, and preterm delivery were evaluated using linear and logistic regression. Births before September 11, 2001, were analyzed to assess possible seasonal biases of associations with pregnancy trimester on September 11. Associations of birth outcomes with September 11-related psychologic stress and physical exposures were assessed among births to women within the Registry (n=499). Birth weight and gestational age distributions were similar for births to women enrolled in the Registry and comparison births. Although mean gestational age and birth weight varied with trimester on September 11, a similar association was found among births in previous years, consistent with a seasonal effect not related to exposure. Registry-linked births to mothers with probable posttraumatic stress disorder (n=61) had a higher odds of low birth weight (adjusted odds ratio [OR] 2.49, 95% confidence interval [CI] 1.02-6.08) and preterm delivery (adjusted OR 2.48, 95% CI 1.05-5.84) compared with births to women without posttraumatic stress disorder. Women who lived, worked, or were near the World Trade Center on or soon after September 11 had pregnancy outcomes similar to women residing more than 5 miles away. However, among exposed women, probable posttraumatic stress disorder was associated with low birth weight and preterm delivery. II.

Perspectives in the prevention of premature birth.

PubMed

Ancel, Pierre-Yves

2004-11-15

Obstetric and neonatal interventions have improved the survival of preterm infants, but there has not been an equivalent reduction in long-term neurological disability. Thus, some effort must be invested in finding ways of preventing preterm birth. Numerous programmes have been promoted to address the matter of how the frequency of preterm birth could be prevented. Most interventions intended to prevent preterm labour do not have the desired effect, except for antibiotic treatment in cases of asymptomatic bacteriuria or bacterial vaginosis and progesterone administered prophylactically in high-risk women. Tocolytic drugs appear to delay delivery long enough for successful administration of corticosteroids in women in preterm labour, but without decreasing the risk of preterm birth. Some authors promote public health approaches that address all risk factors and affect the entire population of pregnant women, given that prevention programmes directed only at high-risk women have had little effect in preventing preterm births. However, the lack of progress in reducing the frequency of preterm births is also due to our limited understanding of the aetiology of preterm delivery. Although there is growing evidence that infection and neuroendocrine processes are involved, progress has remained slow. Recently, the hypothesis of a genetic predisposition to preterm delivery has been set up. Additional research exploring the pathophysiology of preterm labour is obviously needed, which will hopefully lead to the development of new therapeutic approaches.

Brain Barrier Disruption and Region-Specific Neuronal Degeneration during Necrotizing Enterocolitis in Preterm Pigs.

PubMed

Brunse, Anders; Abbaspour, Afrouz; Sangild, Per Torp

2018-06-06

Necrotizing enterocolitis (NEC) increases the risk of brain injury and impaired neurodevelopment. Rapid brain maturation prior to birth may explain why preterm brains are particularly vulnerable to serious infections. Using pigs as models, we hypothesized that preterm birth was associated with altered blood-cerebrospinal fluid (CSF) barrier (BCSFB) function and cerebral structural deficits, and that NEC was associated with systemic inflammation, BCSFB disruption, and neuroinflammation. First, cesarean-delivered preterm and term pigs (n = 43-44) were euthanized at birth to investigate BCSFB function and markers of brain structural maturation, or on day 5 to measure markers of blood-brain barrier maturation in the hippocampus and striatum (experiment 1). Next, preterm pigs (n = 162) were fed increasing volumes of infant formula to assess NEC lesions, systemic inflammation, BCSFB permeability, cerebral histopathology, hippocampal micro-glial density, and cytokine levels on day 5 (experiments 2 and 3). In experiment 1, preterm newborns had increased CSF-plasma ratios of albumin and raffinose, reduced CSF glucose levels, as well as increased cerebral hydration and reduced white matter myelination compared with term animals. We observed lower hippocampal (but not striatal) perivascular astrocyte coverage for the first 5 days after preterm birth, accompanied by altered cell junction protein levels. In experiments 2 and- 3, piglets with severe NEC lesions showed reduced blood thrombocytes and increased plasma C-reactive protein and interleukin-6 levels. NEC was associated with increased CSF-plasma albumin and raffinose ratios, reduced CSF leukocyte numbers, and increased cerebral hydration. In the hippocampus, NEC was associated with pyramidal neuron loss and increased interleukin-6 levels. In the short term, NEC did not affect cerebral myelination or microglia density. In conclusion, altered BCSFB properties and brain structural deficits were observed in pigs after preterm birth. Acute gastrointestinal NEC lesions were associated with systemic inflammation, increased BCSFB permeability and region-specific neuronal damage. The results demonstrate the importance of early interventions against NEC to prevent brain injury in preterm infants. © 2018 S. Karger AG, Basel.

Pulmonary outcome in former preterm, very low birth weight children with bronchopulmonary dysplasia: a case-control follow-up at school age.

PubMed

Vom Hove, Maike; Prenzel, Freerk; Uhlig, Holm H; Robel-Tillig, Eva

2014-01-01

To assess and compare long-term pulmonary outcomes in former preterm-born, very low birth weight (VLBW) children with and without bronchopulmonary dysplasia (BPD) born in the surfactant era. Pulmonary function tests (ie, spirometry, body plethysmography, and gas transfer testing) were performed in children with a history of VLBW and BPD (n = 28) and compared with a matched preterm-born VLBW control group (n = 28). Medical history was evaluated by questionnaire. At time of follow-up (mean age, 9.5 years), respiratory symptoms (36% vs 8%) and receipt of asthma medication (21% vs 0%) were significantly more frequent in the preterm-born children with previous BPD than in those with no history of BPD. The children with a history of BPD had significantly lower values for forced expiratory volume in 1 second (z-score -1.27 vs -0.4; P = .008), forced vital capacity (z-score -1.39 vs -0.71 z-score; P = .022), and forced expiratory flow rate at 50% of forced vital capacity (z-score -2.21 vs -1.04; P = .048) compared with the preterm control group. Preterm-born children with a history of BPD are significantly more likely to have lung function abnormalities, such as airway obstruction and respiratory symptoms, at school age compared with preterm-born children without BPD. Copyright © 2014 Mosby, Inc. All rights reserved.

Relationship between Periodontal Diseases and Preterm Birth: Recent Epidemiological and Biological Data

PubMed Central

Huck, O.; Tenenbaum, H.; Davideau, J.-L.

2011-01-01

For ten years, the incidence of preterm birth does not decrease in developed countries despite the promotion of public health programs. Many risk factors have been identified including ethnicity, age, tobacco, and infection. However, almost 50% of preterm birth causes remain unknown. The periodontal diseases are highly prevalent inflammatory and infectious diseases of tooth supporting tissues leading to an oral disability. They influence negatively general health worsening cardiovascular diseases and diabetes. Periodontal diseases have been also suspected to increase the rate of preterm birth, but data remain contradictory. The objective of this review is to present the principal results of epidemiological, biological, and interventional studies on the link between periodontal diseases and preterm birth. The conclusions of this work underline the importance for the physician/obstetrician to identify women at risk for preterm birth and to address these patients to dentist for periodontal examination and treatment in order to limit adverse pregnancy outcomes. PMID:22132334

Periodontal disease activity measured by the benzoyl-DL-arginine-naphthylamide test is associated with preterm births.

PubMed

Chan, Hui-Chen; Wu, Chen-Tsai; Welch, Kathleen B; Loesche, Walter J

2010-07-01

Infection is a risk factor for preterm birth. This study was conducted in the field and addressed the link between periodontal pathogens measured with the benzoyl-DL-arginine-naphthylamide (BANA) test and preterm birth. This prospective study was performed in Changhua, Taiwan. Periodontal examinations included the plaque index, papillary bleeding scores, and measurement of the BANA enzyme in plaque samples at the second and third trimesters. Independent variables included maternal demographic characteristics, previous pregnancy histories, risk factors, plaque and gingivitis scores, and current pregnancy outcomes. There were 19 (7%) preterm deliveries among the 268 subjects. A history of a previous preterm birth and low birth weight, frequency of prenatal visits, preterm uterine contractions, antepartum hemorrhages, placenta previae, and preterm premature rupture of membranes were significantly related to preterm birth (P = 0.035, 0.027, <0.001, 0.025, 0.006, 0.014, and <0.001, respectively). Maternal weight gain was higher with a normal term delivery (P = 0.003). Multivariable logistic regression analyses showed that the number of BANA-infected sites in the third trimester (odds ratio [OR]: 5.89; 95% confidence interval [CI]: 1.5 to 31.6), maternal weight gain (OR: 0.78; 95% CI: 0.65 to 0.91), antepartum hemorrhages (OR: 10.0; 95% CI: 2.2 to 46.9), and preterm premature rupture of membranes (OR: 12.6; 95% CI: 3.97 to 42.71) had significant influences on preterm-birth outcomes. BANA-positive plaque in the third trimester was associated with preterm births after controlling for other risk factors. The BANA test can be used to screen pregnant women at chairside and/or bedside to apply suitable intervention tactics.

The Influence of Meteorological Factors and Atmospheric Pollutants on the Risk of Preterm Birth.

PubMed

Giorgis-Allemand, Lise; Pedersen, Marie; Bernard, Claire; Aguilera, Inmaculada; Beelen, Rob M J; Chatzi, Leda; Cirach, Marta; Danileviciute, Asta; Dedele, Audrius; van Eijsden, Manon; Estarlich, Marisa; Fernández-Somoano, Ana; Fernández, Mariana F; Forastiere, Francesco; Gehring, Ulrike; Grazuleviciene, Regina; Gruzieva, Olena; Heude, Barbara; Hoek, Gerard; de Hoogh, Kees; van den Hooven, Edith H; Håberg, Siri E; Iñiguez, Carmen; Jaddoe, Vincent W V; Korek, Michal; Lertxundi, Aitana; Lepeule, Johanna; Nafstad, Per; Nystad, Wenche; Patelarou, Evridiki; Porta, Daniela; Postma, Dirkje; Raaschou-Nielsen, Ole; Rudnai, Peter; Siroux, Valérie; Sunyer, Jordi; Stephanou, Euripides; Sørensen, Mette; Eriksen, Kirsten Thorup; Tuffnell, Derek; Varró, Mihály J; Vrijkotte, Tanja G M; Wijga, Alet; Wright, John; Nieuwenhuijsen, Mark J; Pershagen, Göran; Brunekreef, Bert; Kogevinas, Manolis; Slama, Rémy

2017-02-15

Atmospheric pollutants and meteorological conditions are suspected to be causes of preterm birth. We aimed to characterize their possible association with the risk of preterm birth (defined as birth occurring before 37 completed gestational weeks). We pooled individual data from 13 birth cohorts in 11 European countries (71,493 births from the period 1994-2011, European Study of Cohorts for Air Pollution Effects (ESCAPE)). City-specific meteorological data from routine monitors were averaged over time windows spanning from 1 week to the whole pregnancy. Atmospheric pollution measurements (nitrogen oxides and particulate matter) were combined with data from permanent monitors and land-use data into seasonally adjusted land-use regression models. Preterm birth risks associated with air pollution and meteorological factors were estimated using adjusted discrete-time Cox models. The frequency of preterm birth was 5.0%. Preterm birth risk tended to increase with first-trimester average atmospheric pressure (odds ratio per 5-mbar increase = 1.06, 95% confidence interval: 1.01, 1.11), which could not be distinguished from altitude. There was also some evidence of an increase in preterm birth risk with first-trimester average temperature in the -5°C to 15°C range, with a plateau afterwards (spline coding, P = 0.08). No evidence of adverse association with atmospheric pollutants was observed. Our study lends support for an increase in preterm birth risk with atmospheric pressure. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The predictive value of quantitative fibronectin testing in combination with cervical length measurement in symptomatic women.

PubMed

Bruijn, Merel M C; Kamphuis, Esme I; Hoesli, Irene M; Martinez de Tejada, Begoña; Loccufier, Anne R; Kühnert, Maritta; Helmer, Hanns; Franz, Marie; Porath, Martina M; Oudijk, Martijn A; Jacquemyn, Yves; Schulzke, Sven M; Vetter, Grit; Hoste, Griet; Vis, Jolande Y; Kok, Marjolein; Mol, Ben W J; van Baaren, Gert-Jan

2016-12-01

The combination of the qualitative fetal fibronectin test and cervical length measurement has a high negative predictive value for preterm birth within 7 days; however, positive prediction is poor. A new bedside quantitative fetal fibronectin test showed potential additional value over the conventional qualitative test, but there is limited evidence on the combination with cervical length measurement. The purpose of this study was to compare quantitative fetal fibronectin and qualitative fetal fibronectin testing in the prediction of spontaneous preterm birth within 7 days in symptomatic women who undergo cervical length measurement. We performed a European multicenter cohort study in 10 perinatal centers in 5 countries. Women between 24 and 34 weeks of gestation with signs of active labor and intact membranes underwent quantitative fibronectin testing and cervical length measurement. We assessed the risk of preterm birth within 7 days in predefined strata based on fibronectin concentration and cervical length. Of 455 women who were included in the study, 48 women (11%) delivered within 7 days. A combination of cervical length and qualitative fibronectin resulted in the identification of 246 women who were at low risk: 164 women with a cervix between 15 and 30 mm and a negative fibronectin test (<50 ng/mL; preterm birth rate, 2%) and 82 women with a cervix at >30 mm (preterm birth rate, 2%). Use of quantitative fibronectin alone resulted in a predicted risk of preterm birth within 7 days that ranged from 2% in the group with the lowest fibronectin level (<10 ng/mL) to 38% in the group with the highest fibronectin level (>500 ng/mL), with similar accuracy as that of the combination of cervical length and qualitative fibronectin. Combining cervical length and quantitative fibronectin resulted in the identification of an additional 19 women at low risk (preterm birth rate, 5%), using a threshold of 10 ng/mL in women with a cervix at <15 mm, and 6 women at high risk (preterm birth rate, 33%) using a threshold of >500 ng/mL in women with a cervix at >30 mm. In women with threatened preterm birth, quantitative fibronectin testing alone performs equal to the combination of cervical length and qualitative fibronectin. Possibly, the combination of quantitative fibronectin testing and cervical length increases this predictive capacity. Cost-effectiveness analysis and the availability of these tests in a local setting should determine the final choice. Copyright © 2016 Elsevier Inc. All rights reserved.

Race and ethnic disparities in fetal mortality, preterm birth, and infant mortality in the United States: an overview.

PubMed

MacDorman, Marian F

2011-08-01

Infant mortality, fetal mortality, and preterm birth all represent important health challenges that have shown little recent improvement. The rate of decrease in both fetal and infant mortality has slowed in recent years, with little decrease since 2000 for infant mortality, and no significant decrease from 2003 to 2005 for fetal mortality. The percentage of preterm births increased by 36% from 1984 to 2006, and then decreased by 4% from 2006 to 2008. There are substantial race and ethnic disparities in fetal and infant mortality and preterm birth, with non-Hispanic black women at greatest risk of unfavorable birth outcomes, followed by American Indian and Puerto Rican women. Infant mortality, fetal mortality, and preterm birth are multifactorial and interrelated problems with similarities in etiology, risk factors and disease pathways. Preterm birth prevention is critical to lowering the infant mortality rate, and to reducing race and ethnic disparities in infant mortality. Published by Elsevier Inc.

The inner state differences of preterm birth rates in Brazil: a time series study.

PubMed

de Oliveira, Rosana Rosseto; Melo, Emiliana Cristina; Fujimori, Elizabeth; Mathias, Thais Aidar de Freitas

2016-05-17

Preterm birth is a serious public health problem, as it is linked to high rates of neonatal and child morbidity and mortality. The prevalence of premature births has increased worldwide, with regional differences. The objective of this study was to analyze the trend of preterm births in the state of Paraná, Brazil, according to Macro-regional and Regional Health Offices (RHOs). This is an ecological time series study using preterm births records from the national live birth registry system of Brazil's National Health Service - Live Birth Information System (Sinasc), for residents of the state of Paraná, Brazil, between 2000 and 2013. The preterm birth rates was calculated on a yearly basis and grouped into three-year periods (2000-2002, 2003-2005, 2006-2008, 2009-2011) and one two-year period (2012-2013), according to gestational age and mother's Regional Health Office of residence. The polynomial regression model was used for trend analysis. The predominance of preterm birth rate increased from 6.8 % in 2000 to 10.5 % in 2013, with an average increase of 0.20 % per year (r(2) = 0.89), and a greater share of moderate preterm births (32 to <37 weeks), which increased from 5.8 % to 9 %. The same pattern was observed for all Macro-regional Health Offices, with highlight to the Northern Macro-Regional Office, which showed the highest average rate of prematurity and average annual growth during that period (7.55 % and 0.35 %, respectively). The trend analysis of preterm birth rates according to RHO showed a growing trend for almost all RHOs - except for the 7(th) RHO where a declining trend was observed (-0.95 a year); and in the 20(th), 21(st) and 22(nd) RHOs which remained unchanged. In the last three-year of the study period (2011-2013), no RHO showed preterm birth rates below 7.3 % or prevalence of moderate preterm birth below 9.4 %. The results show an increase in preterm births with differences among Macro-regional and RHOs, which indicate the need to improve actions during the prenatal period according to the specificities of each region.

Associations of neighborhood-level racial residential segregation with adverse pregnancy outcomes.

PubMed

Salow, Arturo D; Pool, Lindsay R; Grobman, William A; Kershaw, Kiarri N

2018-03-01

Previous analyses utilizing birth certificate data have shown environmental factors such as racial residential segregation may contribute to disparities in adverse pregnancy outcomes. However, birth certificate data are ill equipped to reliably differentiate among small for gestational age, spontaneous preterm birth, and medically indicated preterm birth. We sought to utilize data from electronic medical records to determine whether residential segregation among Black women is associated with an increased risk of adverse pregnancy outcomes. The study population was composed of 4770 non-Hispanic Black women who delivered during the years 2009 through 2013 at a single urban medical center. Addresses were geocoded at the level of census tract, and this tract was used to determine the degree of residential segregation for an individual's neighborhood. Residential segregation was measured using the Gi* statistic, a z-score that measures the extent to which the neighborhood racial composition deviates from the composition of the larger surrounding area. The Gi* statistic z-scores were categorized as follows: low (z < 0), medium (z = 0-1.96), and high (z > 1.96). Adverse pregnancy outcomes included overall preterm birth, spontaneous preterm birth, medically indicated preterm birth, and small for gestational age. Hierarchical logistic regression models accounting for clustering by census tract and repeated births among mothers were used to estimate odds ratios of adverse pregnancy outcomes associated with segregation. In high segregation areas, the prevalence of overall preterm birth was significantly higher than that in low segregation areas (15.5% vs 10.7%, respectively; P < .001). Likewise, the prevalence of spontaneous preterm birth and medically indicated preterm birth were higher in high (9.5% and 6.0%) vs low (6.2% and 4.6%) segregation neighborhoods (P < .001 and P = .046, respectively). The associations of high segregation with overall preterm birth (odds ratio, 1.31; 95% confidence interval, 1.02-1.69) and spontaneous preterm birth (odds ratio, 1.37; 95% confidence interval, 1.02-1.85) remained significant with adjustment for neighborhood poverty, insurance status, parity, and maternal medical conditions. Among non-Hispanic Black women in an urban area, high levels of segregation were independently associated with the higher odds of spontaneous preterm birth. These findings highlight one aspect of social determinants (ie, segregation) through which adverse pregnancy outcomes may be influenced and points to a potential target for intervention. Copyright © 2018 Elsevier Inc. All rights reserved.

What Interventions Are Being Used to Prevent Preterm Birth and When?

PubMed

Feng, Yu Yang; Jarde, Alexander; Seo, Ye Rin; Powell, Anne; Nwebube, Nwachukwu; McDonald, Sarah D

2018-05-01

This study sought to determine the proportions of women at risk of preterm birth who received progesterone, elective and rescue cerclage, or pessary to prevent preterm birth, by using medical records. The authors also sought to determine whether these proportions differed among primary-, secondary-, and tertiary-level centres. The authors conducted a retrospective cohort study and extracted data from consecutive medical charts of women with an estimated date of confinement over 3 months in primary-, secondary-, and tertiary-level centres in Southern Ontario. The study identified women with a previous spontaneous preterm birth or a short cervix and determined whether they were offered and whether they received a preventive intervention for preterm birth. Descriptive statistics and Fisher exact tests were calculated. The authors reviewed 1024 consecutive charts at primary, secondary, and tertiary centres and identified 31 women with a previous spontaneous preterm birth or a short cervix. Of these women, less than one half (42%) received progesterone or cerclage for prevention of preterm birth, and none received pessary. One in four women (26%) were not referred to an obstetrician or maternal-fetal medicine specialist in time for an intervention, and among those referred before 24 weeks of gestation, an intervention was offered to 57% of the women. Less than half of women at risk of spontaneous preterm birth received progesterone, cerclage, or pessary, attesting to the importance of improving knowledge translation methods to encourage timely referral and use of progesterone for the prevention of preterm birth. Copyright © 2018 Society of Obstetricians and Gynaecologists of Canada. Published by Elsevier Inc. All rights reserved.

Swedish and American studies show that initiatives to decrease maternal obesity could play a key role in reducing preterm birth.

PubMed

Gould, Jeffrey B; Mayo, Jonathan; Shaw, Gary M; Stevenson, David K

2014-06-01

Maternal obesity is a major source of preventable perinatal morbidity, but studies of the relationship between obesity and preterm birth have been inconsistent. This review looks at two major studies covering just under 3.5 million births, from California, USA, and Sweden. Inconsistent findings in previous studies appear to stem from the complex relationship between obesity and preterm birth. Initiatives to decrease maternal obesity represent an important strategy in reducing preterm birth. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Detection and risk stratification of women at high risk of preterm birth in rural communities near Nagpur, India.

PubMed

Patel, Archana; Prakash, Amber Abhijeet; Pusdekar, Yamini V; Kulkarni, Hemant; Hibberd, Patricia

2017-09-19

Presently, preterm birth is globally the leading cause of neonatal mortality. Prompt community based identification of women at high risk for preterm births (HRPB) can either help to avert preterm births or avail effective interventions to reduce neonatal mortality due to preterm births. We evaluated the performance of a package to train community workers to detect the presence of signs or symptoms of HRPB. Pregnant women enrolled in the intervention arm of a cluster randomized trial of Antenatal Corticosteroids (ACT Trial) conducted at Nagpur, India were informed about 4 directly observable signs and symptoms of preterm labor. Community health workers actively monitored these women from 24 to 36 weeks of gestation for these signs or symptoms. If they were present (HRPB positive) the identified women were brought to government health facilities for assessment and management. HRPB positive could also be determined by the provider if the woman presented directly to the facility. Risk stratification was based on the number of signs or symptoms present. The outcome of preterm birth was based on the clinical assessment of gestational age < 37 weeks at delivery or a birth weight of <2000 g. Between July 1, 2012 and 30 November, 2013, 686 of 7050 (9.7%) pregnant women studied, delivered preterm. 732 (10.4%) women were HRPB positive, of whom 333 (45.5%) delivered preterm. Of the remaining 6318(89.6%) HRPB negative women 353 (5.6%) delivered preterm. The likelihood ratio (LR) of a preterm birth in the HRPB positives was 8.14 (95% confidence interval 7.16-9.26). The LR of a preterm birth increased in women who had more signs or symptoms of HRBP (p < 0.00001). More signs or symptoms of HRPB were also associated with a shorter time to delivery, lower birth weight and higher rates of stillbirths, neonatal deaths and postnatal complications. Addition of risk stratification improved the prediction of preterm delivery (Integrated Discrimination Improvement 17% (95% CI 15-19%)). The package for detection of signs and symptoms of HRPB is feasible, promising and likely to improve management of preterm labor. NCT01073475 on February 21, 2010 and NCT01084096 on March 9, 2010.

Cervical pessary to reduce preterm birth before 34 weeks of gestation after an episode of preterm labor and a short cervix: a randomized controlled trial.

PubMed

Pratcorona, Laia; Goya, Maria; Merced, Carme; Rodó, Carlota; Llurba, Elisa; Higueras, Teresa; Cabero, Luis; Carreras, Elena

2018-04-25

To date, no intervention has proved effective in reducing the spontaneous preterm birth rate in singleton pregnancies following an episode of threatened preterm labor and short cervix remaining. This study was designed to ascertain whether cervical pessaries could be useful in preventing spontaneous preterm birth in women with singleton pregnancies and a short cervix after a threatened preterm labor episode. This open randomized controlled trial was conducted in 357 pregnant women (between 24 0 and 33 6 weeks) who had not delivered 48h after a threatened preterm labor episode and had a short cervix remaining (≤25 mm at 24 0 -29 6 weeks; ≤15mm at 30 0 -33 6 weeks). Patients were randomly assigned to cervical pessary (179) or routine management (178). The primary outcome was the spontaneous preterm birth rate before 34 weeks. Spontaneous preterm birth before 28 and 37 weeks and neonatal morbidity and mortality were also evaluated in an intention-to-treat analysis. No significant differences between the pessary and routine management groups were observed in the spontaneous preterm birth rate before 34 weeks (19/177 [10.7%] in the pessary group vs. 24/175 [13.7%] in the control group; relative risk, 0.78; 95% confidence interval, 0.45-1.38). Spontaneous preterm birth before 37 weeks occurred less frequently in the pessary group (26/175 [14.7%] vs 44/175 [25.1%]; relative risk, 0.58; 95% confidence interval 0.38-0.90; p=0.01). The preterm premature rupture of membranes rate was significantly lower in pessary carriers (4/177 [2.3%] vs. 14/175 [8.0%]; relative risk, 0.28; 95% confidence interval 0.09-0.84; p=0.01). The pessary group less frequently required readmission for new threatened preterm labor episodes (8/177 [4.5%] vs. 35/175 [20.0%]; relative risk, 0.23; 95% confidence interval, 0.11-0.47; p<0.0001. No serious adverse maternal events occurred; neonatal morbidity and mortality were similar in both groups. Pessary use did not significantly lower the spontaneous preterm birth rate before 34 weeks in women with a short cervix remaining after a threatened preterm labor episode but did significantly reduce the spontaneous preterm birth rate before 37 weeks, threatened preterm labor recurrence and the preterm premature rupture of membranes rate. Copyright © 2018 Elsevier Inc. All rights reserved.

Evaluation of plasma C-reactive protein levels in pregnant women with and without periodontal disease: A comparative study.

PubMed

Sharma, Anupriya; Ramesh, Amitha; Thomas, Biju

2009-09-01

Circulating C-reactive protein (CRP) levels are a marker of systemic inflammation and are associated with periodontal disease, a chronic bacterial infection associated with elevation of proinflammatory cytokines and prostaglandins. CRP has been associated with adverse pregnancy outcomes, including preterm delivery, preeclampsia, and intrauterine growth restriction. Furthermore, periodontal disease has been associated with increased risk of preterm low birth weight, low birth weight, and preterm birth. The present study was conducted to assess plasma CRP levels in pregnant women with and without periodontal disease; to evaluate the effect of periodontal therapy on the incidence of preterm delivery; and to compare the incidence of preterm delivery in pregnant women with and without periodontal disease. A total of 90 pregnant women aged between 18-35 years with gestational age between 12-28 weeks were recruited and divided into three equal groups (control group, study group, treatment group) of 30 each. Blood samples were taken for estimation of C-reactive protein levels from all groups at 12-20 weeks of gestation, determined using ultrasensitive turbidimetric immunoassay (QUANTIA-CRP US). The treatment group comprised plaque control, scaling, and root planning and daily rinsing with 0.2% chlorhexidine mouth before 28 weeks of gestation. The mean value of C-reactive protein levels in subjects with periodontal disease was higher compared to control group i.e., 1.20 +/- 0.247 mg/dl and 1.22 +/- 0.250 mg/dl, respectively, compared to 0.713 +/- 0.139 mg/ dl (P = 0.001). The mean value of CRP levels before treatment was greater than the mean value after treatment i.e., 1.22 +/- 0.25 compared to 0.84 +/- 0.189 (P < 0.001). The incidence of preterm delivery (< 37 weeks) was 31.7% in the periodontal disease group (study group) compared to 8.3% in the control group (P = 0.001). The incidence of preterm delivery in the treatment group was 15.0% compared to 31.7% in the nontreatment group (study group). The findings from the study suggest that periodontal disease in pregnant women is associated with increased C- reactive protein levels in early pregnancy, incidence of preterm delivery is higher in pregnant women with periodontal disease compared to healthy controls, periodontal therapy during pregnancy reduces plasma CRP levels and there is decrease in incidence of preterm delivery after periodontal therapy.

Birth Outcomes of Latin Americans in Two Countries with Contrasting Immigration Admission Policies: Canada and Spain

PubMed Central

Urquia, Marcelo L.

2015-01-01

Background We delved into the selective migration hypothesis on health by comparing birth outcomes of Latin American immigrants giving birth in two receiving countries with dissimilar immigration admission policies: Canada and Spain. We hypothesized that a stronger immigrant selection in Canada will reflect more favourable outcomes among Latin Americans giving birth in Canada than among their counterparts giving birth in Spain. Materials and Methods We conducted a cross-sectional bi-national comparative study. We analyzed birth data of singleton infants born in Canada (2000–2005) (N = 31,767) and Spain (1998–2007) (N = 150,405) to mothers born in Spanish-speaking Latin American countries. We compared mean birthweight at 37–41 weeks gestation, and low birthweight and preterm birth rates between Latin American immigrants to Canada vs. Spain. Regression analysis for aggregate data was used to obtain Odds Ratios and Mean birthweight differences adjusted for infant sex, maternal age, parity, marital status, and father born in same source country. Results Latin American women in Canada had heavier newborns than their same-country counterparts giving birth in Spain, overall [adjusted mean birthweight difference: 101 grams; 95% confidence interval (CI): 98, 104], and within each maternal country of origin. Latin American women in Canada had fewer low birthweight and preterm infants than those giving birth in Spain [adjusted Odds Ratio: 0.88; 95% CI: 0.82, 0.94 for low birthweight, and 0.88; 95% CI: 0.84, 0.93 for preterm birth, respectively]. Conclusion Latin American immigrant women had better birth outcomes in Canada than in Spain, suggesting a more selective migration in Canada than in Spain. PMID:26308857

Correlates of birth asphyxia using two Apgar score classification methods.

PubMed

Olusanya, Bolajoko O; Solanke, Olumuyiwa A

2010-01-01

Birth asphyxia is commonly indexed by low five-minute Apgar scores especially in resource-constrained settings but the impact of different classification thresholds on the associated risk factors has not been reported. To determine the potential impact of two classification methods of five-minute Apgar score as predictor for birth asphyxia. A cross-sectional study of preterm and term survivors in Lagos, Nigeria in which antepartum and intrapartum factors associated with "very low" (0-3) or "intermediate" (4-6) five-minute Apgar scores were compared with correlates of low five-minute Apgar scores (0-6) based on multinomial and binary logistic regression analyses. Of the 4281 mother-infant pairs enrolled, 3377 (78.9%) were full-term and 904 (21.1%) preterm. Apgar scores were very low in 99 (2.3%) and intermediate in 1115 (26.0%). Antenatal care, premature rupture of membranes (PROM), hypertensive disorders and mode of delivery were associated with very low and intermediate Apgar scores in all infants. Additionally, parity, antepartum haemorrhage and prolonged/obstructed labour (PROL) were predictive in term infants compared with maternal occupation and intrauterine growth restriction (IUGR) in preterm infants. Conversely, PROM in term infants and maternal occupation in preterm infants were not significantly associated with the composite low Apgar scores (0-6) while IUGR was associated with term infants. Predictors of birth asphyxia in preterm and term infants are likely to be affected by the Apgar score classification method adopted and the clinical implications for optimal resuscitation practices merit attention in resource-constrained settings.

Small fetal thymus and adverse obstetrical outcome: a systematic review and a meta-analysis.

PubMed

Caissutti, Claudia; Familiari, Alessandra; Khalil, Asma; Flacco, Maria E; Manzoli, Lamberto; Scambia, Giovanni; Cagnacci, Angelo; D'antonio, Francesco

2018-02-01

The aim of this study was to explore the association between small fetal thymus on ultrasound and adverse obstetrical outcome. Medline, Embase, Cochrane and Web of Science databases were searched. Primary outcome was the risk of preterm birth before 37 and 34 weeks of gestation in fetuses with, compared to those without, a small thymus on ultrasound. occurrence of chorioamnionitis, intrauterine growth restriction, neonatal sepsis, gestational age at birth, birthweight, neonatal morbidity and preeclampsia. Twelve studies including 1744 fetuses who had ultrasound assessment of thymus during pregnancy were included. Women with preterm premature rupture of the membranes or with preterm labor were at higher risk of preterm birth before 37 weeks (p = 0.01), or before 34 weeks (p < 0.001) for fetuses with a small fetal thymus compared to those without a small thymus, and the risk of chorioamnionitis was higher when the thymus was small (p < 0.001). Fetuses with small thymus were not at higher risk of intrauterine growth restriction (p = 0.3). A small thymus increased the risk of neonatal sepsis (p = 0.007) and morbidity (p = 0.003), but not the risk of preeclampsia (p = 0.9). A small fetal thymus is associated with a higher risk of preterm birth, chorioamnionitis, neonatal sepsis and morbidity, but not with intrauterine growth restriction and preeclampsia. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

Prediction of preterm birth in twin gestations using biophysical and biochemical tests

PubMed Central

Conde-Agudelo, Agustin; Romero, Roberto

2018-01-01

The objective of this study was to determine the performance of biophysical and biochemical tests for the prediction of preterm birth in both asymptomatic and symptomatic women with twin gestations. We identified a total of 19 tests proposed to predict preterm birth, mainly in asymptomatic women. In these women, a single measurement of cervical length with transvaginal ultrasound before 25 weeks of gestation appears to be a good test to predict preterm birth. Its clinical potential is enhanced by the evidence that vaginal progesterone administration in asymptomatic women with twin gestations and a short cervix reduces neonatal morbidity and mortality associated with spontaneous preterm delivery. Other tests proposed for the early identification of asymptomatic women at increased risk of preterm birth showed minimal to moderate predictive accuracy. None of the tests evaluated in this review meet the criteria to be considered clinically useful to predict preterm birth among patients with an episode of preterm labor. However, a negative cervicovaginal fetal fibronectin test could be useful in identifying women who are not at risk for delivering within the next week, which could avoid unnecessary hospitalization and treatment. This review underscores the need to develop accurate tests for predicting preterm birth in twin gestations. Moreover, the use of interventions in these patients based on test results should be associated with the improvement of perinatal outcomes. PMID:25072736

Prediction of preterm birth in twin gestations using biophysical and biochemical tests.

PubMed

Conde-Agudelo, Agustin; Romero, Roberto

2014-12-01

The objective of this study was to determine the performance of biophysical and biochemical tests for the prediction of preterm birth in both asymptomatic and symptomatic women with twin gestations. We identified a total of 19 tests proposed to predict preterm birth, mainly in asymptomatic women. In these women, a single measurement of cervical length with transvaginal ultrasound before 25 weeks of gestation appears to be a good test to predict preterm birth. Its clinical potential is enhanced by the evidence that vaginal progesterone administration in asymptomatic women with twin gestations and a short cervix reduces neonatal morbidity and mortality associated with spontaneous preterm delivery. Other tests proposed for the early identification of asymptomatic women at increased risk of preterm birth showed minimal to moderate predictive accuracy. None of the tests evaluated in this review meet the criteria to be considered clinically useful to predict preterm birth among patients with an episode of preterm labor. However, a negative cervicovaginal fetal fibronectin test could be useful in identifying women who are not at risk for delivering within the next week, which could avoid unnecessary hospitalization and treatment. This review underscores the need to develop accurate tests for predicting preterm birth in twin gestations. Moreover, the use of interventions in these patients based on test results should be associated with the improvement of perinatal outcomes. Copyright © 2014. Published by Elsevier Inc.

Preventing preterm births: trends and potential reductions with current interventionsin 39 very high human development index countries

PubMed Central

Chang, Hannah H.; Larson, Jim; Blencowe, Hannah; Spong, Catherine Y.; Howson, Christopher P.; Cairns-Smith, Sarah; Lackritz, Eve M.; Lee, Shoo K.; Mason, Elizabeth; Serazin, Andrew C.; Walani, Salimah; Simpson, Joe Leigh; Lawn, Joy E.

2013-01-01

Summary Background Each year,1.1 million babies die from prematurity, andmany survivors are disabled. Worldwide, 15 million babies are preterm(<37 weeks’ gestation),withtwo decades of increasing ratesinalmost all countries with reliable data. Improved care of babies has reduced mortality in high-income countries, although effective interventions have yet to be scaled-up in most low-income countries. A 50% reduction goal for preterm-specific mortality by 2025 has been set in the “Born Too Soon” report. However, for preterm birth prevention,understanding of drivers and potential impact of preventive interventions is limited. We examine trends and estimate the potential reduction in preterm birthsforvery high human development index (VHHDI) countries if current evidence-based interventions were widely implemented. This analysis is to inform a “Born Too Soon” rate reduction target. Methods Countries were assessed for inclusion based on availability and quality ofpreterm prevalence data (2000-2010), and trend analyses with projections undertaken. We analysed drivers of rate increases in the USA, 1998-2004. For 39 VHHDI countrieswith >10,000 births, country-by-country analyses were performed based on target population, incremental coverage increase,and intervention efficacy. Cost savings were estimated based on reported costs for preterm care in the USAadjusted usingWorld Bank purchasing power parity. Findings From 2010, even if all VHHDI countries achieved annual preterm birth rate reductions of the best performers, (Sweden and Netherlands), 2000-2010 or 2005-2010(Lithuania, Estonia)), rates would experience a relative reduction of<5% by 2015 on average across the 39 countries.Our analysis of preterm birth rise 1998-2004 in USA suggests half the change is unexplained, but important drivers includeinductions/cesareandelivery and ART.For all 39 VHHDI countries, five interventionsmodeling at high coveragepredicted 5%preterm birth rate relative reduction from 9.59 to 9.07% of live births:smoking cessation (0.01 rate reduction), decreasing multiple embryo transfers during assisted reproductive technologies (0.06), cervical cerclage (0.15), progesterone supplementation (0.01), and reduction of non-medically indicated labour induction or caesarean delivery (0.29).These translate to 58,000 preterm births averted and total annual economic cost savings of ~US$ 3 billion. Interpretation Even with optimal coverage of current interventions, many being complex to implement, the estimated potential reduction in preterm birth is tiny. Hence we recommenda conservative target of 5% preterm birth rate relative reductionby 2015. Our findings highlight the urgent need for discovery research into underlying mechanisms of preterm birth, and developmentof innovative interventions. Furthermore, the highest preterm birth rates occur in low-income settings where the causes of prematurity may differand have simpler solutions, such as birth spacing and treatment of infections in pregnancy. Urgent focus on these settings also is critical to reduce preterm births worldwide. PMID:23158883

Cerebral Perfusion Is Perturbed by Preterm Birth and Brain Injury.

PubMed

Mahdi, E S; Bouyssi-Kobar, M; Jacobs, M B; Murnick, J; Chang, T; Limperopoulos, C

2018-05-10

Early disturbances in systemic and cerebral hemodynamics are thought to mediate prematurity-related brain injury. However, the extent to which CBF is perturbed by preterm birth is unknown. Our aim was to compare global and regional CBF in preterm infants with and without brain injury on conventional MR imaging using arterial spin-labeling during the third trimester of ex utero life and to examine the relationship between clinical risk factors and CBF. We prospectively enrolled preterm infants younger than 32 weeks' gestational age and <1500 g and performed arterial spin-labeling MR imaging studies. Global and regional CBF in the cerebral cortex, thalami, pons, and cerebellum was quantified. Preterm infants were stratified into those with and without structural brain injury. We further categorized preterm infants by brain injury severity: moderate-severe and mild. We studied 78 preterm infants: 31 without brain injury and 47 with brain injury (29 with mild and 18 with moderate-severe injury). Global CBF showed a borderline significant increase with increasing gestational age at birth ( P = .05) and trended lower in preterm infants with brain injury ( P = .07). Similarly, regional CBF was significantly lower in the right thalamus and midpons ( P < .05) and trended lower in the midtemporal, left thalamus, and anterior vermis regions ( P < .1) in preterm infants with brain injury. Regional CBF in preterm infants with moderate-severe brain injury trended lower in the midpons, right cerebellar hemisphere, and dentate nuclei compared with mild brain injury ( P < .1). In addition, a significant, lower regional CBF was associated with ventilation, sepsis, and cesarean delivery ( P < .05). We report early disturbances in global and regional CBF in preterm infants following brain injury. Regional cerebral perfusion alterations were evident in the thalamus and pons, suggesting regional vulnerability of the developing cerebro-cerebellar circuitry. © 2018 by American Journal of Neuroradiology.

Preterm birth disrupts cerebellar development by affecting granule cell proliferation program and Bergmann glia.

PubMed

Iskusnykh, Igor Y; Buddington, Randal K; Chizhikov, Victor V

2018-08-01

Preterm birth is a leading cause of long-term motor and cognitive deficits. Clinical studies suggest that some of these deficits result from disruption of cerebellar development, but the mechanisms that mediate cerebellar abnormalities in preterm infants are largely unknown. Furthermore, it remains unclear whether preterm birth and precocious exposure to the ex-utero environment directly disrupt cerebellar development or indirectly by increasing the probability of cerebellar injury, including that resulting from clinical interventions and protocols associated with the care of preterm infants. In this study, we analyzed the cerebellum of preterm pigs delivered via c-section at 91% term and raised for 10 days, until term-equivalent age. The pigs did not receive any treatments known or suspected to affect cerebellar development and had no evidence of brain damage. Term pigs sacrificed at birth were used as controls. Immunohistochemical analysis revealed that preterm birth did not affect either size or numbers of Purkinje cells or molecular layer interneurons at term-equivalent age. The number of granule cell precursors and Bergmann glial fibers, however, were reduced in preterm pigs. Preterm pigs had reduced proliferation but not differentiation of granule cells. qRT-PCR analysis of laser capture microdissected external granule cell layer showed that preterm pigs had a reduced expression of Ccnd1 (Cyclin D1), Ccnb1 (Cyclin B1), granule cell master regulatory transcription factor Atoh1, and signaling molecule Jag1. In vitro rescue experiments identified Jag1 as a central granule cell gene affected by preterm birth. Thus, preterm birth and precocious exposure to the ex-utero environment disrupt cerebellum by modulating expression of key cerebellar developmental genes, predominantly affecting development of granule precursors and Bergmann glia. Copyright © 2018 Elsevier Inc. All rights reserved.

Repeat antenatal glucocorticoids for women at risk of preterm birth: a Cochrane Systematic Review.

PubMed

McKinlay, Christopher J D; Crowther, Caroline A; Middleton, Philippa; Harding, Jane E

2012-03-01

Administration of antenatal glucocorticoids to women at risk of preterm birth has major benefits for infants but the use of repeat dose(s) is controversial. We performed a systematic review of randomized trials, using standard Cochrane methodology, to assess the effectiveness and safety of 1 or more repeat doses given to women at risk of preterm birth 7 or more days after an initial course. Ten trials were included involving over 4730 women and 5700 infants. Treatment with repeat dose(s) compared with no repeat treatment reduced the risk of respiratory distress syndrome (risk ratio, 0.83; 95% confidence interval, 0.75-0.91) and serious neonatal morbidity (risk ratio, 0.84; 95% confidence interval, 0.75-0.94). At 2- to 3-year follow-up (4 trials, 4170 children), there was no evidence of either significant benefit or harm. Repeat doses of glucocorticoids should be considered in women at risk of preterm birth 7 or more days after an initial course, in view of the neonatal benefits. Copyright © 2012 Mosby, Inc. All rights reserved.

[Risk factors for preterm labor].

PubMed

Rodrigues, T; Barros, H

1998-10-01

Most studies investigating preterm risk factors include medically induced preterm labor due to fetal or maternal complications and do not distinguish preterm labor from preterm premature rupture of membranes. Thus, the objective of this study was to determine the proportion of the three types of preterm birth and identify risk factors for spontaneous preterm labor in a sample of pregnant women who delivered at two level III units. From January to October 1996, we interviewed 385 women with live preterm newborns and, as controls, 357 mothers of term newborns. Preterm births were classified as preterm labor, preterm premature rupture of membranes and iathrogenic preterm. Independent associations between maternal sociodemographic, constitutional, nutritional and obstetric characteristics and preterm labor were identified using logistic regression analysis. In this sample of preterm births, 29% corresponded to preterm labor, 49% to preterm premature rupture of the membranes and 22% were iathrogenic preterm. The identified risk factors for preterm labor were multiple gestation, no paid work during pregnancy, less than six prenatal care visits, arm circumference less than 26 cm and previous preterm or low birth-weight. Gestational bleeding during the first or third trimester was significantly associated with preterm labor. As previously recognized, multiple gestation, prior preterm or low birthweight and gestational bleeding are established risk factors for preterm labor. However, prenatal care, maternal work and nutritional status have also been revealed as important issues in preterm risk, deserving special interest since they are susceptible to preventive intervention.

Periodontal treatment during pregnancy and birth outcomes: a meta-analysis of randomised trials.

PubMed

George, Ajesh; Shamim, Simin; Johnson, Maree; Ajwani, Shilpi; Bhole, Sameer; Blinkhorn, Anthony; Ellis, Sharon; Andrews, Karen

2011-06-01

The objective of this review was to conduct a meta-analysis of all up-to-date randomised control trials to determine whether periodontal treatment during pregnancy has the potential of reducing preterm birth and low birth weight incidence. Bibliographic databases MEDLINE (1966-present), EMBASE (1980-present), CINAHL (1982-present) and the Cochrane library up to and including 2010 Issue 10 were searched. The reference list of included studies and reviews were also searched for additional literature. Eligible studies were, published and ongoing randomised control trials that compared pregnancy outcomes for pregnant women who received periodontal treatment during the prenatal period. Two of the investigators independently assessed the studies and then extracted and summarised data from eligible trials. Extracted data were entered into Review Manager software and analysed. A total of 5645 pregnant women participated in the 10 eligible trials. Meta-analysis found that periodontal treatment significantly lowered preterm birth (odd ratio 0.65; 95% confidence interval, 0.45-0.93; P = 0.02) and low birth weight (odd ratio 0.53; 95% confidence interval, 0.31-0.92; P = 0.02) rates while no significant difference was found for spontaneous abortion/stillbirth (odd ratio 0.71; 95% confidence interval, 0.43-1.16; P = 0.17). Moderate heterogeneity was observed among the studies for preterm birth and low birth weight. Subgroup analysis showed significant effect of periodontal treatment in pregnant women with low rate of previous preterm birth/low birth weight (odd ratio 0.35; 95% confidence interval, 017-0.70; P = 0.003) and less severe periodontal disease (odd ratio 0.49; confidence interval, 028-0.87; P = 0.01) as defined by probing depth. The cumulative evidence suggests that periodontal treatment during pregnancy may reduce preterm birth and low birth weight incidence. However, these findings need to be further validated through larger more targeted randomised control trials. © 2011 The Authors. International Journal of Evidence-Based Healthcare © 2011 The Joanna Briggs Institute.

Maternal tea consumption and the risk of preterm delivery in urban China: a birth cohort study.

PubMed

Huang, Lei; Lerro, Catherine; Yang, Tao; Li, Jing; Qiu, Jie; Qiu, Weitao; He, Xiaochun; Cui, Hongmei; Lv, Ling; Xu, Ruifeng; Xu, Xiaoying; Huang, Huang; Liu, Qing; Zhang, Yawei

2016-05-31

Studies investigating the relationship between maternal tea drinking and risk of preterm birth have reached inconsistent results. The present study analyzed data from a birth cohort study including 10,179 women who delivered a singleton live birth were conducted in Lanzhou, China between 2010 and 2012. Drinking tea (OR = 1.36, 95 % CI: 1.09-1.69), and specifically green (OR = 1.42, 95 % CI: 1.08-1.85) or scented tea (OR = 1.61, 95 % CI: 1.04-2.50), was associated with an increased risk of preterm birth. Drinking tea was associated with both moderate preterm (OR = 1.41, 95 % CI: 1.12-1.79) and spontaneous preterm birth (OR = 1.41, 95 % CI: 1.09-1.83). Risk of preterm birth increased with decreasing age of starting tea drinking (<20 years, OR = 1.60, 95 % CI: 1.17-2.20) and increasing duration (p for trend < 0.01). The relationship between tea drinking and preterm birth is modified by both maternal age (p < 0.05) and gestational weight gain (p < 0.05). Despite conflicting findings in the previous literature, we saw a significant association with maternal tea drinking and risk of preterm birth in our cohort. More studies are needed both to confirm this finding and to elucidate the mechanism behind this association.

Socioeconomic inequality in preterm birth in four Brazilian birth cohort studies.

PubMed

Sadovsky, Ana Daniela Izoton de; Matijasevich, Alicia; Santos, Iná S; Barros, Fernando C; Miranda, Angelica Espinosa; Silveira, Mariangela Freitas

To analyze economic inequality (absolute and relative) due to family income in relation to the occurrence of preterm births in Southern Brazil. Four birth cohort studies were conducted in the years 1982, 1993, 2004, and 2011. The main exposure was monthly family income and the primary outcome was preterm birth. The inequalities were calculated using the slope index of inequality and the relative index of inequality, adjusted for maternal skin color, education, age, and marital status. The prevalence of preterm births increased from 5.8% to approximately 14% (p-trend<0.001). Late preterm births comprised the highest proportion among the preterm births in all studies, although their rates decreased over the years. The analysis on the slope index of inequality demonstrated that income inequality arose in the 1993, 2004, and 2011 studies. After adjustment, only the 2004 study maintained the difference between the poorest and the richest subjects, which was 6.3 percentage points. The relative index of inequality showed that, in all studies, the poorest mothers were more likely to have preterm newborns than the richest. After adjustment for confounding factors, it was observed that the poorest mothers only had a greater chance of this outcome in 2004. In a final model, economic inequalities resulting from income were found in relation to preterm births only in 2004, although a higher prevalence of prematurity continued to be observed in the poorest population, in all the studies. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Overweight and obesity in mothers and risk of preterm birth and low birth weight infants: systematic review and meta-analyses

PubMed Central

Han, Zhen; Mulla, Sohail; Beyene, Joseph

2010-01-01

Objective To determine the relation between overweight and obesity in mothers and preterm birth and low birth weight in singleton pregnancies in developed and developing countries. Design Systematic review and meta-analyses. Data sources Medline and Embase from their inceptions, and reference lists of identified articles. Study selection Studies including a reference group of women with normal body mass index that assessed the effect of overweight and obesity on two primary outcomes: preterm birth (before 37 weeks) and low birth weight (<2500 g). Data extraction Two assessors independently reviewed titles, abstracts, and full articles, extracted data using a piloted data collection form, and assessed quality. Data synthesis 84 studies (64 cohort and 20 case-control) were included, totalling 1 095 834 women. Although the overall risk of preterm birth was similar in overweight and obese women and women of normal weight, the risk of induced preterm birth was increased in overweight and obese women (relative risk 1.30, 95% confidence interval 1.23 to 1.37). Although overall the risk of having an infant of low birth weight was decreased in overweight and obese women (0.84, 0.75 to 0.95), the decrease was greater in developing countries than in developed countries (0.58, 0.47 to 0.71 v 0.90, 0.79 to 1.01). After accounting for publication bias, the apparent protective effect of overweight and obesity on low birth weight disappeared with the addition of imputed “missing” studies (0.95, 0.85 to 1.07), whereas the risk of preterm birth appeared significantly higher in overweight and obese women (1.24, 1.13 to 1.37). Conclusions Overweight and obese women have increased risks of preterm birth and induced preterm birth and, after accounting for publication bias, appeared to have increased risks of preterm birth overall. The beneficial effects of maternal overweight and obesity on low birth weight were greater in developing countries and disappeared after accounting for publication bias. PMID:20647282

Preterm Birth and its Impact on Renal Health.

PubMed

Luyckx, Valerie A

2017-07-01

Preterm birth occurs in approximately 10% of all births worldwide. Preterm infants have reduced nephron numbers at birth in proportion to gestational age, and are at increased risk of neonatal acute kidney injury as well as higher blood pressure, proteinuria, and chronic kidney disease later in life. Rapid catch-up growth in preterm infants, especially if resulting in obesity, is a risk factor for end-stage kidney disease among children with proteinuric renal disease. Preterm birth, however, is a risk factor not only for the infant because mothers who deliver preterm have an increased risk of having subsequent preterm deliveries as well as hypertension, cardiovascular disease, and renal disease later in life. Preterm birth in a female infant is also a risk factor for her future risk of having a preterm delivery, gestational hypertension, and gestational diabetes, which in turn may impact the development of fetal kidneys and the offspring's risk of hypertension and renal disease. This intergenerational programming cycle, therefore, perpetuates the risks and consequences of prematurity. Interruption of this cycle may be possible through optimization of maternal nutrition and health as well as careful antenatal care, which may in turn reduce the global burden of hypertension and renal disease in subsequent generations. Copyright © 2017 Elsevier Inc. All rights reserved.

Use of microbial cultures and antibiotics in the prevention of infection-associated preterm birth.

PubMed

Klein, Laura L; Gibbs, Ronald S

2004-06-01

The purpose of this study was to summarize recent evidence regarding infection-associated preterm birth and to make appropriate recommendations. Antepartum treatment of lower genital tract infection or bacterial colonization has been found to reduce the incidence of preterm birth in the case of asymptomatic bacteriuria and bacterial vaginosis in selected patients but has been proved to be ineffective for vaginal colonization with organisms such as Ureaplasma urealyticum and group B streptococcus. This is a clinical opinion based on a review of recent data related to 1) the association between lower genital tract infection and preterm birth and 2) antibiotic trials to prevent preterm birth. Antepartum treatment of lower genital tract infection or bacterial colonization has been found to reduce the incidence of preterm birth in the case of asymptomatic bacteriuria and bacterial vaginosis in selected patients, but has been proven to be ineffective for vaginal colonization with organisms such as Ureaplasma urealyticum and group B streptococcus. Large well-designed trials have shown that the routine administration of antibiotics to women with preterm labor and intact membranes is not beneficial; however, antibiotic regimens including macrolides are recommended for preterm premature rupture of the membranes. Large well-designed trials have shown that the routine administration of antibiotics to women with preterm labor and intact membranes is not beneficial; however, antibiotic regimens that include macrolides are recommended for preterm premature rupture of the membranes.

Socioeconomic and Environmental Determinants to Preterm Birth in Tibetan Women: An Analysis Based on the Hierarchically Conceptual Frame.

PubMed

Fan, Xiao-Jing; Gao, Jian-Min; Kang, Yi-Jun; Dang, Shao-Nong; Wang, Wei-Hua; Yan, Hong; Wang, Duo-Lao

2017-10-05

Preterm birth is a common cause of death in newborns and may result from many determinants, but evidence for the socioeconomic and environmental determinants of preterm birth in Tibetan women of childbearing age is limited. The aim of this study was to understand the current status of preterm birth in native Tibetan women and investigate the socioeconomic and environmental determinants. Data were drawn from a cohort study which was conducted from August 2006 to August 2012 in rural Lhasa, Tibet, China. A total of 1419 Tibetan pregnant women were followed from 20 weeks' gestation until delivery; the loss to follow-up rate was 4.69%. The incidence of preterm birth was estimated to show the status of preterm births in Tibet. Logistic regression models for longitudinal data were established, and odds ratios (ORs) together with 95% confidence intervals (CIs) were used to evaluate the association between the occurrence of preterm birth and 16 selected potential determinants based on the hierarchical conceptual frame. The incidence of preterm birth was 4.58% (95% CI = 3.55-5.80%). After adjusting for health-related variables of the mothers and newborns, socioeconomic and environmental determinants associated with preterm birth included season (spring: OR = 0.28, 95% CI = 0.09-0.84; autumn: OR = 0.21, 95% CI = 0.06-0.69; and winter: OR = 0.31, 95% CI = 0.12-0.82) and calendar year of delivery (2010: OR = 5.03, 95% CI = 1.24-20.35; 2009: OR = 6.62, 95% CI = 1.75-25.10; and 2007-2008: OR = 5.93, 95% CI = 1.47-23.90). The incidence of preterm birth among native Tibetan women was low and there was a decreasing trend in recent years; however, it is still essential to strengthen seasonal maternal care, extend the spacing between pregnancies, and reinforce adequate maternal nutrition.

Effect of periodontal treatment on preterm birth rate: a systematic review of meta-analyses.

PubMed

López, Néstor J; Uribe, Sergio; Martinez, Benjamín

2015-02-01

Preterm birth is a major cause of neonatal morbidity and mortality in both developed and developing countries. Preterm birth is a highly complex syndrome that includes distinct clinical subtypes in which many different causes may be involved. The results of epidemiological, molecular, microbiological and animal-model studies support a positive association between maternal periodontal disease and preterm birth. However, the results of intervention studies carried out to determine the effect of periodontal treatment on reducing the risk of preterm birth are controversial. This systematic review critically analyzes the methodological issues of meta-analyses of the studies to determine the effect of periodontal treatment to reduce preterm birth. The quality of the individual randomized clinical trials selected is of highest relevance for a systematic review. This article describes the methodological features that should be identified a priori and assessed individually to determine the quality of a randomized controlled trial performed to evaluate the effect of periodontal treatment on pregnancy outcomes. The AMSTAR and the PRISMA checklist tools were used to assess the quality of the six meta-analyses selected, and the bias domain of the Cochrane Collaboration's Tool was applied to evaluate each of the trials included in the meta-analyses. In addition, the methodological characteristics of each clinical trial were assessed. The majority of the trials included in the meta-analyses have significant methodological flaws that threaten their internal validity. The lack of effect of periodontal treatment on preterm birth rate concluded by four meta-analyses, and the positive effect of treatment for reducing preterm birth risk concluded by the remaining two meta-analyses are not based on consistent scientific evidence. Well-conducted randomized controlled trials using rigorous methodology, including appropriate definition of the exposure, adequate control of confounders for preterm birth and application of effective periodontal interventions to eliminate periodontal infection, are needed to confirm the positive association between periodontal disease and preterm birth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Birth Outcomes Among Adolescent and Young Adult Cancer Survivors.

PubMed

Anderson, Chelsea; Engel, Stephanie M; Mersereau, Jennifer E; Black, Kristin Z; Wood, William A; Anders, Carey K; Nichols, Hazel B

2017-08-01

Cancer diagnosis and treatment may adversely affect reproductive outcomes among female cancer survivors. To compare the birth outcomes of adolescent and young adult cancer survivors (AYA [diagnosed at ages 15-39 years]) with those of women without a cancer diagnosis. The North Carolina Central Cancer Registry (CCR) was used to identify female AYA cancer survivors diagnosed from January 2000 to December 2013; CCR records were linked to statewide birth certificate files from January 2000 to December 2014 to identify postdiagnosis live births to AYA survivors (n = 2598). A comparison cohort of births to women without a recorded cancer diagnosis was randomly selected from birth certificate files (n = 12 990) with frequency matching on maternal age and year of delivery. Prevalence of preterm birth, low birth weight, small-for-gestational-age births, cesarean delivery, and low Apgar score. Overall, 2598 births to AYA cancer survivors (mean [SD] maternal age, 31 [5] years) were included. Births to AYA cancer survivors had a significantly increased prevalence of preterm birth (prevalence ratio [PR], 1.52; 95% CI, 1.34-1.71), low birth weight (PR, 1.59; 95% CI, 1.38-1.83), and cesarean delivery (PR, 1.08; 95% CI, 1.01-1.14) relative to the comparison cohort of 1299. The higher prevalence of these outcomes was most concentrated among births to women diagnosed during pregnancy. Other factors associated with preterm birth and low birth weight included treatment with chemotherapy and a diagnosis of breast cancer, non-Hodgkin lymphoma, or gynecologic cancers. The prevalence of small-for-gestational-age births and low Apgar score (<7) did not differ significantly between groups. Live births to AYA cancer survivors may have an increased risk of preterm birth and low birth weight, suggesting that additional surveillance of pregnancies in this population is warranted. Our findings may inform the reproductive counseling of female AYA cancer survivors.

Predictors of preterm birth in patients with mild systemic lupus erythematosus.

PubMed

Clowse, Megan E B; Wallace, Daniel J; Weisman, Michael; James, Andra; Criscione-Schreiber, Lisa G; Pisetsky, David S

2013-09-01

While increased disease activity is the best predictor of preterm birth in women with systemic lupus erythematosus (SLE), even women with low disease activity are at increased risk of this complication. Biomarkers that would identify at-risk pregnancies could allow interventions to prevent preterm birth. Measures of SLE activity, inflammation, placental health and renal function between 20 and 28 weeks gestation (mid-gestation) were correlated to preterm birth and gestational age at delivery in a prospective cohort of pregnant women with SLE. Of the 40 pregnancies in 39 women, all with mild-moderate SLE disease, 9 (23.7%) of the 38 live births were delivered preterm. Low C4 was the only marker of SLE activity associated with younger gestational age at delivery. Elevated ferritin and lower oestradiol correlated with younger gestational age at delivery. Renal function remained normal during all pregnancies at mid-gestation and did not correlate with preterm birth. Higher serum uric acid, however, correlated with younger gestational age at delivery. In women with SLE with mild-moderate disease activity, ferritin, oestradiol and uric acid levels at mid-gestation may predict preterm birth. These markers may prove to be clinically useful in identifying pregnancies at particularly high risk for adverse outcomes.

Understanding the role of violence as a social determinant of preterm birth.

PubMed

Masho, Saba W; Cha, Susan; Chapman, Derek A; Chelmow, David

2017-02-01

Preterm birth is one of the leading causes of infant morbidity and mortality. Although major strides have been made in identifying risk factors for preterm birth, the complexities between social and individual risk factors are not well understood. This study examines the association between neighborhood youth violence and preterm birth. A 10-year live birth registry data set (2004 through 2013) from Richmond, VA, a mid-sized, racially diverse city, was analyzed (N = 27,519). Data were geocoded and merged with census tract and police report data. Gestational age at birth was classified as <32 weeks, 32-36 weeks, and term ≥37 weeks. Using police report data, youth violence rates were calculated for each census tract area and categorized into quartiles. Hierarchical models were examined fitting multilevel logistic regression models incorporating randomly distributed census tract-specific intercepts assuming a binary distribution and a logit link function. Nearly a fifth of all births occurred in areas with the highest quartiles of violence. After adjusting for maternal age, race/ethnicity, education, paternal presence, parity, adequacy of prenatal care, pregnancy complications, history of preterm birth, insurance, and tobacco, alcohol, and drug use, census tracts with the highest level of violence had 38% higher odds of very preterm births (adjusted odds ratio, 1.38; 95% confidence interval, 1.06-1.80), than census tracts with the lowest level of violence. There is an association between high rate of youth violence and very preterm birth. Findings from this study may help inform future research to develop targeted interventions aimed at reducing community violence and very preterm birth in vulnerable populations. Copyright © 2016 Elsevier Inc. All rights reserved.

The Growing Trend of Moderate Preterm Births: An Ecological Study in One Region of Brazil.

PubMed

Oliveira, Rosana Rosseto de; Melo, Emiliana Cristina; Falavina, Larissa Pereira; Mathias, Thais Aidar de Freitas

2015-01-01

Preterm birth is a serious public health problem, as it is linked to high rates of neonatal and child morbidity and mortality, with Brazil listed among the countries with the ten highest numbers of premature births. Nonetheless, knowledge is scarce regarding prematurity and associated factors in mid-sized cities. The objective of this study was to analyze the trend of preterm births and associated factors in a municipality located in the state of Paraná, Brazil. This was an ecological time series study of births recorded into the Live Birth Information System for residents of Maringá, Paraná, Brazil, between 2000 and 2013. The polynomial regression model was used for trend analysis of preterm birth, characteristics of the mother, gestation and delivery, and newborn. The association with preterm birth was analyzed using odds ratio (OR). A total of 61,634 live births were analyzed, of which 5,632 were preterm births. Prematurity increased from 7.9% in 2000 to 11.2% in 2013 -an average increase of 0.54% per year (r2 = 0.93)-with a growing share of moderate preterm births (32 to <37 weeks), which rose from 7.0% in 2000 to 9.7% in 2013. Between 2011 and 2013, multiple pregnancy (OR = 16.64; CI = 13.24-20.92), inadequate number of prenatal visits (OR = 2.81; CI = 2.51-3.15), Apgar score below 7 at 1 (OR = 4.07; CI = 3.55-4.67) and 5 minutes (OR = 10.88; CI = 7.71-15.36), low birth weight (OR = 38.75; CI = 33.72-44.55) and congenital malformations (OR = 3.18; CI = 2.14-4.74) were associated with preterm birth. A growing trend was observed for multiple pregnancies, with an average annual increase of 0.32% (r2 = 0.90), as well as for C-section birth (2.38% yearly increase). Of all newborn characteristics, Apgar score below 7 at 5 minutes (-0.19% per year) and low birth weight (-1.43%) decreased, whereas congenital malformations rose (0.20% per year). Efforts are required to prevent premature delivery, particularly during the moderate period, as well as greater care during the prenatal period towards expectant mothers bearing multiple pregnancies, birth defects, in addition to reducing C-section birth as it may be linked to preterm birth.

Antenatal Determinants of Bronchopulmonary Dysplasia and Late Respiratory Disease in Preterm Infants.

PubMed

Morrow, Lindsey A; Wagner, Brandie D; Ingram, David A; Poindexter, Brenda B; Schibler, Kurt; Cotten, C Michael; Dagle, John; Sontag, Marci K; Mourani, Peter M; Abman, Steven H

2017-08-01

Mechanisms contributing to chronic lung disease after preterm birth are incompletely understood. To identify antenatal risk factors associated with increased risk for bronchopulmonary dysplasia (BPD) and respiratory disease during early childhood after preterm birth, we performed a prospective, longitudinal study of 587 preterm infants with gestational age less than 34 weeks and birth weights between 500 and 1,250 g. Data collected included perinatal information and assessments during the neonatal intensive care unit admission and longitudinal follow-up by questionnaire until 2 years of age. After adjusting for covariates, we found that maternal smoking prior to preterm birth increased the odds of having an infant with BPD by twofold (P = 0.02). Maternal smoking was associated with prolonged mechanical ventilation and respiratory support during the neonatal intensive care unit admission. Preexisting hypertension was associated with a twofold (P = 0.04) increase in odds for BPD. Lower gestational age and birth weight z-scores were associated with BPD. Preterm infants who were exposed to maternal smoking had higher rates of late respiratory disease during childhood. Twenty-two percent of infants diagnosed with BPD and 34% of preterm infants without BPD had no clinical signs of late respiratory disease during early childhood. We conclude that maternal smoking and hypertension increase the odds for developing BPD after preterm birth, and that maternal smoking is strongly associated with increased odds for late respiratory morbidities during early childhood. These findings suggest that in addition to the BPD diagnosis at 36 weeks, other factors modulate late respiratory outcomes during childhood. We speculate that measures to reduce maternal smoking not only will lower the risk for preterm birth but also will improve late respiratory morbidities after preterm birth.

Particulate matter, its elemental carbon fraction, and very early preterm birth

EPA Science Inventory

Background: Particulate matter (PM) has been variably associated with preterm birth, with potentially increased vulnerability during weeks 20-27 of gestation (extremely preterm birth (EPTB)), but the role of PM components have been less studied. Objectives: To estimate associati...

Primate-specific evolution of noncoding element insertion into PLA2G4C and human preterm birth

PubMed Central

2010-01-01

Background The onset of birth in humans, like other apes, differs from non-primate mammals in its endocrine physiology. We hypothesize that higher primate-specific gene evolution may lead to these differences and target genes involved in human preterm birth, an area of global health significance. Methods We performed a comparative genomics screen of highly conserved noncoding elements and identified PLA2G4C, a phospholipase A isoform involved in prostaglandin biosynthesis as human accelerated. To examine whether this gene demonstrating primate-specific evolution was associated with birth timing, we genotyped and analyzed 8 common single nucleotide polymorphisms (SNPs) in PLA2G4C in US Hispanic (n = 73 preterm, 292 control), US White (n = 147 preterm, 157 control) and US Black (n = 79 preterm, 166 control) mothers. Results Detailed structural and phylogenic analysis of PLA2G4C suggested a short genomic element within the gene duplicated from a paralogous highly conserved element on chromosome 1 specifically in primates. SNPs rs8110925 and rs2307276 in US Hispanics and rs11564620 in US Whites were significant after correcting for multiple tests (p < 0.006). Additionally, rs11564620 (Thr360Pro) was associated with increased metabolite levels of the prostaglandin thromboxane in healthy individuals (p = 0.02), suggesting this variant may affect PLA2G4C activity. Conclusions Our findings suggest that variation in PLA2G4C may influence preterm birth risk by increasing levels of prostaglandins, which are known to regulate labor. PMID:21184677

Examination of the association between male gender and preterm delivery.

PubMed

Brettell, Rachel; Yeh, Peter S; Impey, Lawrence W M

2008-12-01

To examine possible reasons why a male fetus constitutes a risk factor for preterm delivery. Retrospective study of deliveries from hospital database in a UK teaching hospital. The population comprised all deliveries >23 weeks over an 11-year period, excluding multiples, terminations and pregnancies with major abnormalities including indeterminate gender. Obstetric variables and outcomes were initially compared in male and female babies for preterm births in different gestation bands, extreme (<28 weeks), severe (29-32 weeks) and moderate (33-36 weeks). For each, the odds ratios with 95% confidence intervals for preterm delivery were calculated. Then, using binary logistic regression with adjusted odds ratios with 95% confidence intervals, putative causal pathways that might explain the male excess were tested. 75,725 deliveries occurred, of which 4003 (5.3%) were preterm. Males delivered preterm more frequently (OR 1.13, 95% CI 1.06-1.20). This was due to spontaneous (OR 1.30, 95% CI 1.19-1.42) but not iatrogenic (OR 0.96, 95% CI 0.87-1.05) preterm birth. There was an increased risk of pre eclampsia among preterm females. Although males were larger, and male pregnancies were more frequently nulliparous and affected by some other obstetric complications (abruption, urinary tract infection), these did not account for their increased risk. Any effect of growth restriction could not be properly determined. Being male carries an increased risk of spontaneous but not iatrogenic preterm birth. The reasons behind this remain obscure.

Family functioning, burden and parenting stress 2 years after very preterm birth.

PubMed

Treyvaud, Karli; Doyle, Lex W; Lee, Katherine J; Roberts, Gehan; Cheong, Jeanie L Y; Inder, Terrie E; Anderson, Peter J

2011-06-01

Examining rates of difficulties in family functioning following very preterm birth has been a relatively neglected area of research. To examine family functioning, burden and parenting stress in families with very preterm compared with term born children, and investigate influences of parental mental health problems and child neurodevelopmental disability on family outcomes in families with preterm children. Participants were 184 very preterm and 71 term children and their parents. Parents completed the Family Assessment Device, Parenting Stress Index and Impact on Family questionnaires when their children were 2 years old (corrected for prematurity). Parental mental health and social risk information were also collected. Children were assessed for neurodevelopmental disability. Families with very preterm children reported poorer family functioning (p=.03) compared with families with term born children, with less evidence for differences between families with very preterm and term born children in parenting stress and family burden. Within very preterm families, parental mental health problems were associated with higher levels of parenting stress (p=.001), and parents of children with a neurodevelopmental disability were more likely to report higher family burden (p=.04). For families with very preterm children, parental mental health symptoms and child neurodevelopmental disability may identify families at risk of greater stress and burden who may benefit from additional support. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

High environmental temperature and preterm birth: a review of the evidence.

PubMed

Carolan-Olah, Mary; Frankowska, Dorota

2014-01-01

to examine the evidence in relation to preterm birth and high environmental temperature. this review was conducted against a background of global warming and an escalation in the frequency and severity of hot weather together with a rising preterm birth rate. electronic health databases such as: SCOPUS, MEDLINE, CINAHL, EMBASE and Maternity and Infant Care were searched for research articles, that examined preterm birth and high environmental temperature. Further searches were based on the reference lists of located articles. Keywords included a search term for preterm birth (preterm birth, preterm, premature, <37 weeks, gestation) and a search term for hot weather (heatwaves, heat-waves, global warming, climate change, extreme heat, hot weather, high temperature, ambient temperature). A total of 159 papers were retrieved in this way. Of these publications, eight met inclusion criteria. data were extracted and organised under the following headings: study design; dataset and sample; gestational age and effect of environmental heat on preterm birth. Critical Appraisal Skills Programme (CASP) guidelines were used to appraise study quality. in this review, the weight of evidence supported an association between high environmental temperature and preterm birth. However, the degree of association varied considerably, and it is not clear what factors influence this relationship. Differing definitions of preterm birth may also add to lack of clarity. preterm birth is an increasingly common and debilitating condition that affects a substantial portion of infants. Rates appear to be linked to high environmental temperature, and more especially heat stress, which may be experienced during extreme heat or following a sudden rise in temperature. When this happens, the body may be unable to adapt quickly to the change. As global warming continues, the incidence of high environmental temperature and dramatic temperature changes are also increasing. This situation makes it important that research effort is directed to understanding the degree of association and the mechanism by which high temperature and temperature increases impact on preterm birth. Research is also warranted into the development of more effective cooling practices to ameliorate the effects of heat stress. In the meantime, it is important that pregnant women are advised to take special precautions to avoid heat stress and to keep cool when there are sudden increases in temperature. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preterm or not--an evaluation of estimates of gestational age in a cohort of women from Rural Papua New Guinea.

PubMed

Karl, Stephan; Li Wai Suen, Connie S N; Unger, Holger W; Ome-Kaius, Maria; Mola, Glen; White, Lisa; Wangnapi, Regina A; Rogerson, Stephen J; Mueller, Ivo

2015-01-01

Knowledge of accurate gestational age is required for comprehensive pregnancy care and is an essential component of research evaluating causes of preterm birth. In industrialised countries gestational age is determined with the help of fetal biometry in early pregnancy. Lack of ultrasound and late presentation to antenatal clinic limits this practice in low-resource settings. Instead, clinical estimators of gestational age are used, but their accuracy remains a matter of debate. In a cohort of 688 singleton pregnancies from rural Papua New Guinea, delivery gestational age was calculated from Ballard score, last menstrual period, symphysis-pubis fundal height at first visit and quickening as well as mid- and late pregnancy fetal biometry. Published models using sequential fundal height measurements and corrected last menstrual period to estimate gestational age were also tested. Novel linear models that combined clinical measurements for gestational age estimation were developed. Predictions were compared with the reference early pregnancy ultrasound (<25 gestational weeks) using correlation, regression and Bland-Altman analyses and ranked for their capability to predict preterm birth using the harmonic mean of recall and precision (F-measure). Average bias between reference ultrasound and clinical methods ranged from 0-11 days (95% confidence levels: 14-42 days). Preterm birth was best predicted by mid-pregnancy ultrasound (F-measure: 0.72), and neuromuscular Ballard score provided the least reliable preterm birth prediction (F-measure: 0.17). The best clinical methods to predict gestational age and preterm birth were last menstrual period and fundal height (F-measures 0.35). A linear model combining both measures improved prediction of preterm birth (F-measure: 0.58). Estimation of gestational age without ultrasound is prone to significant error. In the absence of ultrasound facilities, last menstrual period and fundal height are among the more reliable clinical measures. This study underlines the importance of strengthening ultrasound facilities and developing novel ways to estimate gestational age.

Mother's education and the risk of preterm and small for gestational age birth: a DRIVERS meta-analysis of 12 European cohorts.

PubMed

Ruiz, Milagros; Goldblatt, Peter; Morrison, Joana; Kukla, Lubomír; Švancara, Jan; Riitta-Järvelin, Marjo; Taanila, Anja; Saurel-Cubizolles, Marie-Josèphe; Lioret, Sandrine; Bakoula, Chryssa; Veltsista, Alexandra; Porta, Daniela; Forastiere, Francesco; van Eijsden, Manon; Vrijkotte, Tanja G M; Eggesbø, Merete; White, Richard A; Barros, Henrique; Correia, Sofia; Vrijheid, Martine; Torrent, Maties; Rebagliato, Marisa; Larrañaga, Isabel; Ludvigsson, Johnny; Olsen Faresjö, Åshild; Hryhorczuk, Daniel; Antipkin, Youriy; Marmot, Michael; Pikhart, Hynek

2015-09-01

A healthy start to life is a major priority in efforts to reduce health inequalities across Europe, with important implications for the health of future generations. There is limited combined evidence on inequalities in health among newborns across a range of European countries. Prospective cohort data of 75 296 newborns from 12 European countries were used. Maternal education, preterm and small for gestational age births were determined at baseline along with covariate data. Regression models were estimated within each cohort and meta-analyses were conducted to compare and measure heterogeneity between cohorts. Mother's education was linked to an appreciable risk of preterm and small for gestational age (SGA) births across 12 European countries. The excess risk of preterm births associated with low maternal education was 1.48 (1.29 to 1.69) and 1.84 (0.99 to 2.69) in relative and absolute terms (Relative/Slope Index of Inequality, RII/SII) for all cohorts combined. Similar effects were found for SGA births, but absolute inequalities were greater, with an SII score of 3.64 (1.74 to 5.54). Inequalities at birth were strong in the Netherlands, the UK, Sweden and Spain and marginal in other countries studied. This study highlights the value of comparative cohort analysis to better understand the relationship between maternal education and markers of fetal growth in different settings across Europe. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Altered gene expression in human placenta after suspected preterm labour.

PubMed

Oros, D; Strunk, M; Breton, P; Paules, C; Benito, R; Moreno, E; Garcés, M; Godino, J; Schoorlemmer, J

2017-07-01

Suspected preterm labour occurs in around 9% of pregnancies. However, almost two-thirds of women admitted for threatened preterm labour ultimately deliver at term and are considered risk-free for fetal development. We examined placental and umbilical cord blood samples from preterm or term deliveries after threatened preterm labour as well as term deliveries without threatened preterm labour. We quantitatively analysed the mRNA expression of inflammatory markers (IL6, IFNγ, and TNFα) and modulators of angiogenesis (FGF2, PGF, VEGFA, VEGFB, and VEGFR1). A total of 132 deliveries were analysed. Preterm delivery and term delivery after suspected preterm labour groups showed similar increases in TNFα expression compared with the term delivery control group in umbilical cord blood samples. Placental samples from preterm and term deliveries after suspected preterm labour exhibited significantly increased expression of TNFα and IL6 and decreased expression of IFNγ. Suspected preterm labour was also associated with altered expression of angiogenic factors, although not all differences reached statistical significance. We found gene expression patterns indicative of inflammation in human placentas after suspected preterm labour regardless of whether the deliveries occurred preterm or at term. Similarly, a trend towards altered expression of angiogeneic factors was not limited to preterm birth. These findings suggest that the biological mechanisms underlying threatened preterm labour affect pregnancies independently of gestational age at birth. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationship between 17-alpha hydroxyprogesterone caproate concentration and spontaneous preterm birth.

PubMed

Caritis, Steve N; Venkataramanan, Raman; Thom, Elizabeth; Harper, Margaret; Klebanoff, Mark A; Sorokin, Yoram; Thorp, John M; Varner, Michael W; Wapner, Ronald J; Iams, Jay D; Carpenter, Marshall W; Grobman, William A; Mercer, Brian M; Sciscione, Anthony; Rouse, Dwight J; Ramin, Susan

2014-02-01

17-alpha hydroxyprogesterone caproate 250 mg weekly reduces recurrent spontaneous preterm birth in women with a prior spontaneous preterm birth by 33%. The dose is not based on pharmacologic considerations. A therapeutic concentration has not been determined hampering any attempt to optimize treatment. This study evaluated the relationship between 17-alpha hydroxyprogesterone caproate plasma concentrations and the rate of spontaneous preterm birth in women with singleton gestation. A single blood sample was obtained between 25 and 28 weeks' gestation from 315 women with a spontaneous preterm birth who participated in a placebo-controlled, prospective, randomized clinical trial evaluating the benefit of omega-3 supplementation in reducing preterm birth. All women in the parent study received 17-alpha hydroxyprogesterone caproate and 434 received omega-3 supplementation and 418 received a placebo. Plasma from 315 consenting women was analyzed for 17-alpha hydroxyprogesterone caproate concentration. There were no differences between placebo and omega-3 supplemented groups in demographic variables, outcomes or in mean 17-alpha hydroxyprogesterone caproate concentration. Plasma concentrations of 17-alpha hydroxyprogesterone caproate ranged from 3.7-56 ng/mL. Women with plasma concentrations of 17-alpha hydroxyprogesterone caproate in the lowest quartile had a significantly higher risk of spontaneous preterm birth (P = .03) and delivered at significantly earlier gestational ages (P = .002) than did women in the second to fourth quartiles. The lowest preterm birth rates were seen when median 17-alpha hydroxyprogesterone caproate concentrations exceeded 6.4 ng/mL. Low plasma 17-alpha hydroxyprogesterone caproate concentration is associated with an increased risk of spontaneous preterm birth. This finding validates efficacy of this treatment but suggests that additional studies are needed to determine the optimal dosage. Copyright © 2014 Mosby, Inc. All rights reserved.

Development of a prognostic model for predicting spontaneous singleton preterm birth.

PubMed

Schaaf, Jelle M; Ravelli, Anita C J; Mol, Ben Willem J; Abu-Hanna, Ameen

2012-10-01

To develop and validate a prognostic model for prediction of spontaneous preterm birth. Prospective cohort study using data of the nationwide perinatal registry in The Netherlands. We studied 1,524,058 singleton pregnancies between 1999 and 2007. We developed a multiple logistic regression model to estimate the risk of spontaneous preterm birth based on maternal and pregnancy characteristics. We used bootstrapping techniques to internally validate our model. Discrimination (AUC), accuracy (Brier score) and calibration (calibration graphs and Hosmer-Lemeshow C-statistic) were used to assess the model's predictive performance. Our primary outcome measure was spontaneous preterm birth at <37 completed weeks. Spontaneous preterm birth occurred in 57,796 (3.8%) pregnancies. The final model included 13 variables for predicting preterm birth. The predicted probabilities ranged from 0.01 to 0.71 (IQR 0.02-0.04). The model had an area under the receiver operator characteristic curve (AUC) of 0.63 (95% CI 0.63-0.63), the Brier score was 0.04 (95% CI 0.04-0.04) and the Hosmer Lemeshow C-statistic was significant (p<0.0001). The calibration graph showed overprediction at higher values of predicted probability. The positive predictive value was 26% (95% CI 20-33%) for the 0.4 probability cut-off point. The model's discrimination was fair and it had modest calibration. Previous preterm birth, drug abuse and vaginal bleeding in the first half of pregnancy were the most important predictors for spontaneous preterm birth. Although not applicable in clinical practice yet, this model is a next step towards early prediction of spontaneous preterm birth that enables caregivers to start preventive therapy in women at higher risk. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Cell-free fetal DNA and spontaneous preterm birth

PubMed Central

Davidson, Donald J; Norman, Jane E

2018-01-01

Inflammation is known to play a key role in preterm and term parturition. Cell-free fetal DNA (cff-DNA) is present in the maternal circulation and increases with gestational age and some pregnancy complications (e.g. preterm birth, preeclampsia). Microbial DNA and adult cell-free DNA can be pro-inflammatory through DNA-sensing mechanisms such as Toll-like receptor 9 and the Stimulator of Interferon Genes (STING) pathway. However, the pro-inflammatory properties of cff-DNA, and the possible effects of this on pregnancy and parturition are unknown. Clinical studies have quantified cff-DNA levels in the maternal circulation in women who deliver preterm and women who deliver at term and show an association between preterm labor and higher cff-DNA levels in the 2nd, 3rd trimester and at onset of preterm birth symptoms. Together with potential pro-inflammatory properties of cff-DNA, this rise suggests a potential mechanistic role in the pathogenesis of spontaneous preterm birth. In this review, we discuss the evidence linking cff-DNA to adverse pregnancy outcomes, including preterm birth, obtained from preclinical and clinical studies. PMID:29269517

The use of psychosocial stress scales in preterm birth research

PubMed Central

CHEN, Melissa J.; GROBMAN, William A.; GOLLAN, Jackie K.; BORDERS, Ann E.B.

2011-01-01

Psychosocial stress has been identified as a potential risk factor for preterm birth. However, an association has not consistently been found, and a consensus on the extent to which stress and preterm birth are linked is still lacking. A literature search was performed with a combination of keywords and MeSH terms to detect studies of psychosocial stress and preterm birth. Studies were included in the review if psychosocial stress was measured with a standardized, validated instrument and the outcomes included either preterm birth or low birth weight. Within the 138 studies that met inclusion criteria, 85 different instruments were used. Measures designed specifically for pregnancy were used infrequently, although scales were sometimes modified for the pregnant population. The many different measures used may be one factor that accounts for the inconsistent associations that have been observed. PMID:21816383

Neonatal mortality risks among preterm births in a rural Bangladeshi cohort.

PubMed

Shah, Rashed; Mullany, Luke C; Darmstadt, Gary L; Talukder, Radwanur Rahman; Rahman, Syed Moshfiqur; Mannan, Ishtiaq; Arifeen, Shams El; Baqui, Abdullah H

2014-11-01

Preterm birth leads to an estimated 35% of neonatal deaths worldwide. Our study analyses neonatal mortality risks among preterm births in rural Bangladesh. Trained community health workers (CHW) prospectively collected data between June 2007 and September 2009. Among 32 126 livebirths, 22.3% were preterm (delivered at <37 weeks gestation) and almost half (46.4%) of all neonatal deaths occurred among preterm babies. Preterm babies who were born as the first child {[risk ratio (RR) 1.4; 95% confidence interval (CI) 1.1, 1.8]} and in the poorest households [RR 1.7; 95% CI 1.2, 2.4] were at higher mortality risk. Birth and newborn care preparedness was associated with lower risk of mortality [RR 0.3; 95% CI 0.2, 0.4] while preterm infants who had symptoms of infection [RR 5.6; 95% CI 4.3, 7.1] or whose mother suffered antenatal complications [RR 1.4; 95% CI 1.1, 1.8] were at higher mortality risk. Elimination of excess neonatal deaths caused by preterm would decrease population-level neonatal mortality rate by 31.0% [95% CI 27.60%, 34.5%]. Given that 87% of preterm births and 60% of preterm deaths were in late or moderate preterm infants, and that 87% preterm babies received a visit from CHW within third day of life, a home-based essential care package delivered by CHWs for sick preterm infants, specifically focused on birth preparedness, skin-to-skin care, immediate breast feeding, early recognition of danger signs, and linked through referral to intensive and quality care in health facilities, could be an effective approach in low resource settings. © 2014 John Wiley & Sons Ltd.

Using Geographic Information Science to Explore Associations between Air Pollution, Environmental Amenities, and Preterm Births

PubMed Central

Ogneva-Himmelberger, Yelena; Dahlberg, Tyler; Kelly, Kristen; Simas, Tiffany A. Moore

2015-01-01

The study uses geographic information science (GIS) and statistics to find out if there are statistical differences between full term and preterm births to non-Hispanic white, non-Hispanic Black, and Hispanic mothers in their exposure to air pollution and access to environmental amenities (green space and vendors of healthy food) in the second largest city in New England, Worcester, Massachusetts. Proximity to a Toxic Release Inventory site has a statistically significant effect on preterm birth regardless of race. The air-pollution hazard score from the Risk Screening Environmental Indicators Model is also a statistically significant factor when preterm births are categorized into three groups based on the degree of prematurity. Proximity to green space and to a healthy food vendor did not have an effect on preterm births. The study also used cluster analysis and found statistically significant spatial clusters of high preterm birth volume for non-Hispanic white, non-Hispanic Black, and Hispanic mothers. PMID:29546120

Using Geographic Information Science to Explore Associations between Air Pollution, Environmental Amenities, and Preterm Births.

PubMed

Ogneva-Himmelberger, Yelena; Dahlberg, Tyler; Kelly, Kristen; Simas, Tiffany A Moore

2015-01-01

The study uses geographic information science (GIS) and statistics to find out if there are statistical differences between full term and preterm births to non-Hispanic white, non-Hispanic Black, and Hispanic mothers in their exposure to air pollution and access to environmental amenities (green space and vendors of healthy food) in the second largest city in New England, Worcester, Massachusetts. Proximity to a Toxic Release Inventory site has a statistically significant effect on preterm birth regardless of race. The air-pollution hazard score from the Risk Screening Environmental Indicators Model is also a statistically significant factor when preterm births are categorized into three groups based on the degree of prematurity. Proximity to green space and to a healthy food vendor did not have an effect on preterm births. The study also used cluster analysis and found statistically significant spatial clusters of high preterm birth volume for non-Hispanic white, non-Hispanic Black, and Hispanic mothers.

The effect of cotrimoxazole prophylactic treatment on malaria, birth outcomes, and postpartum CD4 count in HIV-infected women.

PubMed

Dow, Anna; Kayira, Dumbani; Hudgens, Michael G; Van Rie, Annelies; King, Caroline C; Ellington, Sascha; Chome, Nelecy; Kourtis, Athena; Turner, Abigail Norris; Kacheche, Zebrone; Jamieson, Denise J; Chasela, Charles; van der Horst, Charles

2013-01-01

Limited data exist on cotrimoxazole prophylactic treatment (CPT) in pregnant women, including protection against malaria versus standard intermittent preventive therapy with sulfadoxine-pyrimethamine (IPTp). Using observational data we examined the effect of CPT in HIV-infected pregnant women on malaria during pregnancy, low birth weight and preterm birth using proportional hazards, logistic, and log binomial regression, respectively. We used linear regression to assess effect of CPT on CD4 count. Data from 468 CPT-exposed and 768 CPT-unexposed women were analyzed. CPT was associated with protection against malaria versus IPTp (hazard ratio: 0.35, 95% Confidence Interval (CI): 0.20, 0.60). After adjustment for time period this effect was not statistically significant (adjusted hazard ratio: 0.66, 95% CI: 0.28, 1.52). Among women receiving and not receiving CPT, rates of low birth weight (7.1% versus 7.6%) and preterm birth (23.5% versus 23.6%) were similar. CPT was associated with lower CD4 counts 24 weeks postpartum in women receiving (-77.6 cells/ μ L, 95% CI: -125.2, -30.1) and not receiving antiretrovirals (-33.7 cells/ μ L, 95% CI: -58.6, -8.8). Compared to IPTp, CPT provided comparable protection against malaria in HIV-infected pregnant women and against preterm birth or low birth weight. Possible implications of CPT-associated lower CD4 postpartum warrant further examination.

Exposure to firework chemicals from production factories in pregnant women and risk of preterm birth occurrence in Liuyang, China.

PubMed

Li, Xun; Tan, Hongzhuan; Luo, Meiling; Wu, Xinrui; Huang, Xin; Zhou, Shujin; Shen, Lin; He, Yue; Liu, Yi; Hu, Li; Chen, Mengshi; Hu, Shimin; Wen, Shi Wu

2018-01-01

In the production of fireworks, various pollutants including particles of metals and organic compounds are released into the environment. Although the adverse effects of these air pollutants are known, the impact on pregnant women residing in this area remains to be determined. The aim of this study was to examine the association between maternal exposure to fireworks production chemicals and frequency of preterm birth in Liuyang, China. Maternal exposure to fireworks production was estimated at the residential district level and assessed using factory density, which was defined as the number of fireworks factories per 1000 residents in each district. The association of maternal exposure to particulates released from fireworks production plants with frequency of preterm birth was determined using data obtained from a cohort study conducted in Liuyang, China. Data were analyzed utilizing linear regression and logistic regression. There was no significant association between factory density and spontaneous preterm or medically induced preterm birth. Unexpectedly, pregnant women residing in areas with higher density of fireworks factories were at a reduced risk of preterm premature rupture of membranes (PPROM). Data demonstrated that residential density of fireworks factories appeared to be negatively correlated with preterm birth rate as evidenced by PPROM. At present, it is difficult to reconcile the inverse relationship between firework chemical exposure and frequency of preterm births as ambient particulate inhalation is known to adversely affect preterm birth occurrence.

Rate of preterm births in pregnant women with common lower genital tract infection: a population-based study based on the clinical practice.

PubMed

Bánhidy, Ferenc; Acs, Nándor; Puho, Erzsébet H; Czeizel, Andrew E

2009-05-01

To estimate the rate of preterm births in pregnant women with lower genital tract infection, i.e. vulvovaginitis-bacterial vaginosis and to check their prevention by drug treatments in the usual clinical practice. The rate of preterm birth of pregnant women with or without lower genital tract infection was evaluated in the population-based large data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities. Only prospectively and medically recorded diagnoses of vulvovaginitis-bacterial vaginosis were evaluated. Of 38,151 newborn infants, 2698 (7.1%) had mothers with vulvovaginitis-bacterial vaginosis diagnosed in early pregnancy and the rate of preterm births was 7.5% among them, while this figure was 9.3% in babies born to mothers without these recognized genital infections. After early diagnosis and treatment of vulvovaginitis-bacterial vaginosis, clotrimazole and ampicillin seemed to be most effective to reduce the preterm birth during the study period. However, the rate of preterm births was lower in babies born to mothers without recorded vulvovaginitis-bacterial vaginosis but treated by clotrimazole and ampicillin (7.2-7.8%) as well. The lower rate of preterm births in babies born to mothers with vulvovaginitis-bacterial vaginosis may be explained by their effective treatment. However, the high rate of preterm births in pregnant women without genital tract infection and antimicrobial treatment may be connected with asymptomatic or unrecognized symptomatic and untreated vaginal infections.

Banked preterm versus banked term human milk to promote growth and development in very low birth weight infants.

PubMed

Dempsey, Eugene; Miletin, Jan

2010-06-16

Human milk banking has been available in many countries for the last three decades. The milk provided from milk banking is predominantly term breast milk, but some milk banks provide preterm breast milk. There are a number of differences between donor term and donor preterm human milk. To determine the effect of banked preterm milk compared with banked term milk regarding growth and developmental outcome in very low birth weight infants (infants weighing less than 1500 g). We used the standard methods of the Cochrane Neonatal Review Group, including a search of the Cochrane Neonatal Group specialized register and the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, January 2010). We searched the computerised bibliographic databases MEDLINE (1966 to February 2010), EMBASE (1988 to February 2010) and Web of Science (1975 to February 2010). We searched reference lists of all selected articles, review articles and the Oxford Database of Perinatal Trials. We also searched abstracts from neonatal and pediatric meetings (PAS electronic version from 2000 to 2009, ESPR hand search from 2000 to 2009). We applied no language restrictions. Randomised and quasi-randomised trials comparing banked donor preterm milk with banked donor term milk regarding growth and developmental outcomes in very low birth weight infants We planned to perform assessment of methodology regarding blinding of randomisation, intervention and outcome measurements as well as completeness of follow-up. We planned to evaluate treatment effect using a fixed-effect model using relative risk (RR), relative risk reduction, risk difference (RD) and number needed to treat (NNT) for categorical data and using mean, standard deviation and weighted mean difference (WMD) for continuous data. We planned an evaluation of heterogeneity. No studies met the inclusion criteria. There are no randomised trials that compare preterm banked milk to banked term milk to promote growth and development in very low birth weight infants.

Neurobehaviour between birth and 40 weeks' gestation in infants born <30 weeks' gestation and parental psychological wellbeing: predictors of brain development and child outcomes.

PubMed

Spittle, Alicia J; Thompson, Deanne K; Brown, Nisha C; Treyvaud, Karli; Cheong, Jeanie L Y; Lee, Katherine J; Pace, Carmen C; Olsen, Joy; Allinson, Leesa G; Morgan, Angela T; Seal, Marc; Eeles, Abbey; Judd, Fiona; Doyle, Lex W; Anderson, Peter J

2014-04-24

Infants born <30 weeks' gestation are at increased risk of long term neurodevelopmental problems compared with term born peers. The predictive value of neurobehavioural examinations at term equivalent age in very preterm infants has been reported for subsequent impairment. Yet there is little knowledge surrounding earlier neurobehavioural development in preterm infants prior to term equivalent age, and how it relates to perinatal factors, cerebral structure, and later developmental outcomes. In addition, maternal psychological wellbeing has been associated with child development. Given the high rate of psychological distress reported by parents of preterm children, it is vital we understand maternal and paternal wellbeing in the early weeks and months after preterm birth and how this influences the parent-child relationship and children's outcomes. Therefore this study aims to examine how 1) early neurobehaviour and 2) parental mental health relate to developmental outcomes for infants born preterm compared with infants born at term. This prospective cohort study will describe the neurobehaviour of 150 infants born at <30 weeks' gestational age from birth to term equivalent age, and explore how early neurobehavioural deficits relate to brain growth or injury determined by magnetic resonance imaging, perinatal factors, parental mental health and later developmental outcomes measured using standardised assessment tools at term, one and two years' corrected age. A control group of 150 healthy term-born infants will also be recruited for comparison of outcomes. To examine the effects of parental mental health on developmental outcomes, both parents of preterm and term-born infants will complete standardised questionnaires related to symptoms of anxiety, depression and post-traumatic stress at regular intervals from the first week of their child's birth until their child's second birthday. The parent-child relationship will be assessed at one and two years' corrected age. Detailing the trajectory of infant neurobehaviour and parental psychological distress following very preterm birth is important not only to identify infants most at risk, further understand the parental experience and highlight potential times for intervention for the infant and/or parent, but also to gain insight into the effect this has on parent-child interaction and child development.

Re-evaluation of link between interpregnancy interval and adverse birth outcomes: retrospective cohort study matching two intervals per mother

PubMed Central

Pereira, Gavin; Jacoby, Peter; de Klerk, Nicholas; Stanley, Fiona J

2014-01-01

Objective To re-evaluate the causal effect of interpregnancy interval on adverse birth outcomes, on the basis that previous studies relying on between mother comparisons may have inadequately adjusted for confounding by maternal risk factors. Design Retrospective cohort study using conditional logistic regression (matching two intervals per mother so each mother acts as her own control) to model the incidence of adverse birth outcomes as a function of interpregnancy interval; additional unconditional logistic regression with adjustment for confounders enabled comparison with the unmatched design of previous studies. Setting Perth, Western Australia, 1980-2010. Participants 40 441 mothers who each delivered three liveborn singleton neonates. Main outcome measures Preterm birth (<37 weeks), small for gestational age birth (<10th centile of birth weight by sex and gestational age), and low birth weight (<2500 g). Results Within mother analysis of interpregnancy intervals indicated a much weaker effect of short intervals on the odds of preterm birth and low birth weight compared with estimates generated using a traditional between mother analysis. The traditional unmatched design estimated an adjusted odds ratio for an interpregnancy interval of 0-5 months (relative to the reference category of 18-23 months) of 1.41 (95% confidence interval 1.31 to 1.51) for preterm birth, 1.26 (1.15 to 1.37) for low birth weight, and 0.98 (0.92 to 1.06) for small for gestational age birth. In comparison, the matched design showed a much weaker effect of short interpregnancy interval on preterm birth (odds ratio 1.07, 0.86 to 1.34) and low birth weight (1.03, 0.79 to 1.34), and the effect for small for gestational age birth remained small (1.08, 0.87 to 1.34). Both the unmatched and matched models estimated a high odds of small for gestational age birth and low birth weight for long interpregnancy intervals (longer than 59 months), but the estimated effect of long interpregnancy intervals on the odds of preterm birth was much weaker in the matched model than in the unmatched model. Conclusion This study questions the causal effect of short interpregnancy intervals on adverse birth outcomes and points to the possibility of unmeasured or inadequately specified maternal factors in previous studies. PMID:25056260

Race differences in infant mortality from endogenous causes: a population-based study in North Carolina.

PubMed

Michielutte, R; Moore, M L; Meis, P J; Ernest, J M; Wells, H B

1994-02-01

This study examines the associations between race, birth weight, and mortality from endogenous causes for all singleton births born in 1984-1987 in a 20-county region of North Carolina. A more detailed analysis of preterm low birth weight infants examines these associations according to the proximate medical causes (medical etiology) of the preterm birth. Overall, black infants were found to have approximately twice the mortality risk of white infants. Most of the excess black mortality risk is explained by the larger proportion of black infants born at lower birth weights. The pattern of race differences in infant mortality by birth weight generally replicates the results of earlier studies, but the relative risk ratios within specific birth weight categories are smaller than previously reported. Among preterm low birth weight infants, the association between race and endogenous mortality differs within categories of medical etiology. The mortality risk is the same for black and white infants born preterm due to premature rupture of the membranes (PROM), lower for black infants born preterm due to medical problems, and higher for black infants born preterm due to idiopathic premature labor (IPL).

Variability in urinary phthalate metabolite levels across pregnancy and sensitive windows of exposure for the risk of preterm birth

PubMed Central

Ferguson, Kelly K.; McElrath, Thomas F.; Ko, Yi-An; Mukherjee, Bhramar; Meeker, John D.

2014-01-01

Background Preterm birth is a significant public health problem, affecting over 1 in 10 live births and contributing largely to infant mortality and morbidity. Everyday exposure to environmental chemicals such as phthalates could contribute, and may be modifiable. In the present study we examine variability in phthalate exposure across gestation and identify windows of susceptibility for the relationship with preterm birth. Methods Women were recruited early in pregnancy as part of a prospective, longitudinal birth cohort at the Brigham and Women’s Hospital in Boston, Massachusetts. Urine samples were collected at up to 4 time points during gestation for phthalate measurement, and birth outcomes were recorded at delivery. From this population we selected all 130 cases of preterm birth, defined as delivery before 37 weeks completed gestation, as well as 352 random controls. Results Urinary phthalate metabolite levels were moderately variable over pregnancy, but levels measured at multiple time points were associated with increased odds of preterm birth. Adjusted odds ratios (aOR) for spontaneous preterm birth were strongest in association with phthalate metabolite concentrations measured at the beginning of the third trimester (aOR for summed di-2-ethylhexyl phthalate metabolites [∑DEHP]=1.33, 95% confidence interval [CI]=1.02, 1.73). Odds ratios for placental preterm birth, defined as delivery with presentation of preeclampsia or intrauterine growth restriction, were slightly elevated in the first trimester for DEHP metabolites (aOR for ∑DEHP=1.33, 95% CI=0.99, 1.78). Conclusions Pregnant women with exposure to phthalates both early and late in pregnancy are at increased risk of delivering preterm, but mechanisms may differ based on etiology. PMID:24934852

Bed rest in singleton pregnancies for preventing preterm birth.

PubMed

Sosa, C; Althabe, F; Belizán, J; Bergel, E

2004-01-01

Bed rest in hospital or at home is widely recommended for the prevention of preterm birth. This advice is based on the observation that hard work and hard physical activity during pregnancy could be associated with preterm birth and with the idea that bed rest could reduce uterine activity. However, bed rest may have some adverse effects on other outcomes. To evaluate the effect of prescription of bed rest in hospital or at home for preventing preterm birth in pregnant women at high risk of preterm birth. We searched the Cochrane Pregnancy and Childbirth Group trials register (July 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2003), MEDLINE (July 2003), LILACS (July 2003), EMBASE (July 2003), POPLINE (July 2003) and bibliographies of relevant papers. Randomized and quasi-randomized controlled trials with reported data that assess clinical outcomes in women at high risk of spontaneous preterm birth who were prescribed bed rest in hospital or at home for preventing preterm birth, and their babies. Two reviewers independently assessed eligibility, trial quality and extracted data. One study met the inclusion criteria (1266 women). This trial has uncertain methodological quality due to lack of reporting. Four hundred and thirty-two women were prescribed bed rest at home and a total of 834 women received a placebo (412) or no intervention (422). Preterm birth before 37 weeks was similar in both groups (7.9% in the intervention group versus 8.5% in the control group), and the relative risk was 0.92 with a 95% confidence interval from 0.62 to 1.37. No other results were available. There is no evidence, either supporting or refuting the use of bed rest at home or in hospital, to prevent preterm birth. Although bed rest in hospital or at home is widely used as the first step of treatment, there is no evidence that this practice could be beneficial. Due to the potential adverse effects that bed rest could have on women and their families, and the increased costs for the healthcare system, clinicians should not routinely advise women to rest in bed to prevent preterm birth. Potential benefits and harms should be discussed with women facing an increased risk of preterm birth. Appropriate research is mandatory. Future trials should evaluate both the effectiveness of bed rest, and the effectiveness of the prescription of bed rest, to prevent preterm birth.

Estimated number of preterm births and low birth weight children born in the United States due to maternal binge drinking.

PubMed

Truong, Khoa D; Reifsnider, Odette S; Mayorga, Maria E; Spitler, Hugh

2013-05-01

The objective of this study was to estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. To estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. A simulation model was developed to estimate the number of PTB and LBW cases due to maternal binge drinking. Data inputs for the model included number of births and rates of preterm and LBW from the National Center for Health Statistics; female population by childbearing age groups from the U.S. Census; increased relative risks of preterm and LBW deliveries due to maternal binge drinking extracted from the literature; and adjusted prevalence of binge drinking among pregnant women estimated in a multivariate logistic regression model using Behavioral Risk Factor Surveillance System survey. The most conservative estimates attributed maternal binge drinking to 8,701 (95% CI: 7,804-9,598) PTBs (1.75% of all PTBs) and 5,627 (95% CI 5,121-6,133) LBW deliveries in 2008, with 3,708 (95% CI: 3,375-4,041) cases of both PTB and LBW. The estimated rate of PTB due to maternal binge drinking was 1.57% among all PTBs to White women, 0.69% among Black women, 3.31% among Hispanic women, and 2.35% among other races. Compared to other age groups, women ages 40-44 had the highest adjusted binge drinking rate and highest PTB rate due to maternal binge drinking (4.33%). Maternal binge drinking contributed significantly to PTB and LBW differentially across sociodemographic groups.

Maternal social support and neighborhood income inequality as predictors of low birth weight and preterm birth outcome disparities: analysis of South Carolina Pregnancy Risk Assessment and Monitoring System survey, 2000-2003.

PubMed

Nkansah-Amankra, Stephen; Dhawain, Ashish; Hussey, James Robert; Luchok, Kathryn J

2010-09-01

Effects of income inequality on health and other social systems have been a subject of considerable debate, but only a few studies have used multilevel models to evaluate these relationships. The main objectives of the study were to (1) Evaluate the relationships among neighborhood income inequality, social support and birth outcomes (low birth weight, and preterm delivery) and (2) Assess variations in racial disparities in birth outcomes across neighborhood contexts of income distribution and maternal social support. We evaluated these relationships by using South Carolina Pregnancy Risk Assessment and Monitoring System (PRAMS) survey for 2000-2003 geocoded to 2000 US Census data for South Carolina. Multilevel analysis was used to simultaneously evaluate the association between income inequality (measured as Gini), maternal social relationships and birth outcomes (low birth weight and preterm delivery). The results showed residence in neighborhoods with medium levels of income inequality was independently associated with low birth weight (OR: 2.00; 95% CI 1.14-3.26), but not preterm birth; low social support was an independent risk for low birth weight or preterm births. The evidence suggests that non-Hispanic black mothers were at increased risks of low birth weight or preterm birth primarily due to greater exposures of neighborhood deprivations associated with low income and reduced social support and modified by unequal income distribution.

Revisiting the Table 2 fallacy: A motivating example examining preeclampsia and preterm birth.

PubMed

Bandoli, Gretchen; Palmsten, Kristin; Chambers, Christina D; Jelliffe-Pawlowski, Laura L; Baer, Rebecca J; Thompson, Caroline A

2018-05-21

A "Table Fallacy," as coined by Westreich and Greenland, reports multiple adjusted effect estimates from a single model. This practice, which remains common in published literature, can be problematic when different types of effect estimates are presented together in a single table. The purpose of this paper is to quantitatively illustrate this potential for misinterpretation with an example estimating the effects of preeclampsia on preterm birth. We analysed a retrospective population-based cohort of 2 963 888 singleton births in California between 2007 and 2012. We performed a modified Poisson regression to calculate the total effect of preeclampsia on the risk of PTB, adjusting for previous preterm birth. pregnancy alcohol abuse, maternal education, and maternal socio-demographic factors (Model 1). In subsequent models, we report the total effects of previous preterm birth, alcohol abuse, and education on the risk of PTB, comparing and contrasting the controlled direct effects, total effects, and confounded effect estimates, resulting from Model 1. The effect estimate for previous preterm birth (a controlled direct effect in Model 1) increased 10% when estimated as a total effect. The risk ratio for alcohol abuse, biased due to an uncontrolled confounder in Model 1, was reduced by 23% when adjusted for drug abuse. The risk ratio for maternal education, solely a predictor of the outcome, was essentially unchanged. Reporting multiple effect estimates from a single model may lead to misinterpretation and lack of reproducibility. This example highlights the need for careful consideration of the types of effects estimated in statistical models. © 2018 John Wiley & Sons Ltd.

Do the causes of infertility play a direct role in the aetiology of preterm birth?

PubMed

Messerlian, Carmen; Platt, Robert W; Ata, Baris; Tan, Seang-Lin; Basso, Olga

2015-03-01

It is well established that singletons born of assisted reproductive technology are at higher risk of preterm birth and other adverse outcomes. What remains unclear is whether the increased risk is attributable to the effects of the treatment alone or whether the underlying causes of infertility also play a role. The aim of this study was to examine whether any of the six categories of causes of infertility were associated with a direct effect on preterm birth using causal mediation analysis. We assembled a hospital-based cohort of births delivered at a large tertiary care hospital in Montreal, Canada between 2001 and 2007. Causes of infertility were ascertained through a clinical database and medical chart abstraction. We employed marginal structural models (MSM) to estimate the controlled direct effect of each cause of infertility on preterm birth compared with couples without the cause under examination. The final study cohort comprised 18,598 singleton and twin pregnancies, including 1689 in couples with ascertained infertility. MSM results suggested no significant direct effect for any of the six categories of causes. However, power was limited in smaller subgroup analyses, and a possible direct effect for uterine abnormalities (e.g. fibroids and malformations) could not be ruled out. In this cohort, most of the increased risk of preterm birth appeared to be explained by maternal characteristics (such as age, body mass index, and education) and by assisted reproduction. If these findings are corroborated, physicians should consider these risks when counselling patients. © 2015 John Wiley & Sons Ltd.

Australasian randomised trial to evaluate the role of maternal intramuscular dexamethasone versus betamethasone prior to preterm birth to increase survival free of childhood neurosensory disability (A*STEROID): study protocol.

PubMed

Crowther, Caroline A; Harding, Jane E; Middleton, Philippa F; Andersen, Chad C; Ashwood, Pat; Robinson, Jeffrey S

2013-05-03

Both dexamethasone and betamethasone, given to women at risk of preterm birth, substantially improve short-term neonatal health, increase the chance of the baby being discharged home alive, and reduce childhood neurosensory disability, remaining safe into adulthood. However, it is unclear which corticosteroid is of greater benefit to mother and child.This study aims to determine whether giving dexamethasone to women at risk of preterm birth at less than 34 weeks' gestation increases the chance of their children surviving free of neurosensory disability at two years' corrected age, compared with betamethasone. Design randomised, multicentre, placebo controlled trial.Inclusion criteria women at risk of preterm birth at less than 34 weeks' gestation with a singleton or twin pregnancy and no contraindications to the use of antenatal corticosteroids and who give informed consent.Trial entry & randomisation at telephone randomisation eligible women will be randomly allocated to either the dexamethasone group or the betamethasone group, allocated a study number and corresponding treatment pack.Study groups women in the dexamethasone group will be administered two syringes of 12 mg dexamethasone (dexamethasone sodium phosphate) and women in the betamethasone group will be administered two syringes of 11.4 mg betamethasone (Celestone Chronodose). Both study groups consist of intramuscular treatments 24 hours apart.Primary study outcome death or any neurosensory disability measured in children at two years' corrected age.Sample size a sample size of 1449 children is required to detect either a decrease in death or any neurosensory disability from 27.0% to 20.1% with dexamethasone compared with betamethasone, or an increase from 27.0% to 34.5% (two-sided alpha 0.05, 80% power, 5% loss to follow up, design effect 1.2). This study will provide high-level evidence of direct relevance for clinical practice. If one drug clearly results in significantly fewer deaths and fewer disabled children then it should be used consistently in women at risk of preterm birth and would be of great importance to women at risk of preterm birth, their children, health services and communities. ACTRN12608000631303.

Preventing preterm births: analysis of trends and potential reductions with interventions in 39 countries with very high human development index.

PubMed

Chang, Hannah H; Larson, Jim; Blencowe, Hannah; Spong, Catherine Y; Howson, Christopher P; Cairns-Smith, Sarah; Lackritz, Eve M; Lee, Shoo K; Mason, Elizabeth; Serazin, Andrew C; Walani, Salimah; Simpson, Joe Leigh; Lawn, Joy E

2013-01-19

Every year, 1·1 million babies die from prematurity, and many survivors are disabled. Worldwide, 15 million babies are born preterm (<37 weeks' gestation), with two decades of increasing rates in almost all countries with reliable data. The understanding of drivers and potential benefit of preventive interventions for preterm births is poor. We examined trends and estimate the potential reduction in preterm births for countries with very high human development index (VHHDI) if present evidence-based interventions were widely implemented. This analysis is to inform a rate reduction target for Born Too Soon. Countries were assessed for inclusion based on availability and quality of preterm prevalence data (2000-10), and trend analyses with projections undertaken. We analysed drivers of rate increases in the USA, 1989-2004. For 39 countries with VHHDI with more than 10,000 births, we did country-by-country analyses based on target population, incremental coverage increase, and intervention efficacy. We estimated cost savings on the basis of reported costs for preterm care in the USA adjusted using World Bank purchasing power parity. From 2010, even if all countries with VHHDI achieved annual preterm birth rate reductions of the best performers for 1990-2010 (Estonia and Croatia), 2000-10 (Sweden and Netherlands), or 2005-10 (Lithuania, Estonia), rates would experience a relative reduction of less than 5% by 2015 on average across the 39 countries. Our analysis of preterm birth rise 1989-2004 in USA suggests half the change is unexplained, but important drivers include non-medically indicated labour induction and caesarean delivery and assisted reproductive technologies. For all 39 countries with VHHDI, five interventions modelling at high coverage predicted a 5% relative reduction of preterm birth rate from 9·59% to 9·07% of livebirths: smoking cessation (0·01 rate reduction), decreasing multiple embryo transfers during assisted reproductive technologies (0·06), cervical cerclage (0·15), progesterone supplementation (0·01), and reduction of non-medically indicated labour induction or caesarean delivery (0·29). These findings translate to roughly 58,000 preterm births averted and total annual economic cost savings of about US$3 billion. We recommend a conservative target of a relative reduction in preterm birth rates of 5% by 2015. Our findings highlight the urgent need for research into underlying mechanisms of preterm births, and development of innovative interventions. Furthermore, the highest preterm birth rates occur in low-income settings where the causes of prematurity might differ and have simpler solutions such as birth spacing and treatment of infections in pregnancy than in high-income countries. Urgent focus on these settings is also crucial to reduce preterm births worldwide. March of Dimes, USA, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and National Institutes of Health, USA. Copyright © 2013 Elsevier Ltd. All rights reserved.

The distribution of clinical phenotypes of preterm birth syndrome: implications for prevention.

PubMed

Barros, Fernando C; Papageorghiou, Aris T; Victora, Cesar G; Noble, Julia A; Pang, Ruyan; Iams, Jay; Cheikh Ismail, Leila; Goldenberg, Robert L; Lambert, Ann; Kramer, Michael S; Carvalho, Maria; Conde-Agudelo, Agustin; Jaffer, Yasmin A; Bertino, Enrico; Gravett, Michael G; Altman, Doug G; Ohuma, Eric O; Purwar, Manorama; Frederick, Ihunnaya O; Bhutta, Zulfiqar A; Kennedy, Stephen H; Villar, José

2015-03-01

Preterm birth has been difficult to study and prevent because of its complex syndromic nature. To identify phenotypes of preterm delivery syndrome in the Newborn Cross-Sectional Study of the INTERGROWTH-21st Project. A population-based, multiethnic, cross-sectional study conducted at 8 geographically demarcated sites in Brazil, China, India, Italy, Kenya, Oman, the United Kingdom, and the United States. A total of 60,058 births over a 12-month fixed period between April 27, 2009, and March 2, 2014. Of these, 53,871 had an ultrasonography estimate of gestational age, among which 5828 were preterm births (10.8%). Pregnancies were prospectively studied using a standardized data collection and online data management system. Newborns had anthropometric and clinical examinations using standardized methods and identical equipment and were followed up until hospital discharge. The main study outcomes were clusters of preterm phenotypes and for each cluster, we analyzed signs of presentation at hospital admission, admission rates for neonatal intensive care for 7 days or more, and neonatal mortality rates. Twelve preterm birth clusters were identified using our conceptual framework. Eleven consisted of combinations of conditions known to be associated with preterm birth, 10 of which were dominated by a single condition. However, the most common single cluster (30.0% of the total preterm cases; n = 1747) was not associated with any severe maternal, fetal, or placental condition that was clinically detectable based on the information available; within this cluster, many cases were caregiver initiated. Only 22% (n = 1284) of all the preterm births occurred spontaneously without any of these severe conditions. Maternal presentation on hospital admission, newborn anthropometry, and risk for death before hospital discharge or admission for 7 or more days to a neonatal intensive care unit, none of which were used to construct the clusters, also differed according to the identified phenotypes. The prevalence of preterm birth ranged from 8.2% in Muscat, Oman, and Oxford, England, to 16.6% in Seattle, Washington. We identified 12 preterm birth phenotypes associated with different patterns of neonatal outcomes. In 22% of all preterm births, parturition started spontaneously and was not associated with any of the phenotypic conditions considered. We believe these results contribute to an improved understanding of this complex syndrome and provide an empirical basis to focus research on a more homogenous set of phenotypes.

Preterm birth and oxidative stress: Effects of acute physical exercise and hypoxia physiological responses.

PubMed

Martin, Agnès; Faes, Camille; Debevec, Tadej; Rytz, Chantal; Millet, Grégoire; Pialoux, Vincent

2018-05-01

Preterm birth is a global health issue that can induce lifelong medical sequela. Presently, at least one in ten newborns are born prematurely. At birth, preterm newborns exhibit higher levels of oxidative stress (OS) due to the inability to face the oxygen rich environment in which they are born into. Moreover, their immature respiratory, digestive, immune and antioxidant defense systems, as well as the potential numerous medical interventions following a preterm birth, such as oxygen resuscitation, nutrition, phototherapy and blood transfusion further contribute to high levels of OS. Although the acute effects seem well established, little is known regarding the long-term effects of preterm birth on OS. This matter is especially important given that chronically elevated OS levels may persist into adulthood and consequently contribute to the development of numerous non-communicable diseases observed in people born preterm such as diabetes, hypertension or lung disorders. The purpose of this review is to summarize the current knowledge regarding the consequences of preterm birth on OS levels from newborn to adulthood. In addition, the effects of physical activity and hypoxia, both known to disrupt redox balance, on OS modulation in preterm individuals are also explored. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Impact of perinatal factors on growth deficits of preterm infants.

PubMed

Goulart, Ana Lucia; Morais, Mauro Batista de; Kopelman, Benjamin Israel

2011-01-01

To review perinatal factors associated with a growth deficit in preterm infants at a corrected age of one year. Cohort study of preterm infants with a birth weight < 2,000 g. Percentiles and Z scores of body weight (W/A), length (L/A) and head circumference (HC/A) at one year of corrected age were calculated by using the Centers for Disease Control and Prevention curves. Among 303 preterm infants, the frequencies of measures below the 10th percentile (P10) and Z scores -2 were 43.2% and 24.4% for W/A, 22.1% and 8.6% for L/A and 15.8% and 4.6% for HC/A, respectively. Logistic regression analyses showed factors associated with higher odds for W/A < P10 were resuscitation at birth (1.8 times) and small for gestational age infants (3.0 times). In infants rated as small at full-term postconceptual age, the odds for W/A < P10 were 4.0 times as high in those with a birth weight between 1,000 and 1,499 g and 3.5 times as high in those > 1,500 g. As birth length was reduced, the odds for L/A < P10 increased, but this was not associated with birth weight. The odds for HC/A < P10 were 2.5 times as high in small for gestational age infants. In infants with a body weight < 1,000 g, the odds for HC/A < P10 were 4.4 times higher, compared with those between 1,000 g and 1,499 g and 5.3 times higher if compared with those > 1,500 g. At a corrected age of one year, preterm infants with a birth weight < 2,000 g were found with high growth deficits frequencies, and associated factors were variable, depending on the analyzed deficit, with intrauterine and postnatal growth restriction being outstanding predictors.

Implementation of a Nutrition Program Reduced Post-Discharge Growth Restriction in Thai Very Low Birth Weight Preterm Infants.

PubMed

Japakasetr, Suchada; Sirikulchayanonta, Chutima; Suthutvoravut, Umaporn; Chindavijak, Busba; Kagawa, Masaharu; Nokdee, Somjai

2016-12-17

Very low birth weight (VLBW) preterm infants are vulnerable to growth restriction after discharge due to cumulative protein and energy deficits during their hospital stay and early post-discharge period. The current study evaluated the effectiveness of the preterm infant, post-discharge nutrition (PIN) program to reduce post-discharge growth restriction in Thai VLBW preterm infants. A prospective, non-randomized interventional cohort study was undertaken to assess the growth of 22 VLBW preterm infants who received the PIN program and compared them with 22 VLBW preterm infants who received conventional nutrition services. Infant's growth was recorded monthly until the infants reached six months' corrected age (6-moCA). Intervention infants had significantly greater body weights ( p = 0.013) and head circumferences ( p = 0.009). Also, a greater proportion of the intervention group recovered their weight to the standard weight at 4-moCA ( p = 0.027) and at 6-moCA ( p = 0.007) and their head circumference to the standard head circumference at 6-moCA ( p = 0.004) compared to their historical comparison counterparts. Enlistment in the PIN program thus resulted in significantly reduced post-discharge growth restriction in VLBW preterm infants. Further research on longer term effects of the program on infant's growth and development is warranted.

Species of fine particulate matter and the risk of preterm birth

EPA Science Inventory

Particulate matter (PM) has been variably associated with preterm birth (PTB), but the roles of PM species have been less studied. We estimated risk of birth in 4 preterm categories (risks reported as PTBs per 106 pregnancies; PTB categories = gestational age of 20-27; 28-31; 32-...

Prevention of preterm birth: harnessing science to address the global epidemic.

PubMed

Rubens, Craig E; Sadovsky, Yoel; Muglia, Louis; Gravett, Michael G; Lackritz, Eve; Gravett, Courtney

2014-11-12

Preterm birth is a leading cause of infant morbidity and mortality worldwide, but current interventions to prevent prematurity are largely ineffective. Preterm birth is increasingly recognized as an outcome that can result from a variety of pathological processes. Despite current research efforts, the mechanisms underlying these processes remain poorly understood and are influenced by a range of biological and environmental factors. Research with modern techniques is needed to understand the mechanisms responsible for preterm labor and birth and identify targets for diagnostic and therapeutic solutions. This review evaluates the state of reproductive science relevant to understanding the causes of preterm birth, identifies potential targets for prevention, and outlines challenges and opportunities for translating research findings into effective interventions. Copyright © 2014, American Association for the Advancement of Science.

Environmental contaminant exposures and preterm birth: A comprehensive review

PubMed Central

Ferguson, Kelly K.; O’Neill, Marie S.; Meeker, John D.

2013-01-01

Preterm birth is a significant public health concern, as it is associated with high risk of infant mortality, various morbidities in both the neonatal period and later in life, and a significant societal economic burden. As many cases are of unknown etiology, identification of the contribution of environmental contaminant exposures is a priority in the study of preterm birth. This is a comprehensive review of all known studies published from 1992 through August 2012 linking maternal exposure to environmental chemicals during pregnancy with preterm birth. Using PubMed searches studies were identified that examined associations between preterm birth and exposure to 5 categories of environmental toxicants, including persistent organic pollutants, drinking water contaminants, atmospheric pollutants, metals and metalloids, and other environmental contaminants. Individual studies were summarized and specific suggestions made for future work in regard to exposure and outcome assessment methods as well as study design, with the recommendation of focusing on potential mediating toxicological mechanisms. In conclusion, no consistent evidence was found for positive associations between individual chemical exposures and preterm birth. By identifying limitations and addressing the gaps that may have impeded the ability to identify true associations thus far, this review can guide future epidemiologic studies of environmental exposures and preterm birth. PMID:23682677

Pregnant Women With Posttraumatic Stress Disorder and Risk of Preterm Birth

PubMed Central

Yonkers, Kimberly Ann; Smith, Megan V.; Forray, Ariadna; Epperson, C. Neill; Costello, Darce; Lin, Haiqun; Belanger, Kathleen

2014-01-01

IMPORTANCE Posttraumatic stress disorder (PTSD) occurs in about 8% of pregnant women. Stressful conditions, including PTSD, are inconsistently linked to preterm birth. Psychotropic treatment has been frequently associated with preterm birth. Identifying whether the psychiatric illness or its treatment is independently associated with preterm birth may help clinicians and patients when making management decisions. OBJECTIVE To determine whether a likely diagnosis of PTSD or antidepressant and benzodiazepine treatment during pregnancy is associated with risk of preterm birth. We hypothesized that pregnant women who likely had PTSD and women receiving antidepressant or anxiolytic treatment would be more likely to experience preterm birth. DESIGN, SETTING, AND PARTICIPANTS Longitudinal, prospective cohort study of 2654 women who were recruited before 17 completed weeks of pregnancy from 137 obstetrical practices in Connecticut and Western Massachusetts. EXPOSURES Posttraumatic stress disorder, major depressive episode, and use of antidepressant and benzodiazepine medications. MAIN OUTCOMES AND MEASURES Preterm birth, operationalized as delivery prior to 37 completed weeks of pregnancy. Likely psychiatric diagnoses were generated through administration of the Composite International Diagnostic Interview and the Modified PTSD Symptom Scale. Data on medication use were gathered at each participant interview. RESULTS Recursive partitioning analysis showed elevated rates of preterm birth among women with PTSD. A further split of the PTSD node showed high rates for women who met criteria for a major depressive episode, which suggests an interaction between these 2 exposures. Logistic regression analysis confirmed risk for women who likely had both conditions (odds ratio [OR], 4.08 [95% CI, 1.27–13.15]). For each point increase on the Modified PTSD Symptom Scale (range, 0–110), the risk of preterm birth increased by 1% to 2%. The odds of preterm birth are high for women who used a serotonin reuptake inhibitor (OR, 1.55 [95% CI, 1.02–2.36]) and women who used a benzodiazepine medication (OR, 1.99 [95% CI, 0.98–4.03]). CONCLUSIONS AND RELEVANCE Women with likely diagnoses of both PTSD and a major depressive episode are at a 4-fold increased risk of preterm birth; this risk is greater than, and independent of, antidepressant and benzodiazepine use and is not simply a function of mood or anxiety symptoms. PMID:24920287

The effects of preterm birth and its antecedents on the cardiovascular system.

PubMed

Bensley, Jonathan G; De Matteo, Robert; Harding, Richard; Black, Mary J

2016-06-01

Preterm birth occurs in approximately 10% of all births worldwide. It prematurely exposes the developing cardiovascular system to the hemodynamic transition that occurs at birth and to the subsequent functional demands of life ex utero. This review describes the current knowledge of the effects of preterm birth, and some of its common antecedents (chorioamnionitis, intra-uterine growth restriction, and maternal antenatal corticosteroid administration), on the structure of the myocardium. A thorough literature search was conducted for articles relating to how preterm birth, and its antecedents, affect development of the heart. Given that sheep are an excellent model for the studies of cardiac development, this review has focused on experimental studies in sheep as well as clinical findings. Our review of the literature demonstrates that individuals born preterm are at an increased risk of cardiovascular disease later in life, including increased mean arterial pressure, abnormally shaped and sub-optimally performing hearts and changes in the vasculature. The review highlights how antenatal corticosteroids, intra-uterine growth restriction, and exposure to chorioamnionitis also have the potential to impact cardiac growth in the preterm newborn. Preterm birth and its common antecedents (antenatal corticosteroids, intra-uterine growth restriction, and chorioamnionitis) have the potential to adversely impact cardiac structure immediately following birth and in later life. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

Employment, working conditions, and preterm birth: results from the Europop case-control survey.

PubMed

Saurel-Cubizolles, M J; Zeitlin, J; Lelong, N; Papiernik, E; Di Renzo, G C; Bréart, G

2004-05-01

To analyse the relation between preterm birth and working conditions in Europe using common measures of exposure and to test whether employment related risks varied by country of residence. A case-control study in which cases included all consecutive singleton preterm births and controls included one of every ten singleton term births in each participating maternity unit. Data about working conditions were obtained by interview from women after delivery. Sixteen European countries. The analysis included 5145 preterm and 7911 term births of which 2369 preterm and 4098 term births were to women employed during pregnancy. Analyses of working conditions were carried out for women working through at least the third month of pregnancy. Employed women did not have an excess risk of preterm birth. Among working women, a moderate excess risk was observed for women working more than 42 hours a week (OR = 1.33, CI = 1.1 to 1.6), standing more than six hours a day (OR = 1.26, CI = 1.1 to 1.5), and for women with low job satisfaction (OR = 1.27, CI = 1.1 to 1.5). There were stronger links in countries with a lower overall level of perinatal health and a common practice of long prenatal leaves. These findings show that specific working conditions affect the risk of preterm birth. They also suggest employment related risks could be mediated by the social and legislative context.

Fetal exposure to lead during pregnancy and the risk of preterm and early-term deliveries.

PubMed

Cheng, Lu; Zhang, Bin; Huo, Wenqian; Cao, Zhongqiang; Liu, Wenyu; Liao, Jiaqiang; Xia, Wei; Xu, Shunqing; Li, Yuanyuan

2017-08-01

Studies have reported the association between lead exposure during pregnancy and preterm birth. However, findings are still inconsistent. This prospective birth cohort study evaluated the risks of preterm and early-term births and its association with prenatal lead exposure in Hubei, China. A total of 7299 pregnant women were selected from the Healthy Baby Cohort. Maternal urinary lead levels were measured by the Inductively Coupled Plasma Mass Spectrometry. The associations between tertiles of urinary lead levels and the risks of preterm and early-term deliveries were assessed using multiple logistic regression models. The geometric mean of creatinine-adjusted urinary lead concentrations among all participating mothers, preterm birth, and early-term birth were 3.19, 3.68, and 3.17μg/g creatinine, respectively. A significant increase in the risk of preterm births was associated with the highest urinary lead tertile after adjusting for confounders with odds ratio (OR) of 1.96. The association was more pronounced among 25-36 years old mothers with OR of 2.03. Though significant p trends were observed between lead exposure (medium and high tertiles) and the risk of early-term births, their ORs were not significant. Our findings indicate that the risk of preterm birth might increase with higher fetal lead exposure, particularly among women between the age of 25 and 36 years. Copyright © 2017 Elsevier GmbH. All rights reserved.

Increase in Preterm Birth during Demographic Transition in Chile from 1991 to 2012

PubMed Central

López Orellana, Paulina

2015-01-01

Introduction. Universally mothers at 35 years or more have had higher maternal and perinatal risks. This study analyzed the trend of this group in maternal population and determined their risk of having premature children, during the demographic transition period in Chile. Materials and Methods. Epidemiological study conducted in the population of simple live births registered in the Chilean National Database Births of 1991–2012. Analyses were performed in three categories of maternal age: 35 or more, under 35, and 20 to 29 years. The risk of prematurity was measured by crude and Adjusted Odds Ratio from logistic regression model. Results. Mothers aged 35 and older increased in population from 10.6% in 1991 to 16.7% in 2012 and presented an overall prevalence of preterm delivery of 6.7%, higher prevalence than 20–29 age group (4.7%). In aging mothers, the Odds Ratio for preterm birth adjusted for education, marital status, and parity was 1.68 (95% CI (1.66–1.70)) compared to mothers aged 20–29. All differences were significant (p < 0.001). Conclusions. During Chilean demographic transition, mothers aged 35 or older increased steadily and significantly maintaining higher risks of preterm births. Policies to prevent and monitor the late motherhood could contribute to stopping the current trend. PMID:26413549

Income-related and educational inequality in small-for-gestational age and preterm birth in Denmark and Finland 1987-2003.

PubMed

Mortensen, Laust H; Lauridsen, Jørgen T; Diderichsen, Finn; Kaplan, George A; Gissler, Mika; Andersen, Anne-Marie N

2010-02-01

In this paper, we examine income- and education-related inequality in small-for-gestational age (SGA) and preterm birth in Denmark and Finland from 1987 to 2003 using concentration indexes (CIXs). From the national medical birth registries we gathered information on all births from 1987 to 2003. Information on highest completed maternal education and household income in the year preceding birth of the offspring was obtained for 1,012,400 births in Denmark and 499,390 in Finland. We then calculated CIXs for income- and education-related inequality in SGA and preterm birth. The mean household income-related inequality in SGA was -0.04 (95% confidence interval: -0.05, -0.04) in Denmark and -0.03 (-0.04, -0.02) in Finland. The maternal education-related inequality in SGA was -0.08 (-0.10, -0.06) in Denmark and -0.07 (-0.08, -0.06) in Finland. The income-related inequality in preterm birth was -0.03 (-0.03, -0.02) in Denmark and -0.03 (-0.04, -0.02) in Finland. The education-related inequality in preterm birth was -0.05 (-0.07, -0.04) in Denmark and -0.04 (-0.05, -0.03) in Finland. In Denmark, the income-related and education-related inequity in SGA increased over time. In Finland, the income-related inequality in SGA birth increased slightly, while education-related inequalities remained stable. Inequalities in preterm birth decreased over time in both countries. Denmark and Finland are examples of nations with free prenatal care and publicly financed obstetric care of high quality. During the period of study there were macroeconomic shocks affecting both countries. However, only small income- and education-related inequalities in SGA and preterm births during the period were observed.

Comparison at 32-37 Weeks Postconception of Infants Born 1983-1989 and 1995-2004 on the Neurobehavioral Assessment of the Preterm Infant

ERIC Educational Resources Information Center

Brown, Josephine V.; Bakeman, Roger; Sampers, Jackie S.; Korner, Anneliese F.; Constantinou, Janet C.; Anand, K. J. S.

2008-01-01

In spite of numerous recent outcome studies of extremely low birth weight (ELBW) infants, no data exist on their development prior to term. In this study we traced and compared the neurobehavioral development of 251 ELBW (less than 1,000 g) and 240 low birth weight (LBW; 1,000 g-2,500 g) preterms born between 1995 and 2004 from 32 to 37 weeks…

Downward economic mobility and preterm birth: an exploratory study of Chicago-born upper class White mothers.

PubMed

Collins, James W; Rankin, Kristin M; David, Richard J

2015-07-01

A paucity of published data exists on the factors underlying the relatively poor birth outcome of non-Hispanic White women in the United States. To determine whether downward economic mobility is a risk factor for preterm birth (<37 weeks, PTB) among upper class-born White women. Stratified and multilevel logistic regression analyses were performed on an Illinois transgenerational dataset of non-Hispanic White infants (1989-1991) and their women (1956-1976) with appended US census income information. The study sample was restricted to singleton births of Chicago-born upper-class (defined by early-life residence in affluent neighborhoods) non-Hispanic White women. Upper class-born White women (n = 4,891) who did not experience downward economic mobility by the time of delivery had a PTB rate of 5.4 %. Those women who experienced slight (n = 5,112), moderate (n = 2,158), or extreme (n = 339) downward economic mobility had PTB rates of 6.5, 8.5, and 10.1 %, respectively; RR (95 % CI) = 1.2 (1.0-4.0), 1.6 (1.3-1.9), and 1.9 (1.3-2.6), respectively. Maternal downward economic mobility was also associated with an increased prevalence of biologic, medical, and behavioral risk factors. Interestingly, the relationship between moderate to extreme downward mobility and preterm birth was stronger among former low birth weight (<2500 g, LBW) than non-LBW women: 2.8 (1.4-5.8) versus 1.6 (1.3-1.9), respectively. In multilevel logistic regression models, the adjusted odds ratio of preterm birth for former LBW and non-LBW women who experienced any downward mobility (compared to those women with lifelong upper class status) equaled 2.4 (1.1-5.3) and 1.1 (1.0-1.1), respectively. Downward economic mobility is associated with an increased risk of preterm birth among upper class-born White urban women; this phenomenon is strongest among former low birth weight women.

Genomics of Preterm Birth

PubMed Central

Swaggart, Kayleigh A.; Pavlicev, Mihaela; Muglia, Louis J.

2015-01-01

The molecular mechanisms controlling human birth timing at term, or resulting in preterm birth, have been the focus of considerable investigation, but limited insights have been gained over the past 50 years. In part, these processes have remained elusive because of divergence in reproductive strategies and physiology shown by model organisms, making extrapolation to humans uncertain. Here, we summarize the evolution of progesterone signaling and variation in pregnancy maintenance and termination. We use this comparative physiology to support the hypothesis that selective pressure on genomic loci involved in the timing of parturition have shaped human birth timing, and that these loci can be identified with comparative genomic strategies. Previous limitations imposed by divergence of mechanisms provide an important new opportunity to elucidate fundamental pathways of parturition control through increasing availability of sequenced genomes and associated reproductive physiology characteristics across diverse organisms. PMID:25646385

Maternal Dietary Nutrient Intake and Its Association  with Preterm Birth: A Case-control Study in Beijing,  China.

PubMed

Zhang, Yan; Zhou, Hong; Perkins, Anthony; Wang, Yan; Sun, Jing

2017-03-01

This study aimed to evaluate dietary nutrient intake among Chinese pregnant women by comparison with Chinese Dietary Reference Intakes (DRIs) and to explore the association between dietary nutrients and preterm birth. A case-control design was conducted in Beijing with 130 preterm delivery mothers in case group and 381 term delivery mothers in control group. Information on mothers' diet was collected using a food frequency questionnaire, and nutrients and energy intakes were subsequently calculated based on DRIs. Multivariate analysis of variance was used to compare the differences between term and preterm groups in relation to dietary nutrients. Dietary nutrient intakes were imbalanced in both groups compared with Chinese DRIs. Preterm delivery mothers had a lower level of fat and vitamin E intake than term delivery mothers (p < 0.05). Multivariate analysis showed lower vitamin E intake in preterm delivery mothers with a prepregnancy BMI < 18.5 kg/m2 (p < 0.05) and higher carbohydrate intake in preterm delivery mothers with prepregnancy BMI ≥ 24 kg/m2 (p < 0.05). An imbalanced diet in both groups and low level of dietary intakes of fat and vitamin E in preterm group suggest health education measures should be taken to improve the dietary quality of pregnant women, especially for those with an abnormal prepregnancy BMI.

Validation of maternal reports for low birthweight and preterm birth indicators in rural Nepal.

PubMed

Chang, Karen T; Mullany, Luke C; Khatry, Subarna K; LeClerq, Steven C; Munos, Melinda K; Katz, Joanne

2018-06-01

Tracking progress towards global newborn health targets depends largely on maternal reported data collected through large, nationally representative surveys. We evaluated the validity, across a range of recall period lengths (1 to 24 months post-delivery), of maternal report of birthweight, birth size and length of pregnancy. We compared maternal reports to reference standards of birthweights measured within 72 hours of delivery and gestational age generated from reported first day of the last menstrual period (LMP) prospectively collected as part of a population-based study (n = 1502). We calculated sensitivity, specificity, area the under the receiver operating curve (AUC) as a measure of individual-level accuracy, and the inflation factor (IF) to quantify population-level bias for each indicator. We assessed if length of recall period modified accuracy by stratifying measurements across time bins and using a modified Poisson regression with robust error variance to estimate the relative risk (RR) of correctly classifying newborns as low birthweight (LBW) or preterm, adjusting for child sex, place of delivery, maternal age, maternal education, parity, and ethnicity. The LBW indicator using maternally reported birthweight in grams had low individual-level accuracy (AUC = 0.69) and high population-level bias (inflation factor IF = 0.62). LBW using maternally reported birth size and the preterm birth indicator had lower individual-level accuracy (AUC = 0.58 and 0.56, respectively) and higher population-level bias (IF = 0.28 and 0.35, respectively) up to 24 months following birth. Length of recall time did not affect accuracy of LBW indicators. For the preterm birth indicator, accuracy did not change with length of recall up to 20 months after birth and improved slightly beyond 20 months. The use of maternal reports may underestimate and bias indicators for LBW and preterm birth. In settings with high prevalence of LBW and preterm births, these indicators generated from maternal reports may be more vulnerable to misclassification. In populations where an important proportion of births occur at home or where weight is not routinely measured, mothers perhaps place less importance on remembering size at birth. Further work is needed to explore whether these conclusions on the validity of maternal reports hold in similar rural and low-income settings.

Influence of maternal breast milk ingestion on acquisition of the intestinal microbiome in preterm infants.

PubMed

Gregory, Katherine E; Samuel, Buck S; Houghteling, Pearl; Shan, Guru; Ausubel, Frederick M; Sadreyev, Ruslan I; Walker, W Allan

2016-12-30

The initial acquisition and early development of the intestinal microbiome during infancy are important to human health across the lifespan. Mode of birth, antibiotic administration, environment of care, and nutrition have all been shown to play a role in the assembly of the intestinal microbiome during early life. For preterm infants, who are disproportionately at risk of inflammatory intestinal disease (i.e., necrotizing enterocolitis), a unique set of clinical factors influence the establishment of the microbiome. The purpose of this study was to establish the influence of nutritional exposures on the intestinal microbiome in a cohort of preterm infants early in life. Principal component analysis of 199 samples from 30 preterm infants (<32 weeks) over the first 60 days following birth showed that the intestinal microbiome was influenced by postnatal time (p < 0.001, R 2  = 0.13), birth weight (p < 0.001, R 2  = 0.08), and nutrition (p < 0.001, R 2  = 0.21). Infants who were fed breast milk had a greater initial bacterial diversity and a more gradual acquisition of diversity compared to infants who were fed infant formula. The microbiome of infants fed breast milk were more similar regardless of birth weight (p = 0.049), in contrast to the microbiome of infants fed infant formula, which clustered differently based on birth weight (p < 0.001). By adjusting for differences in gut maturity, an ordered succession of microbial phylotypes was observed in breast milk-fed infants, which appeared to be disrupted in those fed infant formula. Supplementation with pasteurized donor human milk was partially successful in promoting a microbiome more similar to breast milk-fed infants and moderating rapid increases in bacterial diversity. The preterm infant intestinal microbiome is influenced by postnatal time, birth weight, gestational age, and nutrition. Feeding with breast milk appears to mask the influence of birth weight, suggesting a protective effect against gut immaturity in the preterm infant. These findings suggest not only a microbial mechanism underpinning the body of evidence showing that breast milk promotes intestinal health in the preterm infant but also a dynamic interplay of host and dietary factors that facilitate the colonization of and enrichment for specific microbes during establishment of the preterm infant microbiota.

The Growing Trend of Moderate Preterm Births: An Ecological Study in One Region of Brazil

PubMed Central

Melo, Emiliana Cristina; Falavina, Larissa Pereira

2015-01-01

Background Preterm birth is a serious public health problem, as it is linked to high rates of neonatal and child morbidity and mortality, with Brazil listed among the countries with the ten highest numbers of premature births. Nonetheless, knowledge is scarce regarding prematurity and associated factors in mid-sized cities. The objective of this study was to analyze the trend of preterm births and associated factors in a municipality located in the state of Paraná, Brazil. Methods This was an ecological time series study of births recorded into the Live Birth Information System for residents of Maringá, Paraná, Brazil, between 2000 and 2013. The polynomial regression model was used for trend analysis of preterm birth, characteristics of the mother, gestation and delivery, and newborn. The association with preterm birth was analyzed using odds ratio (OR). Results A total of 61,634 live births were analyzed, of which 5,632 were preterm births. Prematurity increased from 7.9% in 2000 to 11.2% in 2013 –an average increase of 0.54% per year (r2 = 0.93)–with a growing share of moderate preterm births (32 to <37 weeks), which rose from 7.0% in 2000 to 9.7% in 2013. Between 2011 and 2013, multiple pregnancy (OR = 16.64; CI = 13.24–20.92), inadequate number of prenatal visits (OR = 2.81; CI = 2.51–3.15), Apgar score below 7 at 1 (OR = 4.07; CI = 3.55–4.67) and 5 minutes (OR = 10.88; CI = 7.71–15.36), low birth weight (OR = 38.75; CI = 33.72–44.55) and congenital malformations (OR = 3.18; CI = 2.14–4.74) were associated with preterm birth. A growing trend was observed for multiple pregnancies, with an average annual increase of 0.32% (r2 = 0.90), as well as for C-section birth (2.38% yearly increase). Of all newborn characteristics, Apgar score below 7 at 5 minutes (-0.19% per year) and low birth weight (-1.43%) decreased, whereas congenital malformations rose (0.20% per year). Conclusions Efforts are required to prevent premature delivery, particularly during the moderate period, as well as greater care during the prenatal period towards expectant mothers bearing multiple pregnancies, birth defects, in addition to reducing C-section birth as it may be linked to preterm birth. PMID:26529097

The association of neighborhood social capital and ethnic (minority) density with pregnancy outcomes in the Netherlands.

PubMed

Schölmerich, Vera L N; Erdem, Özcan; Borsboom, Gerard; Ghorashi, Halleh; Groenewegen, Peter; Steegers, Eric A P; Kawachi, Ichiro; Denktaş, Semiha

2014-01-01

Perinatal morbidity rates are relatively high in the Netherlands, and significant inequalities in perinatal morbidity and mortality can be found across neighborhoods. In socioeconomically deprived areas, 'Western' women are particularly at risk for adverse birth outcomes. Almost all studies to date have explained the disparities in terms of individual determinants of birth outcomes. This study examines the influence of neighborhood contextual characteristics on birth weight (adjusted for gestational age) and preterm birth. We focused on the influence of neighborhood social capital--measured as informal socializing and social connections between neighbors--as well as ethnic (minority) density. Data on birth weight and prematurity were obtained from the Perinatal Registration Netherlands 2000-2008 dataset, containing 97% of all pregnancies. Neighborhood-level measurements were obtained from three different sources, comprising both survey and registration data. We included 3.422 neighborhoods and 1.527.565 pregnancies for the birth weight analysis and 1.549.285 pregnancies for the premature birth analysis. Linear and logistic multilevel regression was performed to assess the associations of individual and neighborhood level variables with birth weight and preterm birth. We found modest but significant neighborhood effects on birth weight and preterm births. The effect of ethnic (minority) density was stronger than that of neighborhood social capital. Moreover, ethnic (minority) density was associated with higher birth weight for infants of non-Western ethnic minority women compared to Western women (15 grams; 95% CI: 12,4/17,5) as well as reduced risk for prematurity (OR 0.97; CI 0,95/0,99). Our results indicate that neighborhood contexts are associated with birth weight and preterm birth in the Netherlands. Moreover, ethnic (minority) density seems to be a protective factor for non-Western ethnic minority women, but not for Western women. This helps explain the increased risk of Western women in deprived neighborhoods for adverse birth outcomes found in previous studies.

The Association of Neighborhood Social Capital and Ethnic (Minority) Density with Pregnancy Outcomes in the Netherlands

PubMed Central

Schölmerich, Vera L. N.; Erdem, Özcan; Borsboom, Gerard; Ghorashi, Halleh; Groenewegen, Peter; Steegers, Eric A. P.; Kawachi, Ichiro; Denktaş, Semiha

2014-01-01

Background Perinatal morbidity rates are relatively high in the Netherlands, and significant inequalities in perinatal morbidity and mortality can be found across neighborhoods. In socioeconomically deprived areas, ‘Western’ women are particularly at risk for adverse birth outcomes. Almost all studies to date have explained the disparities in terms of individual determinants of birth outcomes. This study examines the influence of neighborhood contextual characteristics on birth weight (adjusted for gestational age) and preterm birth. We focused on the influence of neighborhood social capital – measured as informal socializing and social connections between neighbors – as well as ethnic (minority) density. Methods Data on birth weight and prematurity were obtained from the Perinatal Registration Netherlands 2000–2008 dataset, containing 97% of all pregnancies. Neighborhood-level measurements were obtained from three different sources, comprising both survey and registration data. We included 3.422 neighborhoods and 1.527.565 pregnancies for the birth weight analysis and 1.549.285 pregnancies for the premature birth analysis. Linear and logistic multilevel regression was performed to assess the associations of individual and neighborhood level variables with birth weight and preterm birth. Results We found modest but significant neighborhood effects on birth weight and preterm births. The effect of ethnic (minority) density was stronger than that of neighborhood social capital. Moreover, ethnic (minority) density was associated with higher birth weight for infants of non-Western ethnic minority women compared to Western women (15 grams; 95% CI: 12,4/17,5) as well as reduced risk for prematurity (OR 0.97; CI 0,95/0,99). Conclusions Our results indicate that neighborhood contexts are associated with birth weight and preterm birth in the Netherlands. Moreover, ethnic (minority) density seems to be a protective factor for non-Western ethnic minority women, but not for Western women. This helps explain the increased risk of Western women in deprived neighborhoods for adverse birth outcomes found in previous studies. PMID:24806505

The influence of season and ambient temperature on birth outcomes: a review of the epidemiological literature.

PubMed

Strand, Linn B; Barnett, Adrian G; Tong, Shilu

2011-04-01

Seasonal patterns of birth outcomes, such as low birth weight, preterm birth and stillbirth, have been found around the world. As a result, there has been an increasing interest in evaluating short-term exposure to ambient temperature as a determinant of adverse birth outcomes. This paper reviews the epidemiological evidence on seasonality of birth outcomes and the impact of prenatal exposure to ambient temperature on birth outcomes. We identified 20 studies that investigated seasonality of birth outcomes, and reported statistically significant seasonal patterns. Most of the studies found peaks of preterm birth, stillbirth and low birth weight in winter, summer or both, which indicates the extremes of temperature may be an important determinant of poor birth outcomes. We identified 13 studies that investigated the influence of exposure to ambient temperature on birth weight and preterm birth (none examined stillbirth). The evidence for an adverse effect of high temperatures was stronger for birth weight than for preterm birth. More research is needed to clarify whether high temperatures have a causal effect on fetal health. Copyright © 2011 Elsevier Inc. All rights reserved.

Posttraumatic stress disorder and risk of spontaneous preterm birth.

PubMed

Shaw, Jonathan G; Asch, Steven M; Kimerling, Rachel; Frayne, Susan M; Shaw, Kate A; Phibbs, Ciaran S

2014-12-01

To evaluate the association between antenatal posttraumatic stress disorder (PTSD) and spontaneous preterm delivery. We identified antenatal PTSD status and spontaneous preterm delivery in a retrospective cohort of 16,334 deliveries covered by the Veterans Health Administration from 2000 to 2012. We divided mothers with PTSD into those with diagnoses present the year before delivery (active PTSD) and those only with earlier diagnoses (historical PTSD). We identified spontaneous preterm birth and potential confounders including age, race, military deployment, twins, hypertension, substance use, depression, and results of military sexual trauma screening and then performed multivariate regression to estimate adjusted odds ratio (OR) of spontaneous preterm delivery as a function of PTSD status. Of 16,334 births, 3,049 (19%) were to mothers with PTSD diagnoses, of whom 1,921 (12%) had active PTSD. Spontaneous preterm delivery was higher in those with active PTSD (9.2%, n=176) than those with historical (8.0%, n=90) or no PTSD (7.4%, n=982) before adjustment (P=.02). The association between PTSD and preterm birth persisted, when adjusting for covariates, only in those with active PTSD (adjusted OR 1.35, 95% confidence interval [CI] 1.14-1.61). Analyses adjusting for comorbid psychiatric and medical diagnoses revealed the association with active PTSD to be robust. In this cohort, containing an unprecedented number of PTSD-affected pregnancies, mothers with active PTSD were significantly more likely to suffer spontaneous preterm birth with an attributable two excess preterm births per 100 deliveries (95% CI 1-4). Posttraumatic stress disorder's health effects may extend, through birth outcomes, into the next generation.

Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort1234

PubMed Central

Bodnar, Lisa M; Olsen, Jorn; Olsen, Sjurdur; Nohr, Ellen A

2011-01-01

Background: The intake of periconceptional multivitamins may decrease the risk of preterm births (PTBs) or small-for-gestational-age (SGA) births. Objective: We related the timing and frequency of periconceptional multivitamin use to SGA births and PTBs and its clinical presentations (ie, preterm labor, premature rupture of membranes, and medical induction). Design: Women in the Danish National Birth Cohort (n = 35,897) reported the number of weeks of multivitamin use during a 12-wk periconceptional period. Cox regression was used to estimate the relation between any multivitamin use and PTBs (<37 wk) or SGA births (birth weight adjusted for gestational age >2 SDs below the mean on the basis of fetal growth curves). The timing (preconception and postconception) and frequency of use were also analyzed. Regular users (4–6 wk) and partial users (1–3 wk) in each period were compared with nonusers. Results: The association between periconceptional multivitamin use and PTBs varied according to prepregnancy overweight status (P-interaction = 0.07). Regular preconception and postconception multivitamin use in women with a prepregnancy BMI (in kg/m2) <25 was associated with reduced risks of a PTB (HR: 0.84; 95% CI: 0.73, 0.95) and preterm labor (HR: 0.80; 95% CI: 0.69, 0.94). No similar associations were shown for overweight women. The adjusted risk of an SGA birth was reduced in multivitamin users regardless of their prepregnancy BMI (HR: 0.83; 95% CI: 0.73, 0.95), with the strongest association in regular users in the postconception period. Conclusion: Regular periconceptional multivitamin use was associated with reduced risk of SGA births and PTBs in nonoverweight women. PMID:21795441

Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort.

PubMed

Catov, Janet M; Bodnar, Lisa M; Olsen, Jorn; Olsen, Sjurdur; Nohr, Ellen A

2011-09-01

The intake of periconceptional multivitamins may decrease the risk of preterm births (PTBs) or small-for-gestational-age (SGA) births. We related the timing and frequency of periconceptional multivitamin use to SGA births and PTBs and its clinical presentations (ie, preterm labor, premature rupture of membranes, and medical induction). Women in the Danish National Birth Cohort (n = 35,897) reported the number of weeks of multivitamin use during a 12-wk periconceptional period. Cox regression was used to estimate the relation between any multivitamin use and PTBs (<37 wk) or SGA births (birth weight adjusted for gestational age >2 SDs below the mean on the basis of fetal growth curves). The timing (preconception and postconception) and frequency of use were also analyzed. Regular users (4-6 wk) and partial users (1-3 wk) in each period were compared with nonusers. The association between periconceptional multivitamin use and PTBs varied according to prepregnancy overweight status (P-interaction = 0.07). Regular preconception and postconception multivitamin use in women with a prepregnancy BMI (in kg/m(2)) <25 was associated with reduced risks of a PTB (HR: 0.84; 95% CI: 0.73, 0.95) and preterm labor (HR: 0.80; 95% CI: 0.69, 0.94). No similar associations were shown for overweight women. The adjusted risk of an SGA birth was reduced in multivitamin users regardless of their prepregnancy BMI (HR: 0.83; 95% CI: 0.73, 0.95), with the strongest association in regular users in the postconception period. Regular periconceptional multivitamin use was associated with reduced risk of SGA births and PTBs in nonoverweight women.

Enrichment of clinically relevant organisms in spontaneous preterm delivered placenta and reagent contamination across all clinical groups in a large UK pregnancy cohort.

PubMed

Leon, Lydia J; Doyle, Ronan; Diez-Benavente, Ernest; Clark, Taane G; Klein, Nigel; Stanier, Philip; Moore, Gudrun E

2018-05-18

In this study differences in the placental microbiota of term and preterm deliveries from a large UK pregnancy cohort were studied using 16S targeted amplicon sequencing. The impact of contamination from DNA extraction, PCR reagents, as well as those from delivery itself were also examined. A total of 400 placental samples from 256 singleton pregnancies were analysed and differences investigated between spontaneous preterm, non-spontaneous preterm, and term delivered placenta. DNA from recently delivered placenta was extracted, and screening for bacterial DNA was carried out using targeted sequencing of the 16S rRNA gene on the Illumina MiSeq platform. Sequenced reads were analysed for presence of contaminating operational taxonomic units (OTUs) identified via sequencing of negative extraction and PCR blank samples. Differential abundance and between sample (beta) diversity metrics were then compared. A large proportion of the reads sequenced from the extracted placental samples mapped to OTUs that were also found in negative extractions. Striking differences in the composition of samples were also observed, according to whether the placenta was delivered abdominally or vaginally, providing strong circumstantial evidence for delivery contamination as an important contributor to observed microbial profiles. When OTU and genus level abundances were compared between the groups of interest, a number of organisms were enriched in the spontaneous preterm cohort, including organisms that have been previously associated with adverse pregnancy outcomes, specifically Mycoplasma spp., and Ureaplasma spp.. However, analyses of overall community structure did not reveal convincing evidence for the existence of a reproducible 'preterm placental microbiome'. IMPORTANCE Preterm birth is associated with both psychological and physical disabilities and is the leading cause of infant morbidity and mortality worldwide. Infection is known to be an important cause of spontaneous preterm birth, and recent research has implicated variation in the 'placental microbiome' with preterm birth risk. Consistent with previous studies, the abundance of certain clinically relevant species differed between spontaneous preterm and non-spontaneous preterm or term delivered placenta. These results support the view that a proportion of spontaneous preterm births have an intra-uterine infection component. However, an additional observation from this study was that a substantial proportion of reads sequenced were contaminating reads, rather than DNA from endogenous, clinically relevant species. This observation warrants caution in the interpretation of sequencing output from such low biomass samples as the placenta. Copyright © 2018 Leon et al.

Mothers with alcoholic liver disease and the risk for preterm and small-for-gestational-age birth.

PubMed

Stokkeland, Knut; Ebrahim, Fereshte; Hultcrantz, Rolf; Ekbom, Anders; Stephansson, Olof

2013-01-01

To study pregnancy outcome in women with alcoholic liver disease (ALD). Using the Swedish nation-wide Patient and Medical Birth Registers, we investigated risk of adverse pregnancy outcome in 720 women diagnosed with ALD before and 1720 diagnosed after birth and compared them with 24 460 population-based control births. Women with ALD diagnosed before or after birth were generally of higher age and body mass index, more likely to smoke cigarettes during pregnancy and to have a low socio-economic status compared with controls. Women diagnosed with ALD before birth had an increased risk of moderately and very preterm birth, adjusted odd ratio (OR) = 1.53 (95% confidence interval (CI): 1.37-1.72 and 1.15-2.06 95%), respectively. Infants of mothers with ALD before birth were more often small-for-gestational age, adjusted OR = 1.22 (95% CI: 1.05-1.43), and were at increased risk for low Apgar scores (<7) at 5 min, adjusted OR = 1.49 (95% CI: 1.15-1.92) compared with controls. Similar associations with slightly lower-risk estimates were found among women diagnosed with ALD after birth. ALD is associated with adverse-birth outcomes, highlighting the importance of screening women for alcohol dependence in antenatal care.

Reducing preterm birth by a statewide multifaceted program: an implementation study.

PubMed

Newnham, John P; White, Scott W; Meharry, Suzanne; Lee, Han-Shin; Pedretti, Michelle K; Arrese, Catherine A; Keelan, Jeffrey A; Kemp, Matthew W; Dickinson, Jan E; Doherty, Dorota A

2017-05-01

A comprehensive preterm birth prevention program was introduced in the state of Western Australia encompassing new clinical guidelines, an outreach program for health care practitioners, a public health program for women and their families based on print and social media, and a new clinic at the state's sole tertiary level perinatal center for referral of those pregnant women at highest risk. The initiative had the single aim of safely lowering the rate of preterm birth. The objective of the study was to evaluate the outcomes of the initiative on the rates of preterm birth both statewide and in the single tertiary level perinatal referral center. This was a prospective population-based cohort study of perinatal outcomes before and after 1 full year of implementation of the preterm birth prevention program. In the state overall, the rate of singleton preterm birth was reduced by 7.6% and was lower than in any of the preceding 6 years. This reduction amounted to 196 cases relative to the year before the introduction of the initiative and the effect extended from the 28-31 week gestational age group onward. Within the tertiary level center, the rate of preterm birth in 2015 was also significantly lower than in the preceding years. A comprehensive and multifaceted preterm birth prevention program aimed at both health care practitioners and the general public, operating within the environment of a government-funded universal health care system can significantly lower the rate of early birth. Further research is now required to increase the effect and to determine the relative contributions of each of the interventions. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

What causes racial disparities in very preterm birth? A biosocial perspective.

PubMed

Kramer, Michael R; Hogue, Carol R

2009-01-01

Very preterm birth (<32 weeks' gestation) occurs in approximately 2% of livebirths but is a leading cause of infant mortality and morbidity in the United States. African-American women have a 2-fold to 3-fold elevated risk compared with non-Hispanic white women for reasons that are incompletely understood. This paper reviews the evidence for the biologic and social patterning of very preterm birth, with attention to leading hypotheses regarding the etiology of the racial disparity. A systematic review of the literature in the MEDLINE, CINAHL, PsycInfo, and EMBASE indices was conducted. The literature to date suggests a complex, multifactorial causal framework for understanding racial disparities in very preterm birth, with maternal inflammatory, vascular, or neuroendocrine dysfunction as proximal pathways and maternal exposure to stress, racial differences in preconceptional health, and genetic, epigenetic, and gene-environment interactions as more distal mediators. Interpersonal and institutionalized racism are mechanisms that may drive racially patterned differences. Current literature is limited in that research on social determinants and biologic processes of prematurity has been generally disconnected. Improved etiologic understanding and the potential for effective intervention may come with better integration of these research approaches.

Gene expression profiling at birth characterizing the preterm infant with early onset infection.

PubMed

Hilgendorff, Anne; Windhorst, Anita; Klein, Manuel; Tchatalbachev, Svetlin; Windemuth-Kieselbach, Christine; Kreuder, Joachim; Heckmann, Matthias; Gkatzoflia, Anna; Ehrhardt, Harald; Mysliwietz, Josef; Maier, Michael; Izar, Benjamin; Billion, Andre; Gortner, Ludwig; Chakraborty, Trinad; Hossain, Hamid

2017-02-01

Early onset infection (EOI) in preterm infants <32 weeks gestational age (GA) is associated with a high mortality rate and the development of severe acute and long-term complications. The pathophysiology of EOI is not fully understood and clinical and laboratory signs of early onset infections in this patient cohort are often not conclusive. Thus, the aim of this study was to identify signatures characterizing preterm infants with EOI by using genome-wide gene expression (GWGE) analyses from umbilical arterial blood of preterm infants. This prospective cohort study was conducted in preterm infants <32 weeks GA. GWGE analyses using CodeLink human microarrays were performed from umbilical arterial blood of preterm infants with and without EOI. GWGE analyses revealed differential expression of 292 genes in preterm infants with EOI as compared to infants without EOI. Infants with EOI could be further differentiated into two subclasses and were distinguished by the magnitude of the expression of genes involved in both neutrophil and T cell activation. A hallmark activity for both subclasses of EOI was a common suppression of genes involved in natural killer (NK) cell function, which was independent from NK cell numbers. Significant results were recapitulated in an independent validation cohort. Gene expression profiling may enable early and more precise diagnosis of EOI in preterm infants. Gene expression (GE) profiling at birth characterizes preterm infants with EOI. GE analysis indicates dysregulation of NK cell activity. NK cell activity at birth may be a useful marker to improve early diagnosis of EOI.

Executive Function is Associated with Social Competence in Preschool-Aged Children Born Preterm or Full Term

PubMed Central

Alduncin, Nidia; Huffman, Lynne C.; Feldman, Heidi M.; Loe, Irene M.

2014-01-01

Background Executive function (EF), defined as higher-order cognitive processes used in planning and organizing actions and emotions, is often impaired in children born preterm. Few studies have assessed social competence, the processes and resources required to meet social demands and achieve social goals, in children born preterm. The relations between EF and social competence in preterm and full term preschoolers have not been well characterized. Aims To characterize social competence and assess the relationship between EF and social competence in preschool-aged children born preterm or full term. Study design Cross-sectional study. Subjects Study subjects had a history of preterm birth (≤ 34 weeks gestation) and birth weight < 2500 g (n = 70). Controls were born full term (≥ 37 weeks) (n = 79). Outcome measures Children completed a battery of EF tasks; a mean age-adjusted z-score for the battery was generated for each child. Parents rated child EF on one scale and child social competence on two standardized scales. Results Compared to full term children, preterm children showed a lower mean EF battery z-score, poorer parent-rated EF, and poorer scores on the two social competence scales. In hierarchical multiple regression models, EF battery z-score and parent-rated EF made independent contributions to both measures of social competence. Preterm birth explained additional variance for one measure of social competence. Conclusions Standard assessment of EF skills and social competence in young preschool children, including children born preterm, may identify at-risk children for long-term social difficulties and may also provide targets for intervention. PMID:24661446

Cost-effectiveness of screening and treatment for bacterial vaginosis in early pregnancy among women at low risk for preterm birth.

PubMed

Kekki, Minnamaija; Kurki, Tapio; Kotomäki, Teija; Sintonen, Harri; Paavonen, Jorma

2004-01-01

Bacterial vaginosis (BV) is an important risk factor for preterm birth. BV is detected in 10-30% of pregnant women and is often asymptomatic. Treatment of BV during pregnancy seems to reduce the risk of preterm delivery among high-risk women. We performed a cost-effectiveness analysis of screening and treatment for BV in early pregnancy among asymptomatic women at low risk for preterm delivery. A decision tree was built with two arms. For the screening (and treatment) arm the probabilities were derived from our earlier randomized trial on screening and treatment for BV, consisting of BV-positive women treated with intravaginal clindamycin cream or placebo and also of BV-negative pregnant women. The probabilities of outcomes among these women were collected from antenatal clinic records and hospital records, and for the no-screening arm mainly from the Finnish Perinatal Statistics. The outcomes considered were preterm delivery, mode of delivery, peripartum infections and postpartum complications. The unit costs associated with these outcomes were mainly based on disease-related groups (DRGs). No-screening was compared with two screening programs (one with clindamycin, the other with metronidazole treatment) and subjected to sensitivity analyses. There was no significant difference between screening and no-screening strategies in the costs and in the rate of preterm deliveries but the screening strategy produced significantly fewer peripartum infections and postpartum complications. Sensitivity analyses suggested that the screening strategy may become cost-saving if the rate of preterm deliveries exceeds 3%. Screening and treatment for BV in early pregnancy may not reduce costs compared to no-screening in a population at low risk for preterm birth but would produce, at the same cost, more health benefits in terms of fewer peripartum infections and postpartum complications. However, it may be cost-saving if the rate of preterm deliveries is higher than 3%.

Evaluation of plasma C-reactive protein levels in pregnant women with and without periodontal disease: A comparative study

PubMed Central

Sharma, Anupriya; Ramesh, Amitha; Thomas, Biju

2009-01-01

Background and Objectives: Circulating C-reactive protein (CRP) levels are a marker of systemic inflammation and are associated with periodontal disease, a chronic bacterial infection associated with elevation of proinflammatory cytokines and prostaglandins. CRP has been associated with adverse pregnancy outcomes, including preterm delivery, preeclampsia, and intrauterine growth restriction. Furthermore, periodontal disease has been associated with increased risk of preterm low birth weight, low birth weight, and preterm birth. The present study was conducted to assess plasma CRP levels in pregnant women with and without periodontal disease; to evaluate the effect of periodontal therapy on the incidence of preterm delivery; and to compare the incidence of preterm delivery in pregnant women with and without periodontal disease. Materials and Methods: A total of 90 pregnant women aged between 18-35 years with gestational age between 12-28 weeks were recruited and divided into three equal groups (control group, study group, treatment group) of 30 each. Blood samples were taken for estimation of C-reactive protein levels from all groups at 12-20 weeks of gestation, determined using ultrasensitive turbidimetric immunoassay (QUANTIA-CRP US). The treatment group comprised plaque control, scaling, and root planning and daily rinsing with 0.2% chlorhexidine mouth before 28 weeks of gestation. Results: The mean value of C-reactive protein levels in subjects with periodontal disease was higher compared to control group i.e., 1.20 ± 0.247 mg/dl and 1.22 ± 0.250 mg/dl, respectively, compared to 0.713 ± 0.139 mg/ dl (P = 0.001). The mean value of CRP levels before treatment was greater than the mean value after treatment i.e., 1.22 ± 0.25 compared to 0.84 ± 0.189 (P < 0.001). The incidence of preterm delivery (< 37 weeks) was 31.7% in the periodontal disease group (study group) compared to 8.3% in the control group (P = 0.001). The incidence of preterm delivery in the treatment group was 15.0% compared to 31.7% in the nontreatment group (study group). Conclusion: The findings from the study suggest that periodontal disease in pregnant women is associated with increased C- reactive protein levels in early pregnancy, incidence of preterm delivery is higher in pregnant women with periodontal disease compared to healthy controls, periodontal therapy during pregnancy reduces plasma CRP levels and there is decrease in incidence of preterm delivery after periodontal therapy. PMID:20379412

Magnetic Resonance Imaging and Developmental Outcome Following Preterm Birth: Review of Current Evidence

ERIC Educational Resources Information Center

Hart, Anthony R.; Whitby, Elspeth W.; Griffiths, Paul D.; Smith, Michael F.

2008-01-01

Preterm birth is associated with an increased risk of developmental difficulties. Magnetic resonance imaging (MRI) is increasingly being used to identify damage to the brain following preterm birth. It is hoped this information will aid prognostication and identify neonates who would benefit from early therapeutic intervention. Cystic…

Contributors to Excess Infant Mortality in the U.S. South

PubMed Central

Hirai, Ashley H.; Sappenfield, William M.; Kogan, Michael D.; Barfield, Wanda D.; Goodman, David A.; Ghandour, Reem M.; Lu, Michael C.

2015-01-01

Background Infant mortality rates (IMRs) are disproportionally high in the U.S. South; however, the proximate contributors that could inform regional action remain unclear. Purpose To quantify the components of excess infant mortality in the U.S. South by maternal race/ethnicity, underlying cause of death, and gestational age. Methods U.S. Period Linked Birth/Infant Death Data Files 2007–2009 (analyzed in 2013) were used to compare IMRs between the South (U.S. Public Health Regions IV and VI) and all other regions combined. Results Compared to other regions, there were 1.18 excess infant deaths per 1000 live births in the South, representing about 1600 excess infant deaths annually. New Mexico and Texas did not have elevated IMRs relative to other regions; excess death rates among other states ranged from 0.62 per 1000 in Kentucky to 3.82 per 1000 in Mississippi. Racial/ethnic compositional differences, generally the greater proportion of non-Hispanic black births in the South, explained 59% of the overall regional difference; the remainder was mostly explained by higher IMRs among non-Hispanic whites. The leading causes of excess Southern infant mortality were sudden unexpected infant death (SUID; 36%, range=12% in Florida to 90% in Kentucky) and preterm-related death (22%, range=−71% in Kentucky to 51% in North Carolina). Higher rates of preterm birth, predominantly <34 weeks, accounted for most of the preterm contribution. Conclusions To reduce excess Southern infant mortality, comprehensive strategies addressing SUID and preterm birth prevention for both non-Hispanic black and white births are needed, with state-level findings used to tailor state-specific efforts. PMID:24512860

Validity of pre and post-term birth rates based on the date of last menstrual period compared to early obstetric ultrasonography.

PubMed

Medeiros, Maria Nilza Lima; Cavalcante, Nádia Carenina Nunes; Mesquita, Fabrício José Alencar; Batista, Rosângela Lucena Fernandes; Simões, Vanda Maria Ferreira; Cavalli, Ricardo de Carvalho; Cardoso, Viviane Cunha; Bettiol, Heloisa; Barbieri, Marco Antonio; Silva, Antônio Augusto Moura da

2015-04-01

The aim of this study was to assess the validity of the last menstrual period (LMP) estimate in determining pre and post-term birth rates, in a prenatal cohort from two Brazilian cities, São Luís and Ribeirão Preto. Pregnant women with a single fetus and less than 20 weeks' gestation by obstetric ultrasonography who received prenatal care in 2010 and 2011 were included. The LMP was obtained on two occasions (at 22-25 weeks gestation and after birth). The sensitivity of LMP obtained prenatally to estimate the preterm birth rate was 65.6% in São Luís and 78.7% in Ribeirão Preto and the positive predictive value was 57.3% in São Luís and 73.3% in Ribeirão Preto. LMP errors in identifying preterm birth were lower in the more developed city, Ribeirão Preto. The sensitivity and positive predictive value of LMP for the estimate of the post-term birth rate was very low and tended to overestimate it. LMP can be used with some errors to identify the preterm birth rate when obstetric ultrasonography is not available, but is not suitable for predicting post-term birth.

All Our Babies Cohort Study: recruitment of a cohort to predict women at risk of preterm birth through the examination of gene expression profiles and the environment

PubMed Central

2010-01-01

Background Preterm birth is the leading cause of perinatal morbidity and mortality. Risk factors for preterm birth include a personal or familial history of preterm delivery, ethnicity and low socioeconomic status yet the ability to predict preterm delivery before the onset of preterm labour evades clinical practice. Evidence suggests that genetics may play a role in the multi-factorial pathophysiology of preterm birth. The All Our Babies Study is an on-going community based longitudinal cohort study that was designed to establish a cohort of women to investigate how a women's genetics and environment contribute to the pathophysiology of preterm birth. Specifically this study will examine the predictive potential of maternal leukocytes for predicting preterm birth in non-labouring women through the examination of gene expression profiles and gene-environment interactions. Methods/Design Collaborations have been established between clinical lab services, the provincial health service provider and researchers to create an interdisciplinary study design for the All Our Babies Study. A birth cohort of 2000 women has been established to address this research question. Women provide informed consent for blood sample collection, linkage to medical records and complete questionnaires related to prenatal health, service utilization, social support, emotional and physical health, demographics, and breast and infant feeding. Maternal blood samples are collected in PAXgene™ RNA tubes between 18-22 and 28-32 weeks gestation for transcriptomic analyses. Discussion The All Our Babies Study is an example of how investment in clinical-academic-community partnerships can improve research efficiency and accelerate the recruitment and data collection phases of a study. Establishing these partnerships during the study design phase and maintaining these relationships through the duration of the study provides the unique opportunity to investigate the multi-causal factors of preterm birth. The overall All Our Babies Study results can potentially lead to healthier pregnancies, mothers, infants and children. PMID:21192811

Application of a global reference for fetal-weight and birthweight percentiles in predicting infant mortality.

PubMed

Ding, G; Tian, Y; Zhang, Y; Pang, Y; Zhang, J S; Zhang, J

2013-12-01

To determine whether the recently published A global reference for fetal-weight and birthweight percentiles (Global Reference) improves small- (SGA), appropriate- (AGA), and large-for-gestational-age (LGA) definitions in predicting infant mortality. Population-based cohort study. The US Linked Livebirth and Infant Death records between 1995 and 2004. Singleton births with birthweight >500 g born at 24-41 weeks of gestation. We compared infant mortality rates of SGA, AGA, and LGA infants classified by three different references: the Global Reference; a commonly used birthweight reference; and Hadlock's ultrasound reference. Infant mortality rates. Among 33 997 719 eligible liveborn singleton births, 25% of preterm and 9% of term infants were classified differently for SGA, AGA, and LGA by the Global Reference and the birthweight reference. The Global Reference indicated higher mortality rates in preterm SGA and preterm LGA infants than the birthweight reference. The mortality rate was considerably higher in infants classified as preterm SGA by the Global Reference but not by the birthweight reference, compared with the corresponding infants classified by the birthweight reference but not by the Global Reference (105.7 versus 12.9 per 1000, RR 8.17, 95% CI 7.38-9.06). Yet, the differences in mortality rates were much smaller in term infants than in preterm infants. Black infants had a particularly higher mortality rate than other races in AGA and LGA preterm and term infants. In respect to the commonly used birthweight reference, the Global Reference increases the identification of infant deaths by improved classification of abnormal newborn size at birth, and these advantages were more obvious in preterm than in term infants. © 2013 RCOG.

A Potential Novel Spontaneous Preterm Birth Gene, AR, Identified by Linkage and Association Analysis of X Chromosomal Markers

PubMed Central

Karjalainen, Minna K.; Huusko, Johanna M.; Ulvila, Johanna; Sotkasiira, Jenni; Luukkonen, Aino; Teramo, Kari; Plunkett, Jevon; Anttila, Verneri; Palotie, Aarno; Haataja, Ritva; Muglia, Louis J.; Hallman, Mikko

2012-01-01

Preterm birth is the major cause of neonatal mortality and morbidity. In many cases, it has severe life-long consequences for the health and neurological development of the newborn child. More than 50% of all preterm births are spontaneous, and currently there is no effective prevention. Several studies suggest that genetic factors play a role in spontaneous preterm birth (SPTB). However, its genetic background is insufficiently characterized. The aim of the present study was to perform a linkage analysis of X chromosomal markers in SPTB in large northern Finnish families with recurrent SPTBs. We found a significant linkage signal (HLOD  = 3.72) on chromosome locus Xq13.1 when the studied phenotype was being born preterm. There were no significant linkage signals when the studied phenotype was giving preterm deliveries. Two functional candidate genes, those encoding the androgen receptor (AR) and the interleukin-2 receptor gamma subunit (IL2RG), located near this locus were analyzed as candidates for SPTB in subsequent case-control association analyses. Nine single-nucleotide polymorphisms (SNPs) within these genes and an AR exon-1 CAG repeat, which was previously demonstrated to be functionally significant, were analyzed in mothers with preterm delivery (n = 272) and their offspring (n = 269), and in mothers with exclusively term deliveries (n = 201) and their offspring (n = 199), all originating from northern Finland. A replication study population consisting of individuals born preterm (n = 111) and term (n = 197) from southern Finland was also analyzed. Long AR CAG repeats (≥26) were overrepresented and short repeats (≤19) underrepresented in individuals born preterm compared to those born at term. Thus, our linkage and association results emphasize the role of the fetal genome in genetic predisposition to SPTB and implicate AR as a potential novel fetal susceptibility gene for SPTB. PMID:23227263

Placental Alpha Microglobulin-1 Compared With Fetal Fibronectin to Predict Preterm Delivery in Symptomatic Women.

PubMed

Wing, Deborah A; Haeri, Sina; Silber, Angela C; Roth, Cheryl K; Weiner, Carl P; Echebiri, Nelson C; Franco, Albert; Pappas, Lanissa M; Yeast, John D; Brebnor, Angelle A; Quirk, J Gerald; Murphy, Aisling M; Laurent, Louise C; Field, Nancy T; Norton, Mary E

2017-12-01

To compare the rapid bedside test for placental α microglobulin-1 with the instrumented fetal fibronectin test for prediction of imminent spontaneous preterm delivery among women with symptoms of preterm labor. We conducted a prospective observational study on pregnant women with signs or symptoms suggestive of preterm labor between 24 and 35 weeks of gestation with intact membranes and cervical dilatation less than 3 cm. Participants were prospectively enrolled at 15 U.S. academic and community centers. Placental α microglobulin-1 samples did not require a speculum examination. Health care providers were blinded to placental α microglobulin-1 results. Fetal fibronectin samples were collected through speculum examination per manufacturer requirements and sent to a certified laboratory for testing using a cutoff of 50 ng/mL. The coprimary endpoints were positive predictive value (PPV) superiority and negative predictive value (NPV) noninferiority of placental α microglobulin-1 compared with fetal fibronectin for the prediction of spontaneous preterm birth within 7 days and within 14 days. Of 796 women included in the study cohort, 711 (89.3%) had both placental α microglobulin-1 and fetal fibronectin results and valid delivery outcomes available for analysis. The overall rate of preterm birth was 2.4% (17/711) within 7 days of testing and 4.2% (30/711) within 14 days of testing with respective rates of spontaneous preterm birth of 1.3% (9/703) and 2.9% (20/701). Fetal fibronectin was detected in 15.5% (110/711), and placental α microglobulin-1 was detected in 2.4% (17/711). The PPVs for spontaneous preterm delivery within 7 days or less among singleton gestations (n=13) for placental α microglobulin-1 and fetal fibronectin were 23.1% (3/13) and 4.3% (4/94), respectively (P<.025 for superiority). The NPVs were 99.5% (619/622) and 99.6% (539/541) for placental α microglobulin-1 and fetal fibronectin, respectively (P<.001 for noninferiority). Although placental α microglobulin-1 performed the same as fetal fibronectin in ruling out spontaneous preterm delivery among symptomatic women, it demonstrated statistical superiority in predicting it.

Pregnancy outcome after TNF-α inhibitor therapy during the first trimester: a prospective multicentre cohort study

PubMed Central

Weber-Schoendorfer, Corinna; Oppermann, Marc; Wacker, Evelin; Bernard, Nathalie; Beghin, Delphine; Cuppers-Maarschalkerweerd, Benedikte; Richardson, Jonathan L; Rothuizen, Laura E; Pistelli, Alessandra; Malm, Heli; Eleftheriou, Georgios; Kennedy, Debra; Kadioglu Duman, Mine; Meister, Reinhard; Schaefer, Christof

2015-01-01

Aims TNF-α inhibitors are considered relatively safe in pregnancy but experience is still limited. The aim of this study was to evaluate the risk of major birth defects, spontaneous abortion, preterm birth and reduced birth weight after first trimester exposure to TNF-α inhibitors. Methods Pregnancy outcomes of women on adalimumab, infliximab, etanercept, certolizumab pegol or golimumab were evaluated in a prospective observational cohort study and compared with outcomes of a non-exposed random sample. The samples were drawn from pregnancies identified by institutes collaborating in the European Network of Teratology Information Services. Results In total, 495 exposed and 1532 comparison pregnancies were contributed from nine countries. The risk of major birth defects was increased in the exposed (5.0%) compared with the non-exposed group (1.5%; adjusted odds ratio (ORadj) 2.2, 95% CI 1.0, 4.8). The risk of preterm birth was increased (17.6%; ORadj 1.69, 95% CI 1.1, 2.5), but not the risk of spontaneous abortion (16.2%; adjusted hazard ratio [HRadj] 1.06, 95% CI 0.7, 1.7). Birth weights adjusted for gestational age and sex were significantly lower in the exposed group compared to the non-exposed cohort (P = 0.02). As a diseased comparison group was not possible to ascertain, the influence of disease and treatment on birth weight and preterm birth could not be differentiated. Conclusions TNF-α inhibitors may carry a risk of adverse pregnancy outcome of moderate clinical relevance. Considering the impact of insufficiently controlled autoimmune disease on the mother and the unborn child, TNF-α inhibitors may nevertheless be a treatment option in women with severe disease refractory to established immunomodulatory drugs. PMID:25808588

Early interactive behaviours in preterm infants and their mothers: influences of maternal depressive symptomatology and neonatal birth weight.

PubMed

Agostini, Francesca; Neri, Erica; Dellabartola, Sara; Biasini, Augusto; Monti, Fiorella

2014-02-01

The study evaluated the quality of preterm infant-mother interactions, considering severity of birth weight (ELBW and VLBW) and maternal depression, compared to full term babies. 69 preterm infants (29 ELBW and 40 VLBW) and 80 full-term (FT) infants and their mothers were recruited. At 3 months of corrected age, the quality of mother-infant interaction was evaluated through Global Rating Scales; moreover, infant level of development and maternal depression were assessed through Griffith Development Mental Scales and Edinburgh Postnatal Depression Scale. Results showed adequate sensitivity in preterm infants' mothers and higher involvement with their infants, compared to full term mothers, but ELBW ones exhibited an intrusive interactive pattern and a higher prevalence of depressive symptoms. The study underlined the relevance of paying special attention to both ELBW infants and their mothers, in order to support the parenting role and the co-construction of early interactions. Copyright © 2013 Elsevier Inc. All rights reserved.

Prevention of preterm delivery with vaginal progesterone in women with preterm labour (4P): randomised double-blind placebo-controlled trial.

PubMed

Martinez de Tejada, B; Karolinski, A; Ocampo, M C; Laterra, C; Hösli, I; Fernández, D; Surbek, D; Huespe, M; Drack, G; Bunader, A; Rouillier, S; López de Degani, G; Seidenstein, E; Prentl, E; Antón, J; Krähenmann, F; Nowacki, D; Poncelas, M; Nassif, J C; Papera, R; Tuma, C; Espoile, R; Tiberio, O; Breccia, G; Messina, A; Peker, B; Schinner, E; Mol, B W; Kanterewicz, L; Wainer, V; Boulvain, M; Othenin-Girard, V; Bertolino, M V; Irion, O

2015-01-01

To evaluate the effectiveness of 200 mg of daily vaginal natural progesterone to prevent preterm birth in women with preterm labour. Multicentre, randomised, double-blind, placebo-controlled trial. Twenty-nine centres in Switzerland and Argentina. A total of 385 women with preterm labour (24(0/7) to 33(6/7) weeks of gestation) treated with acute tocolysis. Participants were randomly allocated to either 200 mg daily of self-administered vaginal progesterone or placebo within 48 hours of starting acute tocolysis. Primary outcome was delivery before 37 weeks of gestation. Secondary outcomes were delivery before 32 and 34 weeks, adverse effects, duration of tocolysis, re-admissions for preterm labour, length of hospital stay, and neonatal morbidity and mortality. The study was ended prematurely based on results of the intermediate analysis. Preterm birth occurred in 42.5% of women in the progesterone group versus 35.5% in the placebo group (relative risk [RR] 1.2; 95% confidence interval [95% CI] 0.93-1.5). Delivery at <32 and <34 weeks did not differ between the two groups (12.9 versus 9.7%; [RR 1.3; 95% CI 0.7-2.5] and 19.7 versus 12.9% [RR 1.5; 95% CI 0.9-2.4], respectively). The duration of tocolysis, hospitalisation, and recurrence of preterm labour were comparable between groups. Neonatal morbidity occurred in 44 (22.8%) cases on progesterone versus 35 (18.8%) cases on placebo (RR: 1.2; 95% CI 0.82-1.8), whereas there were 4 (2%) neonatal deaths in each study group. There is no evidence that the daily administration of 200 mg vaginal progesterone decreases preterm birth or improves neonatal outcome in women with preterm labour. © 2014 Royal College of Obstetricians and Gynaecologists.

A cohort study found that white blood cell count and endocrine markers predicted preterm birth in symptomatic women.

PubMed

Campbell, M Karen; Challis, John R G; DaSilva, Orlando; Bocking, Alan D

2005-03-01

This cohort study investigated potential clinical and biochemical predictors of subsequent preterm birth in women presenting with threatened preterm labor. Subjects were 218 pregnant women admitted to hospital with a diagnosis of threatened preterm labor at 22-36 weeks gestation. Exclusion criteria were multiple pregnancy, fetal anomalies, diabetes mellitus, abruptio placenta, preeclampsia, intrauterine growth restriction, cervical dilatation > 4 cm, and clinical signs of infection. Analyses used logistic regression. The presence of ruptured membranes was the best predictor of birth within 48 hours. Other important predictors were maternal white blood cell count at 22-27 weeks gestation and maternal adrenocorticotropin and corticotropin-releasing hormone concentrations at 28-36 weeks gestation. Subclinical infection may be an important etiologic factor in preterm births of gestational age < 28 weeks. For those at > or = 28 weeks gestation, the findings support the etiologic role of activation of the fetal and/or maternal hypothalamic pituitary adrenal axis leading to preterm birth.

Basic Information Processing Abilities at 11 years Account for Deficits in IQ Associated with Preterm Birth.

PubMed

Rose, Susan A; Feldman, Judith F; Jankowski, Jeffery J; Van Rossem, Ronan

2011-07-01

Although it is well established that preterms as a group do poorly relative to their full-term peers on tests of global cognitive functioning, the basis for this relative deficiency is less understood. The present paper examines preterm deficits in core cognitive abilities and determines their role in mediating preterm/full-term differences in IQ. The performance of 11-year-old children born preterm (birth weight <1750g) and their full-term controls were compared on a large battery of 15 tasks, covering four basic cognitive domains -- memory, attention, speed of processing and representational competence. The validity of these four domains was established using latent variables and confirmatory factor analysis (CFA). Preterms showed pervasive deficits within and across domains. Additionally, preterm deficits in IQ were completely mediated by these four cognitive domains in a structural equation model involving a cascade from elementary abilities (attention and speed), to more complex abilities (memory and representational competence), to IQ. The similarity of findings to those obtained with this cohort in infancy and toddlerhood suggest that preterm deficits persist - across time, across task, and from the non-verbal to the verbal period.

Basic Information Processing Abilities at 11 years Account for Deficits in IQ Associated with Preterm Birth

PubMed Central

Rose, Susan A.; Feldman, Judith F.; Jankowski, Jeffery J.; Van Rossem, Ronan

2011-01-01

Although it is well established that preterms as a group do poorly relative to their full-term peers on tests of global cognitive functioning, the basis for this relative deficiency is less understood. The present paper examines preterm deficits in core cognitive abilities and determines their role in mediating preterm/full-term differences in IQ. The performance of 11-year-old children born preterm (birth weight <1750g) and their full-term controls were compared on a large battery of 15 tasks, covering four basic cognitive domains -- memory, attention, speed of processing and representational competence. The validity of these four domains was established using latent variables and confirmatory factor analysis (CFA). Preterms showed pervasive deficits within and across domains. Additionally, preterm deficits in IQ were completely mediated by these four cognitive domains in a structural equation model involving a cascade from elementary abilities (attention and speed), to more complex abilities (memory and representational competence), to IQ. The similarity of findings to those obtained with this cohort in infancy and toddlerhood suggest that preterm deficits persist – across time, across task, and from the non-verbal to the verbal period. PMID:21643482

Racial residential segregation and preterm birth: built environment as a mediator.

PubMed

Anthopolos, Rebecca; Kaufman, Jay S; Messer, Lynne C; Miranda, Marie Lynn

2014-05-01

Racial residential segregation has been associated with preterm birth. Few studies have examined mediating pathways, in part because, with binary outcomes, indirect effects estimated from multiplicative models generally lack causal interpretation. We develop a method to estimate additive-scale natural direct and indirect effects from logistic regression. We then evaluate whether segregation operates through poor-quality built environment to affect preterm birth. To estimate natural direct and indirect effects, we derive risk differences from logistic regression coefficients. Birth records (2000-2008) for Durham, North Carolina, were linked to neighborhood-level measures of racial isolation and a composite construct of poor-quality built environment. We decomposed the total effect of racial isolation on preterm birth into direct and indirect effects. The adjusted total effect of an interquartile increase in racial isolation on preterm birth was an extra 27 preterm events per 1000 births (risk difference = 0.027 [95% confidence interval = 0.007 to 0.047]). With poor-quality built environment held at the level it would take under isolation at the 25th percentile, the direct effect of an interquartile increase in isolation was 0.022 (-0.001 to 0.042). Poor-quality built environment accounted for 35% (11% to 65%) of the total effect. Our methodology facilitates the estimation of additive-scale natural effects with binary outcomes. In this study, the total effect of racial segregation on preterm birth was partially mediated by poor-quality built environment.

The Effect of Cotrimoxazole Prophylactic Treatment on Malaria, Birth Outcomes, and Postpartum CD4 Count in HIV-Infected Women

PubMed Central

Dow, Anna; Hudgens, Michael G.; Van Rie, Annelies; King, Caroline C.; Ellington, Sascha; Chome, Nelecy; Turner, Abigail Norris; Kacheche, Zebrone; Jamieson, Denise J.; Chasela, Charles; van der Horst, Charles

2013-01-01

Background. Limited data exist on cotrimoxazole prophylactic treatment (CPT) in pregnant women, including protection against malaria versus standard intermittent preventive therapy with sulfadoxine-pyrimethamine (IPTp). Methods. Using observational data we examined the effect of CPT in HIV-infected pregnant women on malaria during pregnancy, low birth weight and preterm birth using proportional hazards, logistic, and log binomial regression, respectively. We used linear regression to assess effect of CPT on CD4 count. Results. Data from 468 CPT-exposed and 768 CPT-unexposed women were analyzed. CPT was associated with protection against malaria versus IPTp (hazard ratio: 0.35, 95% Confidence Interval (CI): 0.20, 0.60). After adjustment for time period this effect was not statistically significant (adjusted hazard ratio: 0.66, 95% CI: 0.28, 1.52). Among women receiving and not receiving CPT, rates of low birth weight (7.1% versus 7.6%) and preterm birth (23.5% versus 23.6%) were similar. CPT was associated with lower CD4 counts 24 weeks postpartum in women receiving (−77.6 cells/μL, 95% CI: −125.2, −30.1) and not receiving antiretrovirals (−33.7 cells/μL, 95% CI: −58.6, −8.8). Conclusions. Compared to IPTp, CPT provided comparable protection against malaria in HIV-infected pregnant women and against preterm birth or low birth weight. Possible implications of CPT-associated lower CD4 postpartum warrant further examination. PMID:24363547

Global, regional and national levels and trends of preterm birth rates for 1990 to 2014: protocol for development of World Health Organization estimates.

PubMed

Vogel, Joshua P; Chawanpaiboon, Saifon; Watananirun, Kanokwaroon; Lumbiganon, Pisake; Petzold, Max; Moller, Ann-Beth; Thinkhamrop, Jadsada; Laopaiboon, Malinee; Seuc, Armando H; Hogan, Daniel; Tunçalp, Ozge; Allanson, Emma; Betrán, Ana Pilar; Bonet, Mercedes; Oladapo, Olufemi T; Gülmezoglu, A Metin

2016-06-17

The official WHO estimates of preterm birth are an essential global resource for assessing the burden of preterm birth and developing public health programmes and policies. This protocol describes the methods that will be used to identify, critically appraise and analyse all eligible preterm birth data, in order to develop global, regional and national level estimates of levels and trends in preterm birth rates for the period 1990 - 2014. We will conduct a systematic review of civil registration and vital statistics (CRVS) data on preterm birth for all WHO Member States, via national Ministries of Health and Statistics Offices. For Member States with absent, limited or lower-quality CRVS data, a systematic review of surveys and/or research studies will be conducted. Modelling will be used to develop country, regional and global rates for 2014, with time trends for Member States where sufficient data are available. Member States will be invited to review the methodology and provide additional eligible data via a country consultation before final estimates are developed and disseminated. This research will be used to generate estimates on the burden of preterm birth globally for 1990 to 2014. We invite feedback on the methodology described, and call on the public health community to submit pertinent data for consideration. Registered at PROSPERO CRD42015027439 CONTACT: pretermbirth@who.int.

Validity of Newborn Clinical Assessment to Determine Gestational Age in Bangladesh

PubMed Central

Mullany, Luke C.; Ladhani, Karima; Uddin, Jamal; Mitra, Dipak; Ahmed, Parvez; Christian, Parul; Labrique, Alain; DasGupta, Sushil K.; Lokken, R. Peter; Quaiyum, Mohammed; Baqui, Abdullah H

2016-01-01

BACKGROUND: Gestational age (GA) is frequently unknown or inaccurate in pregnancies in low-income countries. Early identification of preterm infants may help link them to potentially life-saving interventions. METHODS: We conducted a validation study in a community-based birth cohort in rural Bangladesh. GA was determined by pregnancy ultrasound (<20 weeks). Community health workers conducted home visits (<72 hours) to assess physical/neuromuscular signs and measure anthropometrics. The distribution, agreement, and diagnostic accuracy of different clinical methods of GA assessment were determined compared with early ultrasound dating. RESULTS: In the live-born cohort (n = 1066), the mean ultrasound GA was 39.1 weeks (SD 2.0) and prevalence of preterm birth (<37 weeks) was 11.4%. Among assessed newborns (n = 710), the mean ultrasound GA was 39.3 weeks (SD 1.6) (8.3% preterm) and by Ballard scoring the mean GA was 38.9 weeks (SD 1.7) (12.9% preterm). The average bias of the Ballard was –0.4 weeks; however, 95% limits of agreement were wide (–4.7 to 4.0 weeks) and the accuracy for identifying preterm infants was low (sensitivity 16%, specificity 87%). Simplified methods for GA assessment had poor diagnostic accuracy for identifying preterm births (community health worker prematurity scorecard [sensitivity/specificity: 70%/27%]; Capurro [5%/96%]; Eregie [75%/58%]; Bhagwat [18%/87%], foot length <75 mm [64%/35%]; birth weight <2500 g [54%/82%]). Neonatal anthropometrics had poor to fair performance for classifying preterm infants (areas under the receiver operating curve 0.52–0.80). CONCLUSIONS: Newborn clinical assessment of GA is challenging at the community level in low-resource settings. Anthropometrics are also inaccurate surrogate markers for GA in settings with high rates of fetal growth restriction. PMID:27313070

Validity of Newborn Clinical Assessment to Determine Gestational Age in Bangladesh.

PubMed

Lee, Anne Cc; Mullany, Luke C; Ladhani, Karima; Uddin, Jamal; Mitra, Dipak; Ahmed, Parvez; Christian, Parul; Labrique, Alain; DasGupta, Sushil K; Lokken, R Peter; Quaiyum, Mohammed; Baqui, Abdullah H

2016-07-01

Gestational age (GA) is frequently unknown or inaccurate in pregnancies in low-income countries. Early identification of preterm infants may help link them to potentially life-saving interventions. We conducted a validation study in a community-based birth cohort in rural Bangladesh. GA was determined by pregnancy ultrasound (<20 weeks). Community health workers conducted home visits (<72 hours) to assess physical/neuromuscular signs and measure anthropometrics. The distribution, agreement, and diagnostic accuracy of different clinical methods of GA assessment were determined compared with early ultrasound dating. In the live-born cohort (n = 1066), the mean ultrasound GA was 39.1 weeks (SD 2.0) and prevalence of preterm birth (<37 weeks) was 11.4%. Among assessed newborns (n = 710), the mean ultrasound GA was 39.3 weeks (SD 1.6) (8.3% preterm) and by Ballard scoring the mean GA was 38.9 weeks (SD 1.7) (12.9% preterm). The average bias of the Ballard was -0.4 weeks; however, 95% limits of agreement were wide (-4.7 to 4.0 weeks) and the accuracy for identifying preterm infants was low (sensitivity 16%, specificity 87%). Simplified methods for GA assessment had poor diagnostic accuracy for identifying preterm births (community health worker prematurity scorecard [sensitivity/specificity: 70%/27%]; Capurro [5%/96%]; Eregie [75%/58%]; Bhagwat [18%/87%], foot length <75 mm [64%/35%]; birth weight <2500 g [54%/82%]). Neonatal anthropometrics had poor to fair performance for classifying preterm infants (areas under the receiver operating curve 0.52-0.80). Newborn clinical assessment of GA is challenging at the community level in low-resource settings. Anthropometrics are also inaccurate surrogate markers for GA in settings with high rates of fetal growth restriction. Copyright © 2016 by the American Academy of Pediatrics.

Preterm birth prevention in twin pregnancies with progesterone, pessary, or cerclage: a systematic review and meta-analysis.

PubMed

Jarde, A; Lutsiv, O; Park, C K; Barrett, J; Beyene, J; Saito, S; Dodd, J M; Shah, P S; Cook, J L; Biringer, A B; Giglia, L; Han, Z; Staub, K; Mundle, W; Vera, C; Sabatino, L; Liyanage, S K; McDonald, S D

2017-07-01

About half of twin pregnancies deliver preterm, and it is unclear whether any intervention reduces this risk. To assess the evidence for the effectiveness of progesterone, cerclage, and pessary in twin pregnancies. We searched Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, and ISI Web of Science, without language restrictions, up to 25 January 2016. Randomised controlled trials of progesterone, cerclage, or pessary for preventing preterm birth in women with twin pregnancies, without symptoms of threatened preterm labour. Two independent reviewers extracted data using a piloted form. Study quality was appraised with the Cochrane Risk of Bias tool. We performed pairwise inverse variance random-effects meta-analyses. We included 23 trials (all but three were considered to have a low risk of bias) comprising 6626 women with twin pregnancies. None of the interventions significantly reduced the risk of preterm birth overall at <34 or <37 weeks of gestation, or neonatal death, our primary outcomes, compared to a control group. In women receiving vaginal progesterone, the relative risk (RR) of preterm birth <34 weeks of gestation was 0.82 (95% CI 0.64-1.05, seven studies, I 2  36%), with a significant reduction in some key secondary outcomes, including very low birthweight (<1500 g, RR 0.71, 95% CI 0.52-0.98, four studies, I 2  46%) and mechanical ventilation (RR 0.61, 95% CI 0.45-0.82, four studies, I 2  22%). In twin gestations, although no overarching intervention was beneficial for the prevention of preterm birth and its sequelae, vaginal progesterone improved some important secondary outcomes. Vaginal progesterone may be beneficial in twin pregnancies, but not 17-OHPC, cerclage, or pessary. © 2017 Royal College of Obstetricians and Gynaecologists.

Birth-Weight, Pregnancy Term, Pre-Natal and Natal Complications Related to Child's Dental Anomalies.

PubMed

Prokocimer, T; Amir, E; Blumer, S; Peretz, B

2015-01-01

This cross-sectional study was aimed at determining whether certain pre-natal and natal conditions can predict specific dental anomalies. The conditions observed were: low birth-weight, preterm birth, pre-natal & natal complications. The dental anomalies observed were: enamel defects, total number of decayed, missing and filled teeth (total DMFT), disturbances in the tooth shape and disturbances in the number of teeth. Out of more than 2000 medical files of children aged 2-17 years old which were reviewed, 300 files met the selection criteria. Information recorded from the files included: age, gender, health status (the ASA physical status classification system by the American Society of Anesthesiologists), birth week, birth weight, total DMFT, hypomineralization, abnormal tooth shape, abnormal number of teeth and hypoplasia. Twenty one children out of 300 (7%) were born after a high-risk pregnancy, 25 children (8.3%) were born after high-risk birth, 20 children (6.7%) were born preterm - before week 37, and 29 children (9.7%) were born with a low birth weight (LBW) - 2500 grams or less. A relationship between a preterm birth and LBW to hypomineralization was found. And a relationship between a preterm birth and high-risk pregnancy to abnormal number of teeth was found. No relationship was found between birth (normal/high-risk) and the other parameters inspected. Preterm birth and LBW may predict hypomineralization in both primary and permanent dentitions. Furthermore, the study demonstrated that preterm birth and high-risk pregnancy may predict abnormal number of teeth in both dentitions.

Ethanol for preventing preterm birth in threatened preterm labor.

PubMed

Haas, David M; Morgan, Amanda M; Deans, Samantha J; Schubert, Frank P

2015-11-05

Preterm birth is the leading cause of death and disability in newborns worldwide. A wide variety of tocolytic agents have been utilized to delay birth for women in preterm labor. One of the earliest tocolytics utilized for this purpose was ethanol infusion, although this is not generally used in current practice due to safety concerns for both the mother and her baby. To determine the efficacy of ethanol in stopping preterm labor, preventing preterm birth, and the impact of ethanol on neonatal outcomes. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 May 2015) and reference lists of retrieved studies. We included randomized and quasi-randomized studies. Cluster-randomized trials and cross-over design trials were not eligible for inclusion. We only included studies published in abstract form if there was enough information on methods and relevant outcomes. Trials were included if they compared ethanol infusion to stop preterm labor versus placebo/control or versus other tocolytic drugs. At least two review authors independently assessed studies for inclusion and risk of bias. At least two review authors independently extracted data. Data were checked for accuracy. Twelve trials involving 1586 women met inclusion criteria for this review. One trial did not report on the outcomes of interest in this review.Risk of bias of included studies: The included studies generally were of low quality based on inadequate reporting of methodology. Only three trials had low risk of bias for random sequence generation and one had low risk of bias for allocation concealment and participant blinding. Most studies were either high risk of bias or uncertain in these key areas. Comparison 1: Ethanol versus placebo/control (two trials, 77 women) Compared to controls receiving pain medications and dextrose solution, ethanol did not improve any of the primary outcomes: birth < 48 hours after trial entry (one trial, 35 women; risk ratio (RR) 0.93, 95% confidence interval (CI) 0.43 to 2.00), or neonatal mortality (one trial, 35 women; RR 1.06, 95% CI 0.31 to 3.58). Serious maternal adverse events and perinatal mortality were not reported by either of the two trials in this comparison. Maternal adverse events (overall) were not reported but one trial (42 women) reported that there were no maternal adverse events that required stopping or changing drug) in either group. One trial did report delay until delivery but this outcome was reported as a median with no mention of the standard deviation (median 19 days in ethanol group versus "less than 1" day in the glucose/water group). There were no differences in any secondary outcomes reported: preterm birth < 34 weeks or < 37 weeks; serious infant outcome; fetal alcohol syndrome/fetal alcohol spectrum disorder; or small-for-gestational age. Comparison 2: Ethanol versus other tocolytic (betamimetics) (nine trials, 1438 women) Compared to betamimetics (the only tocolytic used as a comparator in these studies), ethanol was associated with no clear difference in the rate of birth < 48 hours after trial entry (two trials, 130 women; average RR 1.12, 95% CI 0.53 to 2.37, Tau² = 0.19, I² = 59%), similar rates of perinatal mortality (six trials, 698 women; RR1.20, 95% CI 0.78 to 1.84), higher rates of neonatal mortality (eight trials, 1238 women; RR 1.43, 95% CI 1.02 to 2.02), higher rates of preterm birth < 34 weeks (two trials, 599 women; RR 1.56, 95% CI 1.11 to 2.19), higher rates of neonatal respiratory distress syndrome (three trials, 823 women; RR 1.76, 95% CI 1.33 to 2.33), and higher rates of low birthweight babies < 2500 g (five trials, 834 women; RR 1.30, 95% CI 1.09 to 1.54). These outcomes are likely all related to the lower incidence of preterm birth seen with other tocolytics, which for all these comparisons were betamimetics. Serious maternal adverse events were not reported in any of the nine trial reports. However, ethanol had a trend towards a lower rate of maternal adverse events requiring stopping or changing the drug (three trials, 214 women; RR 0.25, 95% CI 0.06 to 0.97). There were no differences in other secondary outcomes of preterm birth < 37 weeks, number of days delivery was delayed, or overall maternal adverse events.Planned sensitivity analysis, excluding quasi-randomized trials did not substantially change the results of the primary outcome analyses with the exception of neonatal mortality which no longer showed a clear difference between the ethanol and other tocolytic groups (3 trials, 330 women; RR 1.49, 95% CI 0.82 to 2.72). This review is based on evidence from twelve studies which were mostly low quality. There is no evidence that to suggest that ethanol is an effective tocolytic compared to placebo. There is some evidence that ethanol may be better tolerated than other tocolytics (in this case betamimetics), but this result is based on few studies and small sample size and therefore should be interpreted with caution. Ethanol appears to be inferior to betamimetics for preventing preterm birth in threatened preterm labor.Ethanol is generally no longer used in current practice due to safety concerns for the mother and her baby. There is no need for new studies to evaluate the use of ethanol for preventing preterm birth in threatened preterm labour. However, it would be useful for long-term follow-up studies on the babies born to mothers from the existing studies in order to assess the risk of long-term neurodevelopmental status.

No improvement in socioeconomic inequalities in birthweight and preterm birth over four decades: a population-based cohort study.

PubMed

Glinianaia, Svetlana V; Ghosh, Rakesh; Rankin, Judith; Pearce, Mark S; Parker, Louise; Pless-Mulloli, Tanja

2013-04-15

Birthweight and gestational age are associated with socioeconomic deprivation, but the evidence in relation to temporal changes in these associations is sparse. We investigated changes in the associations between socioeconomic status (SES) and birthweight and gestational age in Newcastle upon Tyne, North of England, during 1961-2000. We used population-based data from hospital neonatal records on all singleton births to mothers resident in Newcastle (births with complete covariate information n = 113,182). We used linear regression to analyse the associations between neighbourhood SES and birthweight over the entire 40-year period and by decade, and logistic regression for associations with low birthweight (LBW) and preterm birth, adjusting for potential confounders. There was a significant interaction between SES and decade of birth for birthweight (p = 0.028) and preterm birth (p < 0.001). Socioeconomic gradients were similar in each decade for birthweight outcomes, but for preterm birth, socioeconomic disparities were more evident in the later decades [for 1961-70, odds ratio (OR) was 1.1, 95% CI 0.9, 1.3, for the most deprived versus the least deprived quartile, while for 1991-2000, the corresponding OR was 1.5, 95% CI 1.3, 1.7]. In each decade, there was a significant decrease in birthweight adjusted for gestational age for the most deprived compared to the least deprived SES group [1961-1970: -113.4 g (95% CI-133.0, -93.8); 1991-2000: -97.5 g (95% CI-113.0, -82.0)], while there was a significant increase in birthweight in each SES group over time. Socioeconomic inequalities did not narrow over the four decades for birthweight and widened for preterm birth. Mean birthweight adjusted for gestational age increased in all socioeconomic groups, suggesting an overall increase in fetal growth.

Maternity leave duration and adverse pregnancy outcomes: An international country-level comparison.

PubMed

Kwegyir-Afful, Emma; Adu, George; Spelten, Evelien R; Räsänen, Kimmo; Verbeek, Jos

2017-12-01

Preterm birth and low birthweight (LBW) lead to infant morbidity and mortality. The causes are unknown. This study evaluates the association between duration of maternity leave and birth outcomes at country level. We compiled data on duration of maternity leave for 180 countries of which 36 specified prenatal leave, 190 specified income, 183 specified preterm birth rates and 185 specified the LBW rate. Multivariate and seemingly unrelated regression analyses were done in STATA. Mean maternity leave duration was 15.4 weeks ( SD=7.7; range 4-52 weeks). One additional week of maternity leave was associated with a 0.09% lower preterm rate (95% confidence interval [CI] -0.15 to -0.04) adjusting for income and being an African country. An additional week of maternity leave was associated with a 0.14% lower rate of LBW (95% CI -0.24 to -0.05). Mean prenatal maternity leave across 36 countries was six weeks ( SD=2.7; range 2-14 weeks). One week of prenatal maternity leave was associated with a 0.07% lower preterm rate (95% CI -0.10 to 0.24) and a 0.06% lower rate of LBW (95% CI -0.14 to 0.27), but these results were not statistically significant. By adjusting for income status categories, the preterm birth rate was 1.53% higher and the LBW rate was 2.17% higher in Africa compared to the rest of the world. Maternity leave duration is significantly associated with birth outcomes. However, the association was not significant among 36 countries that specified prenatal maternity leave. Studies are needed to evaluate the correlation between prenatal leave and birth outcomes.

Unconditional Prenatal Income Supplement and Birth Outcomes.

PubMed

Brownell, Marni D; Chartier, Mariette J; Nickel, Nathan C; Chateau, Dan; Martens, Patricia J; Sarkar, Joykrishna; Burland, Elaine; Jutte, Douglas P; Taylor, Carole; Santos, Robert G; Katz, Alan

2016-06-01

Perinatal outcomes have improved in developed countries but remain poor for disadvantaged populations. We examined whether an unconditional income supplement to low-income pregnant women was associated with improved birth outcomes. This study included all mother-newborn pairs (2003-2010) in Manitoba, Canada, where the mother received prenatal social assistance, the infant was born in the hospital, and the pair had a risk screen (N = 14 591). Low-income women who received the income supplement (Healthy Baby Prenatal Benefit [HBPB], n = 10 738) were compared with low-income women who did not receive HBPB (n = 3853) on the following factors: low birth weight, preterm, small and large for gestational age, Apgar score, breastfeeding initiation, neonatal readmission, and newborn hospital length of stay (LOS). Covariates from risk screens were used to develop propensity scores and to balance differences between groups in regression models; γ sensitivity analyses were conducted to assess sensitivity to unmeasured confounding. Population-attributable and preventable fractions were calculated. HBPB was associated with reductions in low birth weight (aRR, 0.71 [95% CI, 0.63-0.81]), preterm births (aRR, 0.76 [95% CI, 0.69-0.84]) and small for gestational age births (aRR, 0.90 [95% CI, 0.81-0.99]) and increases in breastfeeding (aRR, 1.06 [95% CI, 1.03-1.09]) and large for gestational age births (aRR, 1.13 [95% CI, 1.05-1.23]). For vaginal births, HBPB was associated with shortened LOS (weighted mean, 2.86; P < .0001). Results for breastfeeding, low birth weight, preterm birth, and LOS were robust to unmeasured confounding. Reductions of 21% (95% CI, 13.6-28.3) for low birth weight births and 17.5% (95% CI, 11.2-23.8) for preterm births were associated with HBPB. Receipt of an unconditional prenatal income supplement was associated with positive outcomes. Placing conditions on income supplements may not be necessary to promote prenatal and perinatal health. Copyright © 2016 by the American Academy of Pediatrics.

[A follow-up on first-year growth and development of 61 very low birth weight preterm infants].

PubMed

Deng, Ying; Xiong, Fei; Wu, Meng-Meng; Yang, Fan

2016-06-01

To investigate the physical growth and psychomotor development of very low birth weight (VLBW) preterm infants in the first year after birth and related influencing factors. A total of 61 VLBW preterm infants received growth and development monitoring for 12 months. Z score was used to evaluate parameters for physical growth, and Denver Development Screen Test (DDST) was used for development screening. Among the 61 VLBW preterm infants, 27 (44.3%) were small-for-gestational-age (SGA) infants, and 34 (55.7%) were appropriate-for-gestational-age (AGA) infants. During the 1-year follow-up, the median weight-for-age Z-score (WAZ), height-for-age Z-score (HAZ), head circumference-for-age Z-score (HCZ), and weight-for-height Z score (WHZ) were >-1 SD in all age groups. The peaks of body mass index-for-age Z-score (BAZ) and WHZ appeared at 1 month of corrected age. At a corrected age of 40 weeks, the incidence rates of underweight, growth retardation, emaciation, microcephalus, overweight, and obesity were 15%, 16%, 11%, 13%, 20%, and 10%, respectively. Compared with those with a corrected age of 40 weeks, the infants with a corrected age of 6 months or 9-12 months had a significantly reduced incidence rate of overweight (3%) (P<0.05). Up to 1 year after birth, 15 infants (25%) had abnormal developmental quotient (DQ). The SGA group had a significantly higher incidence rate of abnormal DQ than the AGA group (P<0.05). SGA was the independent risk factor for retarded growth in the first year after birth in VLBW preterm infants. VLBW preterm infants experience an obvious growth deviation within 3 months of corrected age. Within the first year after birth, the proportion of infants with abnormal DQ screened by DDST is high.

Impact of the Red River catastrophic flood on women giving birth in North Dakota, 1994-2000.

PubMed

Tong, Van T; Zotti, Marianne E; Hsia, Jason

2011-04-01

To document changes in birth rates, birth outcomes, and pregnancy risk factors among women giving birth after the 1997 Red River flood in North Dakota. We analyzed detailed county-level birth files pre-disaster (1994-1996) and post-disaster (1997-2000) in North Dakota. Crude birth rates and adjusted fertility rates were calculated. The demographic and pregnancy risk factors were described among women delivering singleton births. Logistic regression was conducted to examine associations between the disaster and low birth weight (<2,500 g), preterm birth (<37 weeks), and small for gestational age infants adjusting for confounders. The crude birth rate and direct-adjusted fertility rate decreased significantly after the disaster in North Dakota. The proportion of women giving birth who were older, non-white, unmarried, and had a higher education increased. Compared to pre-disaster, there were significant increases in the following maternal measures after the disaster: any medical risks (5.1-7.1%), anemia (0.7-1.1%), acute or chronic lung disease (0.4-0.5%), eclampsia (0.3-2.1%), and uterine bleeding (0.3-0.4%). In addition, there was a significant increase in births that were low birth weight (OR 1.11, 95% CI 1.03-1.21) and preterm (OR 1.09, 95% CI 1.03-1.16) after adjusting for maternal characteristics and smoking. Following the flood, there was an increase in medical risks, low birth weight, and preterm delivery among women giving birth in North Dakota. Further research that examines birth outcomes of women following a catastrophic disaster is warranted.

Perceptions and experiences of community members on caring for preterm newborns in rural Mangochi, Malawi: a qualitative study.

PubMed

Gondwe, Austrida; Munthali, Alister C; Ashorn, Per; Ashorn, Ulla

2014-12-02

The number of preterm birth is increasing worldwide, especially in low income countries. Malawi has the highest incidence of preterm birth in the world, currently estimated at 18.1 percent. The aim of this study was to explore the perceived causes of preterm birth, care practices for preterm newborn babies and challenges associated with preterm birth among community members in Mangochi District, southern Malawi. We conducted 14 focus group discussions with the following groups of participants: mothers (n = 4), fathers (n = 6) and grandmothers (n = 4) for 110 participants. We conducted 20 IDIs with mothers to preterm newborns (n = 10), TBAs (n = 6) and traditional healers (n = 4). A discussion guide was used to facilitate the focus group and in-depth interview sessions. Data collection took place between October 2012 and January 2013. We used content analysis to analyze data. Participants mentioned a number of perceptions of preterm birth and these included young and old maternal age, heredity, sexual impurity and maternal illness during pregnancy. Provision of warmth was the most commonly reported component of care for preterm newborns. Participants reported several challenges to caring for preterm newborns such as lack of knowledge on how to provide care, poverty, and the high time burden of care leading to neglect of household, farming and business duties. Women had the main responsibility for caring for preterm newborns. In this community, the reported poor care practices for preterm newborns were associated with poverty and lack of knowledge of how to properly care for these babies at home. Action is needed to address the current care practices for preterm babies among the community members.

Association of Antenatal Depression Symptoms and Antidepressant Treatment With Preterm Birth.

PubMed

Venkatesh, Kartik K; Riley, Laura; Castro, Victor M; Perlis, Roy H; Kaimal, Anjali J

2016-05-01

To evaluate the association of antenatal depression symptoms with preterm birth and small for gestational age (SGA). This was an observational cohort study conducted among women who completed Edinburgh Postnatal Depression Scale screening and delivered at 20 weeks of gestation or greater. The primary outcomes were preterm birth and an SGA neonate at birth (less than 10th percentile for gestational age); the primary predictor was an Edinburgh Postnatal Depression Scale antepartum score of 10 or greater, indicating symptoms of depression. Logistic regression models were used with and without consideration of antidepressant exposure during pregnancy. Among 7,267 women, 831 (11%) screened positive for depression. In multivariable analyses adjusting for maternal age, race, income, body mass index, tobacco use, lifetime diagnosis of major depression and anxiety, diabetes, hypertension, and preeclampsia, women who screened positive for depression experienced an increased risk of preterm birth (less than 37 weeks of gestation) (adjusted odds ratio [OR] 1.27, 95% confidence interval [CI] 1.04-1.55) and very preterm birth (less than 32 weeks of gestation) (adjusted OR 1.82, 95% CI 1.09-3.02) as well as of having an SGA neonate (adjusted OR 1.28, 95% CI 1.04-1.58). In secondary analyses, among women who were treated with an antidepressant during pregnancy (19% of those who screened positive and 5% of those who screened negative), depressive symptoms were not associated with a significantly increased risk of preterm and very preterm birth or an SGA neonate. In a large cohort of women screened for depression antepartum, those with depressive symptoms had an increased likelihood of preterm and very preterm delivery as well having an SGA neonate. Such risk was not apparent among women who were treated with an antidepressant medication.

Global report on preterm birth and stillbirth (6 of 7): ethical considerations

PubMed Central

2010-01-01

Introduction Despite the substantial global burden of preterm and stillbirth, little attention has been given to the ethical considerations related to research and interventions in the global context. Ethical dilemmas surrounding reproductive decisions and the care of preterm newborns impact the delivery of interventions, and are not well understood in low-resource settings. Issues such as how to address the moral and cultural attitudes surrounding stillbirths, have cross-cutting implications for global visibility of the disease burden. This analysis identifies ethical issues impacting definitions, discovery, development, and delivery of effective interventions to decrease the global burden of preterm birth and stillbirth. Methods This review is based on a comprehensive literature review; an ethical analysis of other articles within this global report; and discussions with GAPPS's Scientific Advisory Council, team of international investigators, and a community of international experts on maternal, newborn, and child health and bioethics from the 2009 International Conference on Prematurity and Stillbirth. The literature review includes articles in PubMed, Academic Search Complete (EBSCO), and Philosopher's Index with a range of 1995-2008. Results Advancements in discovery science relating to preterm birth and stillbirth require careful consideration in the design and use of repositories containing maternal specimens and data. Equally important is the need to improve clinical translation from basic science research to delivery of interventions, and to ensure global needs inform discovery science agenda-setting. Ethical issues in the development of interventions include a need to balance immediate versus long-term impacts—such as caring for preterm newborns rather than preventing preterm births. The delivery of interventions must address: women's health disparities as determinants of preterm birth and stillbirth; improving measurements of impact on equity in coverage; balancing maternal and newborn outcomes in choosing interventions; and understanding the personal and cross-cultural experiences of preterm birth and stillbirth among women, families and communities. Conclusion Efforts to improve visibility, funding, research and the successful delivery of interventions for preterm birth and stillbirth face a number of ethical concerns. Thoughtful input from those in health policy, bioethics and international research ethics helped shape an interdisciplinary global action agenda to prevent preterm birth and stillbirth. PMID:20233387

Relationship between periodontal disease and preterm low birth weight: systematic review.

PubMed

Teshome, Amare; Yitayeh, Asmare

2016-01-01

Periodontal disease is a neglected bacterial infection that causes destruction of the periodontium in pregnant women. Yet its impact on the occurrence of adverse pregnancy outcomes has not systematically evaluated and there is no clear statement on the relationship between periodontal disease and preterm low birth weight. The objective of this study was to summarize the evidence on the impact of periodontal disease on preterm low birth weight. We searched the following data bases from January 2005 to December 2015: CINAHL (cumulative index to nursing and allied health literature), MEDLINE, AMED, EMBASE (excerpta medica database), Cochrane library and Google scholar. Only case-control studies with full text in English were eligible. Critical appraisal of the identified articles was done by two authors independently to provide the possible relevance of the papers for inclusion in the review process. The selected Case control studies were critically appraised with 12 items structured checklist adapted from national institute of health (NIH). Odds ratio (OR) or risk ratios (RR) were extracted from the selected studies. The two reviewers who selected the appropriate studies also extracted the data and evaluated the risk of bias. Of 229 articles, ten studies with a total of 2423 participants with a mean age ranged from 13 to 49 years were met the inclusion criteria. The studies focused on preterm birth, low birth weight and /or preterm low birth weight and periodontitis. Of the selected studies, 9 implied an association between periodontal disease and increased risk of preterm birth, low birth weight and /or preterm low birth weight outcome (ORs ranging from 2.04 to 4.19) and only one study found no evidence of association. Periodontal disease may be one of the possible risk factor for preterm low birth weight infant. However, more precise studies with randomized clinical trial with sufficient follow-up period must be done to confirm the association.

Bacterial vaginosis in threatened preterm, preterm and term labour.

PubMed

Chawanpaiboon, Saifon; Pimol, Kanjana

2010-12-01

To present the prevalence of bacterial vaginosis in threatened preterm, preterm, and term labor and results after treatment. Forty-four, 50, and 56 pregnant women with threatened preterm, preterm, and term labor respectively were participated. Bacterial vaginosis was diagnosed by Amsel's criteria. Treatment by metronidazole or clindamycin was used. A case record form recorded maternal age, obstetric history, gestational age at admission and delivery, examination data, the route of delivery, and the newborn birth weight and conditions. The patients in threatened preterm labor group had significantly positive bacterial vaginosis when compared to those in the term labor group. Prevalence of bacterial vaginosis in threatened preterm, preterm, and term labor were presented The prevalence of bacterial vaginosis in both preterm labor groups was higher than in the term labor group.

A descriptive correlational study of bacterial vaginosis in pregnancy and its association with preterm birth: implications for advanced practice nurses.

PubMed

Mascagni, Jennifer R; Miller, Lucy H

2004-12-01

To expand on prior (often contradictory) research implicating maternal infection as a cause of preterm birth, specifically exploring whether bacterial vaginosis (BV) in pregnancy caused preterm birth in a sample of 103 women in a rural Mississippi obstetric-gynecologic clinic. This descriptive correlational study explored the relationship between BV and preterm birth, using retrospective chart data from a purposive sample of 103 women (for a power level of 95%) from one rural obstetric-gynecologic clinic. Contrary to the majority of published research, this study did not find a positive correlation between BV and preterm birth. This unexpected result raises questions, particularly given that the preponderance (86%) of women who tested positive for BV during their pregnancy were African American, a population in which both BV and preterm birth are more prevalent. Whether to screen for BV in pregnancy is a clinically important question not only in terms of the health of mother and child but also in terms of responsible use of resources. Clear findings supporting beneficial health results for screening would dictate screening regardless of the cost. But research continues to lack consensus on the efficacy of BV screening during pregnancy in preventing adverse pregnancy outcomes. In this study, as in some of the literature, the risk of preterm birth did not correlate positively with BV during pregnancy. In the absence of that correlation, cost gains importance. Nurse practitioners (NPs) must use resources wisely, including time, laboratory tests, and medications. Although some specialists recommend screening or treating all pregnant patients for BV, the current practice of not screening or treating all pregnant patients seems warranted until definitive findings establish a conclusive correlation between BV and preterm birth.

The Microbiome, Parturition, and Timing of Birth: More questions than answers

PubMed Central

Prince, Amanda L.; Antony, Kathleen M.; Chu, Derrick M.; Aagaard, Kjersti M.

2014-01-01

The causes of preterm birth are multifactorial, but its association with infection has been well-established. The predominant paradigm describes an ascending infection from the lower genital tract through the cervix and into the presumably sterile fetal membranes and placenta. Thus, an evaluation of the role of the vaginal microbiome in preterm birth is implicated. However, emerging fields of data described in this review suggest that the placenta might not be sterile, even in the absence of clinical infection. We thus propose an additional mechanism for placental colonization and infection: hematogenous spread. When considered in the context of decades of evidence demonstrating a strong risk of recurrence for preterm birth, studies on parturition are ideal for applying the rapidly expanding field of metagenomics and analytic pipelines. The translational implications toward identification of innovative treatments for the prevention of preterm birth are further discussed. In sum, exciting advances in understanding the role of both host and microbiota in parturition and preterm birth are on the horizon. PMID:24793619

Predicting Live Birth, Preterm Delivery, and Low Birth Weight in Infants Born from In Vitro Fertilisation: A Prospective Study of 144,018 Treatment Cycles

PubMed Central

Nelson, Scott M.; Lawlor, Debbie A.

2011-01-01

Background The extent to which baseline couple characteristics affect the probability of live birth and adverse perinatal outcomes after assisted conception is unknown. Methods and Findings We utilised the Human Fertilisation and Embryology Authority database to examine the predictors of live birth in all in vitro fertilisation (IVF) cycles undertaken in the UK between 2003 and 2007 (n = 144,018). We examined the potential clinical utility of a validated model that pre-dated the introduction of intracytoplasmic sperm injection (ICSI) as compared to a novel model. For those treatment cycles that resulted in a live singleton birth (n = 24,226), we determined the associates of potential risk factors with preterm birth, low birth weight, and macrosomia. The overall rate of at least one live birth was 23.4 per 100 cycles (95% confidence interval [CI] 23.2–23.7). In multivariable models the odds of at least one live birth decreased with increasing maternal age, increasing duration of infertility, a greater number of previously unsuccessful IVF treatments, use of own oocytes, necessity for a second or third treatment cycle, or if it was not unexplained infertility. The association of own versus donor oocyte with reduced odds of live birth strengthened with increasing age of the mother. A previous IVF live birth increased the odds of future success (OR 1.58, 95% CI 1.46–1.71) more than that of a previous spontaneous live birth (OR 1.19, 95% CI 0.99–1.24); p-value for difference in estimate <0.001. Use of ICSI increased the odds of live birth, and male causes of infertility were associated with reduced odds of live birth only in couples who had not received ICSI. Prediction of live birth was feasible with moderate discrimination and excellent calibration; calibration was markedly improved in the novel compared to the established model. Preterm birth and low birth weight were increased if oocyte donation was required and ICSI was not used. Risk of macrosomia increased with advancing maternal age and a history of previous live births. Infertility due to cervical problems was associated with increased odds of all three outcomes—preterm birth, low birth weight, and macrosomia. Conclusions Pending external validation, our results show that couple- and treatment-specific factors can be used to provide infertile couples with an accurate assessment of whether they have low or high risk of a successful outcome following IVF. Please see later in the article for the Editors' Summary PMID:21245905

Investigation of maternal environmental exposures in association with self-reported preterm birth

PubMed Central

Patel, Chirag J; Yang, Ting; Hu, Zhongkai; Wen, Qiaojun; Sung, Joyce; El-Sayed, Yasser Y; Cohen, Harvey; Gould, Jeffrey; Stevenson, David K; Shaw, Gary M; Ling, Xuefeng Bruce; Butte, Atul J

2015-01-01

Identification of maternal environmental factors influencing preterm birth risks is important to understand the reasons for the increase in prematurity since 1990. Here, we utilized a health survey, the US National Health and Nutrition Examination Survey (NHANES) to search for personal environmental factors associated with preterm birth. 201 urine and blood markers of environmental factors, such as allergens, pollutants, and nutrients were assayed in mothers (range of N: 49 to 724) who answered questions about any children born preterm (delivery <37 weeks). We screened each of the 201 factors for association with any child born preterm adjusting by age, race/ethnicity, education, and household income. We attempted to verify the top finding, urinary bisphenol A, in an independent study of pregnant women attending Lucile Packard Children’s Hospital. We conclude that the association between maternal urinary levels of bisphenol A and preterm birth should be evaluated in a larger epidemiological investigation. PMID:24373932

Preterm labor: one syndrome, many causes.

PubMed

Romero, Roberto; Dey, Sudhansu K; Fisher, Susan J

2014-08-15

Preterm birth is associated with 5 to 18% of pregnancies and is a leading cause of infant morbidity and mortality. Spontaneous preterm labor, a syndrome caused by multiple pathologic processes, leads to 70% of preterm births. The prevention and the treatment of preterm labor have been long-standing challenges. We summarize the current understanding of the mechanisms of disease implicated in this condition and review advances relevant to intra-amniotic infection, decidual senescence, and breakdown of maternal-fetal tolerance. The success of progestogen treatment to prevent preterm birth in a subset of patients at risk is a cause for optimism. Solving the mystery of preterm labor, which compromises the health of future generations, is a formidable scientific challenge worthy of investment. Copyright © 2014, American Association for the Advancement of Science.

Delayed development of neural language organization in very preterm born children.

PubMed

Mürner-Lavanchy, Ines; Steinlin, Maja; Kiefer, Claus; Weisstanner, Christian; Ritter, Barbara Catherine; Perrig, Walter; Everts, Regula

2014-01-01

This study investigates neural language organization in very preterm born children compared to control children and examines the relationship between language organization, age, and language performance. Fifty-six preterms and 38 controls (7-12 y) completed a functional magnetic resonance imaging language task. Lateralization and signal change were computed for language-relevant brain regions. Younger preterms showed a bilateral language network whereas older preterms revealed left-sided language organization. No age-related differences in language organization were observed in controls. Results indicate that preterms maintain atypical bilateral language organization longer than term born controls. This might reflect a delay of neural language organization due to very premature birth.

Is international or Asian criteria-based body mass index associated with maternal anaemia, low birthweight, and preterm births among Thai population? An observational study.

PubMed

Liabsuetrakul, Tippawan

2011-06-01

An observational study was conducted in the four southernmost provinces of Thailand aiming at determining the effect of international or Asian criteria-based body mass index (BMI) in predicting maternal anaemia, low birthweight (LBW), and preterm births among pregnant Thai women and the change in haemoglobin (Hb) level during pregnancy. Maternal anaemia was defined as a haemoglobin (Hb) level of <11 g/dL. Anaemia was detected in 27.4% and 26.9% of 1192 pregnant women at their first prenatal visit and the third trimester respectively. The proportions of overweight and obese women according to the Asian criteria-based pre-pregnancy BMI were higher than the international criteria-based BMI (22.4% and 10.1% vs 15.5% and 3.4% respectively). No significant difference between pre-pregnancy BMI and pregnancy BMI at the first prenatal visit was demonstrated (mean +/- standard deviation = 21.8 +/- 4.0 vs. 22.8 +/- 4.1). Underweight women had a significantly higher prevalence of maternal anaemia, LBW, and preterm birth compared to women with normal weight. Overweight and obese women at pre-pregnancy by the Asian criteria-based BMI had a lower prevalence of anaemia. The Hb levels did not change significantly over time. In addition to BMI, maternal age, parity, and late prenatal visit were independently associated with maternal anaemia, low birthweight, and preterm birth. Underweight pregnant women classified by international or Asian criteria-based BMI increased the risk of maternal anaemia, low birthweight, and preterm birth.

Is International or Asian Criteria-based Body Mass Index Associated with Maternal Anaemia, Low Birthweight, and Preterm Births among Thai Population?—An Observational Study

PubMed Central

2011-01-01

An observational study was conducted in the four southernmost provinces of Thailand aiming at determining the effect of international or Asian criteria-based body mass index (BMI) in predicting maternal anaemia, low birthweight (LBW), and preterm births among pregnant Thai women and the change in haemoglobin (Hb) level during pregnancy. Maternal anaemia was defined as a haemoglobin (Hb) level of <11 g/dL. Anaemia was detected in 27.4% and 26.9% of 1,192 pregnant women at their first prenatal visit and the third trimester respectively. The proportions of overweight and obese women according to the Asian criteria-based pre-pregnancy BMI were higher than the international criteria-based BMI (22.4% and 10.1% vs 15.5% and 3.4% respectively). No significant difference between pre-pregnancy BMI and pregnancy BMI at the first prenatal visit was demonstrated (mean±standard deviation=21.8±4.0 vs 22.8±4.1). Underweight women had a significantly higher prevalence of maternal anaemia, LBW, and preterm birth compared to women with normal weight. Overweight and obese women at pre-pregnancy by the Asian criteria-based BMI had a lower prevalence of anaemia. The Hb levels did not change significantly over time. In addition to BMI, maternal age, parity, and late prenatal visit were independently associated with maternal anaemia, low birthweight, and preterm birth. Underweight pregnant women classified by international or Asian criteria-based BMI increased the risk of maternal anaemia, low birthweight, and preterm birth. PMID:21766557

The bias in current measures of gestational weight gain

PubMed Central

Hutcheon, Jennifer A; Bodnar, Lisa M; Joseph, KS; Abrams, Barbara; Simhan, Hyagriv N; Platt, Robert W

2014-01-01

Summary Conventional measures of gestational weight gain (GWG), such as average rate of weight gain, are likely correlated with gestational duration. Such correlation could introduce bias to epidemiologic studies of GWG and adverse perinatal outcomes because many perinatal outcomes are also correlated with gestational duration. This study aimed to quantify the extent to which currently-used GWG measures may bias the apparent relation between maternal weight gain and risk of preterm birth. For each woman in a provincial perinatal database registry (British Columbia, Canada, 2000–2009), a total GWG was simulated such that it was uncorrelated with risk of preterm birth. The simulation was based on serial antenatal GWG measurements from a sample of term pregnancies. Simulated GWGs were classified using 3 approaches: total weight gain (kg), average rate of weight gain (kg/week) or adequacy of gestational weight gain in relation to Institute of Medicine recommendations, and their association with preterm birth ≤ 32 weeks was explored using logistic regression. All measures of GWG induced an apparent association between GWG and preterm birth ≤32 weeks even when, by design, none existed. Odds ratios in the lowest fifths of each GWG measure compared with the middle fifths ranged from 4.4 [95% CI 3.6, 5.4] (total weight gain) to 1.6 [95% CI 1.3, 2.0] (Institute of Medicine adequacy ratio). Conventional measures of GWG introduce serious bias to the study of maternal weight gain and preterm birth. A new measure of GWG that is uncorrelated with gestational duration is needed. PMID:22324496

Racial Differences in DNA-Methylation of CpG Sites Within Preterm-Promoting Genes and Gene Variants.

PubMed

Salihu, H M; Das, R; Morton, L; Huang, H; Paothong, A; Wilson, R E; Aliyu, M H; Salemi, J L; Marty, P J

2016-08-01

Objective To evaluate the role DNA methylation may play in genes associated with preterm birth for higher rates of preterm births in African-American women. Methods Fetal cord blood samples from births collected at delivery and maternal demographic and medical information were used in a cross-sectional study to examine fetal DNA methylation of genes implicated in preterm birth among black and non-black infants. Allele-specific DNA methylation analysis was performed using a methylation bead array. Targeted maximum likelihood estimation was applied to examine the relationship between race and fetal DNA methylation of candidate preterm birth genes. Receiver-operating characteristic analyses were then conducted to validate the CpG site methylation marker within the two racial groups. Bootstrapping, a method of validation and replication, was employed. Results 42 CpG sites were screened within 20 candidate gene variants reported consistently in the literature as being associated with preterm birth. Of these, three CpG sites on TNFAIP8 and PON1 genes (corresponding to: cg23917399; cg07086380; and cg07404485, respectively) were significantly differentially methylated between black and non-black individuals. The three CpG sites showed lower methylation status among infants of black women. Bootstrapping validated and replicated results. Conclusion for Practice Our study identified significant differences in levels of methylation on specific genes between black and non-black individuals. Understanding the genetic/epigenetic mechanisms that lead to preterm birth may lead to enhanced prevention strategies to reduce morbidity and mortality by eventually providing a means to identify individuals with a genetic predisposition to preterm labor.

The clinical efficacy of oral tocolytic therapy.

PubMed

Rust, O A; Bofill, J A; Arriola, R M; Andrew, M E; Morrison, J C

1996-10-01

Our purpose was to determine whether maintenance oral tocolytic therapy after preterm labor stabilization decreases uterine activity, reduces the rate of recurrent preterm labor and subsequent preterm birth, or improves neonatal outcome. Women with documented idiopathic preterm labor stabilized with acute tocolytic therapy were randomized to three groups: placebo, terbutaline 5 mg, or magnesium chloride 128 mg, all given orally every 4 hours. Patients and providers were blinded to group assignment. All subjects were enrolled in a comprehensive system of preterm birth prevention that included preterm labor education, weekly clinic visits, home uterine contraction assessment, daily phone contact, and 24-hour perinatal nurse access. Of the 248 patients who were randomized, 39 were delivered before discharge and 4 were lost to follow-up, leaving 205 for final analysis: 68 placebo, 72 terbutaline, and 65 magnesium. The terbutaline group had significantly more side effects than the placebo group did. All groups had otherwise similar perinatal outcomes when confounding variables were controlled for. Overall, the three groups had a preterm birth rate < 37 weeks of 55.6% delivery, < 34 weeks of 15.6%, a 20.4% rate of newborn intensive care unit admission, and a mean neonatal length of stay of 6.3 days. Maintenance oral tocolytic therapy did not decrease uterine activity, reduce the rate of recurrent preterm labor or preterm birth, or improve perinatal outcome. Overall improvement in perinatal outcome may be achieved with a comprehensive program of preterm birth prevention without the use of maintenance oral tocolytic therapy.

[Prolonged hospitalization versus home management for women with arrested preterm labour: a before-after study].

PubMed

Salzmann, M; Gaucherand, P; Doret, M

2013-04-01

To compare gestational age at birth and incidence of preterm birth inferior to 37 weeks of gestation (WG) in single pregnancies with either prolonged hospitalization, or early home discharge after arrested preterm labour. Management of preterm labour was changed in our public academic hospital because no evidence of benefits for prolonged hospitalization was found and because adverse effects related to long-term hospitalization were described. In this retrospective before-after study, we compare the attitude A (December 2006 to April 2008), a prolonged hospitalization until 32 or 34WG, with new attitude B (May 2008 to February 2010), an early discharge home if the cervical exam was unchanged since admission. A total of 140 patients were included: 70 in each group. Initial hospitalization stay was significantly shorter in Group B (respectively, 5.4±5.4 days and 11.4±12.1 days; P<0.05). Preterm spontaneous delivery is 14 (20%) in group A and 21 (28.6%) in Group B (P>0.05). Gestational ages at birth were 33(5/7) and 33(0/7) WG in groups A and B, respectively (P>0.05). If we focus on patients who were discharged home in the two groups (women who did not deliver no matter the hospitalization length), the gestational age at birth (38(4/7) and 38WG; ns) and the prematurity rate inferior to 37WG (17.2% and 22.4%; ns) were statistically similar. This study suggests that shorter hospitalization does not decrease the delivery term, nor does it increase the premature delivery incidence. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Characteristics of antigravity spontaneous movements in preterm infants up to 3 months of corrected age.

PubMed

Miyagishima, Saori; Asaka, Tadayoshi; Kamatsuka, Kaori; Kozuka, Naoki; Kobayashi, Masaki; Igarashi, Risa; Hori, Tsukasa; Yoto, Yuko; Tsutsumi, Hiroyuki

2016-08-01

We investigated whether spontaneous antigravity limbs movements in very low birth weight preterm infants were insufficient compared to those in term infants. The relationship between the quality of general movements (GMs) and antigravity limbs movements was also examined. Preterm infants with very low birth weight without central nervous system disorders nor severe respiration disorders, and healthy term infants were recruited. The infants were set in a supine position. The distance between both hands and between both feet, and the height of both hands and feet from the floor were recorded at 1-3 corrected months for preterm infants, and at 1-3 months for term infants by a 3D motion capture system. The measurements were adjusted for body proportions. GMs in preterm and term infants were assessed similarly. Thirteen preterm and 15 term infants completed the study. In preterm infants, the distance between both hands and between both feet were longer, and the height of both hands and feet were lower than those in term infants in all measurements. In term infants, the height of both hands and feet increased as they developed, but no change was observed in preterm infants. In preterm infants with abnormal GMs, the distance between both hands was longer, and the height of both hands and feet was lower than that in those with normal GMs. There were no such differences between preterm infants with normal GMs and term infants with normal GMs. Antigravity limbs movements in preterm infants within the first 3 month of corrected age were insufficient compared with those in term infants. Furthermore, no improvement with development was observed in preterm infants. In addition, preterm infants with abnormal GMs showed worse antigravity limbs movements than preterm and term infants with normal GMs. The preterm infants with normal GMs could behave similar to the full term infants. Copyright © 2016 Elsevier Inc. All rights reserved.

Intellectual Disability in Children Aged Less than Seven Years Born Moderately and Late Preterm Compared with Very Preterm and Term-Born Children--A Nationwide Birth Cohort Study

ERIC Educational Resources Information Center

Hirvonen, M.; Ojala, R.; Korhonen, P.; Haataja, P.; Eriksson, K.; Rantanen, K.; Gissler, M.; Luukkaala, T.; Tammela, O.

2017-01-01

Background: Prematurity has been shown to be associated with an increased risk of intellectual disability (ID). Method: The aim was to establish whether the prevalence of ID, defined as significant limitations in both intellectual (intelligence quotient below 70) and adaptive functioning among moderately preterm (MP; 32[superscript + 0]-33…

Father's education: an independent marker of risk for preterm birth.

PubMed

Blumenshine, Philip M; Egerter, Susan A; Libet, Moreen L; Braveman, Paula A

2011-01-01

To explore the association between paternal education and preterm birth, taking into account maternal social and economic factors. We analyzed data from a population-based cross-sectional postpartum survey, linked with birth certificates, of women who gave birth in California from 1999 through 2005 (n = 21,712). Women whose infants' fathers had not completed college had significantly higher odds of preterm birth than women whose infants' fathers were college graduates, even after adjusting for maternal education and family income [OR (95% CI) = 1.26 (1.01-1.58)]. The effect of paternal education was greater among unmarried women than among married women. Paternal education may represent an important indicator of risk for preterm birth, reflecting social and/or economic factors not measured by maternal education or family income. Researchers and policy makers committed to understanding and reducing socioeconomic disparities in birth outcomes should consider paternal as well as maternal socioeconomic factors in their analyses and policy decisions.

1,25-Dihydroxyvitamin D Deficiency Is Associated With Preterm Birth in African American and Caucasian Women

PubMed Central

Menon, Ramkumar; Fortunato, Stephen J.; Brou, Lina; Lee, Jae-Eun; Al-Hendy, Ayman

2014-01-01

Vitamin (vit) D deficiency and preterm birth (PTB) are more prevalent among African American (AA) women compared to caucasian (Cau) women. Because vit D is important in regulating cell-mediated immune responses, vit D insufficiency or deficiency during pregnancy may enhance inflammation in pregnant women and increase the risk of PTB. In this study, circulatory levels of 25-hydroxy (OH) and 1,25-dihydroxy (OH)2 vit D were measured using chemiluminescence and radioimmunoassay techniques, respectively, in AA (n = 108) and Cau (n = 84) women who delivered at term and preterm. The results from this study suggest that the serum levels of the 25-(OH) vit D concentrations tend to decrease (P = .06) in the Cau women who delivered at preterm compared to those delivering at term. However, the 25-(OH) vit D levels in Cau and AA between term and preterm deliveries were not significantly different. The serum levels of 1,25-(OH)2 vit D were found to be significantly lower in AA women compared to Cau women (P < .02) at term, and in the Cau (P < .01) and AA (P < .04) women delivering at preterm compared to those delivering at term. One-way analysis of variance demonstrated that 1,25-(OH)2 vit D levels were significantly lower in participants delivering at preterm (<34 weeks and between 34 and 37 weeks) compared to those delivering at term (>37 weeks).These results suggest that low levels of serum 1,25-(OH)2 vit D are associated with PTB, and vit D can potentially be used as a novel diagnostic marker in the detection of PTB. PMID:23793474

Healthy late preterm infants and supplementary artificial milk feeds: effects on breast feeding and associated clinical parameters.

PubMed

Mattsson, Elisabet; Funkquist, Eva-Lotta; Wickström, Maria; Nyqvist, Kerstin H; Volgsten, Helena

2015-04-01

to compare the influence of supplementary artificial milk feeds on breast feeding and certain clinical parameters among healthy late preterm infants given regular supplementary artificial milk feeds versus being exclusively breast fed from birth. a comparative study using quantitative methods. Data were collected via a parental diary and medical records. parents of 77 late preterm infants (34 5/7-36 6/7 weeks), whose mothers intended to breast feed, completed a diary during the infants׳ hospital stay. infants who received regular supplementary artificial milk feeds experienced a longer delay before initiation of breast feeding, were breast fed less frequently and had longer hospital stays than infants exclusively breast fed from birth. Exclusively breast-fed infants had a greater weight loss than infants with regular artificial milk supplementation. A majority of the mothers (65%) with an infant prescribed artificial milk never expressed their milk and among the mothers who used a breast-pump, milk expression commenced late (10-84 hours after birth). At discharge, all infants were breast fed to some extent, 43% were exclusively breast fed. clinical practice and routines influence the initiation of breast feeding among late preterm infants and may act as barriers to the mothers׳ establishment of exclusive breast feeding. Copyright © 2015 Elsevier Ltd. All rights reserved.

Economic Conditions During Pregnancy and Adverse Birth Outcomes Among Singleton Live Births in the United States, 1990-2013.

PubMed

Margerison-Zilko, Claire E; Li, Yu; Luo, Zhehui

2017-11-15

We know little about the relationship between the macroeconomy and birth outcomes, in part due to the methodological challenge of distinguishing effects of economic conditions on fetal health from effects of economic conditions on selection into live birth. We examined associations between state-level unemployment rates in the first 2 trimesters of pregnancy and adverse birth outcomes, using natality data on singleton live births in the United States during 1990-2013. We used fixed-effect logistic regression models and accounted for selection by adjusting for state-level unemployment before conception and maternal characteristics associated with both selection and birth outcomes. We also tested whether associations between macroeconomic conditions and birth outcomes differed during and after (compared with before) the Great Recession (2007-2009). Each 1-percentage-point increase in the first-trimester unemployment rate was associated with a 5% increase in odds of preterm birth, while second-trimester unemployment was associated with a 3% decrease in preterm birth odds. During the Great Recession, however, first-trimester unemployment was associated with a 16% increase in odds of preterm birth. These findings increase our understanding of the effects of the Great Recession on health and add to growing literature suggesting that macro-level social and economic factors contribute to perinatal health. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Effect of oral administration of probiotics on intestinal colonization with drug-resistant bacteria in preterm infants].

PubMed

Hua, Xin-Tian; Tang, Jun; Mu, De-Zhi

2014-06-01

To evaluate the effect of oral administration of probiotics on intestinal colonization with drug-resistant bacteria among preterm infants in the neonatal intensive care unit (NICU). A double-blind, randomized, placebo-controlled trial was carried out in the preterm infants who were transferred to the NICU immediately after birth. These infants were stratified by whether they were breastfed and then randomized into test group and control group. The test group was given probiotics from the day when enteral feeding began, while the control group was treated conventionally without probiotics. The two groups were compared in terms of the colonization with extended-spectrum beta-lactamase-producing bacteria, as assessed by rectal swabs on days 1, 3, 7, and 14 after birth, and the incidence of diseases. Rectal colonization with drug-resistant bacteria was found in the test group (n=119) and control group (n=138) on days 1, 3, 7, and 14 after birth. There were no significant differences in the incidence of late-onset sepsis and necrotizing enterocolitis between the two groups (P>0.05). Among non-breastfed infants, the test group had significantly decreased rectal colonization with drug-resistant bacteria compared with the control group on day 14 after birth (71.1% vs 88.9%; P=0.04). No probiotic-related adverse events were observed in the study. Oral administration of probiotics may reduce rectal colonization with drug-resistant bacteria in preterm infants under certain conditions and shows good safety.

Transvaginal cervical length and tobacco use in Appalachian women: association with increased risk for spontaneous preterm birth.

PubMed

Findley, Joseph; Seybold, Dara J; Broce, Mike; Yadav, Dolly; Calhoun, Byron C

2015-01-01

Currently ACOG recommends that a mid-term screening strategy may be considered to identify short cervix in low risk populations in an effort to prevent preterm birth. Vaginal progesterone is recommended for women with a cervical length ≤20 mm. Cerclage is recommended for women with prior spontaneous preterm birth who are already receiving progesterone supplementition and CL is <25 mm. This study examined risk factors for spontaneous preterm birth (SPB) <35 weeks among a general obstetrical population prior to these ACOG recommendations. However, cervical cerclage was a possible intervention. Study population included 1,074 patients from 1 Jan 2007-30 Jun 2008 receiving mid-trimester transvaginal ultrasounds during prenatal care at a tertiary medical center clinic. Receiver operator characteristic (ROC) curve cutoff optimal value was ≤34 mm, (n=224), corresponding to 8.9% SPB with shortened cervices compared to 1.4% in patients with normal cervices (>34 mm; n=850; p<0.001 (Area Under the Curve (AUC) 76.6, p<0.001). Cervical lengths <30 mm had 12 times the risk of SPB (p<0.001) while 30-34 mm had 5 times (p=0.005). Tobacco use (≥10 cigarettes per day), p=0.030, and low BMI, p=0.034, had additive effect. Shortened cervical length during routine screening independently predicted SPB while heavy smoking with shortened cervix during pregnancy doubled risk compared to shortened cervix alone.

Transvaginal Cervical Length and Tobacco Use in Appalachian Women: Association with Increased Risk for Spontaneous Preterm Birth

PubMed Central

Findley, Joseph; Seybold, Dara J.; Broce, Mike; Yadav, Dolly; Calhoun, Byron C.

2015-01-01

Currently ACOG recommends that a mid-term screening strategy may be considered to identify short cervix in low risk populations in an effort to prevent preterm birth. Vaginal progesterone is recommended for women with a cervical length ≤20 mm. Cerclage is recommended for women with prior spontaneous preterm birth who are already receiving progesterone supplementation and CL is <25 mm. This study examined risk factors for spontaneous preterm birth (SPB) <35 weeks among a general obstetrical population prior to these ACOG recommendations. However, cervical cerclage was a possible intervention. Study population included 1,074 patients from 1 Jan 2007-30 Jun 2008 receiving mid-trimester transvaginal ultrasounds during prenatal care at a tertiary medical center clinic. Receiver operator characteristic (ROC) curve cutoff optimal value was ≤34 mm, (n=224), corresponding to 8.9% SPB with shortened cervices compared to 1.4% in patients with normal cervices (>34 mm; n=850; p<0.001 (Area Under the Curve (AUC) 76.6, p<0.001). Cervical lengths <30 mm had 12 times the risk of SPB (p<0.001) while 30-34 mm had 5 times (p=0.005). Tobacco use (≥10 cigarettes per day), p=0.030, and low BMI, p=0.034, had additive effect. Shortened cervical length during routine screening independently predicted SPB while heavy smoking with shortened cervix during pregnancy doubled risk compared to shortened cervix alone. PMID:26050294

Umbilical cord blood and maternal visfatin (PBEF/NAMPT) concentrations in preterm birth with and without preterm premature rupture of membranes.

PubMed

Pavlová, Tereza; Zlámal, Filip; Šplíchal, Zbyněk; Tomandl, Josef; Hodická, Zuzana; Ventruba, Pavel; Bienertová-Vašků, Julie

2018-07-01

The aim of the study is to investigate differences in visfatin concentrations between mothers with term and preterm birth (PTB) and between mothers who delivered within seven days and after more than seven days following admission for PTB/preterm premature rupture of membranes (PPROMs). Maternal peripheral blood and cord blood were collected from 56 mothers with PTB (31 with PPROM) and 71 mothers with term delivery (three with PPROM). Maternal visfatin concentration was significantly higher for given gestational age in PTBs compared to term deliveries (p = .021) and also in mothers who delivered within seven days after admission for PTB or PPROM, compared to those who delivered after more than seven days (p = .027; p = .039). Cord blood visfatin concentration was found to be decreased in preterm compared to term infants (p = .007). Visfatin in both maternal and fetal circulation may play an important role in the pathogenesis of PTB/PPROM and could be used to distinguish between women who will deliver in a short period of time after clinical presentation of PTB/PPROM and those who deliver later. Nevertheless, additional research is necessary in order to identify its direct involvement in PTB/PPROM.

Multiple pregnancy, short cervix, part-time worker, steroid use, low educational level and male fetus are risk factors for preterm birth in Japan: a multicenter, prospective study.

PubMed

Shiozaki, Arihiro; Yoneda, Satoshi; Nakabayashi, Masao; Takeda, Yoshiharu; Takeda, Satoru; Sugimura, Motoi; Yoshida, Koyo; Tajima, Atsushi; Manabe, Mami; Akagi, Kozo; Nakagawa, Shoko; Tada, Katsuhiko; Imafuku, Noriaki; Ogawa, Masanobu; Mizunoe, Tomoya; Kanayama, Naohiro; Itoh, Hiroaki; Minoura, Shigeki; Ogino, Mitsuharu; Saito, Shigeru

2014-01-01

To examine the relationship between preterm birth and socioeconomic factors, past history, cervical length, cervical interleukin-8, bacterial vaginosis, underlying diseases, use of medication, employment status, sex of the fetus and multiple pregnancy. In a multicenter, prospective, observational study, 1810 Japanese women registering their future delivery were enrolled at 8⁺⁰ to 12⁺⁶ weeks of gestation. Data on cervical length and delivery were obtained from 1365 pregnant women. Multivariate logistic regression analysis was performed. Short cervical length, steroid use, multiple pregnancy and male fetus were risk factors for preterm birth before 34 weeks of gestation. Multiple pregnancy, low educational level, short cervical length and part-timer were risk factors for preterm birth before 37 weeks of gestation. Multiple pregnancy and cervical shortening at 20-24 weeks of gestation was a stronger risk factor for preterm birth. Any pregnant woman being part-time employee or low educational level, having a male fetus and requiring steroid treatment should be watched for the development of preterm birth. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

Differential brain growth in the infant born preterm: current knowledge and future developments from brain imaging.

PubMed

Counsell, Serena J; Boardman, James P

2005-10-01

Preterm birth is associated with a high prevalence of neuropsychiatric impairment in childhood and adolescence, but the neural correlates underlying these disorders are not fully understood. Quantitative magnetic resonance imaging techniques have been used to investigate subtle differences in cerebral growth and development among children and adolescents born preterm or with very low birth weight. Diffusion tensor imaging and computer-assisted morphometric techniques (including voxel-based morphometry and deformation-based morphometry) have identified abnormalities in tissue microstructure and cerebral morphology among survivors of preterm birth at different ages, and some of these alterations have specific functional correlates. This chapter reviews the literature reporting differential brain development following preterm birth, with emphasis on the morphological changes that correlate with neuropsychiatric impairment.

Maternal stress after preterm birth: Impact of length of antepartum hospital stay.

PubMed

Pichler-Stachl, Elisabeth; Pichler, Gerhard; Baik, Nariae; Urlesberger, Berndt; Alexander, Avian; Urlesberger, Pia; Cheung, Po-Yin; Schmölzer, Georg Marcus

2016-12-01

Preterm birth is associated with increased parental stress, worry, and anxiety, and affects parental-child interactional behaviour. To evaluate the influence of length of antepartum hospital stay on maternal stress after the birth of a preterm infant. A prospective two-centre pilot case-control study was performed at two tertiary level Neonatal-Intensive-Care-Units (NICU). Mothers of preterm infants <36 +0 weeks of gestation admitted to the NICUs were included. The stress of mothers with length of antepartum hospital stay <12h (n=20) were case-matched and compared to that of mothers with length of antepartum hospital stay ≥12h (n=20). Maternal stress was assessed within three days after birth with the Parental-Stress-Scale:NICU (PSS:NICU) questionnaire measuring three scales: "relationship and parental role", "sights and sounds", and "baby looks and behaves". Maternal socio-demographic data were collected by questionnaire administered at the same time. Both groups of mothers had similar socio-demographic data. Stress scale of "sights and sounds" was significantly increased in mothers with antepartum stay ≥12h (2.48±0.69) compared to mothers with antepartum stay <12h (1.95±0.73) (p=0.024). There was no significant difference between the two groups regarding the "looks and behaves" (2.73±0.80 vs. 2.72±0.91; p=0.962) and "relationship and parental role" scales (3.31±1.08 vs. 3.58±1.18; p=0.484). Our study demonstrated higher levels of maternal stress after preterm birth in mothers, who had been admitted to hospital for longer periods of time before delivery. Interventional programmes starting in the antepartum period should be established in order to reduce the burden of stress and to improve parental-child interaction. Copyright © 2016 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Cognitive, motor, behavioural and academic performances of children born preterm: a meta-analysis and systematic review involving 64 061 children.

PubMed

Allotey, J; Zamora, J; Cheong-See, F; Kalidindi, M; Arroyo-Manzano, D; Asztalos, E; van der Post, Jam; Mol, B W; Moore, D; Birtles, D; Khan, K S; Thangaratinam, S

2018-01-01

Preterm birth may leave the brain vulnerable to dysfunction. Knowledge of future neurodevelopmental delay in children born with various degrees of prematurity is needed to inform practice and policy. To quantify the long-term cognitive, motor, behavioural and academic performance of children born with different degrees of prematurity compared with term-born children. PubMed and Embase were searched from January 1980 to December 2016 without language restrictions. Observational studies that reported neurodevelopmental outcomes from 2 years of age in children born preterm compared with a term-born cohort. We pooled individual estimates of standardised mean differences (SMD) and odds ratios (OR) with 95% confidence intervals using a random effects model. We included 74 studies (64 061 children). Preterm children had lower cognitive scores for FSIQ (SMD: -0.70; 95% CI: -0.73 to -0.66), PIQ (SMD: -0.67; 95% CI: -0.73 to -0.60) and VIQ (SMD: -0.53; 95% CI: -0.60 to -0.47). Lower scores for preterm children in motor skills, behaviour, reading, mathematics and spelling were observed at primary school age, and this persisted to secondary school age, except for mathematics. Gestational age at birth accounted for 38-48% of the observed IQ variance. ADHD was diagnosed twice as often in preterm children (OR: 1.6; 95% CI: 1.3-1.8), with a differential effect observed according to the severity of prematurity (I 2 = 49.4%, P = 0.03). Prematurity of any degree affects the cognitive performance of children born preterm. The poor neurodevelopment persists at various ages of follow up. Parents, educators, healthcare professionals and policy makers need to take into account the additional academic, emotional and behavioural needs of these children. Adverse effect of preterm birth on a child's neurodevelopment persists up to adulthood. © 2017 Royal College of Obstetricians and Gynaecologists.

Associations between late and moderately preterm birth and smoking, alcohol, drug use and diet: a population-based case–cohort study

PubMed Central

Smith, Lucy K; Draper, Elizabeth S; Evans, T Alun; Field, David J; Johnson, Samantha J; Manktelow, Bradley N; Seaton, Sarah E; Marlow, Neil; Petrou, Stavros; Boyle, Elaine M

2015-01-01

Objective This study explores the associations between lifestyle factors and late and moderate preterm birth (LMPT: 32+0–36+6 weeks' gestation), a relatively under-researched group. Study design A population-based case–cohort study was undertaken involving 922 LMPT and 965 term (37+ weeks' gestation) singleton live and stillbirths born between 1 September 2009 and 31 December 2010 to women residing in Leicestershire and Nottinghamshire, UK. Poisson multivariable regression models were fitted to estimate relative risks (RR) of LMPT birth associated with maternal smoking, alcohol and recreational drug use, and diet. Results Women who smoked during pregnancy were at 38% increased risk of LMPT birth compared with non-smokers (RR 1.38, 95% CI (1.04 to 1.84)). Low consumption of fruit and vegetables was associated with a 31% increased risk compared with those who reported eating higher consumption levels (RR 1.31 (1.03 to 1.66)). Women who did not have any aspects of a Mediterranean diet were nearly twice as likely to deliver LMPT compared with those whose diet included more Mediterranean characteristics (RR 1.81 (1.04 to 3.14)). Women who smoked and consumed low levels of fruit and vegetables (5% of women) were at particularly high risk (RR=1.81 (1.29 to 2.55)). There was no significant effect of alcohol or recreational drug use on LMPT birth. Conclusions Smoking and poor diet during pregnancy, factors that strongly impact on very preterm birth, are also important at later gestations and experienced together are associated with an elevated rate of risk. Our findings suggest early cessation of smoking during pregnancy may be an effective strategy to reduce LMPT births. PMID:25972442

The development of regional functional connectivity in preterm infants into early childhood.

PubMed

Lee, Wayne; Morgan, Benjamin R; Shroff, Manohar M; Sled, John G; Taylor, Margot J

2013-09-01

Resting state networks are proposed to reflect the neuronal connectivity that underlies cognitive processes. Consequently, abnormal behaviour of these networks due to disease or altered development may predict poor cognitive outcome. To understand how very preterm birth may affect the development of resting state connectivity, we followed a cohort of very preterm-born infants from birth through to 4 years of age using resting state functional MRI. From a larger longitudinal cohort of infants born very preterm (<32 weeks gestational age), 36 at birth, 30 at term, 21 two-year and 22 four-year resting state fMRI datasets were acquired. Using seed-based connectivity analyses with seeds in the anterior cingulate cortex, posterior cingulate cortex, left and right motor-hand regions and left and right temporal lobes, we investigated local and inter-region connectivity as a function of group and age. We found strong local connectivity during the preterm period, which matured into inter-hemispheric and preliminary default-mode network correlations by 4 years of age. This development is comparable to the resting state networks found in term-born infants of equivalent age. The results of this study suggest that differences in developmental trajectory between preterm-born and term-born infants are small and, if present, would require a large sample from both populations to be detected.

Consistency of maternal cognitions and principles across the first five months following preterm and term deliveries

PubMed Central

Winstanley, A.; Sperotto, R.G.; Putnick, D.L.; Cherian, S.; Bornstein, M.H.; Gattis, M.

2014-01-01

The aims of this study were to examine and compare the development of parenting cognitions and principles in mothers following preterm and term deliveries. Parenting cognitions about child development, including thinking that is restricted to single causes and single outcomes (categorical thinking) and thinking that takes into account multiple perspectives (perspectivist thinking), have been shown to relate to child outcomes. Parenting principles about using routines (structure) or infant cues (attunement) to guide daily caregiving have been shown to relate to caregiving practices. We investigated the continuity and stability of parenting cognitions and principles in the days following birth to 5 months postpartum for mothers of infants born term and preterm. All parenting cognitions were stable across time. Categorical thinking increased at a group level across time in mothers of preterm, but not term, infants. Perspectivist thinking increased at a group level for first-time mothers (regardless of birth status) and tended to be lower in mothers of preterm infants. Structure at birth did not predict later structure (and so was unstable) in mothers of preterm, but not term, infants and neither group changed in mean level across time. Attunement was consistent across time in both groups of mothers. These results indicate that prematurity has multiple, diverse effects on parenting beliefs, which may in turn influence maternal behavior and child outcomes. PMID:25459794

GESTATIONAL AGE AT BIRTH AND RISK OF TESTICULAR CANCER

PubMed Central

Crump, Casey; Sundquist, Kristina; Winkleby, Marilyn A.; Sieh, Weiva; Sundquist, Jan

2011-01-01

Most testicular germ cell tumors originate from carcinoma in situ cells in fetal life, possibly related to sex hormone imbalances in early pregnancy. Previous studies of association between gestational age at birth and testicular cancer have yielded discrepant results and have not examined extreme preterm birth. Our objective was to determine whether low gestational age at birth is independently associated with testicular cancer in later life. We conducted a national cohort study of 354,860 men born in Sweden in 1973–1979, including 19,214 born preterm (gestational age <37 weeks) of whom 1,279 were born extremely preterm (22–29 weeks), followed for testicular cancer incidence through 2008. A total of 767 testicular cancers (296 seminomas and 471 nonseminomatous germ cell tumors) were identified in 11.2 million person-years of follow-up. Extreme preterm birth was associated with an increased risk of testicular cancer (hazard ratio 3.95; 95% CI, 1.67–9.34) after adjusting for other perinatal factors, family history of testicular cancer, and cryptorchidism. Only five cases (three seminomas and two nonseminomas) occurred among men born extremely preterm, limiting the precision of risk estimates. No association was found between later preterm birth, post-term birth, or low or high fetal growth and testicular cancer. These findings suggest that extreme but not later preterm birth may be independently associated with testicular cancer in later life. They are based on a small number of cases and will need confirmation in other large cohorts. Elucidation of the key prenatal etiologic factors may potentially lead to preventive interventions in early life. PMID:22314417

Low birthweight and preterm birth rates 1 year before and after the Irish workplace smoking ban.

PubMed

Kabir, Z; Clarke, V; Conroy, R; McNamee, E; Daly, S; Clancy, L

2009-12-01

It is well-established that maternal smoking has adverse birth outcomes (low birthweight, LBW, and preterm births). The comprehensive Irish workplace smoking ban was successfully introduced in March 2004. We examined LBW and preterm birth rates 1 year before and after the workplace smoking ban in Dublin. A cross-sectional observational study analysing routinely collected data using the Euroking K2 maternity system. Coombe University Maternal Hospital. Only singleton live births were included for analyses (7593 and 7648, in 2003 and 2005, respectively). Detailed gestational and clinical characteristics were collected and analysed using multivariable logistic regression analyses and subgroup analyses. Maternal smoking rates, mean birthweights, and adjusted odds ratios (ORs) of LBW and preterm births in 2005 versus 2003. There was a 25% decreased risk of preterm births (OR, 0.75; 95% CI, 0.59-0.96), a 43% increased risk of LBW (OR, 1.43; 95% CI, 1.10-1.85), and a 12% fall in maternal smoking rates (from 23.4 to 20.6%) in 2005 relative to 2003. Such patterns were significantly maintained when specific subgroups were also analysed. Mean birthweights decreased in 2005, but were not significant (P=0.99). There was a marginal increase in smoking cessation before pregnancy in 2005 (P=0.047). Significant declines in preterm births and in maternal smoking rates after the smoking ban are welcome signs. However, the increased LBW birth risks might reflect a secular trend, as observed in many industrialised nations, and merits further investigations.

Season and preterm birth in Norway: A cautionary tale

PubMed Central

Weinberg, Clarice R; Shi, Min; DeRoo, Lisa A; Basso, Olga; Skjærven, Rolv

2015-01-01

Background: Preterm birth is a common, costly and dangerous pregnancy complication. Seasonality of risk would suggest modifiable causes. Methods: We examine seasonal effects on preterm birth, using data from the Medical Birth Registry of Norway (2 321 652 births), and show that results based on births are misleading and a fetuses-at-risk approach is essential. In our harmonic-regression Cox proportional hazards model we consider fetal risk of birth between 22 and 37 completed weeks of gestation. We examine effects of both day of year of conception (for early effects) and day of ongoing gestation (for seasonal effects on labour onset) as modifiers of gestational-age-based risk. Results: Naïve analysis of preterm rates across days of birth shows compelling evidence for seasonality (P < 10−152). However, the reconstructed numbers of conceptions also vary with season (P < 10−307), confounding results by inducing seasonal variation in the age distribution of the fetal population at risk. When we instead properly treat fetuses as the individuals at risk, restrict analysis to pregnancies with relatively accurate ultrasound-based assessment of gestational age (available since 1998) and adjust for socio-demographic factors and maternal smoking, we find modest effects of both time of year of conception and time of year at risk, with peaks for early preterm near early January and early July. Conclusions: Analyses of seasonal effects on preterm birth are demonstrably vulnerable to confounding by seasonality of conception, measurement error in conception dating, and socio-demographic factors. The seasonal variation based on fetuses reveals two peaks for early preterm, coinciding with New Year’s Day and the early July beginning of Norway’s summer break, and may simply reflect a holiday-related pattern of unintended conception. PMID:26045507

Neurobehaviour between birth and 40 weeks’ gestation in infants born <30 weeks’ gestation and parental psychological wellbeing: predictors of brain development and child outcomes

PubMed Central

2014-01-01

Background Infants born <30 weeks’ gestation are at increased risk of long term neurodevelopmental problems compared with term born peers. The predictive value of neurobehavioural examinations at term equivalent age in very preterm infants has been reported for subsequent impairment. Yet there is little knowledge surrounding earlier neurobehavioural development in preterm infants prior to term equivalent age, and how it relates to perinatal factors, cerebral structure, and later developmental outcomes. In addition, maternal psychological wellbeing has been associated with child development. Given the high rate of psychological distress reported by parents of preterm children, it is vital we understand maternal and paternal wellbeing in the early weeks and months after preterm birth and how this influences the parent–child relationship and children’s outcomes. Therefore this study aims to examine how 1) early neurobehaviour and 2) parental mental health relate to developmental outcomes for infants born preterm compared with infants born at term. Methods/Design This prospective cohort study will describe the neurobehaviour of 150 infants born at <30 weeks’ gestational age from birth to term equivalent age, and explore how early neurobehavioural deficits relate to brain growth or injury determined by magnetic resonance imaging, perinatal factors, parental mental health and later developmental outcomes measured using standardised assessment tools at term, one and two years’ corrected age. A control group of 150 healthy term-born infants will also be recruited for comparison of outcomes. To examine the effects of parental mental health on developmental outcomes, both parents of preterm and term-born infants will complete standardised questionnaires related to symptoms of anxiety, depression and post-traumatic stress at regular intervals from the first week of their child’s birth until their child’s second birthday. The parent–child relationship will be assessed at one and two years’ corrected age. Discussion Detailing the trajectory of infant neurobehaviour and parental psychological distress following very preterm birth is important not only to identify infants most at risk, further understand the parental experience and highlight potential times for intervention for the infant and/or parent, but also to gain insight into the effect this has on parent–child interaction and child development. PMID:24758605

Suburban migration and the birth outcome of Chicago-born white and African-American women: the merit of the healthy migrant theory?

PubMed

Collins, James W; Rankin, Kristin M; Janowiak, Christine M

2013-11-01

The healthy migrant theory posits that women who migrate before pregnancy are intrinsically healthier and therefore have better birth outcomes than those who don't move. Objective. To determine whether migration to the suburbs is associated with lower rates of preterm (<37 weeks) birth among Chicago-born White and African-American mothers. We performed stratified and multilevel logistic regression analyses on an Illinois transgenerational dataset of non-Latino White and African-American infants (1989-1991) and their mothers (1956-1976) with appended US census income information. Forty percent of Chicago-born White mothers (N = 45,135) migrated to Suburban Cook County and 30 % migrated to the more geographically distant collar counties. In contrast, 10 % of Chicago-born African-American mothers (N = 41,221) migrated to Suburban Cook and only two percent migrated to the collar counties. Chicago-born White and African-American migrant mothers to Suburban Cook County had lower preterm birth rates than their non-migrant counterparts; RR = 0.8 (0.8-0.9) and 0.8 (0.7-0.8), respectively. When neighborhood income was singularly taken into account, the protective association of suburban migration and preterm birth disappeared among Chicago-born Whites. In race-specific multilevel multivariate regression models which included neighborhood income, the adjusted odds ratio of preterm birth, low birth weight, and small for gestational-age for Chicago-born White and African-American migrant (compared to non-migrant) mothers approximated unity. Neighborhood income underlies the protective association of suburban migration and birth outcome among Chicago-born White and African-American mothers. These findings do not support the healthy migrant hypothesis of reproductive outcome.

Maternal Dietary L-Arginine and Adverse Birth Outcomes in Dar es Salaam, Tanzania.

PubMed

Darling, Anne Marie; McDonald, Chloe R; Urassa, Willy S; Kain, Kevin C; Mwiru, Ramadhani S; Fawzi, Wafaie W

2017-09-01

The amino acid arginine is a physiological precursor to nitric oxide, which is a key mediator of embryonic survival, fetal growth, and pregnancy maintenance. We evaluated the association between consumption of the amino acid arginine and the rate of adverse birth outcomes using data from a double-blind, randomized, placebo-controlled micronutrient supplementation trial among pregnant women in Dar es Salaam, Tanzania (2001-2004). Dietary intakes of arginine were assessed using repeated 24-hour recalls that were administered throughout pregnancy. Participants (n = 7,591) were monitored by research midwives throughout follow-up to assess pregnancy outcomes. Cubic-restricted splines and multivariable log-Poisson regression with empirical standard errors were used to estimate the continuous and categorical associations between arginine intake and adverse birth outcomes. Compared with women within the lowest quintile of arginine intake, those within the highest quintile had 0.79 times the risk of preterm birth before 37 weeks (95% confidence interval: 0.63, 1.00; P = 0.03). The continuous associations of arginine intake with preterm birth before 37 weeks and with preterm birth before 34 weeks were characterized by an initial rapid decrease in risk with increasing intake (P for nonlinearity < 0.01). Arginine intake was not associated with fetal loss or giving birth to infants who were born small for their gestational ages. This data suggest that the association between dietary arginine intake and preterm birth warrants further investigation. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A citywide smoking ban reduced maternal smoking and risk for preterm births: a Colorado natural experiment.

PubMed

Page, Robert Lee; Slejko, Julia F; Libby, Anne M

2012-06-01

Few reports exist on the association of a public smoking ban with fetal outcomes and maternal smoking in the United States. We sought to evaluate the effect of a citywide smoking ban in comparison to a like municipality with no such ban in Colorado on maternal smoking and subsequent fetal birth outcomes. A citywide smoking ban in Colorado provided a natural experiment. The experimental citywide smoking ban site was implemented in Pueblo, Colorado. A comparison community was chosen that had no smoking ban, El Paso County, with similar characteristics of population, size, and geography. The two sites served as their own controls, as each had a preban and postban retrospective observation period: preban was April 1, 2001, to July 1, 2003; postban was April 1, 2004, to July 1, 2006. Outcomes were maternal smoking (self-report), low birth weight (LBW) (defined as <2500 g or as <3000 g), and preterm births (<37 weeks gestation) in singleton births from mothers residing in these cities and reported to the State Department of Public Health. A difference-in-differences estimator was used to account for site and temporal trends in multivariate models. Compared to El Paso County preban, the odds of maternal smoking and preterm births were, respectively, 38% (p<0.05) and 23% (p<0.05) lower in Pueblo. The odds for LBW births decreased by 8% for <3000 g and increased by 8.4% for <2500 g; however, neither was significant. This is the first evidence in the United States that population-level intervention using a smoking ban improved maternal and fetal outcomes, measured as maternal smoking and preterm births.

Neonatal Mortality Risk Associated with Preterm Birth in East Africa, Adjusted by Weight for Gestational Age: Individual Participant Level Meta-Analysis

PubMed Central

Marchant, Tanya; Willey, Barbara; Katz, Joanne; Clarke, Siân; Kariuki, Simon; ter Kuile, Feiko; Lusingu, John; Ndyomugyenyi, Richard; Schmiegelow, Christentze; Watson-Jones, Deborah; Armstrong Schellenberg, Joanna

2012-01-01

Background Low birth weight and prematurity are amongst the strongest predictors of neonatal death. However, the extent to which they act independently is poorly understood. Our objective was to estimate the neonatal mortality risk associated with preterm birth when stratified by weight for gestational age in the high mortality setting of East Africa. Methods and Findings Members and collaborators of the Malaria and the MARCH Centers, at the London School of Hygiene & Tropical Medicine, were contacted and protocols reviewed for East African studies that measured (1) birth weight, (2) gestational age at birth using antenatal ultrasound or neonatal assessment, and (3) neonatal mortality. Ten datasets were identified and four met the inclusion criteria. The four datasets (from Uganda, Kenya, and two from Tanzania) contained 5,727 births recorded between 1999–2010. 4,843 births had complete outcome data and were included in an individual participant level meta-analysis. 99% of 445 low birth weight (<2,500 g) babies were either preterm (<37 weeks gestation) or small for gestational age (below tenth percentile of weight for gestational age). 52% of 87 neonatal deaths occurred in preterm or small for gestational age babies. Babies born <34 weeks gestation had the highest odds of death compared to term babies (odds ratio [OR] 58.7 [95% CI 28.4–121.4]), with little difference when stratified by weight for gestational age. Babies born 34–36 weeks gestation with appropriate weight for gestational age had just three times the likelihood of neonatal death compared to babies born term, (OR 3.2 [95% CI 1.0–10.7]), but the likelihood for babies born 34–36 weeks who were also small for gestational age was 20 times higher (OR 19.8 [95% CI 8.3–47.4]). Only 1% of babies were born moderately premature and small for gestational age, but this group suffered 8% of deaths. Individual level data on newborns are scarce in East Africa; potential biases arising due to the non-systematic selection of the individual studies, or due to the methods applied for estimating gestational age, are discussed. Conclusions Moderately preterm babies who are also small for gestational age experience a considerably increased likelihood of neonatal death in East Africa. Please see later in the article for the Editors' Summary. PMID:22904691

Environmental chemicals and preterm birth: Biological mechanisms and the state of the science

PubMed Central

Ferguson, Kelly K.; Chin, Helen B.

2017-01-01

Purpose of review Preterm birth is a significant worldwide health problem of uncertain origins. The extant body of literature examining environmental contaminant exposures in relation to preterm birth is extensive but results remain ambiguous for most organic pollutants, metals and metalloids, and air pollutants. In the present review we examine recent epidemiologic studies investigating these associations, and identify recent advances and the state of the science. Additionally, we highlight biological mechanisms of action in the pathway between chemical exposures and preterm birth, including inflammation, oxidative stress, and endocrine disruption, that deserve more attention in this context. Recent findings Important advances have been made in the study of the environment and preterm birth, particularly in regard to exposure assessment methods, exploration of effect modification by co-morbidities and exposures, and in identification of windows of vulnerability during gestation. There is strong evidence for an association between maternal exposure to some persistent pesticides, lead, and fine particulate matter, but data on other contaminants is sparse and only suggestive trends can be noted with the current data. Summary Beyond replicating current findings, further work must be done to improve understanding of mechanisms underlying the associations observed between environmental chemical exposures and preterm birth. By examining windows of vulnerability, disaggregating preterm birth by phenotypes, and measuring biomarkers of mechanistic pathways in these epidemiologic studies we can improve our ability to detect associations with exposure, provide additional evidence for causality in an observational setting, and identify opportunities for intervention. PMID:28944158

Environmental chemicals and preterm birth: Biological mechanisms and the state of the science.

PubMed

Ferguson, Kelly K; Chin, Helen B

2017-03-01

Preterm birth is a significant worldwide health problem of uncertain origins. The extant body of literature examining environmental contaminant exposures in relation to preterm birth is extensive but results remain ambiguous for most organic pollutants, metals and metalloids, and air pollutants. In the present review we examine recent epidemiologic studies investigating these associations, and identify recent advances and the state of the science. Additionally, we highlight biological mechanisms of action in the pathway between chemical exposures and preterm birth, including inflammation, oxidative stress, and endocrine disruption, that deserve more attention in this context. Important advances have been made in the study of the environment and preterm birth, particularly in regard to exposure assessment methods, exploration of effect modification by co-morbidities and exposures, and in identification of windows of vulnerability during gestation. There is strong evidence for an association between maternal exposure to some persistent pesticides, lead, and fine particulate matter, but data on other contaminants is sparse and only suggestive trends can be noted with the current data. Beyond replicating current findings, further work must be done to improve understanding of mechanisms underlying the associations observed between environmental chemical exposures and preterm birth. By examining windows of vulnerability, disaggregating preterm birth by phenotypes, and measuring biomarkers of mechanistic pathways in these epidemiologic studies we can improve our ability to detect associations with exposure, provide additional evidence for causality in an observational setting, and identify opportunities for intervention.

Bed rest in singleton pregnancies for preventing preterm birth.

PubMed

Sosa, Claudio G; Althabe, Fernando; Belizán, José M; Bergel, Eduardo

2015-03-30

Bed rest in hospital or at home is widely recommended for the prevention of preterm birth. This advice is based on the observation that hard work and hard physical activity during pregnancy could be associated with preterm birth and with the idea that bed rest could reduce uterine activity. However, bed rest may have some adverse effects on other outcomes. To evaluate the effect of prescription of bed rest in hospital or at home for preventing preterm birth in pregnant women at high risk of preterm birth. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (18 December 2014), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2014, Issue 12), MEDLINE (December 2014), EMBASE (December 2014), LILACS (December 2014), and bibliographies of relevant papers. Randomized, cluster-randomized and quasi-randomized controlled trials with reported data that assess clinical outcomes in women at high risk of spontaneous preterm birth who were prescribed bed rest in hospital or at home for preventing preterm birth, and their babies. Two review authors independently assessed eligibility, trial quality and extracted data. Two studies met the inclusion criteria. One study was not considered for the meta-analysis, since data combined singleton and multiple pregnancies. No differences in any maternal and perinatal outcomes were reported by the authors. This study was at low risk of selection, performance, detection and attrition bias. Only data from one study were included in the meta-analysis (1266 women). This study was at unclear risk of bias for most domains due to lack of reporting. Four hundred and thirty-two women were prescribed bed rest at home and a total of 834 women received a placebo (412) or no intervention (422). Preterm birth before 37 weeks was similar in both groups (7.9% in the intervention group versus 8.5% in the control group; risk ratio (RR) 0.92, 95% confidence interval (CI) 0.62 to 1.37). No other results were reported for any of the other primary or secondary outcomes. There is no evidence, either supporting or refuting the use of bed rest at home or in hospital, to prevent preterm birth. Although bed rest in hospital or at home is widely used as the first step of treatment, there is no evidence that this practice could be beneficial. Due to the potential adverse effects that bed rest could have on women and their families, and the increased costs for the healthcare system, clinicians should discuss the pros and cons of bed rest to prevent preterm birth. Potential benefits and harms should be discussed with women facing an increased risk of preterm birth. Appropriate research is mandatory. Future trials should evaluate both the effectiveness of bed rest, and the effectiveness of the prescription of bed rest, to prevent preterm birth.

Pregnancy loss managed by cervical dilatation and curettage increases the risk of spontaneous preterm birth.

PubMed

McCarthy, Fergus P; Khashan, Ali S; North, Robyn A; Rahma, Muna B; Walker, James J; Baker, Philip N; Dekker, Gus; Poston, Lucilla; McCowan, Lesley M E; O'Donoghue, Keelin; Kenny, Louise C

2013-12-01

Do women with a previous miscarriage or termination of pregnancy have an increased risk of spontaneous preterm birth and is this related to previous cervical dilatation and curettage? A single previous pregnancy loss (termination or miscarriage) managed by cervical dilatation and curettage is associated with a greater risk of SpPTB. Miscarriage affects ∼20% of pregnancies and as many as a further 20% of pregnancies undergo termination. We utilized data from 5575 healthy nulliparous women with singleton pregnancies recruited to the Screening for Pregnancy Endpoints (SCOPE) study, a prospective cohort study performed between November 2004 and January 2011. The primary outcome was spontaneous preterm birth (defined as spontaneous preterm labour or preterm premature rupture of membranes (PPROM) resulting in preterm birth <37 weeks' gestation). Secondary outcomes included PPROM, small for gestational age, birthweight, pre-eclampsia and placental abruption. Women with previous pregnancy loss (miscarriage or termination) were compared with those with no previous pregnancy loss. There were 4331 (78%) women who had no previous pregnancy loss, 974 (17.5%) who had one early previous pregnancy loss, 249 (4.5%) who had two and 21 (0.5%) who had three or four losses. Women with two to four previous losses, but not those with a single loss, had an increased risk of spontaneous preterm birth (adjusted OR 2.12; 95% CI 1.55, 2.90) and/or placental abruption (adjusted OR 2.30; 95% CI 1.36, 3.89) compared with those with no previous pregnancy. A single previous miscarriage or termination of pregnancy where the management involved cervical dilatation and curettage was associated with an increased risk of spontaneous preterm birth (adjusted OR 1.64; 95% CI 1.08, 2.50; 6% absolute risk and adjusted OR 1.83; 95% CI 1.35, 2.48; 7% absolute risk, respectively) compared with those with no previous pregnancy losses. This is in contrast with women with a single previous miscarriage or termination managed non-surgically who showed no increase risk (adjusted OR 0.86; 95% CI 0.38, 1.94; 3.4% absolute risk and adjusted OR 0.87; 95% CI 0.69, 1.12; 3.8% absolute risk, respectively). Although every effort was made to record accurate previous pregnancy data, it was not feasible to confirm the history and management of previous pregnancy loss by hospital records. This may have introduced recall bias. This large prospective cohort study of healthy nulliparous women has demonstrated that women with either a previous miscarriage or termination of pregnancy were at increased risk of spontaneous preterm birth if they were managed by procedures involving cervical dilatation and curettage. However, overall, women with a single pregnancy loss did not have an increased risk of having any other of the adverse pregnancy outcomes examined. In contrast, two to four previous pregnancy losses were associated with an increased risk of having a pregnancy complicated by spontaneous preterm birth and/or placental abruption. Research is required to determine whether non-surgical management of miscarriage or termination of pregnancy should be advocated over surgical treatment. New Zealand: New Enterprise Research Fund, Foundation for Research Science and Technology; Health Research Council; Evelyn Bond Fund, Auckland District Health Board Charitable Trust. Australia: Premier's Science and Research Fund, South Australian Government. Ireland: Health Research Board. Leeds: Cerebra Charity, Carmarthen. Manchester: National Health Service NEAT Grant; Manchester Biotechnology and Biological Sciences Research Council; University of Manchester Proof of Concept Funding. King's College London: Guy's and St Thomas' Charity. King's College London and Manchester: Tommy's-The Baby Charity. N/A.

[Role of donor human milk feeding in preventing nosocomial infection in very low birth weight infants].

PubMed

Bi, Hong-Juan; Xu, Jing; Wei, Qiu-Fen

2018-02-01

To investigate the role of donor human milk in the prevention of nosocomial infection in very low birth weight infants. MeETHODS: A total of 105 hospitalized preterm infants with a very low birth weight were enrolled. They were classified into mother's own milk feeding group, donor human milk feeding group, and preterm formula feeding group, with 35 infants in each group. The three groups were compared in terms of incidence rates of nosocomial infection, necrotizing enterocolitis, and feeding intolerance, time to full enteral feeding, and early growth indices. Compared with the preterm formula feeding group, the donor human milk feeding group and the mother's own milk feeding group had significantly lower incidence rates of nosocomial infection and necrotizing enterocolitis and shorter time to full enteral feeding (P<0.05). There were no significant differences in head circumference, body length, and weight growth velocity among the three groups. Donor human milk can be used in case of a lack of mother's own milk and may help to reduce nosocomial infection.

[Clinical or subclinical hypothyroidism and thyroid autoantibody before 20 weeks pregnancy and risk of preterm birth: a systematic review].

PubMed

Wang, Shaowei; Li, Min; Chu, Defa; Liang, Lin; Zhao, Xiaodong; Zhang, Junrong

2014-11-01

To evaluate the relationship between clinical or subclinical hypothyroidism and positive thyroid autoantibody before 20 weeks pregnancy and risk of preterm birth. Literature search was done in PubMed, EMBASE, Wanfang Medical Database, China Academic Journal Network Publishing Database and China Biology Medicine disc databases from January 1st, 1980 to December 31th, 2013. The following search terms were used:hypothyroidism, subclinical hypothyroidism, hypothyroxinnism, thyroid antibody, preterm labor, preterm birth, etc. (1) Criteria for inclusion:cohort studies and clinical studies were included; only articles that described at least 10 patients were eligible;the exposure was clinical or subclinical hypothyroidism and positive thyroid autoantihody, and outcome was preterm birth. (2) The excluded subjects were articles that described less than 10 patients; controls were pregnant women without eurothyrodisim. Meta-analysis was performed by RevMan 5. The relationship between clinical or subclinical hypothyroidism and positive thyroid autoantibody and risk of preterm birth was evaluated by OR or RR. (1) Twenty cohort studies were enrolled. A total of 39 596 cases of preterm birth occurred among 498 418 pregnant women. The controls in these studies were pregnant women with eurothyrodisim. (2) Clinical hypothyroidism in pregnancy: eight studies were included, reported data on 478 418 pregnant women (5 473 women with clinical hypothyroidism and 472 945 euthyroid pregnant women). The risk of preterm birth in pregnant women with clinical hypothyroidism was higher than those eurothyroid pregnant women in control group (OR = 1.25, 95% CI:1.15-1.36, P < 0.01). (3) Subclinical hypothyroidism in pregnancy: ten studies were included, reported data on 277 531 pregnant women (5 257 women with subclinical hypothyroidism and 272 274 euthyroid pregnant women). The risk of preterm birth in pregnant women with subclinical hypothyroidism was higher than those in control group by random effects analysis (OR = 1.25, 95% CI:1.14-1.36, P < 0.01). (4) Thyroid autoantibodys positive in pregnancy:eleven studies were included, reported data on 28 781 pregnant women (3 036 women with thyroid autoanti body positive and 25 745 euthyroid pregnant women). The risk of preterm birth in pregnant women with positive thyroid autoantibody was higher than those negative thyroid autoantibody in control group (OR = 1.47, 95% CI: 1.27- 1.70, P < 0.01). The funnel plots presented symmetrical graphics, indicating that there was no publication bias. Clinical or subclinical hypothyroidism and positive thyroid autoantibody in pregnant women is risk factors of preterm birth.

Multiple courses of antenatal corticosteroids for preterm birth study: outcomes in children at 5 years of age (MACS-5).

PubMed

Asztalos, Elizabeth V; Murphy, Kellie E; Willan, Andrew R; Matthews, Stephen G; Ohlsson, Arne; Saigal, Saroj; Armson, B Anthony; Kelly, Edmond N; Delisle, Marie-France; Gafni, Amiram; Lee, Shoo K; Sananes, Renee; Rovet, Joanne; Guselle, Patricia; Amankwah, Kofi; Saleem, Mariam; Sanchez, Johanna

2013-12-01

A single course of antenatal corticosteroid therapy is recommended for pregnant women at risk of preterm birth between 24 and 33 weeks' gestational age. However, 50% of women remain pregnant 7 to 14 days later, leading to the question of whether additional courses should be given to women remaining at risk for preterm birth. The Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study (MACS) was an international randomized clinical trial that compared multiple courses of antenatal corticosteroids with a single course in women at risk of preterm birth. To determine the effects of single vs multiple courses of antenatal corticosteroid therapy on death or neurodevelopmental disability (neuromotor, neurosensory, or neurocognitive/neurobehavioral function) at 5 years of age in children whose mothers participated in MACS. Our secondary aims were to determine the effect on height, weight, head circumference, blood pressure, intelligence, and specific cognitive (visual, spatial, and language) skills. Cohort follow-up study of children seen between June 2006 and May 2012 at 55 centers. In total, 1724 women (2141 children) were eligible for the study, of whom 1728 children (80.7% of the 2141 eligible children) participated and 1719 children contributed to the primary outcome. Single and multiple courses of antenatal corticosteroid therapy. The primary outcome was death or survival with a neurodevelopmental disability in 1 of the following domains: neuromotor (nonambulatory cerebral palsy), neurosensory (blindness, deafness, or need for visual/hearing aids), or neurocognitive/neurobehavioral function (abnormal attention, memory, or behavior). There was no significant difference between the groups in the risk of death or neurodevelopmental disability: 217 of 871 children (24.9%) in the multiple-courses group vs 210 of 848 children (24.8%) in the single-course group (odds ratio, 1.02 [95% CI, 0.81 to 1.29]; P = .84). Multiple courses, compared with a single course, of antenatal corticosteroid therapy did not increase or decrease the risk of death or disability at 5 years of age. Because of a lack of strong conclusive evidence of short-term or long-term benefits, it remains our opinion that multiple courses not be recommended in women with ongoing risk of preterm birth. clinicaltrials.gov Identifier: NCT00187382.

Persistent and progressive long-term lung disease in survivors of preterm birth.

PubMed

Urs, Rhea; Kotecha, Sailesh; Hall, Graham L; Simpson, Shannon J

2018-04-13

Preterm birth accounts for approximately 11% of births globally, with rates increasing across many countries. Concurrent advances in neonatal care have led to increased survival of infants of lower gestational age (GA). However, infants born <32 weeks of GA experience adverse respiratory outcomes, manifesting with increased respiratory symptoms, hospitalisation and health care utilisation into early childhood. The development of bronchopulmonary dysplasia (BPD) - the chronic lung disease of prematurity - further increases the risk of poor respiratory outcomes throughout childhood, into adolescence and adulthood. Indeed, survivors of preterm birth have shown increased respiratory symptoms, altered lung structure, persistent and even declining lung function throughout childhood. The mechanisms behind this persistent and sometimes progressive lung disease are unclear, and the implications place those born preterm at increased risk of respiratory morbidity into adulthood. This review aims to summarise what is known about the long-term pulmonary outcomes of contemporary preterm birth, examine the possible mechanisms of long-term respiratory morbidity in those born preterm and discuss addressing the unknowns and potentials for targeted treatments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Decreasing prematurity in twin gestations: predicaments and possibilities.

PubMed

Zork, Noelia; Biggio, Joseph; Tita, Alan; Rouse, Dwight; Gyamfi-Bannerman, Cynthia

2013-08-01

The twin birth rate has been steadily increasing in the United States over the past 10 years attributable in large part to the increased use of reproductive technologies. Despite advancements in the prevention of preterm labor for singletons, the overall rate of preterm birth has decreased only minimally. Several interventions to prevent preterm birth in twins have been studied, but none has proven effective. Inpatient bedrest has not been shown to be effective and can cause significant maternal morbidity. Although intramuscular 17α-hydroxyprogesterone caproate is effective in decreasing the risk of recurrent preterm delivery in singletons, neither it nor cerclage is effective in twin gestations, even in those with a short cervix. However, small trials, subgroup analyses, and a meta-analysis suggest that vaginal progesterone and the Arabin cervical pessary may reduce rates of preterm birth in twins of mothers with a short cervix. Given the current lack of effective therapies to prevent preterm birth in twins, large multicenter trials are needed to assess the effectiveness of vaginal progesterone and pessary in twins of mothers with a short cervix.

LOW PRETERM BIRTH RATE WITH DECREASING EARLY NEONATAL MORTALITY IN BOSNIA AND HERZEGOVINA DURING 2007-2014

PubMed Central

Hudic, Igor; Stray-Pedersen, Babill; Skokic, Fahrija; Fatusic, Zlatan; Zildzic-Moralic, Aida; Skokic, Maida; Fatusic, Jasenko

2016-01-01

The aim: of the study was to determine the situation of preterm births and early neonatal mortality during 2007-2014 in Tuzla Canton, Bosnia and Herzegovina. Methods: The study covers a 8-year period and is based on the protocols at the Tuzla Clinic for Gynecology and Obstetrics that covers all birth in Tuzla Canton area. We analyzed the gestational age of all newborns and recorded the number of neonatal deaths in the first week after birth. Demographics, pregnancy and birth characteristics were collected from the maternal records. Results: The total number of births in the period was 32738. Preterm birth was identified in 2401 (7.3%) cases with 12,5% occurring before 32 gestational weeks and 64% in 35-36 gestational weeks. The mothers of the 24-31 gws preterm group were significantly younger that those in the 32-36 group. In the 32-36 group there were significantly greater proportions of mothers with assisted reproductive technology and pre-eclampsia and 16.7% was medical induced preterm births versus 11.4 % in the 24-31 PTB group, p<0.05. The incidence of PTB did no vary significantly during the period, the lowest rate was found in 2010 (6.4%). A total of 221 children died giving a early mortality rate of 6.8 per 1000 live born over the 8 years. The majority 156 dying infants (70.6%) were preterm, only 5.7% died being born in the 35-36 gestational week (5.9 per 1000). Overall the preterm early mortality (7.3 per 1000) has shown a decreasing tendency during the latter years. Conclusion: During the last 8 years there have been no significant decline in preterm birth in the Tuzla region while a decline in early neonatal death has been registered. PMID:27047264

Threatened preterm labor is a risk factor for impaired cognitive development in early childhood.

PubMed

Paules, Cristina; Pueyo, Victoria; Martí, Elena; de Vilchez, Susana; Burd, Irina; Calvo, Pilar; Oros, Daniel

2017-02-01

Threatened preterm labor is a leading cause of hospital admission during pregnancy. Patients with an episode of threatened preterm labor who deliver at term are considered to have false preterm labor. However, threatened preterm labor has been proposed as a pathologic insult that is not always sufficient to induce irreversible spontaneous preterm birth but that could alter the normal course of pregnancy. The aim of this study was to evaluate threatened preterm labor during pregnancy as a risk factor of neurodevelopmental deficits of children at 2 years of age. Two-year-old children who were born late preterm (n=22) or at term after threatened preterm labor (n=23) were compared with at-term control children (n=42). Neurodevelopment was evaluated at a corrected age of 24-29 months with the use of the Merrill-Palmer-Revised Scales of Development. Children who were born at term after threatened preterm labor had lower scores than control children on global cognitive index (95.4 vs 104.2; P=.011), cognition (95.1 vs 103.1; P=.021), fine motor (95.2 vs 103.4; P=.003), gross motor (84.7 vs 99.8; P=.001), memory (92.9 vs 100.4; P=.015), receptive language (93.9 vs 102.9; P=.03), speed of processing (105.7 vs 113.3; P=.011), and visual motor coordination (98.8 vs 106.7; P=.003) subtests. Children born at term after threatened preterm labor had an increased risk of mild neurodevelopmental delay compared with control children (odds ratio for global cognitive index, 2.06; 95% confidence interval, 1.09-3.88; P=.033). There were no significant differences in any cognitive domain between children who were born late preterm and children who were born at term after threatened preterm labor. Threatened preterm labor is a risk factor for impaired cognitive development at 2 years of age, even if birth occurred at term. Copyright © 2016 Elsevier Inc. All rights reserved.

Preterm Birth: Transition to Adulthood

ERIC Educational Resources Information Center

Allen, Marilee C.; Cristofalo, Elizabeth; Kim, Christina

2010-01-01

Preterm birth is associated with greater difficulty with transitions from childhood to adolescence to adulthood. Adolescents and young adults born preterm have higher rates of cerebral palsy, intellectual disability, cognitive impairment, learning disability, executive dysfunction, attention deficit disorder, and social-emotional difficulties than…

Ambient air pollution and adverse birth outcomes: Differences by maternal comorbidities.

PubMed

Lavigne, Eric; Yasseen, Abdool S; Stieb, David M; Hystad, Perry; van Donkelaar, Aaron; Martin, Randall V; Brook, Jeffrey R; Crouse, Daniel L; Burnett, Richard T; Chen, Hong; Weichenthal, Scott; Johnson, Markey; Villeneuve, Paul J; Walker, Mark

2016-07-01

Prenatal exposure to ambient air pollution has been associated with adverse birth outcomes, but the potential modifying effect of maternal comorbidities remains understudied. Our objective was to investigate whether associations between prenatal air pollution exposures and birth outcomes differ by maternal comorbidities. A total of 818,400 singleton live births were identified in the province of Ontario, Canada from 2005 to 2012. We assigned exposures to fine particulate matter (PM2.5), nitrogen dioxide (NO2) and ozone (O3) to maternal residences during pregnancy. We evaluated potential effect modification by maternal comorbidities (i.e. asthma, hypertension, pre-existing diabetes mellitus, heart disease, gestational diabetes and preeclampsia) on the associations between prenatal air pollution and preterm birth, term low birth weight and small for gestational age. Interquartile range (IQR) increases in PM2.5 (2μg/m(3)), NO2 (9ppb) and O3 (5ppb) over the entire pregnancy were associated with a 4% (95% CI: 2.4-5.6%), 8.4% (95% CI: 5.5-10.3%) and 2% (95% CI: 0.5-4.1%) increase in the odds of preterm birth, respectively. Increases of 10.6% (95% CI: 0.2-2.1%) and 23.8% (95% CI: 5.5-44.8%) in the odds of preterm birth were observed among women with pre-existing diabetes while the increases were of 3.8% (95% CI: 2.2-5.4%) and 6.5% (95% CI: 3.7-8.4%) among women without this condition for pregnancy exposure to PM2.5 and NO2, respectively (Pint<0.01). The increase in the odds of preterm birth for exposure to PM2.5 during pregnancy was higher among women with preeclampsia (8.3%, 95% CI: 0.8-16.4%) than among women without (3.6%, 95% CI: 1.8-5.3%) (Pint=0.04). A stronger increase in the odds of preterm birth was found for exposure to O3 during pregnancy among asthmatic women (12.0%, 95% CI: 3.5-21.1%) compared to non-asthmatic women (2.0%, 95% CI: 0.1-3.5%) (Pint<0.01). We did not find statistically significant effect modification for the other outcomes investigated. Findings of this study suggest that associations of ambient air pollution with preterm birth are stronger among women with pre-existing diabetes, asthma, and preeclampsia. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Global report on preterm birth and stillbirth (2 of 7): discovery science

PubMed Central

2010-01-01

Background Normal and abnormal processes of pregnancy and childbirth are poorly understood. This second article in a global report explains what is known about the etiologies of preterm births and stillbirths and identifies critical gaps in knowledge. Two important concepts emerge: the continuum of pregnancy, beginning at implantation and ending with uterine involution following birth; and the multifactorial etiologies of preterm birth and stillbirth. Improved tools and data will enable discovery scientists to identify causal pathways and cost-effective interventions. Pregnancy and parturition continuum The biological process of pregnancy and childbirth begins with implantation and, after birth, ends with the return of the uterus to its previous state. The majority of pregnancy is characterized by rapid uterine and fetal growth without contractions. Yet most research has addressed only uterine stimulation (labor) that accounts for <0.5% of pregnancy. Etiologies The etiologies of preterm birth and stillbirth differ by gestational age, genetics, and environmental factors. Approximately 30% of all preterm births are indicated for either maternal or fetal complications, such as maternal illness or fetal growth restriction. Commonly recognized pathways leading to preterm birth occur most often during the gestational ages indicated: (1) inflammation caused by infection (22-32 weeks); (2) decidual hemorrhage caused by uteroplacental thrombosis (early or late preterm birth); (3) stress (32-36 weeks); and (4) uterine overdistention, often caused by multiple fetuses (32-36 weeks). Other contributors include cervical insufficiency, smoking, and systemic infections. Many stillbirths have similar causes and mechanisms. About two-thirds of late fetal deaths occur during the antepartum period; the other third occur during childbirth. Intrapartum asphyxia is a leading cause of stillbirths in low- and middle-income countries. Recommendations Utilizing new systems biology tools, opportunities now exist for researchers to investigate various pathways important to normal and abnormal pregnancies. Improved access to quality data and biological specimens are critical to advancing discovery science. Phenotypes, standardized definitions, and uniform criteria for assessing preterm birth and stillbirth outcomes are other immediate research needs. Conclusion Preterm birth and stillbirth have multifactorial etiologies. More resources must be directed toward accelerating our understanding of these complex processes, and identifying upstream and cost-effective solutions that will improve these pregnancy outcomes. PMID:20233383

Increased risks of preterm birth and a low-birth-weight baby in Thai human immunodeficiency virus-positive pregnant women with periodontitis.

PubMed

Pattrapornnan, Pakkaporn; DeRouen, Timothy A; Songpaisan, Yupin

2012-11-01

Many studies have investigated the risks of adverse neonatal outcomes associated with the presence of periodontitis in non-human immunodeficiency virus (HIV)-infected pregnant women. To the best of our knowledge, there has been no study to investigate the risk of neonatal outcomes associated with periodontitis in HIV-infected pregnant women. The aim of this study is to measure the risk of having adverse neonatal outcomes: preterm delivery (<37 weeks of gestation), low birth weight (<2500 g at birth), and preterm and low-birth-weight baby (<37 weeks of gestation and <2500 g at birth) associated with the presence of periodontitis in HIV-infected women. A total of 292 HIV-infected pregnant women were interviewed for demographic information and medical history and were examined for their periodontal status during weeks 16 to 34 of gestation. Follow-up sessions were done after the delivery to record the baby's data. Periodontitis defined by various criteria were evaluated as exposures. Binomial regression (generalized linear model) was used to examine the risk ratios (RRs). Logistic regression, t tests, and χ2 test were used to examine the associations of periodontitis with adverse neonatal outcomes. Forty women had preterm delivery, 39 women delivered a low-birth-weight baby, and 22 women gave birth to a baby that was preterm and low birth weight. We found significant elevated risks of having preterm delivery as RR = 3.08, 95% confidence interval (CI) = 1.29 to 7.38, low birth weight RR = 2.55, 95% CI = 1.04 to 2.65, and preterm and low birth weight as RR = 4.08, 95% CI = 1.55 to 10.76 in women who had at ≥1 5-mm periodontal pocket. This study found a positive risk of adverse neonatal outcomes in HIV-infected pregnant women who had moderate periodontitis.

Hydroxychloroquine Use in Lupus Patients during Pregnancy Is Associated with Longer Pregnancy Duration in Preterm Births.

PubMed

Kroese, S J; de Hair, M J H; Limper, M; Lely, A T; van Laar, J M; Derksen, R H W M; Fritsch-Stork, R D E

2017-01-01

To investigate the effect of hydroxychloroquine (HCQ) in pregnant women with systemic lupus erythematosus (SLE). In SLE pregnancies of a single Dutch center (2000-2015), lupus activity and flares before and during pregnancy and postpartum were assessed using the SLE Disease Activity Index (SLEDAI)/SLEPDAI (SLEDAI adjusted for pregnancy). The association between HCQ use and pregnancy outcomes (early spontaneous abortion, fetal death, and preterm and term live birth) was analyzed using generalized estimating equations (GEE) accounting for the occurrence of multiple pregnancies per patient. Analyses were adjusted for antiphospholipid antibody (aPL) status. 110 pregnancies (63 mostly Caucasian patients) were included, of which, in 30, HCQ was used; overall occurrence of flares was low (non-HCQ group: 5 mild (6.4%) and 2 severe (2.6%); HCQ group: 2 mild (6.7%) and no severe flares). The HCQ group showed a trend towards lower dosage of prednisone (OR 0.2 (95% CI 0.0-1.4); p = 0.10). Pregnancy outcomes were comparable between groups. Among preterm live births, pregnancy duration was significantly longer in HCQ users (2.4 weeks (95% CI 1.0-3.8; p ≤ 0.001)). HCQ use was associated with longer pregnancy duration in the vulnerable preterm birth population, underscoring the beneficial effect of HCQ use during pregnancy.

THE INFLUENCE OF GESTATIONAL AGE AND BIRTH WEIGHT OF THE NEWBORN ON TOOTH ERUPTION

PubMed Central

Ramos, Sandra Regina Piovezani; Gugisch, Renato Cordeiro; Fraiz, Fabian Calixto

2006-01-01

Objective: The aim of the present study was to compare the beginning of eruption of the first deciduous tooth in preterm infants (<38 weeks) with full-term infants (38 and 42 weeks) of normal birth weight (32.500g), low birth weight (< 2.500g) and very low birth weight (<1.500g), in order to evaluate if premature birth and low birth weight would affect tooth eruption. Methods: The neonatal records and the moment of eruption of the first deciduous tooth of 146 infants - 77 preterm infants and 69 full-term infants, ranging from 5 to 36 months old, of both genders – were recorded. All of them were under care at the Pediatric Ambulatory of Hospital Universitário Evangélico at Curitiba – Parana. Data were analyzed considering biological age and post-conception, or corrected, age – which is the gestational age plus the infant's chronological age at the month of eruption of the first deciduous tooth. Results: Results showed that when chronological age is considered, tooth eruption in preterm and very low birth weight infants is importantly delayed. However, when corrected age is considered, no statistically significant differences were found among groups. Conclusion: The delayed eruption may be related to the premature birth and not to a delay in dental development. PMID:19089267

Inattention and development of toddlers born in preterm and with low birth weight.

PubMed

Huang, June-Hui; Huang, Huei-Lin; Chen, Hsiu-Lin; Lin, Lung-Chang; Tseng, Hsing-I; Kao, Tsung-Jen

2012-07-01

The objective of this study was to examine the impact of low birth weight and preterm birth on a toddler's inattention and development, including cognitive, language, motor, social-emotional and adaptive behaviors. A total of 105 toddlers enrolled for the study; they were divided into four groups: 40 full-term and normal birth weight (NBW, birth weight greater than 2500 g) toddlers, 24 moderate birth weight (MLBW, birth weight between 2499 and 1500 g) toddlers, 20 very to extremely low birth weight (V-ELBW, 12 between 1000 and 1499 g and 8 lower than 1000 g) toddlers, and 21 term toddlers who were recruited from a clinic of developmental delay as the developmental delay at risk (DDR) group. The Bayley Scales of Infant and Toddler Development-Third Edition (BSID-III) and Disruptive Behavior Rating Scale-Toddler were used. The findings were as follows: (1) DDR group performed worst in BSID-III; (2) although there were no statistical differences among the NBW, MLBW, and V-ELBW groups in BSID-III, the lower the birth weight, the lower the average performance, especially in language, adaptive social behavior, and adaptive practical behavior; and (3) comparing the inattention score, the DDR group was the poorest, normal and V-ELBW groups were the best, and MLBW group was in the middle. In conclusion, low birth weight and preterm delivery affected children's inattention and development of language, adaptive social behavior, and adaptive practical behavior. Copyright © 2012. Published by Elsevier B.V.

Pre- and Post-ductal oxygen saturation among apparently healthy low birth weight neonates.

PubMed

Odudu, Leo A; Ezenwa, Beatrice N; Esezobor, Christopher I; Ekure, Ekanem N; Egri Okwaji, Mathias T C; Ezeaka, Chinyere V; Njokanma, Fidelis O; Ladele, Jejelola

2017-01-01

Reference values of oxygen saturation (SpO2) to guide care of low birth weight neonates have been obtained mainly from Caucasians. Data from African newborns are lacking. To determine the pre- and post-ductal SpO2values of low birth weight neonates within the first 72 h of life, compare SpO2values of moderate-late preterm and term low birth weight neonates and determine how mode of delivery affected SpO2in the first 24 h of life. An observational descriptive study was carried out on apparently healthy low birth weight newborns weighing 1500 to ≤2499 g. Pre and post ductal SpO2values were recorded at the following hours of life: 10-24 h, >24-48 h and >48-72 h using a NONIN® pulse oximeter. The ranges of pre- and post-ductal SpO2in the study were similar for both preterm and term neonates in the study (89%-100%). The mean (standard deviation [SD]) pre-ductal SpO2was 95.9% (2.3) and the mean (SD) post-ductal SpO2was 95.9% (2.1). There was a significant increase in pre-ductal SpO2from 10 to 24 h through >48-72 h of life (P = 0.027). The mode of delivery did not affect SpO2values within 10-24 h of life. The present study documented daily single pre- and post-ductal SpO2 values for preterm and term low birth weight neonates weighing 1500 g to <2500 g during the first 72 h of life. The overall range and mean pre- and post-ductal SpO2 were similar for both categories of stable low birth weight neonates in the study. There was no significant difference between SpO2ranges for late preterm compared to term low birth weight neonates. The results obtained could serve as guide in assessing SpO2of low birth weight neonates weighing between 1500 and 2499 g in the first 72 h of life.

Effect of ambient temperature and air pollutants on the risk of preterm birth, Rome 2001-2010.

PubMed

Schifano, Patrizia; Lallo, Adele; Asta, Federica; De Sario, Manuela; Davoli, Marina; Michelozzi, Paola

2013-11-01

Although the prevalence of preterm births ranges from 5 to 13% and represents the leading cause of perinatal mortality and morbidity in developed countries, the etiology of preterm birth remains uncertain. We aimed to evaluate the effect of short-term exposure to high and low temperatures and air pollution on preterm delivery and to identify socio-demographic and clinical maternal risk factors enhancing individual susceptibility. We analyzed all singleton live births by natural delivery that occurred in Rome in 2001-2010. A time-series approach was used to estimate the effect of exposure to minimum temperature, maximum apparent temperature, heat waves, particulate matter with an aerodynamic diameter of 10μm or less (PM10), ozone, and nitrogen dioxide in the month preceding delivery; the analysis was conducted separately for cold and warm seasons. Socio-demographic and clinical risk factors were included as interaction terms. Preterm births comprised nearly 6% of our cohort. An increase of 1.9% (95% confidence interval (CI) 0.86-2.87) in daily preterm births per 1°C increase in maximum apparent temperature in the 2days preceding delivery was estimated for the warm season. Older women, women with higher education levels, and women with obstetric or chronic pathologies reported during delivery had a lower effect of temperature on the risk of preterm birth, while women with a chronic disease in the two years before delivery and mothers<20years showed a higher effect. A +19% (95% CI 7.91-31.69) increase in preterm births was observed during heat waves. Temperature had no effect during the cold season. We detected a significant effect of PM10 on preterm-birth risk at a lag period of 12-22days during the warm season (+0.69%; 95% CI 0.23-1.15, for 1μg/m(3) increase of pollutant); women with obstetric pathologies and with a higher education level showed a higher risk. Our results suggest a possible short-term effect of heat and a more delayed and prolonged effect of PM10 exposure on preterm-birth risk, as well as the existence of more susceptible subgroups of women. Our observations support the few reported investigations, and may help to increase awareness among public-health stakeholders and clinicians regarding the role of these environmental exposures as risk factors for premature birth and health consequences for children later in life. © 2013.

Prenatal hazardous substance use and adverse birth outcomes

PubMed Central

Quesada, Odayme; Gotman, Nathan; Howell, Heather B.; Funai, Edmund F.; Rounsaville, Bruce J.; Yonkers, Kimberly A.

2012-01-01

Objective Assess the relative effects of a variety of illicit and licit drugs on risk for adverse birth outcomes. Methods We used data from two large prospective investigations, and a novel analytic method, recursive partitioning class analysis to identify risk factors associated with preterm birth and delivering a small for gestational age infant. Results Compared to cocaine and opiate non-users, cocaine users were 3.53 times as likely (95% Cl: 1.65–7.56; p=0.001) and opiate users 2.86 times as likely (95% Cl: 1.11–7.36; p=0.03) to deliver preterm. The odds of delivering a small for gestational age infant for women who smoked more than two cigarettes daily was 3.74, (95% Cl: 2.47–5.65; p<0.0001) compared to women who smoked two or less cigarettes daily and had one previous child. Similarly, less educated, nulliparous women who smoked two or fewer cigarettes daily were 4.12 times as likely (95% Cl: 2.04–8.34; p<0.0001) to have a small for gestational age infant. Conclusions Among our covariates, prenatal cocaine and opiate use are the predominant risk factors for preterm birth; while tobacco use was the primary risk factor predicting small for gestational age at delivery. Multi-substance use did not substantially increase risk of adverse birth outcomes over these risk factors. PMID:22489543

Effectiveness of a cervical pessary for women who did not deliver 48 h after threatened preterm labor (Assessment of perinatal outcome after specific treatment in early labor: Apostel VI trial).

PubMed

Hermans, Frederik J R; Schuit, Ewoud; Opmeer, Brent C; Oudijk, Martijn A; Bekker, Mireille; Woiski, Mallory; Bax, Caroline J; Sueters, Marieke; Scheepers, Hubertina C J; Franssen, Maureen T M; Pajkrt, Eva; Mol, Ben Willem J; Kok, Marjolein

2016-07-12

Preterm birth is a major cause of neonatal mortality and morbidity. As preventive strategies are largely ineffective, threatened preterm labor is a frequent problem that affects approximately 10 % of pregnancies. In recent years, risk assessment in these women has incorporated cervical length measurement and fetal fibronectin testing, and this has improved the capacity to identify women at increased risk for delivery within 14 days. Despite these improvements, risk for preterm birth continues to be increased in women who did not deliver after an episode of threatened preterm labor, as indicated by a preterm birth rate between 30 to 60 % in this group of women. Currently no effective treatment is available. Studies on maintenance tocolysis and progesterone have shown ambiguous results. The pessary has not been evaluated in women with threatened preterm labor, however studies in asymptomatic women with a short cervix show reduced rates of preterm birth rates as well as perinatal complications. The APOSTEL VI trial aims to assess the effectiveness of a cervical pessary in women who did not deliver within 48 h after an episode of threatened preterm labor. This is a nationwide multicenter open-label randomized clinical trial. Women with a singleton or twin gestation with intact membranes, who were admitted for threatened preterm labor, at a gestational age between 24 and 34 weeks, a cervical length between 15 and 30 mm and a positive fibronectin test or a cervical length below 15 mm, who did not deliver after 48 h will be eligible for inclusion. Women will be allocated to a pessary or no intervention (usual care). Primary outcome is preterm delivery < 37 weeks. Secondary outcomes are amongst others a composite of perinatal morbidity and mortality. Sample size is based on an expected 50 % reduction of preterm birth before 37 weeks (two-sided test, α 0.05 and β 0.2). Two hundred women with a singleton pregnancy need to be randomized. Analysis will be done by intention to treat. The APOSTEL VI trial will provide evidence whether a pessary is effective in preventing preterm birth in women who did not deliver 48 h after admission for threatened preterm labor and who remain at high risk for preterm birth. Trial is registered at the Dutch Trial Register: http://www.trialregister.nl , NTR4210, date of registration: October 16th 2013.

Visuospatial perception in children born preterm with no major neurological disorders.

PubMed

Butcher, Phillipa R; Bouma, Anke; Stremmelaar, Elisabeth F; Bos, Arend F; Smithson, Michael; Van Braeckel, Koenraad N J A

2012-11-01

Many investigations have found deficits in visuospatial perception in children born preterm, however, it is not clear whether the deficits are specific to visuospatial perception or the consequences of deficits in other functional areas, which often accompany preterm birth. This study investigated whether children born preterm show a specific deficit in visuospatial perception. Fifty-six 7- to 11-year-old preterm born children (gestational age <34 weeks) without cerebral palsy and 51 age-matched, full-term children completed four computerized tasks tapping different levels and types of visuospatial perception. Accuracy and speed of responses were recorded. Task formats were designed to reduce demands on attentional deployment. Measures of intelligence and parental education were included in the analysis. Children born preterm performed less accurately and/or less rapidly on all tasks. Their poorer performance did not reflect differences in speed-accuracy trade-off. Parental education and IQ, both significantly lower in the preterm children, contributed positively to performance on all tasks. IQ mediated the association between preterm birth and visuospatial performance on the most cognitively demanding task. Children born preterm performed more poorly than full-term controls on four visuospatial perceptual tasks. Although intelligence and parental education were also associated with performance, preterm birth contributed independently of these factors on three of four tasks. Many children born preterm are thus multiply disadvantaged on visuospatial tasks: the lower IQ scores and parental educational levels frequently found in this group increase the deficit associated with preterm birth. (c) 2012 APA, all rights reserved.

Impact of cesarean section on intermediate and late preterm births: United States, 2000-2003.

PubMed

Malloy, Michael H

2009-03-01

Cesarean section appears to be associated with increased risk of neonatal mortality among infants of low-risk term pregnancies, but it may offer some survival advantage among the most extremely preterm infants. The impact on intermediate (32-33 wk) and late preterm (34-36 wk) deliveries remains uncertain. The objective of this analysis was to compare the neonatal mortality rate (death at 0-27 days), the mechanical ventilation usage rate, and the incidence of hyaline membrane disease among intermediate and late preterm infants delivered by primary cesarean section compared with those delivered vaginally. United States Linked Birth and Infant Death Certificate files from the years 2000 to 2003 were used. Maternal demographic characteristics, medical complications, and labor and delivery complications were abstracted from the files along with infant information. Because of concern for misclassification of gestational age, a procedure was used to trim away births in which the birthweight of an infant for a specific gestational age was inconsistent. Adjusted odds ratios were calculated using logistic regression for the risk of the three outcomes of interest relative to the mode of delivery. A total of 422,001 live births were available with complete data from the trimmed data set (60% of untrimmed data). After adjustment by logistic regression for infant size at birth, birthweight, sex, Apgar score at 5 minutes less than 4, multiple births, breech presentation, presence of an anomaly, the presence of any maternal medical condition or complication of labor and delivery, labor induction, maternal race, age, education, and gravidity, the adjusted odds ratios (95% CI for neonatal mortality at gestational ages of 32, 33, 34, 35, and 36 wk) were, respectively, 1.69 (1.31-2.20), 1.79 (1.40-2.29), 1.08 (0.83-1.40), 2.31 (1.78-3.00), and 1.98 (1.50-2.62). These data suggest that for low-risk preterm infants at 32 to 36 weeks' gestation, independent of any reported risk factors, primary cesarean section may pose an increased risk of neonatal mortality and morbidity.

Antenatal corticosteroids for women at risk of imminent preterm birth in low-resource countries: the case for equipoise and the need for efficacy trials.

PubMed

Vogel, Joshua P; Oladapo, Olufemi T; Pileggi-Castro, Cynthia; Adejuyigbe, Ebunoluwa A; Althabe, Fernando; Ariff, Shabina; Ayede, Adejumoke Idowu; Baqui, Abdullah H; Costello, Anthony; Chikamata, Davy M; Crowther, Caroline; Fawole, Bukola; Gibbons, Luz; Jobe, Alan H; Kapasa, Monica Lulu; Kinuthia, John; Kriplani, Alka; Kuti, Oluwafemi; Neilson, James; Patterson, Janna; Piaggio, Gilda; Qureshi, Rahat; Qureshi, Zahida; Sankar, Mari Jeeva; Stringer, Jeffrey S A; Temmerman, Marleen; Yunis, Khalid; Bahl, Rajiv; Metin Gülmezoglu, A

2017-01-01

The scientific basis for antenatal corticosteroids (ACS) for women at risk of preterm birth has rapidly changed in recent years. Two landmark trials-the Antenatal Corticosteroid Trial and the Antenatal Late Preterm Steroids Trial-have challenged the long-held assumptions on the comparative health benefits and harms regarding the use of ACS for preterm birth across all levels of care and contexts, including resource-limited settings. Researchers, clinicians, programme managers, policymakers and donors working in low-income and middle-income countries now face challenging questions of whether, where and how ACS can be used to optimise outcomes for both women and preterm newborns. In this article, we briefly present an appraisal of the current evidence around ACS, how these findings informed WHO's current recommendations on ACS use, and the knowledge gaps that have emerged in the light of new trial evidence. Critical considerations in the generalisability of the available evidence demonstrate that a true state of clinical equipoise exists for this treatment option in low-resource settings. An expert group convened by WHO concluded that there is a clear need for more efficacy trials of ACS in these settings to inform clinical practice.

Providing active antenatal care depends on the place of birth for extremely preterm births: the EPIPAGE 2 cohort study.

PubMed

Diguisto, Caroline; Goffinet, François; Lorthe, Elsa; Kayem, Gilles; Roze, Jean-Christophe; Boileau, Pascal; Khoshnood, Babak; Benhammou, Valérie; Langer, Bruno; Sentilhes, Loic; Subtil, Damien; Azria, Elie; Kaminski, Monique; Ancel, Pierre-Yves; Foix-L'Hélias, Laurence

2017-11-01

Survival rates of infants born before 25 weeks of gestation are low in France and have not improved over the past decade. Active perinatal care increases these infants' likelihood of survival. Our aim was to identify factors associated with active antenatal care, which is the first step of proactive perinatal care in extremely preterm births. The population included 1020 singleton births between 22 0/6 and 26 0/6 weeks of gestation enrolled in the Etude Epidémiologique sur les Petits Ages Gestationnels 2 study, a French national population-based cohort of very preterm infants born in 2011. The main outcome was 'active antenatal care' defined as the administration of either corticosteroids or magnesium sulfate or delivery by caesarean section for fetal rescue. A multivariable analysis was performed using a two-level multilevel model taking into account the maternity unit of delivery to estimate the adjusted ORs (aORs) of receiving active antenatal care associated with maternal, obstetric and place of birth characteristics. Among the population of extremely preterm births, 42% received active antenatal care. After standardisation for gestational age, regional rates of active antenatal care varied between 22% (95% CI 5% to 38%) and 61% (95% CI 44% to 78%). Despite adjustment for individual and organisational characteristics, active antenatal care varied significantly between maternity units (p=0.03). Rates of active antenatal care increased with gestational age with an aOR of 6.46 (95% CI 3.40 to 12.27) and 10.09 (95% CI 5.26 to 19.36) for infants born at 25 and 26 weeks' gestation compared with those born at 24 weeks. No other individual characteristic was associated with active antenatal care. Even after standardisation for gestational age, active antenatal care in France for extremely preterm births varies widely with place of birth. The dependence of life and death decisions on place of birth raises serious ethical questions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The effect of preterm birth on vestibular evoked myogenic potentials in children.

PubMed

Eshaghi, Zahra; Jafari, Zahra; Shaibanizadeh, Abdolreza; Jalaie, Shohreh; Ghaseminejad, Azizeh

2014-01-01

Preterm birth is a significant global health problem with serious short- and long-term consequences. This study examined the long term effects of preterm birth on vestibular evoked myogenic potentials (VEMPs) among preschool-aged children. Thirty-one children with preterm and 20 children with term birth histories aged 5.5 to 6.5 years were studied. Each child underwent VEMPs testing using a 500 Hz tone-burst stimulus with a 95 dB nHL (normal hearing level) intensity level. The mean peak latencies of the p13 and n23 waves in the very preterm group were significantly longer than for the full-term group (p≤ 0.041). There was a significant difference between very and mildly preterm children in the latency of peak p13 (p= 0.003). No significant differences existed between groups for p13-n23 amplitude and the interaural amplitude difference ratio. The tested ear and gender did not affect the results of the test. Prolonged VEMPs in very preterm children may reflect neurodevelopmental impairment and incomplete maturity of the vestibulospinal tract (sacculocollic reflex pathway), especially myelination. VEMPs is a non-invasive technique for investigating the vestibular function in young children, and considered to be an appropriate tool for evaluating vestibular impairments at the low brainstem level. It can be used in follow-ups of the long-term effects of preterm birth on the vestibular system.

The effects of standing, lifting and noise exposure on preterm birth, growth restriction, and perinatal death in healthy low-risk working military women.

PubMed

Magann, Everett F; Evans, Sharon F; Chauhan, Suneet P; Nolan, Thomas E; Henderson, Jenni; Klausen, Jack H; Newnham, John P; Morrison, John C

2005-09-01

The effects of standing, lifting and noise in low-risk, healthy pregnant women are uncertain. In the past, the heterogeneity of the populations studied, the limitations of the designs of the retrospective and case control studies, and a failure of some of the larger investigations to evaluate all the potential confounding variables has hampered many studies. The purpose of this investigation was to evaluate, throughout pregnancy, the effects of standing, repetitive lifting, and noise in the workplace compared with no standing, lifting or noise exposure, on maternal and perinatal outcomes in a large prospective study of a low-risk healthy population of working women cared for by a single group of health providers. This prospective observational study used an extensive questionnaire to collect antepartum, intrapartum, and postpartum information. Information was collected on the initial visit, each subsequent visit, and immediately after delivery. The participating women were divided into groups based on the amount of time spent standing, the amount and extent of repetitive lifting, and noise exposure in the workplace. Eight hundred and fourteen low-risk active duty women participated in this investigation over a 4-year period. Multivariate analysis with non-exposure compared with exposure reinforced the effect of standing on preterm labor (OR 1.80, 95% CI 1.05, 3.16) and preterm birth (OR 1.69, 95% CI 1.03, 2.80) and showed a trend toward an effect of noise exposure on preterm labor (OR 1.76, 95% CI 0.78, 3.39) after controlling for other exposures. This investigation suggests an association of occupational standing with preterm labor and preterm birth.

Impact of very preterm birth on health care costs at five years of age.

PubMed

Korvenranta, Emmi; Lehtonen, Liisa; Rautava, Liisi; Häkkinen, Unto; Andersson, Sture; Gissler, Mika; Hallman, Mikko; Leipälä, Jaana; Peltola, Mikko; Tammela, Outi; Linna, Miika

2010-05-01

We assessed the effects of very preterm birth (gestational age <32 weeks or birth weight <1501 g) and prematurity-related morbidities on health care costs during the fifth year of life. The study population consisted of 588 very preterm children and 176 term control subjects born in 2001-2002. Costs of hospitalizations, visits to health care professionals and therapists, and the use of other social welfare services were assessed during the fifth year of life. Hospital visits were derived from register data and other health care contacts, and the use of social welfare services were derived from parental reports. The effects of 6 prematurity-related morbidities (cerebral palsy [CP], seizure disorder, obstructive airway disease, hearing loss, visual disturbances or blindness, and other ophthalmologic problems) on the costs of health care were studied. The average health care costs during the fifth year of life were 749 euro in the term control subjects, 1023 euro in the very preterm children without morbidities, and 3265 euro in those with morbidities. The costs of social welfare services and therapies exceeded the hospitalization costs in all groups. Among children who were born preterm, CP was associated with 5125 euro higher costs, whereas later obstructive airway diseases increased the costs by 819 euro compared with individuals without these morbidities. The health care costs during the fifth year of life in very preterm children with morbidities were 4.4-fold and in those without morbidities 1.4-fold compared with those of term control subjects. This emphasizes the importance of prevention of morbidities, especially CP, to reduce the long-term costs of prematurity.

Epigenetic Biomarkers of Preterm Birth and Its Risk Factors

PubMed Central

Knight, Anna K.; Smith, Alicia K.

2016-01-01

A biomarker is a biological measure predictive of a normal or pathogenic process or response. Biomarkers are often useful for making clinical decisions and determining treatment course. One area where such biomarkers would be particularly useful is in identifying women at risk for preterm delivery and related pregnancy complications. Neonates born preterm have significant morbidity and mortality, both in the perinatal period and throughout the life course, and identifying women at risk of delivering preterm may allow for targeted interventions to prevent or delay preterm birth (PTB). In addition to identifying those at increased risk for preterm birth, biomarkers may be able to distinguish neonates at particular risk for future complications due to modifiable environmental factors, such as maternal smoking or alcohol use during pregnancy. Currently, there are no such biomarkers available, though candidate gene and epigenome-wide association studies have identified DNA methylation differences associated with PTB, its risk factors and its long-term outcomes. Further biomarker development is crucial to reducing the health burden associated with adverse intrauterine conditions and preterm birth, and the results of recent DNA methylation studies may advance that goal. PMID:27089367

The microbiome, parturition, and timing of birth: more questions than answers.

PubMed

Prince, Amanda L; Antony, Kathleen M; Chu, Derrick M; Aagaard, Kjersti M

2014-10-01

The causes of preterm birth are multifactorial, but its association with infection has been well-established. The predominant paradigm describes an ascending infection from the lower genital tract through the cervix and into the presumably sterile fetal membranes and placenta. Thus, an evaluation of the role of the vaginal microbiome in preterm birth is implicated. However, emerging fields of data described in this review suggest that the placenta might not be sterile, even in the absence of clinical infection. We thus propose an additional mechanism for placental colonization and infection: hematogenous spread. When considered in the context of decades of evidence demonstrating a strong risk of recurrence for preterm birth, studies on parturition are ideal for applying the rapidly expanding field of metagenomics and analytic pipelines. The translational implications toward identification of innovative treatments for the prevention of preterm birth are further discussed. In sum, exciting advances in understanding the role of both host and microbiota in parturition and preterm birth are on the horizon. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

INCOME INCONGRUITY, RACE AND PRETERM BIRTH

EPA Science Inventory

Previous research with vital records finds income incongruity associated with adverse birth outcomes. We examined the effects of negative income incongruity (reporting lower household income than the census tract median household income) on preterm birth (PTB <37 weeks completed ...

Racial and ethnic disparities in use of 17-alpha hydroxyprogesterone caproate for prevention of preterm birth.

PubMed

Yee, Lynn M; Liu, Lilly Y; Sakowicz, Allie; Bolden, Janelle R; Miller, Emily S

2016-03-01

Racial/ethnic disparities in preterm birth remain a major public health challenge in the United States. While 17-alpha hydroxyprogesterone caproate (17OHP-C) is recommended for preterm birth prevention in women with a prior preterm birth, non-Hispanic black women continue to experience higher rates of recurrent preterm birth than white women receiving the same treatment. Further investigation of disparities in 17OHP-C use and adherence is warranted. We sought to evaluate whether racial and ethnic disparities exist in the use of and adherence to 17OHP-C within a population of eligible women. This was a retrospective cohort study of women with a prior spontaneous, singleton preterm birth who were eligible for 17OHP-C for preterm birth prevention and received care at a single institution from 2010 through 2014. Associations between self-identified race/ethnicity (non-Hispanic black vs women in all other racial/ethnic groups) and documented counseling about 17OHP-C, receipt of any 17OHP-C, and adherence to 17OHP-C administration were each estimated by bivariable analysis and multivariable logistic regression. Adherence to 17OHP-C was defined as not >1 missed dose, initiation <20 weeks' gestational age, and continuation until 37 weeks or delivery. Of 472 women who were clinically eligible for 17OHP-C, 72% (N = 296) had documented 17OHP-C counseling and 48.9% (N = 229) received 17OHP-C. There were no differences in likelihood of 17OHP-C counseling or receipt of 17OHP-C based on race/ethnicity. While overall 83% (N = 176) of women were adherent to 17OHP-C, only 70% (N = 58) of non-Hispanic black women were adherent, compared to 91% (N = 118) of all other women (P < .001). Non-Hispanic black women had more missed doses (2.4 vs 0.4 doses, P < .001) and later initiation of care (12.0 vs 10.2 weeks, P < .001) than women in other racial/ethnic groups. After adjustment for potential confounders, non-Hispanic black women were significantly less likely to be adherent to 17OHP-C (adjusted odds ratio, 0.16; 95% confidence interval, 0.04-0.65). A significant interaction between non-Hispanic black race/ethnicity and public insurance was identified (adjusted odds ratio, 0.16; 95% confidence interval, 0.05-0.52). In a diverse cohort of women eligible for preterm birth prevention, non-Hispanic black women are at an increased risk of nonadherence to 17OHP-C. Non-Hispanic black women with public insurance are at a particularly increased risk of nonadherence. Copyright © 2016 Elsevier Inc. All rights reserved.

Accounting for treatment by center interaction in sample size determinations and the use of surrogate outcomes in the pessary for the prevention of preterm birth trial: a simulation study.

PubMed

Willan, Andrew R

2016-07-05

The Pessary for the Prevention of Preterm Birth Study (PS3) is an international, multicenter, randomized clinical trial designed to examine the effectiveness of the Arabin pessary in preventing preterm birth in pregnant women with a short cervix. During the design of the study two methodological issues regarding power and sample size were raised. Since treatment in the Standard Arm will vary between centers, it is anticipated that so too will the probability of preterm birth in that arm. This will likely result in a treatment by center interaction, and the issue of how this will affect the sample size requirements was raised. The sample size requirements to examine the effect of the pessary on the baby's clinical outcome was prohibitively high, so the second issue is how best to examine the effect on clinical outcome. The approaches taken to address these issues are presented. Simulation and sensitivity analysis were used to address the sample size issue. The probability of preterm birth in the Standard Arm was assumed to vary between centers following a Beta distribution with a mean of 0.3 and a coefficient of variation of 0.3. To address the second issue a Bayesian decision model is proposed that combines the information regarding the between-treatment difference in the probability of preterm birth from PS3 with the data from the Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study that relate preterm birth and perinatal mortality/morbidity. The approach provides a between-treatment comparison with respect to the probability of a bad clinical outcome. The performance of the approach was assessed using simulation and sensitivity analysis. Accounting for a possible treatment by center interaction increased the sample size from 540 to 700 patients per arm for the base case. The sample size requirements increase with the coefficient of variation and decrease with the number of centers. Under the same assumptions used for determining the sample size requirements, the simulated mean probability that pessary reduces the risk of perinatal mortality/morbidity is 0.98. The simulated mean decreased with coefficient of variation and increased with the number of clinical sites. Employing simulation and sensitivity analysis is a useful approach for determining sample size requirements while accounting for the additional uncertainty due to a treatment by center interaction. Using a surrogate outcome in conjunction with a Bayesian decision model is an efficient way to compare important clinical outcomes in a randomized clinical trial in situations where the direct approach requires a prohibitively high sample size.

Investigation of Metronidazole Use during Pregnancy and Adverse Birth Outcomes

PubMed Central

Koss, Catherine A.; Baras, Dana C.; Lane, Sandra D.; Aubry, Richard; Marcus, Michele; Markowitz, Lauri E.

2012-01-01

To assess whether treatment with metronidazole during pregnancy is associated with preterm birth, low birth weight, or major congenital anomalies, we conducted chart reviews and an analysis of electronic data from a cohort of women delivering at an urban New York State hospital. Of 2,829 singleton/mother pairs, 922 (32.6%) mothers were treated with metronidazole for clinical indications, 348 (12.3%) during the first trimester of pregnancy and 553 (19.5%) in the second or third trimester. There were 333 (11.8%) preterm births, 262 (9.3%) infants of low birth weight, and 52 infants (1.8%) with congenital anomalies. In multivariable analysis, no association was found between metronidazole treatment and preterm birth (odds ratio [OR], 1.02 [95% confidence interval [CI], 0.80 to 1.32]), low birth weight (OR, 1.05 [95% CI, 0.77 to 1.43]), or treatment in the first trimester and congenital anomalies (OR, 0.86 [0.30 to 2.45]). We found no association between metronidazole treatment during the first or later trimesters of pregnancy and preterm birth, low birth weight, or congenital anomalies. PMID:22751543

[Participation of the genital mycoplasmas: Ureaplasma urealyticum and Mycoplasma hominis in the processes of preterm birth].

PubMed

Museva, A; Shopova, E; Dimitrov, A; Nikolov, A

2007-01-01

According to contemporary data Ureaplasma urealiticum and Mycoplasma hominis are considered to be the most frequently isolated causative microorganisms from the amniotic cavity. They cause intrauterine infection on preterm birth. The genital mycoplasma are detected in vaginal smears more than 25% of healthy pregnant women and the reason for their invasion towards the uterine cavity in some cases are still unknown. The aim of this study is to investigate the relation between vaginal mycoplasmal contamination and preterm birth. The observed cases are distributed into 2 groups:--patients with preterm birth--35 pregnant women,--term birth--31 pregnant women. The vaginal secretion was tested with a standard microbiological methods and with specific test mycoplasma detection and quantitative assessment. In the first group in five patients (14.3%) Ur. urealiticum was detected in association with other vaginal pathogens (bacterial vaginosis and GBS). In the term birth group 2 patients were mycoplasma positive (6.5%) and associated Enterococcus and Lactobacillus was found in them. All neonates of the mycoplasma positive mothers had sings of infection and underwent antimicrobial therapy course. The results did not demonstrate statistically significant difference in the incidence of vaginal mycoplasmal presence in preterm and term delivery but shows possible relationship between preterm birth caused by ascending mycoplasmal infection which is in association with other vaginal pathogens.

Multi-level modeling of social factors and preterm delivery in Santiago de Chile

PubMed Central

Kaufman, Jay S; Alonso, Faustino T; Pino, Paulina

2008-01-01

Background Birth before the 37th week of gestation (preterm birth) is an important cause of infant and neonatal mortality, but has been little studied outside of wealthy nations. Chile is an urbanized Latin American nation classified as "middle-income" based on its annual income per capita of about $6000. Methods We studied the relations between maternal social status and neighborhood social status on risk of preterm delivery in this setting using multilevel regression analyses of vital statistics data linked to geocoded decennial census data. The analytic data set included 56,970 births from 2004 in the metropolitan region of Santiago, which constitutes about 70% of all births in the study area and about 25% of all births in Chile that year. Dimensionality of census data was reduced using principal components analysis, with regression scoring to create a single index of community socioeconomic advantage. This was modeled along with years of maternal education in order to predict preterm birth and preterm low birthweight. Results Births in Santiago displayed an advantaged pattern of preterm risk, with only 6.4% of births delivering before 37 weeks. Associations were observed between risk of outcomes and individual and neighborhood factors, but the magnitudes of these associations were much more modest than reported in North America. Conclusion While several potential explanations for this relatively flat social gradient might be considered, one possibility is that Chile's egalitarian approach to universal prenatal care may have reduced social inequalities in these reproductive outcomes. PMID:18842145

Pushing the boundaries of viability: the economic impact of extreme preterm birth.

PubMed

Petrou, Stavros; Henderson, Jane; Bracewell, Melanie; Hockley, Christine; Wolke, Dieter; Marlow, Neil

2006-02-01

Previous assessments of the economic impact of preterm birth focussed on short term health service costs across the broad spectrum of prematurity. To estimate the societal costs of extreme preterm birth during the sixth year after birth. Unit costs were applied to estimates of health, social and broader resource use made by 241 children born at 20 through 25 completed weeks of gestation in the United Kingdom and Republic of Ireland and a comparison group of 160 children born at full term. Societal costs per child during the sixth year after birth were estimated and subjected to a rigorous sensitivity analysis. The effects of gestational age at birth on annual societal costs were analysed, first in a simple linear regression and then in a multiple linear regression. Mean societal costs over the 12 month period were 9541 pounds sterling (standard deviation 11,678 pounds sterling) for the extreme preterm group and 3883 pounds sterling (1098 pounds sterling) for the term group, generating a mean cost difference of 5658 pounds sterling (bootstrap 95% confidence interval: 4203 pounds sterling, 7256 pounds sterling) that was statistically significant (P<0.001). After adjustment for clinical and sociodemographic covariates, sex-specific extreme preterm birth was a strong predictor of high societal costs. The results of this study should facilitate the effective planning of services and may be used to inform the development of future economic evaluations of interventions aimed at preventing extreme preterm birth or alleviating its effects.

EXPOSURE TO AREA-LEVEL PRETERM BIRTH DISPARITY AND EFFECTS ON BIRTH OUTCOMES

EPA Science Inventory

Black–white disparity in preterm birth (PTB) is persistent and not explained by individual factors. Given that exposure to inequality is associated with increased risk of adverse health, we examined PTB risk (birth <37 weeks gestational age) explained by living in U.S. census tra...

The impact of preterm birth on participation in childhood occupation.

PubMed

Killeen, Hazel; Shiel, Agnes; Law, Mary; Segurado, Ricardo; O'Donovan, Donough

2015-03-01

Outcome studies of premature babies have focused their assessments predominately on neurodevelopmental impairments without relating these deficits to the impact they have on a child's everyday life. This study aims to determine whether very 'preterm birth alone' impacts on a child's ability to participate in and carry out childhood activities. Forty-four former premature infants between 6 months and 5 years 6 months, born in Galway University Hospital, Ireland, without physical or intellectual disability, were compared with 51 age-matched term-born infants. Study infants had an average gestation of 29 weeks and birth weight of 1,145 g. Functional skills were assessed using the Adaptive Behavior Assessment Scale-II and the Assessment of Preschool Children's Participation. Premature infants had significantly lower mean scores in overall adaptive behaviour compared to term infants, regardless of whether chronological (difference = 13.6, 95% (CI) = [8.2, 19.1]) or corrected (difference = 6.6, 95% CI = [1.4, 11.8]) age was used. Premature infants had lower mean scores in conceptual, social and practical skills, but no difference was found between the groups in intensity or diversity of participation. Premature infants had significantly lower scores in adaptive behaviour than term infants. This measurable effect of preterm birth on 'childhood occupations' merits further investigation.

Relationships between air pollution and preterm birth in California.

PubMed

Huynh, Mary; Woodruff, Tracey J; Parker, Jennifer D; Schoendorf, Kenneth C

2006-11-01

Air pollution from vehicular emissions and other combustion sources is related to cardiovascular and respiratory outcomes. However, few studies have investigated the relationship between air pollution and preterm birth, a primary cause of infant mortality and morbidity. This analysis examined the effect of fine particulate matter (PM(2.5)) and carbon monoxide (CO) on preterm birth in a matched case-control study. PM(2.5) and CO monitoring data from the California Air Resources Board were linked to California birth certificate data for singletons born in 1999-2000. Each birth was mapped to the closest PM monitor within 5 miles of the home address. County-level CO measures were utilised to increase sample size and maintain a representative population. After exclusion of implausible birthweight-gestation combinations, preterm birth was defined as birth occurring between 24 and 36 weeks' gestation. Each of the 10 673 preterm cases was matched to three controls of term (39-44 weeks) gestation with a similar date of last menstrual period. Based on the case's gestational age, CO and PM(2.5) exposures were calculated for total pregnancy, first month of pregnancy, and last 2 weeks of pregnancy. Exposures were divided into quartiles; the lowest quartile was the reference. Because of the matched design, conditional logistic regression was used to adjust for maternal race/ethnicity, age, parity, marital status and education. High total pregnancy PM(2.5) exposure was associated with a small effect on preterm birth, after adjustment for maternal factors (adjusted odds ratio [AOR] = 1.15, [95% CI 1.07, 1.24]). The odds ratio did not change after adjustment for CO. Results were similar for PM(2.5) exposure during the first month of pregnancy (AOR = 1.21, 95% CI [1.12, 1.30]) and the last 2 weeks of pregnancy (AOR = 1.17, 95% CI [1.09, 1.27]). Conversely, CO exposure at any time during pregnancy was not associated with preterm birth (AORs from 0.95 to 1.00). Maternal exposure to PM(2.5), but not CO, is associated with preterm birth. This analysis did not show differences by timing of exposure, although more detailed examination may be needed.

Prolonged progesterone administration is associated with less frequent cervicovaginal colonization by Ureaplasma urealyticum during pregnancy - Results of a pilot study.

PubMed

Koucký, Michal; Malíčková, Karin; Cindrová-Davies, Tereza; Smíšek, Jan; Vráblíková, Hana; Černý, Andrej; Šimják, Patrik; Slováčková, Miroslava; Pařízek, Antonín; Zima, Tomáš

2016-08-01

Preterm birth is a leading cause of perinatal mortality and morbidity. Heavy cervicovaginal Ureaplasma colonization is thought to play a role in the pathogenesis of preterm birth. The administration of vaginal progesterone has been shown to reduce the incidence of preterm birth in women with short cervical length. Steroid hormones seem to modulate the presence of microorganisms in the vagina. The aim of this study was to assess whether the treatment with vaginal progesterone could reduce the incidence of preterm birth and cervicovaginal colonization by Ureaplasma urealyticum in a cohort of pregnant women with threatened preterm labor. A cohort of 63 females who presented with regular contractions and/or short cervical length between 24-32 weeks of gestation were recruited into a prospective study. 70% of patients had been treated with vaginal progesterone prior to recruitment and these patients continued with the treatment until birth. All patients were tested for the presence of cervicovaginal Ureaplasma urealyticum colonization at admission. The primary endpoint was preterm birth before 37 weeks. The incidence of preterm delivery was significantly increased in patients who tested positive for Ureaplasma urealyticum. Prolonged vaginal progesterone administration was associated with less frequent cervicovaginal colonization by U. urealyticum. Cervicovaginal colonization by U. urealyticum and absence of progesterone treatment were identified as two independent risk factors for preterm delivery. Our results demonstrate the beneficial effects of progesterone administration in reducing the incidence of cervicovaginal colonization by Ureaplasma urealyticum. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Gestational age and adolescent mental health: evidence from Hong Kong's 'Children of 1997' birth cohort.

PubMed

Wang, Hui; Leung, Gabriel M; Lam, H S; Schooling, C Mary

2015-09-01

Preterm, and more recently early term, birth has been identified as a risk factor for poor health. Whether the sequelae of late preterm or early term birth extends to poor mental health and well-being in adolescence is unclear and has not been systematically assessed. Linear regression was used to assess the adjusted associations of gestational age (very/moderate preterm (<34 weeks, n=85), late preterm (34-36 weeks, n=305), early term (37-38 weeks, n=2228), full term (39-40 weeks, n=4018), late term (41 weeks, n=809), post-term (≥42 weeks, n=213)) with self-reported self-esteem at ∼11 years (n=6935), parent-reported Rutter score assessing the common emotional and behavioural problems at ∼7 years (n=6292) and ∼11 years (n=5596) and self-reported depressive symptoms at ∼13 years (n=5795) in a population-representative Hong Kong Chinese birth cohort 'Children of 1997' where gestational age has little social patterning. Very/moderate preterm birth was associated with higher Rutter subscore for hyperactivity (ß coefficients 0.5, 95% CI 0.01 to 1.00) at ∼7 years but not at ∼11 years, adjusted for sex, age, socio-economic position, parents' age at birth, birth order and secondhand smoke exposure. Similarly adjusted, late preterm, early term, late term and post-term birth were not associated with self-esteem or depressive symptoms. In a population-representative birth cohort from a non-Western-developed setting, gestational age had few associations with mental health and well-being in adolescence, whereas very preterm birth was specifically associated with hyperactivity in childhood. Inconsistencies with studies from Western settings suggest setting specific unmeasured confounding may underlie any observed associations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Treatment of abnormal vaginal flora in early pregnancy with clindamycin for the prevention of spontaneous preterm birth: a systematic review and metaanalysis

PubMed Central

Lamont, Ronald F.; Nhan-Chang, Chia-Ling; Sobel, Jack D.; Workowski, Kimberly; Conde-Agudelo, Agustin; Romero, Roberto

2011-01-01

The purpose of this study was to determine whether the administration of clindamycin to women with abnormal vaginal flora at <22 weeks of gestation reduces the risk of preterm birth and late miscarriage. We conducted a systematic review and metaanalysis of randomized controlled trials of the early administration of clindamycin to women with abnormal vaginal flora at <22 weeks of gestation. Five trials that comprised 2346 women were included. Clindamycin that was administered at <22 weeks of gestation was associated with a significantly reduced risk of preterm birth at <37 weeks of gestation and late miscarriage. There were no overall differences in the risk of preterm birth at <33 weeks of gestation, low birthweight, very low birthweight, admission to neonatal intensive care unit, stillbirth, peripartum infection, and adverse effects. Clindamycin in early pregnancy in women with abnormal vaginal flora reduces the risk of spontaneous preterm birth at <37 weeks of gestation and late miscarriage. There is evidence to justify further randomized controlled trials of clindamycin for the prevention of preterm birth. However, a deeper understanding of the vaginal microbiome, mucosal immunity, and the biology of bacterial vaginosis will be needed to inform the design of such trials. PMID:22071048

Stress, pre-term labour and birth outcomes.

PubMed

MacKey, M C; Williams, C A; Tiller, C M

2000-09-01

Stress, pre-term labour and birth outcomes Preliminary studies have suggested that stress may be associated with the onset, treatment and outcomes of pre-term labour; however, a systematic comparison of the stress of women with and without pre-term labour has not been reported. Therefore, the purpose of this exploratory study was to compare the stress (daily hassles and mood states) and birth outcomes of black and white women who experienced pre-term labour (PTL) during pregnancy with those who did not. The convenience sample consisted of 35 pregnant women hospitalized in 1996-1997 for the treatment of PTL (24-35 weeks gestation) and 35 controls matched on age, race, parity, gestational age and method of hospital payment. Women in the PTL group had significantly higher tension-anxiety and depression-dejection on the Profile of Mood States (POMS), lower mean birthweight and mean gestational age, and a higher percentage of babies born <37 weeks and weighing 2500 g or less. Black women in the PTL group and white women in the control group had significantly higher scores on the fatigue sub-scale of the POMS and the work and future security sub-scales of the Daily Hassles Scale. Women in the PTL group whose babies weighed 2500 g or less had significantly higher scores on the health, inner concern and financial responsibility sub-scales of the Daily Hassles Scale. The findings from this study indicate the need for further exploration of the interaction of race and stress in understanding and preventing PTL and low birthweight and the need to examine the role of social support in preventing pre-term birth after an episode of PTL.

Poor Sleep Quality and Associated Inflammation Predict Preterm Birth: Heightened Risk among African Americans.

PubMed

Blair, Lisa M; Porter, Kyle; Leblebicioglu, Binnaz; Christian, Lisa M

2015-08-01

Poor sleep promotes inflammation. In turn, inflammation is a causal mechanism in term as well as preterm parturition. In the United States, a persistent racial disparity in preterm birth exists, with African Americans showing ∼1.5 times greater risk. This study examined associations among sleep quality, serum proinflammatory cytokines, and length of gestation in a racially diverse sample of 138 pregnant women. Observational. Women completed the Pittsburgh Sleep Quality Index (PSQI) and other psychosocial and behavioral measures during midpregnancy. Serum levels of interleukin (IL)-6, IL-8, IL-1β, and tumor necrosis factor (TNF)-α were determined by high-sensitivity assays. Birth outcomes were determined via medical record review. Among African American women (n = 79), shorter gestation was predicted by poorer overall sleep (rs = -0.35, P = 0.002) as well the following PSQI subscales: subjective sleep quality (rs = -0.34, P = 0.002), sleep latency (rs = -0.27, P = 0.02), and sleep efficiency (rs = -0.27, P = 0.02). African American women with poor sleep quality (PSQI > 5) had 10.2 times the odds of preterm birth compared to those with good sleep quality. In contrast, among European American women (n = 53), gestational length was not significantly predicted by sleep quality (Ps > 0.12). Bootstrapping analyses showed that, among African Americans, IL-8 significantly mediated the association between sleep quality and length of gestation (indirect effect estimate -0.029; 95% confidence interval -0.06, -0.002). The data provide novel evidence that African American women exhibit greater inflammation in response to sleep disturbance than European American women and these effects correspond with length of gestation. Racial differences in susceptibility to sleep induced immune dysregulation may contribute to marked racial disparities in preterm birth. © 2015 Associated Professional Sleep Societies, LLC.

Effect of interpregnancy interval on risk of spontaneous preterm birth in Emirati women, United Arab Emirates.

PubMed Central

Al-Jasmi, Fatima; Al-Mansoor, Fatima; Alsheiba, Aisha; Carter, Anne O.; Carter, Thomas P.; Hossain, M. Moshaddeque

2002-01-01

OBJECTIVE: To investigate whether a short interpregnancy interval is a risk factor for preterm birth in Emirati women, where there is a wide range of interpregnancy intervals and uniformity in potentially confounding factors. METHODS: A case-control design based on medical records was used. A case was defined as a healthy multiparous Emirati woman delivering a healthy singleton spontaneously before 37 weeks of gestation between 1997 and 2000, and a control was defined as the next eligible similar woman delivering after 37 weeks of gestation. Women were excluded if there was no information available about their most recent previous pregnancy or if it had resulted in a multiple or preterm birth. Data collected from charts and delivery room records were analysed using the STATA statistical package. All variables found to be valid, stable and significant by univariate analysis were included in multivariate logistic regression analysis. FINDINGS: There were 128 cases who met the eligibility criteria; 128 controls were selected. Short interpregnancy intervals were significantly associated with case status (P<0.05). The multivariate adjusted odds ratios for the 1st, 2nd, and 4th quartiles of interpregnancy interval compared with the lowest-risk 3rd quartile were 8.2, 5.4, and 2.0 (95% confidence intervals: 3.5-19.2, 2.4-12.6, and 0.9- 4.5 respectively). CONCLUSION: A short interpregnancy interval is a risk factor for spontaneous preterm birth in Emirati women. The magnitude of the risk and the risk gradient between exposure quartiles suggest that the risk factor is causal and that its modification would reduce the risk of preterm birth. PMID:12481208

The effects of maternal depression, anxiety, and perceived stress during pregnancy on preterm birth: A systematic review.

PubMed

Staneva, Aleksandra; Bogossian, Fiona; Pritchard, Margo; Wittkowski, Anja

2015-09-01

Experiencing psychological distress such as depression, anxiety, and/or perceived stress during pregnancy may increase the risk for adverse birth outcomes, including preterm birth. Clarifying the association between exposure and outcome may improve the understanding of risk factors for prematurity and guide future clinical and research practices. The aims of the present review were to outline the evidence on the risk of preterm associated with antenatal depression, anxiety, and stress. Four electronic database searches were conducted to identify quantitative population-based, multi-centre, cohort studies and randomised-controlled trial studies focusing on the association between antenatal depression, anxiety, and stress, and preterm birth published in English between 1980 and 2013. Of 1469 electronically retrieved articles, 39 peer-reviewed studies met the final selection criteria and were included in this review following the PRISMA and MOOSE review guidelines. Information was extracted on study characteristics; depression, anxiety and perceived stress were examined as separate and combined exposures. There is strong evidence that antenatal distress during the pregnancy increases the likelihood of preterm birth. Complex paths of significant interactions between depression, anxiety and stress, risk factors and preterm birth were indicated in both direct and indirect ways. The effects of pregnancy distress were associated with spontaneous but not with medically indicated preterm birth. Health practitioners engaged in providing perinatal care to women, such as obstetricians, midwives, nurses, and mental health specialists need to provide appropriate support to women experiencing psychological distress in order to improve outcomes for both mothers and infants. Copyright © 2015 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

White matter microstructure on diffusion tensor imaging is associated with conventional magnetic resonance imaging findings and cognitive function in adolescents born preterm

PubMed Central

FELDMAN, HEIDI M; LEE, ELIANA S; LOE, IRENE M; YEOM, KRISTEN W; GRILL-SPECTOR, KALANIT; LUNA, BEATRIZ

2013-01-01

AIM Diffusion tensor imaging (DTI) was used to evaluate white matter architecture after preterm birth. The goals were (1) to compare white matter microstructure in two cohorts of preterm- and term-born children; and (2) within preterm groups, to determine if sex, gestational age, birthweight, white matter injury score from conventional magnetic resonance imaging (MRI), or IQ was associated with DTI measures. METHOD Participants (n=121; 66 females, 55 males) were aged 9 to 16 years. They comprised 58 preterm children (site 1, n=25; and site 2, n=33) born at less than 36 weeks’ gestation (mean 29.4wks; birthweight 1289g) and 63 term children (site 1, n=40; site 2, n=23) born at more than 37 weeks’ gestation. DTI was analyzed using tract-based spatial statistics. Diffusion measures were fractional anisotropy, axial, radial, and mean diffusivity. RESULTS In no region of the white matter skeleton was fractional anisotropy lower in the preterm group at either site. Within the preterm groups, fractional anisotropy was significantly associated with white matter injury score, but not sex, gestational age, or birthweight. At site 1, fractional anisotropy was associated with IQ. INTERPRETATION DTI contributes to understanding individual differences after preterm birth but may not differentiate a relatively high-functioning group of preterm children from a matched group of term-born children. PMID:22803787

The Effect of Activity Restriction on Infant's Birth Weight and Gestational Age at Birth: PRAMS Data Analysis.

PubMed

Omar, Abeer

2018-01-01

Activity restriction is extensively prescribed for pregnant women with major comorbidities despite the lack of evidence to support its effectiveness in preventing preterm birth or low birth weight. To determine the moderation effect of home activity restriction for more than a week on infant's birth weight and gestational age at birth for high-risk women with obstetrical and medical comorbidities. A secondary analysis of 2004-2008 New York Pregnancy Risk Assessment Monitoring System was conducted with 1426 high-risk women. High-risk group included 41% of women treated with activity restriction and 59% of those not treated with activity restriction. Women with preterm premature rupture of membrane (PPROM) who were treated with activity restriction had a lower infant birth weight ( b = -202.85, p = ≤.001) and gestational age at birth ( b = -.91, p = ≤.001) than those without activity restriction. However, women with preterm labor and hypertensive disorders of pregnancy who were not treated with activity restriction had lower infant gestational age at birth ( b = -96, p = ≤.01) and ( b = -92, p = ≤.001), respectively, compared to those who were treated with activity restriction. Findings suggest a contrary effect of activity restriction on infants born to women with PPROM, which is a major reason for prescribing activity restriction. The current study results may trigger the need to conduct randomized control trials to determine the effect of severity of activity restriction on maternal and infant outcomes.