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.

Changes in Association between Previous Therapeutic Abortion and Preterm Birth in Scotland, 1980 to 2008: A Historical Cohort Study

PubMed Central

Oliver-Williams, Clare; Fleming, Michael; Monteath, Kirsten; Wood, Angela M.; Smith, Gordon C. S.

2013-01-01

Background Numerous studies have demonstrated that therapeutic termination of pregnancy (abortion) is associated with an increased risk of subsequent preterm birth. However, the literature is inconsistent, and methods of abortion have changed dramatically over the last 30 years. We hypothesized that the association between previous abortion and the risk of preterm first birth changed in Scotland between 1 January 1980 and 31 December 2008. Methods and Findings We studied linked Scottish national databases of births and perinatal deaths. We analysed the risk of preterm birth in relation to the number of previous abortions in 732,719 first births (≥24 wk), adjusting for maternal characteristics. The risk (adjusted odds ratio [95% CI]) of preterm birth was modelled using logistic regression, and associations were expressed for a one-unit increase in the number of previous abortions. Previous abortion was associated with an increased risk of preterm birth (1.12 [1.09–1.16]). When analysed by year of delivery, the association was strongest in 1980–1983 (1.32 [1.21–1.43]), progressively declined between 1984 and 1999, and was no longer apparent in 2000–2003 (0.98 [0.91–1.05]) or 2004–2008 (1.02 [0.95–1.09]). A statistical test for interaction between previous abortion and year was highly statistically significant (p<0.001). Analysis of data for abortions among nulliparous women in Scotland 1992–2008 demonstrated that the proportion that were surgical without use of cervical pre-treatment decreased from 31% to 0.4%, and that the proportion of medical abortions increased from 18% to 68%. Conclusions Previous abortion was a risk factor for spontaneous preterm birth in Scotland in the 1980s and 1990s, but the association progressively weakened and disappeared altogether by 2000. These changes were paralleled by increasing use of medical abortion and cervical pre-treatment prior to surgical abortion. Although it is plausible that the two trends were related, we could not test this directly as the data on the method of prior abortions were not linked to individuals in the cohort. However, we speculate that modernising abortion methods may be an effective long-term strategy to reduce global rates of preterm birth. Please see later in the article for the Editors' Summary PMID:23874161

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

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.

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.

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

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

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

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.

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

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.

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

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.

Changes in association between previous therapeutic abortion and preterm birth in Scotland, 1980 to 2008: a historical cohort study.

PubMed

Oliver-Williams, Clare; Fleming, Michael; Monteath, Kirsten; Wood, Angela M; Smith, Gordon C S

2013-01-01

Numerous studies have demonstrated that therapeutic termination of pregnancy (abortion) is associated with an increased risk of subsequent preterm birth. However, the literature is inconsistent, and methods of abortion have changed dramatically over the last 30 years. We hypothesized that the association between previous abortion and the risk of preterm first birth changed in Scotland between 1 January 1980 and 31 December 2008. We studied linked Scottish national databases of births and perinatal deaths. We analysed the risk of preterm birth in relation to the number of previous abortions in 732,719 first births (≥24 wk), adjusting for maternal characteristics. The risk (adjusted odds ratio [95% CI]) of preterm birth was modelled using logistic regression, and associations were expressed for a one-unit increase in the number of previous abortions. Previous abortion was associated with an increased risk of preterm birth (1.12 [1.09-1.16]). When analysed by year of delivery, the association was strongest in 1980-1983 (1.32 [1.21-1.43]), progressively declined between 1984 and 1999, and was no longer apparent in 2000-2003 (0.98 [0.91-1.05]) or 2004-2008 (1.02 [0.95-1.09]). A statistical test for interaction between previous abortion and year was highly statistically significant (p<0.001). Analysis of data for abortions among nulliparous women in Scotland 1992-2008 demonstrated that the proportion that were surgical without use of cervical pre-treatment decreased from 31% to 0.4%, and that the proportion of medical abortions increased from 18% to 68%. Previous abortion was a risk factor for spontaneous preterm birth in Scotland in the 1980s and 1990s, but the association progressively weakened and disappeared altogether by 2000. These changes were paralleled by increasing use of medical abortion and cervical pre-treatment prior to surgical abortion. Although it is plausible that the two trends were related, we could not test this directly as the data on the method of prior abortions were not linked to individuals in the cohort. However, we speculate that modernising abortion methods may be an effective long-term strategy to reduce global rates of preterm birth.

Preterm birth and maternal country of birth in a French district with a multiethnic population.

PubMed

Zeitlin, J; Bucourt, M; Rivera, L; Topuz, B; Papiernik, E

2004-08-01

This analysis explores the association between preterm birth and maternal country of birth in a French district with a multiethnic population. Prospective observational study. District of Seine-Saint-Denis in France 48,746 singleton live births from a population-based birth register between October 1998 and December 2000. We compare preterm birth rates by mother's country of birth controlling for demographic and obstetric factors as well as insurance coverage and timing of initiation of antenatal care. Overall preterm birth rates and preterm birth rates by timing of delivery (<33 weeks versus 33-36 weeks of gestation), mode of onset (spontaneous or indicated preterm birth) and the presence of hypertension in pregnancy. Women born in Northern Africa, Southern Europe and South/East Asia did not have higher preterm birth rates than women born in continental France. Rates were significantly higher for women born in the overseas French districts in the Caribbean and Indian Ocean and Sub-Saharan Africa. Excess risk was greatest for early preterm births, medically indicated births and preterm births associated with hypertension. Patterns of preterm birth with relation to timing, mode of onset and medical complications among of Afro-Caribbean origin should be confirmed in future research.

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.

Mediation of the Relationship between Maternal Phthalate Exposure and Preterm Birth by Oxidative Stress with Repeated Measurements across Pregnancy.

PubMed

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

2017-03-01

Mediation analysis is useful for understanding mechanisms and has been used minimally in the study of the environment and disease. We examined mediation of the association between phthalate exposure during pregnancy and preterm birth by oxidative stress. This nested case-control study of preterm birth ( n = 130 cases, 352 controls) included women who delivered in Boston, Massachusestts, from 2006 through 2008. Phthalate metabolites and 8-isoprostane, an oxidative stress biomarker, were measured in urine from three visits in pregnancy. We applied four counterfactual mediation methods: method 1, utilizing exposure and mediator averages; method 2, using averages but allowing for an exposure-mediator interaction; method 3, incorporating longitudinal measurements of the exposure and mediator; and method 4, using longitudinal measurements and allowing for an exposure-mediator interaction. We observed mediation of the associations between phthalate metabolites and all preterm birth by 8-isoprostane, with the greatest estimated proportion mediated observed for spontaneous preterm births specifically. Fully utilizing repeated measures of the exposure and mediator improved precision of indirect (i.e., mediated) effect estimates, and including an exposure-mediator interaction increased the estimated proportion mediated. For example, for mono(2-ethyl-carboxy-propyl) phthalate (MECPP), a metabolite of di(2-ethylhexyl) phthalate (DEHP), the percent of the total effect mediated by 8-isoprostane increased from 47% to 60% with inclusion of an exposure-mediator interaction term, in reference to a total adjusted odds ratio of 1.67 or 1.48, respectively. This demonstrates mediation of the phthalate-preterm birth relationship by oxidative stress, and the utility of complex regression models in capturing mediated associations when repeated measures of exposure and mediator are available and an exposure-mediator interaction may exist. Citation: Ferguson KK, Chen YH, VanderWeele TJ, McElrath TF, Meeker JD, Mukherjee B. 2017. Mediation of the relationship between maternal phthalate exposure and preterm birth by oxidative stress with repeated measurements across pregnancy. Environ Health Perspect 125:488-494; http://dx.doi.org/10.1289/EHP282.

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.

The association between major birth defects and preterm birth.

PubMed

Honein, Margaret A; Kirby, Russell S; Meyer, Robert E; Xing, Jian; Skerrette, Nyasha I; Yuskiv, Nataliya; Marengo, Lisa; Petrini, Joann R; Davidoff, Michael J; Mai, Cara T; Druschel, Charlotte M; Viner-Brown, Samara; Sever, Lowell E

2009-03-01

To evaluate the association between preterm birth and major birth defects by maternal and infant characteristics and specific types of birth defects. We pooled data for 1995-2000 from 13 states with population-based birth defects surveillance systems, representing about 30% of all U.S. births. Analyses were limited to singleton, live births from 24-44 weeks gestational age. Overall, birth defects were more than twice as common among preterm births (24-36 weeks) compared with term births (37-41 weeks gestation) (prevalence ratio [PR] = 2.65, 95% confidence interval [CI] 2.62-2.68), and approximately 8% of preterm births had a birth defect. Birth defects were over five times more likely among very preterm births (24-31 weeks gestation) compared with term births (PR = 5.25, 95% CI 5.15-5.35), with about 16% of very preterm births having a birth defect. Defects most strongly associated with very preterm birth included central nervous system defects (PR = 16.23, 95% CI 15.49-17.00) and cardiovascular defects (PR = 9.29, 95% CI 9.03-9.56). Birth defects contribute to the occurrence of preterm birth. Research to identify shared causal pathways and risk factors could suggest appropriate interventions to reduce both preterm birth and birth defects.

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

Amniotic Fluid Eicosanoids in Preterm and Term Births: Effects of Risk Factors for Spontaneous Preterm Labor

PubMed Central

Menon, Ramkumar; Fortunato, Stephen J.; Milne, Ginger L.; Brou, Lina; Carnevale, Claudine; Sanchez, Stephanie C.; Hubbard, Leah; Lappas, Martha; Drobek, Cayce Owens; Taylor, Robert N.

2012-01-01

OBJECTIVE To evaluate amniotic fluid (AF) arachidonic acid metabolites using enzymatic and nonenzymatic (lipid peroxidation) pathways in spontaneous preterm birth and term births, and to estimate whether prostanoid concentrations correlate with risk factors (race, cigarette smoking, and microbial invasion of amniotic cavity) associated with preterm birth. METHODS In a case-control study, AF was collected at the time of labor or during cesarean delivery. AF samples were subjected to gas chromatography, negative ion chemical ionization, and mass spectrometry for prostaglandin (PG)E2, PGF2α, and PGD2, 6-keto-PGF1α (6-KPGF1α, thromboxane (TXB2), and F2-isoprostane (F2-IsoP). Primary analysis examined differences between prostanoid concentrations in preterm birth (n=133) compared with term births (n=189). Secondary stratified analyses (by race, cigarette smoking and microbial invasion of amniotic cavity) compared eicosanoid concentrations in three epidemiological risk factors. RESULTS AF F2-IsoP, PGE2, and PGD2 were significantly higher at term than in PTB, whereas PGF2 α was higher in PTB 6-KPGF1α and TXB2 concentrations were not different. Data stratified by race (African American or Caucasian) showed no significant disparity among prostanoid concentrations. Regardless of gestational age status, F2-IsoP was threefold higher in smokers, and other eicosanoids were also higher in smokers compared to non-smokers. Preterm birth with microbial invasion of amniotic cavity had significantly higher F2-IsoP compared to preterm birth without microbial invasion of amniotic cavity. CONCLUSIONS Most AF eicosanoid concentrations (F2-isoP PGE2 and PGD2), are higher at term than in preterm birth. The only AF eicosanoid that is not higher at term is PGF2α. PMID:21691170

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.

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.

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

The Canadian Preterm Birth Network: a study protocol for improving outcomes for preterm infants and their families

PubMed Central

Shah, Prakesh S.; McDonald, Sarah D.; Barrett, Jon; Synnes, Anne; Robson, Kate; Foster, Jonathan; Pasquier, Jean-Charles; Joseph, K.S.; Piedboeuf, Bruno; Lacaze-Masmonteil, Thierry; O'Brien, Karel; Shivananda, Sandesh; Chaillet, Nils; Pechlivanoglou, Petros

2018-01-01

Background: Preterm birth (birth before 37 wk of gestation) occurs in about 8% of pregnancies in Canada and is associated with high mortality and morbidity rates that substantially affect infants, their families and the health care system. Our overall goal is to create a transdisciplinary platform, the Canadian Preterm Birth Network (CPTBN), where investigators, stakeholders and families will work together to improve childhood outcomes of preterm neonates. Methods: Our national cohort will include 24 maternal-fetal/obstetrical units, 31 neonatal intensive care units and 26 neonatal follow-up programs across Canada with planned linkages to provincial health information systems. Three broad clusters of projects will be undertaken. Cluster 1 will focus on quality-improvement efforts that use the Evidence-based Practice for Improving Quality method to evaluate information from the CPTBN database and review the current literature, then identify potentially better health care practices and implement identified strategies. Cluster 2 will assess the impact of current practices and practice changes in maternal, perinatal and neonatal care on maternal, neonatal and neurodevelopmental outcomes. Cluster 3 will evaluate the effect of preterm birth on babies, their families and the health care system by integrating CPTBN data, parent feedback, and national and provincial database information in order to identify areas where more parental support is needed, and also generate robust estimates of resource use, cost and cost-effectiveness around preterm neonatal care. Interpretation: These collaborative efforts will create a flexible, transdisciplinary, evaluable and informative research and quality-improvement platform that supports programs, projects and partnerships focused on improving outcomes of preterm neonates. PMID:29348260

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.

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

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.

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

Preterm birth and multiple pregnancy in European countries participating in the PERISTAT project.

PubMed

Blondel, B; Macfarlane, A; Gissler, M; Breart, G; Zeitlin, J

2006-05-01

To compare rates of preterm birth among multiple births in European countries, to estimate their contribution to overall preterm birth rates and to explore factors which could explain differences between preterm birth rates. Analyses of data from vital statistics, birth registers or national samples of births. Eleven member states of the European Union. All live births or representative samples of births at national or regional level for the year 2000 or most recent year. Description of rates of preterm birth before 37 and 32 weeks, estimation of population attributable risks (PAR), study of associations between preterm birth rates in multiples and singletons and nonspontaneous labour using Spearman's rank correlation coefficient. Preterm birth rates, PAR, proportions of deliveries with nonspontaneous onset (caesarean sections before labour or induction of labour). The proportion of multiple births before 37 weeks varied from 68.4% in Austria to 42.2% in the Republic of Ireland. In half of the countries, over 20% of all preterm births were attributable to multiple births. A strong association was found between the proportions of births before 37 weeks among multiple and singleton births (r= 0.81; P < 0.001). An association was observed between the rates of preterm birth and the proportions of deliveries with nonspontaneous onset among twins. Wide variations in rates of preterm births and deliveries with nonspontaneous onset were found between countries, suggesting marked differences in clinical practice which could have long-term implications for the health of children from multiple births.

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.

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.

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

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.

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.

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.

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

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.

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.

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

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

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.

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.

The effect of health compromising behaviors on preterm births.

PubMed

Dew, Paul C; Guillory, V James; Okah, Felix A; Cai, Jinwen; Hoff, Gerald L

2007-05-01

The objective of our study was to determine whether there were combined effects of smoking, alcohol, and illicit drug use during pregnancy on the frequency of preterm births, and if so, the magnitude of the association after adjusting for confounding factors. We conducted a retrospective cohort study of singleton live births in Kansas City, Missouri from 1990-2002. We defined health compromising behaviors as the use of cigarettes, alcohol, and illicit drugs. The effect of these behaviors on preterm births was considered for each substance individually, and in combination. The rates of preterm births for these groups were calculated. Using logistic regression, adjusted odds ratios were used to estimate the relative risk of preterm births among these groups. Over 13% of infants born to women who smoked were preterm, compared to 9.6% for non-smokers. Of infants born to women who reported alcohol use, 17.3% were preterm compared to 10.1% for non-drinkers. Smoking and alcohol use in combination was associated with 18.0% preterm births, while alcohol and drug use in combination was associated with 20.8% preterm births. The use of all three substances was associated with 31.4% preterm births. Women who engaged in health compromising behaviors during pregnancy showed an increased proportion of preterm births compared to those who did not. There is significant interaction between these behaviors leading to higher rates of preterm births than predicted by their additive effects. To decrease preterm births, we must deal with the effects of smoking, drinking, and drug use simultaneously.

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

[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.

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.

Bacterial Hyaluronidase Promotes Ascending GBS Infection and Preterm Birth

PubMed Central

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

2016-01-01

ABSTRACT 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. PMID:27353757

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

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.

Explaining the low risk of preterm birth among arab americans in the United States: an analysis of 617451 births.

PubMed

El-Sayed, Abdulrahman M; Galea, Sandro

2009-03-01

Arab Americans have a lower risk for preterm birth than white Americans. We assessed factors that may contribute to the association between ethnicity and preterm birth risk in Michigan, the state with the largest concentration of Arab Americans in the United States. Factors assessed as potential contributors to the ethnicity/preterm birth risk association were maternal age, parity, education, marital status, tobacco use, and maternal birthplace. Data were collected about all births in Michigan between 2000 and 2005. Stratified analyses, trivariate analyses, and manual stepwise logistic regression model building were used to assess potential contributors to the ethnicity/preterm birth risk association. Arab ethnicity was associated with lower preterm birth risk compared with non-Arab white subjects in the unadjusted model. Maternal birthplace inside or outside the United States explained 0.17 of the difference in preterm birth risk between Arab ethnicity and non-Arab white mothers; ethnic differences in marital status and tobacco use explained less of the observed ethnic difference in preterm birth risk. In the final model adjusted for all explanatory variables, Arab ethnicity was no longer associated with preterm birth risk. Maternal birthplace, marital status, and tobacco use may contribute to the preterm birth risk difference between Arab ethnicity and non-Arab white mothers. Additional work is needed to consider the mechanisms relating factors such as maternal birthplace and marital status to ethnic differences in preterm birth risk.

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

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.

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

Cervical collagen imaging for determining preterm labor risks using a colposcope with full Mueller matrix capability

NASA Astrophysics Data System (ADS)

Stoff, Susan; Chue-Sang, Joseph; Holness, Nola A.; Gandjbakhche, Amir; Chernomordik, Viktor; Ramella-Roman, Jessica

2016-02-01

Preterm birth is a worldwide health issue, as the number one cause of infant mortality and neurological disorders. Although affecting nearly 10% of all births, an accurate, reliable diagnostic method for preterm birth has, yet, to be developed. The primary constituent of the cervix, collagen, provides the structural support and mechanical strength to maintain cervical closure, through specific organization, during fetal gestation. As pregnancy progresses, the disorganization of the cervical collagen occurs to allow eventual cervical pliability so the baby can be birthed through the cervical opening. This disorganization of collagen affects the mechanical properties of the cervix and, if the changes occur prematurely, may be a significant factor leading to preterm birth. The organization of collagen can be analyzed through the use of Mueller Matrix Polarimetric imaging of the characteristic birefringence of collagen. In this research, we have built a full Mueller Matrix Polarimetry attachment to a standard colposcope to enable imaging of human cervixes during standard prenatal exams at various stages of fetal gestation. Analysis of the polarimetric images provides information of quantity and organization of cervical collagen at specific gestational stages of pregnancy. This quantitative information may provide an indication of risk of preterm birth.

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

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

Maternal Resolution of Grief After Preterm Birth: Implications for Infant Attachment Security

PubMed Central

Clements, Melissa; Poehlmann, Julie

2011-01-01

OBJECTIVE: This study explored the association between mothers' unresolved grief regarding their infant's preterm birth and infant-mother attachment security. We hypothesized that mothers with unresolved grief would be more likely to have insecurely attached infants at 16 months and that this association would be partially mediated by maternal interaction quality. METHODS: This longitudinal study focused on 74 preterm infants (age of <36 weeks) and their mothers who were part of a larger study of high-risk infants. The present analysis included assessment of neonatal and socioeconomic risks at NICU discharge; maternal depression, Reaction to Preterm Birth Interview findings, and quality of parenting at a postterm age of 9 months; and infant-mother attachment at postterm age of 16 months. Associations among findings of grief resolution with the Reaction to Preterm Birth Interview, quality of parenting interactions, and attachment security were explored by using relative risk ratios and logistic and multivariate regression models. RESULTS: The relative risk of developing insecure attachment when mothers had unresolved grief was 1.59 (95% confidence interval: 1.03–2.44). Controlling for covariates (adjusted odds ratio: 2.94), maternal feelings of resolved grief regarding the preterm birth experience were associated with secure infant-mother attachment at 16 months. Maternal grief resolution and interaction quality were independent predictors of attachment security. CONCLUSION: Maternal grief resolution regarding the experience of preterm birth and the quality of maternal interactions have important implications for emerging attachment security for infants born prematurely. PMID:21242223

Sleep duration, vital exhaustion, and odds of spontaneous preterm birth: a case-control study.

PubMed

Kajeepeta, Sandhya; Sanchez, Sixto E; Gelaye, Bizu; Qiu, Chunfang; Barrios, Yasmin V; Enquobahrie, Daniel A; Williams, Michelle A

2014-09-27

Preterm birth is a leading cause of perinatal morbidity and mortality worldwide, resulting in a pressing need to identify risk factors leading to effective interventions. Limited evidence suggests potential relationships between maternal sleep or vital exhaustion and preterm birth, yet the literature is generally inconclusive. We examined the relationship between maternal sleep duration and vital exhaustion in the first six months of pregnancy and spontaneous (non-medically indicated) preterm birth among 479 Peruvian women who delivered a preterm singleton infant (<37 weeks gestation) and 480 term controls who delivered a singleton infant at term (≥37 weeks gestation). Maternal nightly sleep and reports of vital exhaustion were ascertained through in-person interviews. Spontaneous preterm birth cases were further categorized as those following either spontaneous preterm labor or preterm premature rupture of membranes. In addition, cases were categorized as very (<32 weeks), moderate (32-33 weeks), and late (34- <37 weeks) preterm birth for additional analyses. Logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs). After adjusting for confounders, we found that short sleep duration (≤6 hours) was significantly associated with preterm birth (aOR = 1.56; 95% CI 1.11-2.19) compared to 7-8 hours of sleep. Vital exhaustion was also associated with increased odds of preterm birth (aOR = 2.41; 95% CI 1.79-3.23) compared to no exhaustion (Ptrend <0.001). These associations remained significant for spontaneous preterm labor and preterm premature rupture of membranes. We also found evidence of joint effects of sleep duration and vital exhaustion on the odds of spontaneous preterm birth. The results of this case-control study suggest maternal sleep duration, particularly short sleep duration, and vital exhaustion may be risk factors for spontaneous preterm birth. These findings call for increased clinical attention to maternal sleep and the study of potential intervention strategies to improve sleep in early pregnancy with the aim of decreasing risk of preterm birth.

Obstetric History and Likelihood of Preterm Birth of Twins.

PubMed

Easter, Sarah Rae; Little, Sarah E; Robinson, Julian N; Mendez-Figueroa, Hector; Chauhan, Suneet P

2018-01-05

 The objective of this study was to investigate the relationship between preterm birth in a prior pregnancy and preterm birth in a twin pregnancy.  We performed a secondary analysis of a randomized controlled trial evaluating 17-α-hydroxyprogesterone caproate in twins. Women were classified as nulliparous, multiparous with a prior term birth, or multiparous with a prior preterm birth. We used logistic regression to examine the odds of spontaneous preterm birth of twins before 35 weeks according to past obstetric history.  Of the 653 women analyzed, 294 were nulliparas, 310 had a prior term birth, and 49 had a prior preterm birth. Prior preterm birth increased the likelihood of spontaneous delivery before 35 weeks (adjusted odds ratio [aOR]: 2.44, 95% confidence interval [CI]: 1.28-4.66), whereas prior term delivery decreased these odds (aOR: 0.55, 95% CI: 0.38-0.78) in the current twin pregnancy compared with the nulliparous reference group. This translated into a lower odds of composite neonatal morbidity (aOR: 0.38, 95% CI: 0.27-0.53) for women with a prior term delivery.  For women carrying twins, a history of preterm birth increases the odds of spontaneous preterm birth, whereas a prior term birth decreases odds of spontaneous preterm birth and neonatal morbidity for the current twin pregnancy. These results offer risk stratification and reassurance for clinicians. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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.

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.

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.

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.

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.

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.

Neonatal screening for congenital cytomegalovirus infection in preterm and small for gestational age infants.

PubMed

Lorenzoni, F; Lunardi, S; Liumbruno, A; Ferri, G; Madrigali, V; Fiorentini, E; Forli, F; Berrettini, S; Boldrini, A; Ghirri, P

2014-10-01

Congenital cytomegalovirus (CMV) infection affects many organs: reticuloendothelial and central nervous system are particularly involved. Congenital CMV infection is the leading cause of non-genetic sensorineural hearing loss. Hearing impairment can be present at birth or it can occur months or even years after birth. It is as well an important risk factor for antenatal stillbirth, preterm birth and small for gestational age (SGA) condition. For these reasons we should early identify congenital CMV infection investigating at least at risk newborns such as preterm or SGA babies given that a simple and standardized method for a large scale screening program is lacking. In our study, we found an association between congenital CMV infection and preterm births (3.03%) and with SGA condition (3.7%). Consequently, routine CMV urine detection should be performed at least in all babies born before 37 weeks of gestational age and in term SGA newborns.

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.

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.

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.

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.

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

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

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

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.

Critical evaluation of national vital statistics: the case of preterm birth trends in Portugal.

PubMed

Correia, Sofia; Rodrigues, Teresa; Montenegro, Nuno; Barros, Henrique

2015-11-01

Using vital statistics, the Portuguese National Health Plan predicts that 14% of live births will be preterm in 2016. The prediction was based on a preterm birth rise from 5.9% in 2000 to 8.8% in 2009. However, the same source showed an actual decline from 2010 onwards. To assess the plausibility of national preterm birth trends, we aimed to compare the evolution of preterm birth and low birthweight rates between vital statistics and a hospital database. A time-trend analysis (2004-2011) of preterm birth (<37 gestational weeks) and low birthweight (<2500 g) rates was conducted using data on singleton births from the national birth certificates (n = 801,783) and an electronic maternity unit database (n = 21,392). Annual prevalence estimates, ratios of preterm birth:low birthweight and adjusted prevalence ratios were estimated to compare data sources. Although the national prevalence of preterm birth increased from 2004 (5.4%), particularly between 2006 and 2009 (highest rate was 7.5% in 2007), and decreased after 2009 (5.7% in 2011), the prevalence at the maternity unit remained constant. Between 2006 and 2009, preterm birth was almost 1.4 times higher in the national statistics (using the national or the catchment region samples) than in the maternity unit, but no differences were found for low birthweight. Portuguese preterm birth prevalence seems biased between 2006 and 2009, suggesting that early term babies were misclassified as preterm. As civil registration systems are important to support public health decisions, monitoring strategies should be taken to assure good quality data. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

Quantitative fetal fibronectin and cervical length to predict preterm birth in asymptomatic women with previous cervical surgery.

PubMed

Vandermolen, Brooke I; Hezelgrave, Natasha L; Smout, Elizabeth M; Abbott, Danielle S; Seed, Paul T; Shennan, Andrew H

2016-10-01

Quantitative fetal fibronectin testing has demonstrated accuracy for prediction of spontaneous preterm birth in asymptomatic women with a history of preterm birth. Predictive accuracy in women with previous cervical surgery (a potentially different risk mechanism) is not known. We sought to compare the predictive accuracy of cervicovaginal fluid quantitative fetal fibronectin and cervical length testing in asymptomatic women with previous cervical surgery to that in women with 1 previous preterm birth. We conducted a prospective blinded secondary analysis of a larger observational study of cervicovaginal fluid quantitative fetal fibronectin concentration in asymptomatic women measured with a Hologic 10Q system (Hologic, Marlborough, MA). Prediction of spontaneous preterm birth (<30, <34, and <37 weeks) with cervicovaginal fluid quantitative fetal fibronectin concentration in primiparous women who had undergone at least 1 invasive cervical procedure (n = 473) was compared with prediction in women who had previous spontaneous preterm birth, preterm prelabor rupture of membranes, or late miscarriage (n = 821). Relationship with cervical length was explored. The rate of spontaneous preterm birth <34 weeks in the cervical surgery group was 3% compared with 9% in previous spontaneous preterm birth group. Receiver operating characteristic curves comparing quantitative fetal fibronectin for prediction at all 3 gestational end points were comparable between the cervical surgery and previous spontaneous preterm birth groups (34 weeks: area under the curve, 0.78 [95% confidence interval 0.64-0.93] vs 0.71 [95% confidence interval 0.64-0.78]; P = .39). Prediction of spontaneous preterm birth using cervical length compared with quantitative fetal fibronectin for prediction of preterm birth <34 weeks of gestation offered similar prediction (area under the curve, 0.88 [95% confidence interval 0.79-0.96] vs 0.77 [95% confidence interval 0.62-0.92], P = .12 in the cervical surgery group; and 0.77 [95% confidence interval 0.70-0.84] vs 0.74 [95% confidence interval 0.67-0.81], P = .32 in the previous spontaneous preterm birth group). Prediction of spontaneous preterm birth using cervicovaginal fluid quantitative fetal fibronectin in asymptomatic women with cervical surgery is valid, and has comparative accuracy to that in women with a history of spontaneous preterm birth. Copyright © 2016 Elsevier Inc. 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.

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.

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.

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.

[A new German Scale for Assessing Parental Stress after Preterm Birth (PSS:NICU_German/2-scales)].

PubMed

Urlesberger, P; Schienle, A; Pichler, G; Baik, N; Schwaberger, B; Urlesberger, B; Pichler-Stachl, E

2017-04-01

Background Preterm birth is known to be a stressful and anxious situation for parents, which might have long-term impact on the psychological health of mothers and even on the development of their preterm infants. Objective The Parental Stressor Scale: Neonatal Intensive Care Unit (PSS:NICU) was developed to assess parental stress after preterm birth through three subscales [1]. The aim of the present study was to examine the psychometric properties and the dimensionality of the German version of the PSS:NICU to develop a reliable German version of the PSS:NICU. Methods For the development (exploratory factor analysis) 100 parents of preterm infants answered the questionnaire. Results The Sights and Sounds subscale was removed from the German version of the PSS:NICU due to low number of items. NICU_German/2-scales was developed consisting of 2 subscales: Infant Behavior and Appearance (7 Items, Cronbach's α=0,82) and Parental Role Alteration (6 Items, Cronbach's α=0,87). Conclusions The PSS:NICU_German/2-scales is a reliable and economic scale for the assessment of parental stress after preterm birth. © Georg Thieme Verlag KG Stuttgart · New York.

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.

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.

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.

Second trimester serum cortisol and preterm birth: an analysis by timing and subtype.

PubMed

Bandoli, Gretchen; Jelliffe-Pawlowski, Laura L; Feuer, Sky K; Liang, Liang; Oltman, Scott P; Paynter, Randi; Ross, Kharah M; Schetter, Christine Dunkel; Ryckman, Kelli K; Chambers, Christina D

2018-05-24

We hypothesized second trimester serum cortisol would be higher in spontaneous preterm births compared to provider-initiated (previously termed 'medically indicated') preterm births. We used a nested case-control design with a sample of 993 women with live births. Cortisol was measured from serum samples collected as part of routine prenatal screening. We tested whether mean-adjusted cortisol fold-change differed by gestational age at delivery or preterm birth subtype using multivariable linear regression. An inverse association between cortisol and gestational age category (trend p = 0.09) was observed. Among deliveries prior to 37 weeks, the mean-adjusted cortisol fold-change values were highest for preterm premature rupture of the membranes (1.10), followed by premature labor (1.03) and provider-initiated preterm birth (1.01), although they did not differ statistically. Cortisol continues to be of interest as a marker of future preterm birth. Augmentation with additional biomarkers should be explored.

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.

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.

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.

Comparison of gestational dating methods and implications ...

EPA Pesticide Factsheets

OBJECTIVES: Estimating gestational age is usually based on date of last menstrual period (LMP) or clinical estimation (CE); both approaches introduce potential bias. Differences in methods of estimation may lead to misclassificat ion and inconsistencies in risk estimates, particularly if exposure assignment is also gestation-dependent. This paper examines a'what-if' scenario in which alternative methods are used and attempts to elucidate how method choice affects observed results.METHODS: We constructed two 20-week gestational age cohorts of pregnancies between 2000 and 2005 (New Jersey, Pennsylvania, Ohio, USA) using live birth certificates : one defined preterm birth (PTB) status using CE and one using LMP. Within these, we estimated risk for 4 categories of preterm birth (PTBs per 106 pregnancies) and risk differences (RD (95% Cl s)) associated with exposure to particulate matter (PM2. 5).RESULTS: More births were classified preterm using LMP (16%) compared with CE (8%). RD divergences increased between cohorts as exposure period approached delivery. Among births between 28 and 31 weeks, week 7 PM2.5 exposure conveyed RDs of 44 (21 to 67) for CE and 50 (18 to 82) for LMP populations, while week 24 exposure conveyed RDs of 33 (11 to 56) and -20 (-50 to 10), respectively.CONCLUSIONS: Different results from analyses restricted to births with both CE and LMP are most likely due to differences in dating methods rather than selection issues. Results are sensitive t

[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.

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.

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

Socio-economic inequality in preterm birth: a comparative study of the Nordic countries from 1981 to 2000.

PubMed

Petersen, Christina B; Mortensen, Laust H; Morgen, Camilla S; Madsen, Mia; Schnor, Ole; Arntzen, Annett; Gissler, Mika; Cnattingius, Sven; Andersen, Anne-Marie Nybo

2009-01-01

During the 1980s and 1990s, there were large social and structural changes within the Nordic countries. Here we examine time changes in risks of preterm birth by maternal educational attainment in Denmark, Finland, Norway and Sweden. Information on gestational age and maternal socio-economic position was obtained from the NorCHASE database, which includes comparable population-based register data of births from Denmark, Finland, Sweden and Norway from 1981 to 2000. The risks of very preterm birth (<32 gestational weeks) and moderately preterm birth (32-36 gestational weeks) were calculated by maternal educational attainment and analysed in 5-year intervals from 1981 to 2000. Compared with mothers with >12 years of education, mothers with <10 years of education had similarly increased risks of very, and to a lesser extent moderately, preterm birth in all four countries. The educational gradient increased slightly over time in very preterm births in Denmark, while there was a slight narrowing of the gap in Sweden. In moderately preterm births, the educational inequality gap was constant over the study period in Denmark, Norway and Sweden, but narrowed in Finland. The educational gradient in preterm birth remained broadly stable from 1981 to 2000 in all four countries. Consequently, the socio-economic inequalities in preterm birth were not strongly influenced by structural changes during the period.

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.

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.

Estimated reductions in provider-initiated preterm births and hospital length of stay under a universal acetylsalicylic acid prophylaxis strategy: a retrospective cohort study

PubMed Central

Ray, Joel G.; Bartsch, Emily; Park, Alison L.; Shah, Prakesh S.; Dzakpasu, Susie

2017-01-01

Background: Hypertensive disorders, especially preeclampsia, are the leading reason for provider-initiated preterm birth. We estimated how universal acetylsalicylic acid (ASA) prophylaxis might reduce rates of provider-initiated preterm birth associated with preeclampsia and intrauterine growth restriction, which are related conditions. Methods: We performed a cohort study of singleton hospital births in 2013 in Canada, excluding Quebec. We estimated the proportion of term births and provider-initiated preterm births affected by preeclampsia and/or intrauterine growth restriction, and the corresponding mean maternal and newborn hospital length of stay. We projected the potential number of cases reduced and corresponding hospital length of stay if ASA prophylaxis lowered cases of preeclampsia and intrauterine growth restriction by a relative risk reduction (RRR) of 10% (lowest) or 53% (highest), as suggested by randomized clinical trials. Results: Of the 269 303 singleton live births and stillbirths in our cohort, 4495 (1.7%) were provider-initiated preterm births. Of the 4495, 1512 (33.6%) had a diagnosis of preeclampsia and/or intrauterine growth restriction. The mean maternal length of stay was 2.0 (95% confidence interval [CI] 2.0-2.0) days among term births unaffected by either condition and 7.3 (95% CI 6.1-8.6) days among provider-initiated preterm births with both conditions. The corresponding values for mean newborn length of stay were 1.9 (95% CI 1.8-1.9) days and 21.8 (95% CI 17.4-26.2) days. If ASA conferred a 53% RRR against preeclampsia and/or intrauterine growth restriction, 3365 maternal and 11 591 newborn days in hospital would be averted. If ASA conferred a 10% RRR, 635 maternal and 2187 newborn days in hospital would be averted. Interpretation: A universal ASA prophylaxis strategy could substantially reduce the burden of long maternal and newborn hospital stays associated with provider-initiated preterm birth. However, until there is compelling evidence that administration of ASA to all, or most, pregnant women reduces the risk of preeclampsia and/or intrauterine growth restriction, clinicians should continue to follow current clinical practice guidelines. PMID:28646095

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.

Disproportionate cardiac hypertrophy during early postnatal development in infants born preterm.

PubMed

Aye, Christina Y L; Lewandowski, Adam J; Lamata, Pablo; Upton, Ross; Davis, Esther; Ohuma, Eric O; Kenworthy, Yvonne; Boardman, Henry; Wopperer, Samuel; Packham, Alice; Adwani, Satish; McCormick, Kenny; Papageorghiou, Aris T; Leeson, Paul

2017-07-01

BackgroundAdults born very preterm have increased cardiac mass and reduced function. We investigated whether a hypertrophic phenomenon occurs in later preterm infants and when this occurs during early development.MethodsCardiac ultrasound was performed on 392 infants (33% preterm at mean gestation 34±2 weeks). Scans were performed during fetal development in 137, at birth and 3 months of postnatal age in 200, and during both fetal and postnatal development in 55. Cardiac morphology and function was quantified and computational models created to identify geometric changes.ResultsAt birth, preterm offspring had reduced cardiac mass and volume relative to body size with a more globular heart. By 3 months, ventricular shape had normalized but both left and right ventricular mass relative to body size were significantly higher than expected for postmenstrual age (left 57.8±41.9 vs. 27.3±29.4%, P<0.001; right 39.3±38.1 vs. 16.6±40.8, P=0.002). Greater changes were associated with lower gestational age at birth (left P<0.001; right P=0.001).ConclusionPreterm offspring, including those born in late gestation, have a disproportionate increase in ventricular mass from birth up to 3 months of postnatal age. These differences were not present before birth. Early postnatal development may provide a window for interventions relevant to long-term cardiovascular health.

Disproportionate cardiac hypertrophy during early postnatal development in infants born preterm

PubMed Central

Aye, Christina Y L; Lewandowski, Adam J; Lamata, Pablo; Upton, Ross; Davis, Esther; Ohuma, Eric O; Kenworthy, Yvonne; Boardman, Henry; Wopperer, Samuel; Packham, Alice; Adwani, Satish; McCormick, Kenny; Papageorghiou, Aris T; Leeson, Paul

2017-01-01

Background Adults born very preterm have increased cardiac mass and reduced function. We investigated whether a hypertrophic phenomenon occurs in later preterm infants and when this occurs during early development. Methods Cardiac ultrasound was performed on 392 infants (33% preterm at mean gestation 34±2 weeks). Scans were performed during fetal development in 137, at birth and 3 months of postnatal age in 200, and during both fetal and postnatal development in 55. Cardiac morphology and function was quantified and computational models created to identify geometric changes. Results At birth, preterm offspring had reduced cardiac mass and volume relative to body size with a more globular heart. By 3 months, ventricular shape had normalized but both left and right ventricular mass relative to body size were significantly higher than expected for postmenstrual age (left 57.8±41.9 vs. 27.3±29.4%, P<0.001; right 39.3±38.1 vs. 16.6±40.8, P=0.002). Greater changes were associated with lower gestational age at birth (left P<0.001; right P=0.001). Conclusion Preterm offspring, including those born in late gestation, have a disproportionate increase in ventricular mass from birth up to 3 months of postnatal age. These differences were not present before birth. Early postnatal development may provide a window for interventions relevant to long-term cardiovascular health. PMID:28399117

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

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.

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.

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.

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.

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.

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

Comparison of gestational dating methods and implications for exposure-outcome associations: an example with PM2.5 and preterm birth.

PubMed

Rappazzo, Kristen M; Lobdell, Danelle T; Messer, Lynne C; Poole, Charles; Daniels, Julie L

2017-02-01

Estimating gestational age is usually based on date of last menstrual period (LMP) or clinical estimation (CE); both approaches introduce potential bias. Differences in methods of estimation may lead to misclassification and inconsistencies in risk estimates, particularly if exposure assignment is also gestation-dependent. This paper examines a 'what-if' scenario in which alternative methods are used and attempts to elucidate how method choice affects observed results. We constructed two 20-week gestational age cohorts of pregnancies between 2000 and 2005 (New Jersey, Pennsylvania, Ohio, USA) using live birth certificates: one defined preterm birth (PTB) status using CE and one using LMP. Within these, we estimated risk for 4 categories of preterm birth (PTBs per 10 6 pregnancies) and risk differences (RD (95% CIs)) associated with exposure to particulate matter (PM 2.5 ). More births were classified preterm using LMP (16%) compared with CE (8%). RD divergences increased between cohorts as exposure period approached delivery. Among births between 28 and 31 weeks, week 7 PM 2.5 exposure conveyed RDs of 44 (21 to 67) for CE and 50 (18 to 82) for LMP populations, while week 24 exposure conveyed RDs of 33 (11 to 56) and -20 (-50 to 10), respectively. Different results from analyses restricted to births with both CE and LMP are most likely due to differences in dating methods rather than selection issues. Results are sensitive to choice of gestational age estimation, though degree of sensitivity can vary by exposure timing. When both outcome and exposure depend on estimate of gestational age, awareness of nuances in the method used for estimation is critical. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

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

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.

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.

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.

The associations of birth intervals with small-for-gestational-age, preterm, and neonatal and infant mortality: a meta-analysis

PubMed Central

2013-01-01

Background Short and long birth intervals have previously been linked to adverse neonatal outcomes. However, much of the existing literature uses cross-sectional studies, from which deriving causal inference is complex. We examine the association between short/long birth intervals and adverse neonatal outcomes by calculating and meta-analyzing associations using original data from cohort studies conducted in low-and middle-income countries (LMIC). Methods We identified five cohort studies. Adjusted odds ratios (aOR) were calculated for each study, with birth interval as the exposure and small-for-gestational-age (SGA) and/or preterm birth, and neonatal and infant mortality as outcomes. The associations were controlled for potential confounders and meta-analyzed. Results Birth interval of shorter than 18 months had statistically significant increased odds of SGA (pooled aOR: 1.51, 95% CI: 1.31-1.75), preterm (pooled aOR: 1.58, 95% CI: 1.19-2.10) and infant mortality (pooled aOR: 1.83, 95% CI: 1.19-2.81) after controlling for potential confounding factors (reference 36-<60 months). It was also significantly associated with term-SGA, preterm-appropriate-for-gestational-age, and preterm-SGA. Birth interval over 60 months had increased risk of SGA (pooled aOR: 1.22, 95% CI: 1.07-1.39) and term-SGA (pooled aOR: 1.14, 95% CI: 1.03-1.27), but was not associated with other outcomes. Conclusions Birth intervals shorter than 18 months are significantly associated with SGA, preterm birth and death in the first year of life. Lack of access to family planning interventions thus contributes to the burden of adverse birth outcomes and infant mortality in LMICs. Programs and policies must assess ways to provide equitable access to reproductive health interventions to mothers before or soon after delivering a child, but also address underlying socioeconomic factors that may modify and worsen the effect of short intervals. PMID:24564484

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.

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.

Socioeconomic inequalities in very preterm birth rates.

PubMed

Smith, L K; Draper, E S; Manktelow, B N; Dorling, J S; Field, D J

2007-01-01

To investigate the extent of socioeconomic inequalities in the incidence of very preterm birth over the past decade. Ecological study of all 549 618 births in the former Trent health region, UK, from 1 January 1994 to 31 December 2003. All singleton births of 22(+0) to 32(+6) weeks gestation (7 185 births) were identified from population surveys of neonatal services and stillbirths. Poisson regression was used to calculate incidence of very preterm birth (22-32 weeks) and extremely preterm birth (22-28 weeks) by year of birth and decile of deprivation (child poverty section of the Index of Multiple Deprivation). Incidence of very preterm singleton birth rose from 11.9 per 1000 births in 1994 to 13.7 per 1000 births in 2003. Those from the most deprived decile were at nearly twice the risk of very preterm birth compared with those from the least deprived decile, with 16.4 per 1000 births in the most deprived decile compared with 8.5 per 1000 births in the least deprived decile (incidence rate ratio 1.94; 95% CI (1.73 to 2.17)). This deprivation gap remained unchanged throughout the 10-year period. The magnitude of socio-economic inequalities was the same for extremely preterm births (22-28 weeks incidence rate ratio 1.94; 95% CI (1.62 to 2.32)). This large, unique dataset of very preterm births shows wide socio-economic inequalities that persist over time. These findings are likely to have consequences on the burden of long-term morbidity. Our research can assist future healthcare planning, the monitoring of socio-economic inequalities and the targeting of interventions in order to reduce this persistent deprivation gap.

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

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.

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.

Measuring parents' experiences and satisfaction with care during very preterm birth: a questionnaire development study

PubMed Central

Sawyer, A; Rabe, H; Abbott, J; Gyte, G; Duley, L; Ayers, S

2014-01-01

Objective To develop a questionnaire to assess parents' experiences and satisfaction with care during very preterm birth. Design Questionnaire development. Setting Parents whose babies had been cared for at five tertiary neonatal units in England. Population A total of 145 women who gave birth before 32 weeks of gestation, and 85 of their partners. Methods A 30-item questionnaire was developed on the basis of qualitative interviews with parents of very preterm babies, a literature review and discussion with relevant experts. The questionnaire was posted to a second group of parents, and its reliability and validity were explored. Main outcome measures The Preterm Birth Experience and Satisfaction Scale (P-BESS) was correlated with two global questions measuring satisfaction with care during the birth. Internal consistency was measured using Cronbach's α. Results Parents of 458 babies were invited to take part and 147 (32%) responded. Two women and 22 partners were excluded or ineligible, leaving 145 women and 85 partners. Factor analysis produced three clear dimensions: Staff professionalism and empathy, Information and explanations, and Confidence in staff. The total scale and three subscales showed high reliability. Strong positive correlations were found between the questionnaire scales and the two global questions, indicating convergent validity. For women whose partners were present at the birth, a fourth factor was identified ‘Partner Involvement’. Conclusions The P-BESS appears to be a valid measure of satisfaction with care during very preterm birth. PMID:24953082

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.

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.

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.

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.

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.

The associations between birth outcomes and satellite-estimated maternal PM2.5 exposure in Shanghai, China

NASA Astrophysics Data System (ADS)

Xiao, Q.; Liu, Y.; Strickland, M. J.; Chang, H. H.; Kan, H.

2017-12-01

Background: Satellite remote sensing data have been employed for air pollution exposure assessment, with the intent of better characterizing exposure spatio-temproal variations. However, non-random missingness in satellite data may lead to exposure error. Objectives: We explored the differences in health effect estimates due to different exposure metrics, with and without satellite data, when analyzing the associations between maternal PM2.5 exposure and birth outcomes. Methods: We obtained birth registration records of 132,783 singleton live births during 2011-2014 in Shanghai. Trimester-specific and total pregnancy exposures were estimated from satellite PM2.5 predictions with missingness, gap-filled satellite PM2.5 predictions with complete coverage and regional average PM2.5 measurements from monitoring stations. Linear regressions estimated associations between birth weight and maternal PM2.5 exposure. Logistic regressions estimated associations between preterm birth and the first and second trimester exposure. Discrete-time models estimated third trimester and total pregnancy associations with preterm birth. Effect modifications by maternal age and parental education levels were investigated. Results: we observed statistically significant associations between maternal PM2.5 exposure during all exposure windows and adverse birth outcomes. A 10 µg/m3 increase in pregnancy PM2.5 exposure was associated with a 12.85 g (95% CI: 18.44, 7.27) decrease in birth weight for term births, and a 27% (95% CI: 20%, 36%) increase in the risk of preterm birth. Greater effects were observed between first and third trimester exposure and birth weight, as well as between first trimester exposure and preterm birth. Mothers older than 35 years and without college education tended to have higher associations with preterm birth. Conclusions: Gap-filled satellite data derived PM2.5 exposure estimates resulted in reduced exposure error and more precise health effect estimates.

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.

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.

Maternal dental caries and pre-term birth: results from the EPIPAP study.

PubMed

Vergnes, Jean-Noel; Kaminski, Monique; Lelong, Nathalie; Musset, Anne-Marie; Sixou, Michel; Nabet, Cathy

2011-07-01

OBJECTIVE. The aim of this study was to analyse the association between maternal dental caries and pre-term birth (PTB), with a particular focus on the infection-suspected causes of pre-term births. MATERIALS AND METHODS. A secondary analysis was performed on data from the EPIPAP study, a French multi-centre case-control study. Cases were 1107 women giving birth to a singleton live-born infant before 37 weeks of gestation and controls were 1094 women delivering at 37 weeks or more. A sub-group of cases was defined as women with spontaneous labour and/or pre-term premature rupture of membranes (PPROM, n = 620). A full-mouth dental examination was performed after delivery. The main factor of interest was the presence of decay on at least one tooth. RESULTS. Crude associations between presence of tooth decay and PTB or spontaneous PTB/PPROM were significant (OR = 1.21 [1.01-1.45] and OR = 1.25 [1.01-1.55], respectively). After adjustment for two sets of potential confounders (four pre-term birth risk factors and four social characteristics), for periodontitis status and for inter-examiner variability, tooth decay was not significantly associated with either PTB or spontaneous PTB/PPROM (aOR = 1.10 [0.91-1.32] and aOR = 1.14 [0.91-1.42], respectively). CONCLUSIONS. This study failed to demonstrate a significant association between tooth decay and pre-term birth. However, future well-designed studies are needed to further assess the link between dental caries and adverse pregnancy outcomes.

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

Starting the conversation: community perspectives on preterm birth and kangaroo mother care in southern Malawi

PubMed Central

Lydon, Megan; Longwe, Monica; Likomwa, Dyson; Lwesha, Victoria; Chimtembo, Lydia; Donohue, Pamela; Guenther, Tanya; Valsangar, Bina

2018-01-01

Background Despite introduction of Kangaroo Mother Care (KMC) in Malawi over a decade ago, preterm birth remains the leading cause of neonatal mortality. Although KMC is initiated in the health care facility, robust community follow-up is critical for survival and optimal development of preterm and low birth weight infants post-discharge. The objective of this qualitative study was to gain insight into community and health worker understanding, attitudes, beliefs and practices around preterm and low birth weight babies and KMC in Malawi. Methods A total of 152 participants were interviewed in two districts in southern Malawi, Machinga and Thyolo, in April 2015. Focus group discussions (groups = 11, n = 132) were conducted with pregnant women, community members and women who have practiced KMC. In-depth interviews (n = 20) were conducted with fathers who have practiced KMC, community and religious leaders, and health workers. Purposive and snowball sampling were employed to identify participants. Thematic content analysis was conducted. Findings KMC mothers and fathers only learned about KMC and care for preterm newborns after delivery of a child in need of this care. Men typically were not included in KMC counseling due to societal gender roles. Health facilities were the main source of information on KMC, however informal networks among women provided some degree of knowledge exchange. Community leaders were regarded as major facilitators of health information, conveners, key influencers, and policy-makers. Religious leaders were regarded as advocates and emotional support for families with preterm infants. Finally, while many participants initially had negative feelings towards preterm births and KMC, the large majority saw a shift in their perceptions through health counseling, peer modeling, and personal success with KMC. Conclusions The findings offer several opportunities to improve KMC implementation including 1) earlier introduction of KMC to pregnant women and their families that are at-risk for preterm birth, 2) greater involvement of men in KMC counselling, practice and care for preterm infants, and 3) strengthening and defining partnerships with community and religious leaders. Finally, as parental perceptions of preterm infants and KMC improved with successful KMC practice, it is hopeful that KMC itself can positively affect social norms surrounding preterm infants, leading to a virtuous cycle of improved perceptions of preterm infants and increased uptake of KMC. PMID:29904606

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.

The effects of socioeconomic status and indices of physical environment on reduced birth weight and preterm births in Eastern Massachusetts

PubMed Central

Zeka, Ariana; Melly, Steve J; Schwartz, Joel

2008-01-01

Background Air pollution and social characteristics have been shown to affect indicators of health. While use of spatial methods to estimate exposure to air pollution has increased the power to detect effects, questions have been raised about potential for confounding by social factors. Methods A study of singleton births in Eastern Massachusetts was conducted between 1996 and 2002 to examine the association between indicators of traffic, land use, individual and area-based socioeconomic measures (SEM), and birth outcomes (birth weight, small for gestational age and preterm births), in a two-level hierarchical model. Results We found effects of both individual (education, race, prenatal care index) and area-based (median household income) SEM with all birth outcomes. The associations for traffic and land use variables were mainly seen with birth weight, with an exception for an effect of cumulative traffic density on small for gestational age. Race/ethnicity of mother was an important predictor of birth outcomes and a strong confounder for both area-based SEM and indices of physical environment. The effects of traffic and land use differed by level of education and median household income. Conclusion Overall, the findings of the study suggested greater likelihood of reduced birth weight and preterm births among the more socially disadvantaged, and a greater risk of reduced birth weight associated with traffic exposures. Results revealed the importance of controlling simultaneously for SEM and environmental exposures as the way to better understand determinants of health. PMID:19032747

Trends in Racial and Ethnic Disparities in Infant Mortality Rates in the United States, 1989–2006

PubMed Central

Rossen, Lauren M.; Schoendorf, Kenneth C.

2014-01-01

Objectives. We sought to measure overall disparities in pregnancy outcome, incorporating data from the many race and ethnic groups that compose the US population, to improve understanding of how disparities may have changed over time. Methods. We used Birth Cohort Linked Birth–Infant Death Data Files from US Vital Statistics from 1989–1990 and 2005–2006 to examine multigroup indices of racial and ethnic disparities in the overall infant mortality rate (IMR), preterm birth rate, and gestational age–specific IMRs. We calculated selected absolute and relative multigroup disparity metrics weighting subgroups equally and by population size. Results. Overall IMR decreased on the absolute scale, but increased on the population-weighted relative scale. Disparities in the preterm birth rate decreased on both the absolute and relative scales, and across equally weighted and population-weighted indices. Disparities in preterm IMR increased on both the absolute and relative scales. Conclusions. Infant mortality is a common bellwether of general and maternal and child health. Despite significant decreases in disparities in the preterm birth rate, relative disparities in overall and preterm IMRs increased significantly over the past 20 years. PMID:24028239

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

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.

VAGINAL PROGESTERONE VERSUS CERVICAL CERCLAGE FOR THE PREVENTION OF PRETERM BIRTH IN WOMEN WITH A SONOGRAPHIC SHORT CERVIX, SINGLETON GESTATION, AND PREVIOUS PRETERM BIRTH: A SYSTEMATIC REVIEW AND INDIRECT COMPARISON META-ANALYSIS

PubMed Central

CONDE-AGUDELO, Agustin; ROMERO, Roberto; NICOLAIDES, Kypros; CHAIWORAPONGSA, Tinnakorn; O'BRIEN, John M.; CETINGOZ, Elcin; DA FONSECA, Eduardo; CREASY, George; SOMA-PILLAY, Priya; FUSEY, Shalini; CAM, Cetin; ALFIREVIC, Zarko; HASSAN, Sonia S.

2012-01-01

OBJECTIVE No randomized controlled trial has directly compared vaginal progesterone and cervical cerclage for the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous spontaneous preterm birth. We performed an indirect comparison of vaginal progesterone versus cerclage, using placebo/no cerclage as the common comparator. STUDY DESIGN Adjusted indirect meta-analysis of randomized controlled trials. RESULTS Four studies evaluating vaginal progesterone versus placebo (158 patients) and five evaluating cerclage versus no cerclage (504 patients) were included. Both interventions were associated with a statistically significant reduction in the risk of preterm birth <32 weeks of gestation and composite perinatal morbidity and mortality compared with placebo/no cerclage. Adjusted indirect meta-analyses did not show statistically significant differences between vaginal progesterone and cerclage in reducing preterm birth or adverse perinatal outcomes. CONCLUSION Based on state-of-the-art methodology for indirect comparisons, either vaginal progesterone or cerclage are equally efficacious in the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous preterm birth. The selection of the optimal treatment may depend upon adverse events, cost and patient/clinician preferences. PMID:23157855

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

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

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.

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.

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.

17-alpha Hydroxyprogesterone Caproate did not reduce the rate of recurrent preterm birth in a prospective cohort study

PubMed Central

Nelson, David B.; McIntire, Donald D.; McDonald, Jeffrey; Gard, John; Turrichi, Paula; Leveno, Kenneth J.

2017-01-01

Background 17-alpha hydroxyprogesterone caproate for prevention of recurrent preterm birth is recommended for use in the United States. Objective To assess the clinical effectiveness of 17-alpha hydroxyprogesterone caproate to prevent recurrent preterm birth ≤ 35 weeks compared to similar births in our obstetric population prior to the implementation of 17-alpha hydroxyprogesterone caproate. Study Design This was a prospective cohort study of 17-alpha hydroxyprogesterone caproate in our obstetric population. The primary outcome was the recurrence of birth ≤ 35 weeks for the entire study cohort compared to a historical referent rate of 16.8% of recurrent preterm birth in our population. There were three secondary outcomes. First, did 17-alpha hydroxyprogesterone caproate modify a woman’s history of preterm birth when taking into account her prior number and sequence of preterm and term births? Second, was recurrence of preterm birth related to 17-alpha hydroxyprogesterone caproate plasma concentration? Third, was duration of pregnancy modified by 17-alpha hydroxyprogesterone caproate treatment compared to a prior preterm birth? Results Between January 2012 and March 2016, 430 consecutive women with prior births ≤ 35 weeks were treated with 17-alpha hydroxyprogesterone caproate. Nearly two-thirds of the women (N=267) began injections ≤ 18 weeks and 394 (92%) received a scheduled weekly injection within 10 days of reaching 35 weeks or delivery. The overall rate of recurrent preterm birth was 25% (N=106) for the entire cohort compared to the 16.8% expected rate (P = 1.0). The three secondary outcomes were also negative. First, 17-alpha hydroxyprogesterone caproate did not significantly reduce the rates of recurrence regardless of prior preterm birth number or sequence. Second, plasma concentrations of 17-alpha hydroxyprogesterone caproate were not different (P=0.17 at 24 weeks; P=0.38 at 32 weeks) between women delivered ≤ 35 weeks and those delivered later in pregnancy. Third, the mean (± standard deviation) interval in weeks of recurrent preterm birth before 17-alpha hydroxyprogesterone caproate use was 0.4 ± 5.3 weeks and the interval of recurrent preterm birth after 17-alpha hydroxyprogesterone caproate treatment was 0.1 ± 4.7 weeks (P=0.63). A side effect of weekly 17-alpha hydroxyprogesterone caproate injections was an increase in gestational diabetes. Specifically, the rate of gestational diabetes was 13.4% in 17-alpha hydroxyprogesterone caproate treated women compared to 8% in case-matched controls (P=0.001). Conclusions 17-alpha hydroxyprogesterone caproate was ineffective for prevention of recurrent preterm birth and was associated with increased rates of gestational diabetes. PMID:28223163

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

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.

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

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.

Association between maternal nutritional status of pre pregnancy, gestational weight gain and preterm birth.

PubMed

Xinxo, Sonela; Bimbashi, Astrit; Z Kakarriqi, Eduard; Zaimi, Edmond

2013-01-01

Maternal nutritional status of pre pregnancy and gestational weight gain affects the preterm birth. The association between maternal nutritional status of pre pregnancy and preterm birth appears to be complex and varied by studies from different countries, thus this association between the gestational weight gain and preterm birth is more consolidated. The study aims to determine any association between the pre pregnancy maternal nutritional status, gestational weight gain and the preterm birth rate in the Albanian context. In case control study, we analyzed women who have delivered in obstetric institutions in Tirana during the year 2012. Body mass index and gestational weight gain of 150 women who had a preterm delivery were compared with those of 150 matched control women who had a normal delivery regarding the gestation age. The self-reported pre pregnancy weight, height, gestational weight gain, age, education and parity are collected through a structured questioner. The body mass index and gestational weight gain are categorized based on the Institute of Medicine recommendation. The multiple logistic regression is used to measure the association between the nutritional status of pre pregnancy and gestational weight gain and the preterm birth rate. The women which have a underweight status or obese of pre pregnancy are more likely to have a preterm birth compared to the women of a normal pre-pregnancy nutritional status (respectively OR =2.7 and 4.3 p<0.05). Women who do not reach the recommended gestational weight gain are more likely to have a preterm birth compared to the women which reach this weight (OR=1.8 p< 0.05). Maternal nutritional status and gestational weight gain affects the risk for preterm birth. Pre-pregnancy and gestation nutritional assessments should be part of routine prenatal visits.

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.

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.

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.

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.

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 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.

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.

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.

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.

Failure to Thrive in the Term and Preterm Infants of Mothers Depressed in the Postnatal Period: A Population-Based Birth Cohort Study

ERIC Educational Resources Information Center

Drewett, Robert; Blair, Peter; Emmett, Pauline; Emond, Alan

2004-01-01

Aims: To examine the relationship between failure to thrive in preterm and term infants and postnatal depression in their mothers. Method: In a whole population birth cohort of 12,391 infants (excluding those born after term or with major congenital abnormalities) failure to thrive over the first nine months was identified using a conditional…

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.

[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.

Measuring women's cumulative neighborhood deprivation exposure using longitudinally linked vital records: a method for life course MCH research.

PubMed

Kramer, Michael R; Dunlop, Anne L; Hogue, Carol J R

2014-02-01

A life course conceptual framework for MCH research demands new tools for understanding population health and measuring exposures. We propose a method for measuring population-based socio-environmental trajectories for women of reproductive age. We merged maternal longitudinally-linked births to Georgia-resident women from 1994 to 2007 with census economic and social measures using residential geocodes to create woman-centered socio-environmental trajectories. We calculated a woman's neighborhood deprivation index (NDI) at the time of each of her births and, from these, we calculated a cumulative NDI. We fit Loess curves to describe average life course NDI trajectories and binomial regression models to test specific life course theory hypotheses relating cumulative NDI to risk for preterm birth. Of the 1,815,944 total live births, we linked 1,000,437 live births to 413,048 unique women with two or more births. Record linkage had high specificity but relatively low sensitivity which appears non-differential with respect to maternal characteristics. Georgia women on average experienced upward mobility across the life course, although differences by race, early life neighborhood quality, and age at first birth produced differences in cumulative NDI. Adjusted binomial models found evidence for modification of the effect of history of prior preterm birth and advancing age on risk for preterm birth by cumulative NDI. The creation of trajectories from geocoded maternal longitudinally-linked vital records is one method to carry out life course MCH research. We discuss approaches for investigating the impact of truncation of the life course, selection bias from migration, and misclassification of cumulative exposure.

The effect of CenteringPregnancy group prenatal care on preterm birth in a low-income population.

PubMed

Picklesimer, Amy H; Billings, Deborah; Hale, Nathan; Blackhurst, Dawn; Covington-Kolb, Sarah

2012-05-01

The purpose of this study was to evaluate the impact of group prenatal care on rates of preterm birth. We conducted a retrospective cohort study of 316 women in group prenatal care that was compared with 3767 women in traditional prenatal care. Women self-selected participation in group care. Risk factors for preterm birth were similar for group prenatal care vs traditional prenatal care: smoking (16.9% vs 20%; P = .17), sexually transmitted diseases (15.8% vs 13.7%; P = .29), and previous preterm birth (3.2% vs 5.4%; P = .08). Preterm delivery (<37 weeks' gestation) was lower in group care than traditional care (7.9% vs 12.7%; P = .01), as was delivery at <32 weeks' gestation (1.3% vs 3.1%; P = .03). Adjusted odds ratio for preterm birth for participants in group care was 0.53 (95% confidence interval, 0.34-0.81). The racial disparity in preterm birth for black women, relative to white and Hispanic women, was diminished for the women in group care. Among low-risk women, participation in group care improves the rate of preterm birth compared with traditional care, especially among black women. Randomized studies are needed to eliminate selection bias. Copyright © 2012 Mosby, Inc. All rights reserved.

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.

Air Pollution and Preterm Birth in the U.S. State of Georgia (2002–2006): Associations with Concentrations of 11 Ambient Air Pollutants Estimated by Combining Community Multiscale Air Quality Model (CMAQ) Simulations with Stationary Monitor Measurements

PubMed Central

Hao, Hua; Chang, Howard H.; Holmes, Heather A.; Mulholland, James A.; Klein, Mitch; Darrow, Lyndsey A.; Strickland, Matthew J.

2015-01-01

Background: Previous epidemiologic studies suggest associations between preterm birth and ambient air pollution. Objective: We investigated associations between 11 ambient air pollutants, estimated by combining Community Multiscale Air Quality model (CMAQ) simulations with measurements from stationary monitors, and risk of preterm birth (< 37 weeks of gestation) in the U.S. state of Georgia. Methods: Birth records for singleton births ≥ 27 weeks of gestation with complete covariate information and estimated dates of conception between 1 January 2002 and 28 February 2006 were obtained from the Office of Health Indicators for Planning, Georgia Department of Public Health (n = 511,658 births). Daily pollutant concentrations at 12-km resolution were estimated for 11 ambient air pollutants. We used logistic regression with county-level fixed effects to estimate associations between preterm birth and average pollutant concentrations during the first and second trimester. Discrete-time survival models were used to estimate third-trimester and total pregnancy associations. Effect modification was investigated by maternal education, race, census tract poverty level, and county-level urbanicity. Results: Trimester-specific and total pregnancy associations (p < 0.05) were observed for several pollutants. All the traffic-related pollutants (carbon monoxide, nitrogen dioxide, PM2.5 elemental carbon) were associated with preterm birth [e.g., odds ratios for interquartile range increases in carbon monoxide during the first, second, and third trimesters and total pregnancy were 1.005 (95% CI: 1.001, 1.009), 1.007 (95% CI: 1.002, 1.011), 1.010 (95% CI: 1.006, 1.014), and 1.011 (95% CI: 1.006, 1.017)]. Associations tended to be higher for mothers with low educational attainment and African American mothers. Conclusion: Several ambient air pollutants were associated with preterm birth; associations were observed in all exposure windows. Citation: Hao H, Chang HH, Holmes HA, Mulholland JA, Klein M, Darrow LA, Strickland MJ. 2016. Air pollution and preterm birth in the U.S. state of Georgia (2002–2006): associations with concentrations of 11 ambient air pollutants estimated by combining Community Multiscale Air Quality Model (CMAQ) simulations with stationary monitor measurements. Environ Health Perspect 124:875–880; http://dx.doi.org/10.1289/ehp.1409651 PMID:26485731

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.

Global report on preterm birth and stillbirth (3 of 7): evidence for effectiveness of interventions

PubMed Central

2010-01-01

Introduction Interventions directed toward mothers before and during pregnancy and childbirth may help reduce preterm births and stillbirths. Survival of preterm newborns may also be improved with interventions given during these times or soon after birth. This comprehensive review assesses existing interventions for low- and middle-income countries (LMICs). Methods Approximately 2,000 intervention studies were systematically evaluated through December 31, 2008. They addressed preterm birth or low birth weight; stillbirth or perinatal mortality; and management of preterm newborns. Out of 82 identified interventions, 49 were relevant to LMICs and had reasonable amounts of evidence, and therefore selected for in-depth reviews. Each was classified and assessed by the quality of available evidence and its potential to treat or prevent preterm birth and stillbirth. Impacts on other maternal, fetal, newborn or child health outcomes were also considered. Assessments were based on an adaptation of the Grades of Recommendation Assessment, Development and Evaluation criteria. Results Most interventions require additional research to improve the quality of evidence. Others had little evidence of benefit and should be discontinued. The following are supported by moderate- to high-quality evidence and strongly recommended for LMICs: • Two interventions prevent preterm births—smoking cessation and progesterone • Eight interventions prevent stillbirths—balanced protein energy supplementation, screening and treatment of syphilis, intermittant presumptive treatment for malaria during pregnancy, insecticide-treated mosquito nets, birth preparedness, emergency obstetric care, cesarean section for breech presentation, and elective induction for post-term delivery • Eleven interventions improve survival of preterm newborns—prophylactic steroids in preterm labor, antibiotics for PROM, vitamin K supplementation at delivery, case management of neonatal sepsis and pneumonia, delayed cord clamping, room air (vs. 100% oxygen) for resuscitation, hospital-based kangaroo mother care, early breastfeeding, thermal care, and surfactant therapy and application of continued distending pressure to the lungs for respiratory distress syndrome Conclusion The research paradigm for discovery science and intervention development must be balanced to address prevention as well as improve morbidity and mortality in all settings. This review also reveals significant gaps in current knowledge of interventions spanning the continuum of maternal and fetal outcomes, and the critical need to generate further high-quality evidence for promising interventions. PMID:20233384

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...

Predicting School Readiness from Neurodevelopmental Assessments at Age 2 Years after Respiratory Distress Syndrome in Infants Born Preterm

ERIC Educational Resources Information Center

Patrianakos-Hoobler, Athena I.; Msall, Michael E.; Huo, Dezheng; Marks, Jeremy D.; Plesha-Troyke, Susan; Schreiber, Michael D.

2010-01-01

Aim: To determine whether neurodevelopmental outcomes at the age of 2 years accurately predict school readiness in children who survived respiratory distress syndrome after preterm birth. Method: Our cohort included 121 preterm infants who received surfactant and ventilation and were enrolled in a randomized controlled study of inhaled nitric…

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.

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.

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.

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

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.

Preterm Birth and Childhood Wheezing Disorders: A Systematic Review and Meta-Analysis

PubMed Central

Been, Jasper V.; Lugtenberg, Marlies J.; Smets, Eline; van Schayck, Constant P.; Kramer, Boris W.; Mommers, Monique; Sheikh, Aziz

2014-01-01

Background Accumulating evidence implicates early life factors in the aetiology of non-communicable diseases, including asthma/wheezing disorders. We undertook a systematic review investigating risks of asthma/wheezing disorders in children born preterm, including the increasing numbers who, as a result of advances in neonatal care, now survive very preterm birth. Methods and Findings Two reviewers independently searched seven online databases for contemporaneous (1 January 1995–23 September 2013) epidemiological studies investigating the association between preterm birth and asthma/wheezing disorders. Additional studies were identified through reference and citation searches, and contacting international experts. Quality appraisal was undertaken using the Effective Public Health Practice Project instrument. We pooled unadjusted and adjusted effect estimates using random-effects meta-analysis, investigated “dose–response” associations, and undertook subgroup, sensitivity, and meta-regression analyses to assess the robustness of associations. We identified 42 eligible studies from six continents. Twelve were excluded for population overlap, leaving 30 unique studies involving 1,543,639 children. Preterm birth was associated with an increased risk of wheezing disorders in unadjusted (13.7% versus 8.3%; odds ratio [OR] 1.71, 95% CI 1.57–1.87; 26 studies including 1,500,916 children) and adjusted analyses (OR 1.46, 95% CI 1.29–1.65; 17 studies including 874,710 children). The risk was particularly high among children born very preterm (<32 wk gestation; unadjusted: OR 3.00, 95% CI 2.61–3.44; adjusted: OR 2.81, 95% CI 2.55–3.12). Findings were most pronounced for studies with low risk of bias and were consistent across sensitivity analyses. The estimated population-attributable risk of preterm birth for childhood wheezing disorders was ≥3.1%. Key limitations related to the paucity of data from low- and middle-income countries, and risk of residual confounding. Conclusions There is compelling evidence that preterm birth—particularly very preterm birth—increases the risk of asthma. Given the projected global increases in children surviving preterm births, research now needs to focus on understanding underlying mechanisms, and then to translate these insights into the development of preventive interventions. Review Registration PROSPERO CRD42013004965 Please see later in the article for the Editors' Summary PMID:24492409

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.

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

Does additional prenatal care in the home improve birth outcomes for women with a prior preterm delivery? A randomized clinical trial.

PubMed

Lutenbacher, Melanie; Gabbe, Patricia Temple; Karp, Sharon M; Dietrich, Mary S; Narrigan, Deborah; Carpenter, Lavenia; Walsh, William

2014-07-01

Women with a history of a prior preterm birth (PTB) have a high probability of a recurrent preterm birth. Some risk factors and health behaviors that contribute to PTB may be amenable to intervention. Home visitation is a promising method to deliver evidence based interventions. We evaluated a system of care designed to reduce preterm births and hospital length of stay in a sample of pregnant women with a history of a PTB. Single site randomized clinical trial. Eligibility: >18 years with prior live birth ≥20-<37 weeks gestation; <24 weeks gestation at enrollment; spoke and read English; received care at regional medical center. All participants (N = 211) received standard prenatal care. Intervention participants (N = 109) also received home visits by certified nurse-midwives guided by protocols for specific risk factors (e.g., depressive symptoms, abuse, smoking). Data was collected via multiple methods and sources including intervention fidelity assessments. Average age 27.8 years; mean gestational age at enrollment was 15 weeks. Racial breakdown mirrored local demographics. Most had a partner, high school education, and 62% had Medicaid. No statistically significant group differences were found in gestational age at birth. Intervention participants had a shorter intrapartum length of stay. Enhanced prenatal care by nurse-midwife home visits may limit some risk factors and shorten intrapartum length of stay for women with a prior PTB. This study contributes to knowledge about evidence-based home visit interventions directed at risk factors associated with PTB.

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.

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.

Trends in gestational age and birth weight in Chile, 1991–2008. A descriptive epidemiological study

PubMed Central

2012-01-01

Background Gestational age and birth weight are the principal determinants of newborn’s health status. Chile, a middle income country traditionally has public policies that promote maternal and child health. The availability of an exhaustive database of live births has allows us to monitor over time indicators of newborns health. Methods This descriptive epidemiological study included all live births in Chile, both singleton and multiple, from 1991 through 2008. Trends in gestational age affected the rate of prevalence (%) of preterm births (<37 weeks, including the categories < 32 and 32–36 weeks), term births (37–41) and postterm births (42 weeks or more). Trends in birth weight affected the prevalence of births < 1500 g, 1500–2499 g, 2500–3999 g, and 4000 g or more. Results Data from an exhaustive register of live births showed that the number of term and postterm births decreased and the number of multiple births increased significantly. Birth weights exceeding 4000 g did not vary. Total preterm births rose from 5.0% to 6.6%, with increases of 28% for the singletons and 31% for multiple births (p for trend < 0.0001). Some categories increased even more: specifically preterm birth < 32 weeks increased 32.3% for singletons and 50.6% for multiple births (p for trend 0.0001). The overall rate of low birth weight infants (<2500 g) increased from 4.6% to 5.3%. This variation was not statistically significant for singletons (p for trend = 0.06), but specific analyses exhibited an important increase in the category weighing <1500 g (42%) similar to that observed in multiple births (43%). Conclusions The gestational age and birth weight of live born child have significantly changed over the past two decades in Chile. Monitoring only overall rates of preterm births and low-birth-weight could provide restricted information of this important problem to public health. Monitoring them by specific categories provides a solid basis for planning interventions to reduce adverse perinatal outcomes. This epidemiological information also showed the need to assess several factors that could contribute to explain these trends, as the demographics changes, medical interventions and the increasing probability of survival of extremely and very preterm child. PMID:23116061

The APPLe Study: A Randomized, Community-Based, Placebo-Controlled Trial of Azithromycin for the Prevention of Preterm Birth, with Meta-Analysis

PubMed Central

van den Broek, Nynke R.; White, Sarah A.; Goodall, Mark; Ntonya, Chikondi; Kayira, Edith; Neilson, James P.

2009-01-01

Background Premature birth is the major cause of perinatal mortality and morbidity in both high- and low-income countries. The causes of preterm labour are multiple but infection is important. We have previously described an unusually high incidence of preterm birth (20%) in an ultrasound-dated, rural, pregnant population in Southern Malawi with high burdens of infective morbidity. We have now studied the impact of routine prophylaxis with azithromycin as directly observed, single-dose therapy at two gestational windows to try to decrease the incidence of preterm birth. Methods and Findings We randomized 2,297 pregnant women attending three rural and one peri-urban health centres in Southern Malawi to a placebo-controlled trial of oral azithromycin (1 g) given at 16–24 and 28–32 wk gestation. Gestational age was determined by ultrasound before 24 wk. Women and their infants were followed up until 6 wk post delivery. The primary outcome was incidence of preterm delivery, defined as <37 wk. Secondary outcomes were mean gestational age at delivery, perinatal mortality, birthweight, maternal malaria, and anaemia. Analysis was by intention to treat. There were no significant differences in outcome between the azithromycin group (n = 1,096) and the placebo group (n = 1,087) in respect of preterm birth (16.8% versus 17.4%), odds ratio (OR) 0.96, 95% confidence interval (0.76–1.21); mean gestational age at delivery (38.5 versus 38.4 weeks), mean difference 0.16 (−0.08 to 0.40); mean birthweight (3.03 versus 2.99 kg), mean difference 0.04 (−0.005 to 0.08); perinatal deaths (4.3% versus 5.0%), OR 0.85 (0.53–1.38); or maternal malarial parasitaemia (11.5% versus 10.1%), OR 1.11 (0.84–1.49) and anaemia (44.1% versus 41.3%) at 28–32 weeks, OR 1.07 (0.88–1.30). Meta-analysis of the primary outcome results with seven other studies of routine antibiotic prophylaxis in pregnancy (>6,200 pregnancies) shows no effect on preterm birth (relative risk 1.02, 95% confidence interval 0.86–1.22). Conclusions This study provides no support for the use of antibiotics as routine prophylaxis to prevent preterm birth in high risk populations; prevention of preterm birth requires alternative strategies. Trial registration Current Controlled Trials ISRCTN84023116 Please see later in the article for the Editors' Summary PMID:19956761

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.

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.

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.

Comparison of CRP and ALK-P serum levels in prediction of preterm delivery

PubMed Central

Shahshahan, Zahra; Iravani, Hoda

2016-01-01

Background: Preterm birth, defined as birth occurring before 37 weeks of gestation, is a common complication of pregnancy and may lead to death or long-term disability in newborns. Accurate diagnosis is, therefore, crucial for identifying those women undergoing preterm labor who are at greatest risk of preterm delivery. This may allow transport to a regional obstetrical center and permit time for corticosteroid therapy. Recent study recommends several markers such as CRP (C-reactive protein) and ALK-P (alkaline phosphatase) to predict preterm delivery. Materials and Methods: We select a total of 300 pregnant women that had symptoms of premature birth. All of them were under treatment with tocolytic and serum sample were taken to assess the level of CRP-ALKp. Cervix length and the time of response to tocolytic were measured. 110 pregnant of them had preterm labor. 110 patient that had a term labor selected as a control group. Results: Qualitative evaluation of efficacy CRP level on preterm delivery showed a significant relationship with 27 as a cut of point of CRP (P < 0.00001 –OR = 7.5). Investigate of effect of ALK-P level on preterm delivery refers to a significant relationship with 399 as a cut of point of ALKP (P < 0.00001 –OR = 5). Inquire of efficacy of CRP level and ALK-P level on preterm delivery demonstrate a significant relationship (P < 0.0001 1OR = 9). Conclusions: Maternal concentrations of CRP and ALKP and cervix length can be used as appropriate biomarker for predicting preterm labor and response to tocolytic therapy in pregnant women. PMID:26962519

[Comparative analysis of risk factors for preterm and small-for-gestational-age births].

PubMed

Zhong, Xin-Qi; Cui, Qi-Liang

2014-12-01

To compare the risk factors between preterm and small-for-gestational-age (SGA) births. A total of 1 270 newborns who had no obstetric risk factors or maternal diseases were enrolled in this study. Their mothers' stature, body weight, passive smoking, and history of abnormal pregnancy were investigated using the self-designed questionnaire. The infants were divided into four groups: preterm, appropriate-for-gestational-age (AGA), SGA, and term infants. Multivariate logistic regression analysis was performed to compare the risk factors between preterm and SGA births. A weight gain less than 9 kg during pregnancy increased the risks of preterm (OR=1.63, 95% CI: 1.12-2.07) and SGA (OR=1.92, 95% CI: 1.56-2.58). The histories of abortion (OR=1.46, 95% CI: 1.09-1.93) and preterm birth (OR=2.63, 95% CI: 1.81-3.92) were independent risk factors for preterm births, while low pre-pregnancy body mass index (<18.5) (OR=2.16, 95% CI: 1.53-3.16), short stature (<1.55 m) (OR=2.46, 95% CI: 1.78-3.48), and passive smoking (OR=2.24, 95% CI: 1.65-2.98) were independent risk factors for SGA births. Due to different risk factors between preterm and SGA births, specific preventive measures should be taken pertinently to reduce the incidence of the two bad pregnancy outcomes.

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.

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).

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.

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.

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.

Prediction of preterm deliveries from EHG signals using machine learning.

PubMed

Fergus, Paul; Cheung, Pauline; Hussain, Abir; Al-Jumeily, Dhiya; Dobbins, Chelsea; Iram, Shamaila

2013-01-01

There has been some improvement in the treatment of preterm infants, which has helped to increase their chance of survival. However, the rate of premature births is still globally increasing. As a result, this group of infants are most at risk of developing severe medical conditions that can affect the respiratory, gastrointestinal, immune, central nervous, auditory and visual systems. In extreme cases, this can also lead to long-term conditions, such as cerebral palsy, mental retardation, learning difficulties, including poor health and growth. In the US alone, the societal and economic cost of preterm births, in 2005, was estimated to be $26.2 billion, per annum. In the UK, this value was close to £2.95 billion, in 2009. Many believe that a better understanding of why preterm births occur, and a strategic focus on prevention, will help to improve the health of children and reduce healthcare costs. At present, most methods of preterm birth prediction are subjective. However, a strong body of evidence suggests the analysis of uterine electrical signals (Electrohysterography), could provide a viable way of diagnosing true labour and predict preterm deliveries. Most Electrohysterography studies focus on true labour detection during the final seven days, before labour. The challenge is to utilise Electrohysterography techniques to predict preterm delivery earlier in the pregnancy. This paper explores this idea further and presents a supervised machine learning approach that classifies term and preterm records, using an open source dataset containing 300 records (38 preterm and 262 term). The synthetic minority oversampling technique is used to oversample the minority preterm class, and cross validation techniques, are used to evaluate the dataset against other similar studies. Our approach shows an improvement on existing studies with 96% sensitivity, 90% specificity, and a 95% area under the curve value with 8% global error using the polynomial classifier.

A systematic review and meta-analysis to revise the Fenton growth chart for preterm infants

PubMed Central

2013-01-01

Background The aim of this study was to revise the 2003 Fenton Preterm Growth Chart, specifically to: a) harmonize the preterm growth chart with the new World Health Organization (WHO) Growth Standard, b) smooth the data between the preterm and WHO estimates, informed by the Preterm Multicentre Growth (PreM Growth) study while maintaining data integrity from 22 to 36 and at 50 weeks, and to c) re-scale the chart x-axis to actual age (rather than completed weeks) to support growth monitoring. Methods Systematic review, meta-analysis, and growth chart development. We systematically searched published and unpublished literature to find population-based preterm size at birth measurement (weight, length, and/or head circumference) references, from developed countries with: Corrected gestational ages through infant assessment and/or statistical correction; Data percentiles as low as 24 weeks gestational age or lower; Sample with greater than 500 infants less than 30 weeks. Growth curves for males and females were produced using cubic splines to 50 weeks post menstrual age. LMS parameters (skew, median, and standard deviation) were calculated. Results Six large population-based surveys of size at preterm birth representing 3,986,456 births (34,639 births < 30 weeks) from countries Germany, United States, Italy, Australia, Scotland, and Canada were combined in meta-analyses. Smooth growth chart curves were developed, while ensuring close agreement with the data between 24 and 36 weeks and at 50 weeks. Conclusions The revised sex-specific actual-age growth charts are based on the recommended growth goal for preterm infants, the fetus, followed by the term infant. These preterm growth charts, with the disjunction between these datasets smoothing informed by the international PreM Growth study, may support an improved transition of preterm infant growth monitoring to the WHO growth charts. PMID:23601190

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.

Survival, Morbidity, Growth and Developmental Delay for Babies Born Preterm in Low and Middle Income Countries – A Systematic Review of Outcomes Measured

PubMed Central

Gladstone, Melissa; Oliver, Clare; Van den Broek, Nynke

2015-01-01

Background Premature birth is the leading cause of neonatal death and second leading in children under 5. Information on outcomes of preterm babies surviving the early neonatal period is sparse although it is considered a major determinant of immediate and long-term morbidity. Methods Systematic review of studies reporting outcomes for preterm babies in low and middle income settings was conducted using electronic databases, citation tracking, expert recommendations and “grey literature”. Reviewers screened titles, abstracts and articles. Data was extracted using inclusion and exclusion criteria, study site and facilities, assessment methods and outcomes of mortality, morbidity, growth and development. The Child Health Epidemiology Reference Group criteria (CHERG) were used to assess quality. Findings Of 197 eligible publications, few (10.7%) were high quality (CHERG). The majority (83.3%) report on the outcome of a sample of preterm babies at time of birth or admission. Only 16.0% studies report population-based data using standardised mortality definitions. In 50.5% of studies, gestational age assessment method was unclear. Only 15.8% followed-up infants for 2 years or more. Growth was reported using standardised definitions but recommended morbidity definitions were rarely used. The criteria for assessment of neurodevelopmental outcomes was variable with few standardised tools - Bayley II was used in approximately 33% of studies, few studies undertook sensory assessments. Conclusions To determine the relative contribution of preterm birth to the burden of disease in children and to inform the planning of healthcare interventions to address this burden, a renewed understanding of the assessment and documentation of outcomes for babies born preterm is needed. More studies assessing outcomes for preterm babies who survive the immediate newborn period are needed. More consistent use of data is vital with clear and aligned definitions of health outcomes in newborn (preterm or term) and intervention packages aimed to save lives and improve health. PMID:25793703

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.

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.

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.

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

Development and Testing of the MyHealthyPregnancy App: A Behavioral Decision Research-Based Tool for Assessing and Communicating Pregnancy Risk

PubMed Central

Davis, Alexander L; Wong-Parodi, Gabrielle; Fischhoff, Baruch; Sadovsky, Yoel; Simhan, Hyagriv N

2017-01-01

Background Despite significant advances in medical interventions and health care delivery, preterm births in the United States are on the rise. Existing research has identified important, seemingly simple precautions that could significantly reduce preterm birth risk. However, it has proven difficult to communicate even these simple recommendations to women in need of them. Our objective was to draw on methods from behavioral decision research to develop a personalized smartphone app-based medical communication tool to assess and communicate pregnancy risks related to preterm birth. Objective A longitudinal, prospective pilot study was designed to develop an engaging, usable smartphone app that communicates personalized pregnancy risk and gathers risk data, with the goal of decreasing preterm birth rates in a typically hard-to-engage patient population. Methods We used semistructured interviews and user testing to develop a smartphone app based on an approach founded in behavioral decision research. For usability evaluation, 16 participants were recruited from the outpatient clinic at a major academic hospital specializing in high-risk pregnancies and provided a smartphone with the preloaded app and a digital weight scale. Through the app, participants were queried daily to assess behavioral risks, mood, and symptomology associated with preterm birth risk. Participants also completed monthly phone interviews to report technical problems and their views on the app’s usefulness. Results App use was higher among participants at higher risk, as reflected in reporting poorer daily moods (Odds ratio, OR 1.20, 95% CI 0.99-1.47, P=.08), being more likely to smoke (OR 4.00, 95% CI 0.93-16.9, P=.06), being earlier in their pregnancy (OR 1.07, 95% CI 1.02-1.12, P=.005), and having a lower body mass index (OR 1.07, 95% CI 1.00-1.15, P=.05). Participant-reported intention to breastfeed increased from baseline to the end of the trial, t15=−2.76, P=.01. Participants’ attendance at prenatal appointments was 84% compared with the clinic norm of 50%, indicating a conservatively estimated cost savings of ~US $450/patient over 3 months. Conclusions Our app is an engaging method for assessing and communicating risk during pregnancy in a typically hard-to-reach population, providing accessible and personalized distant obstetrical care, designed to target preterm birth risk, specifically. PMID:28396302

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.

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.

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.

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

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

Air pollution, inflammation and preterm birth in Mexico City: study design and methods.

PubMed

O'Neill, Marie S; Osornio-Vargas, Alvaro; Buxton, Miatta A; Sánchez, Brisa N; Rojas-Bracho, Leonora; Castillo-Castrejon, Marisol; Mordhukovich, Irina B; Brown, Daniel G; Vadillo-Ortega, Felipe

2013-03-15

Preterm birth is one of the leading causes of perinatal mortality and is associated with long-term adverse health consequences for surviving infants. Preterm birth rates are rising worldwide, and no effective means for prevention currently exists. Air pollution exposure may be a significant cause of prematurity, but many published studies lack the individual, clinical data needed to elucidate possible biological mechanisms mediating these epidemiological associations. This paper presents the design of a prospective study now underway to evaluate those mechanisms in a cohort of pregnant women residing in Mexico City. We address how air quality may act together with other factors to induce systemic inflammation and influence the duration of pregnancy. Data collection includes: biomarkers relevant to inflammation in cervico-vaginal exudate and peripheral blood, along with full clinical information, pro-inflammatory cytokine gene polymorphisms and air pollution data to evaluate spatial and temporal variability in air pollution exposure. Samples are collected on a monthly basis and participants are followed for the duration of pregnancy. The data will be used to evaluate whether ambient air pollution is associated with preterm birth, controlling for other risk factors. We will evaluate which time windows during pregnancy are most influential in the air pollution and preterm birth association. In addition, the epidemiological study will be complemented with a parallel toxicology invitro study, in which monocytic cells will be exposed to air particle samples to evaluate the expression of biomarkers of inflammation. Copyright © 2012 Elsevier B.V. All rights reserved.

Air pollution, inflammation and preterm birth in Mexico City: Study design and methods

PubMed Central

O’Neill, Marie S.; Osornio-Vargas, Alvaro; Buxton, Miatta A.; Sanchez, Brisa N.; Rojas-Bracho, Leonora; Castillo-Castrejon, Marisol; Mordhukovich, Irina B.; Brown, Daniel G.; Vadillo-Ortega, Felipe

2012-01-01

Preterm birth is one of the leading causes of perinatal mortality and is associated with long-term adverse health consequences for surviving infants. Preterm birth rates are rising worldwide, and no effective means for prevention currently exists. Air pollution exposure may be a significant cause of prematurity, but many published studies lack the individual, clinical data needed to elucidate possible biological mechanisms mediating these epidemiological associations. This paper presents the design of a prospective study now underway to evaluate those mechanisms in a cohort of pregnant women residing in Mexico City. We address how air quality may act together with other factors to induce systemic inflammation and influence the duration of pregnancy. Data collection includes: biomarkers relevant to inflammation in cervico-vaginal exudate and peripheral blood, along with full clinical information, pro-inflammatory cytokine gene polymorphisms and air pollution data to evaluate spatial and temporal variability in air pollution exposure. Samples are collected on a monthly basis and participants are followed for the duration of pregnancy. The data will be used to evaluate whether ambient air pollution is associated with preterm birth, controlling for other risk factors. We will evaluate which time windows during pregnancy are most influential in the air pollution and preterm birth association. In addition, the epidemiological study will be complemented with a parallel toxicology invitro study, in which monocytic cells will be exposed to air particle samples to evaluate the expression of biomarkers of inflammation. PMID:23177781

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.

Dynamics and complexity of body temperature in preterm infants nursed in incubators

PubMed Central

Jost, Kerstin; Pramana, Isabelle; Delgado-Eckert, Edgar; Kumar, Nitin; Datta, Alexandre N.; Frey, Urs; Schulzke, Sven M.

2017-01-01

Background Poor control of body temperature is associated with mortality and major morbidity in preterm infants. We aimed to quantify its dynamics and complexity to evaluate whether indices from fluctuation analyses of temperature time series obtained within the first five days of life are associated with gestational age (GA) and body size at birth, and presence and severity of typical comorbidities of preterm birth. Methods We recorded 3h-time series of body temperature using a skin electrode in incubator-nursed preterm infants. We calculated mean and coefficient of variation of body temperature, scaling exponent alpha (Talpha) derived from detrended fluctuation analysis, and sample entropy (TSampEn) of temperature fluctuations. Data were analysed by multilevel multivariable linear regression. Results Data of satisfactory technical quality were obtained from 285/357 measurements (80%) in 73/90 infants (81%) with a mean (range) GA of 30.1 (24.0–34.0) weeks. We found a positive association of Talpha with increasing levels of respiratory support after adjusting for GA and birth weight z-score (p<0.001; R2 = 0.38). Conclusion Dynamics and complexity of body temperature in incubator-nursed preterm infants show considerable associations with GA and respiratory morbidity. Talpha may be a useful marker of autonomic maturity and severity of disease in preterm infants. PMID:28448569

Cerebral white matter maturation patterns in preterm infants: an MRI T2 relaxation anisotropy and diffusion tensor imaging study

PubMed Central

Knight, Michael J.; Smith-Collins, Adam; Newell, Sarah; Denbow, Mark; Kauppinen, Risto A.

2017-01-01

Background and Purpose Preterm birth is associated with worse neurodevelopmental outcome, but brain maturation in preterm infants is poorly characterised with standard methods. We evaluated white matter (WM) of infant brains at term-equivalent age, as a function of gestational age at birth, using multi-modal MRI. Methods Infants born very pre-term (< 32 weeks gestation) and late pre-term (33-36 weeks gestation) were scanned at 3T at term-equivalent age using diffusion tensor imaging (DTI) and T2 relaxometry. MRI data were analysed using tract-based spatial statistics, and anisotropy of T2 relaxation was also determined. Principal component analysis and linear discriminant analysis were applied to seek the variables best distinguishing very pre-term and late pre-term groups. Results Across widespread regions of WM, T2 is longer in very pre-term infants than in late pre-term ones. These effects are more prevalent in regions of WM which myelinate earlier and faster. Similar effects are obtained from DTI, showing that fractional anisotropy (FA) is lower and radial diffusivity higher in the very pre-term group, with a bias towards earlier myelinating regions. Discriminant analysis shows high sensitivity and specificity of combined T2 relaxometry and DTI for the detection of a distinct WM development pathway in very preterm infants. T2 relaxation is anisotropic, depending on the angle between WM fibre and magnetic field, and this effect is modulated by FA. Conclusions Combined T2 relaxometry and DTI characterises specific patterns of retarded WM maturation, at term equivalent age, in infants born very pre-term relative to late pre-term. PMID:29205635

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.

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

A home calendar and recall method of last menstrual period for estimating gestational age in rural Bangladesh: a validation study.

PubMed

Gernand, Alison D; Paul, Rina Rani; Ullah, Barkat; Taher, Muhammad A; Witter, Frank R; Wu, Lee; Labrique, Alain B; West, Keith P; Christian, Parul

2016-10-21

The best method of gestational age assessment is by ultrasound in the first trimester; however, this method is impractical in large field trials in rural areas. Our objective was to assess the validity of gestational age estimated from prospectively collected date of last menstrual period (LMP) using crown-rump length (CRL) measured in early pregnancy by ultrasound. As part of a large, cluster-randomized, controlled trial in rural Bangladesh, we collected dates of LMP by recall and as marked on a calendar every 5 weeks in women likely to become pregnant. Among those with a urine-test confirmed pregnancy, a subset with gestational age of <15 weeks (n = 353) were enrolled for ultrasound follow-up to measure CRL. We compared interview-assessed LMP with CRL gestational age estimates and classification of preterm, term, and post-term births. LMP-based gestational age was higher than CRL by a mean (SD) of 2.8 (10.7) days; differences varied by maternal education and preterm birth (P < 0.05). Lin's concordance correlation coefficient was good at ultrasound [0.63 (95 % CI 0.56, 0.69)] and at birth [0.77 (95 % CI 0.73, 0.81)]. Validity of classifying preterm birth was high but post-term was lower, with specificity of 96 and 89 % and sensitivity of 86 and 67 %, respectively. Results were similar by parity. Prospectively collected LMP provided a valid estimate of gestational age and preterm birth in a rural, low-income setting and may be a suitable alternative to ultrasound in programmatic settings and large field trials. ClinicalTrials.gov NCT00860470.

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…

Morbidity in ≤1500-Gram Births in Spain, 1993-2011: Study of a Sample of 1200 Cases

PubMed Central

Gómez Esteban, Concepción; Sánchez Carrión, Juan J.; García Selgas, Fernando J.; Segovia Guisado, José M.

2017-01-01

Background and Objective. Preterm birth has a major impact on growth, and very preterm birth is associated with disabilities in numerous developmental domains. This article describes and quantifies morbidities in a sample of 1200 ≤1500-g births in Spain between 1993 and 2011 based on parent information, and it highlights several variables that influence these morbidities. Methods. Multiple method surveys using computer-assisted telephones interviewing and computer-assisted web interviewing methods. Sample design was intentional. Most subjects were contacted via their referral hospitals. Data collection was done from April 2013 to June 2014. Prior to the survey, extensive qualitative fieldwork was conducted, including nonparticipant observation in neonatal units and the design and analysis of discussion groups and interviews with professionals and families, including preterm adolescents. Results. A total of 44.2% of the sample were experiencing morbidity (mean: 1.788 morbidities per child). The most prevalent types were learning difficulties (34.4%) and attention deficit/hyperactivity disorder (31.5%). The most influential variables were male gender, age, lower birthweight, private hospital admission for birth, scarcity of health resources in the family’s residential area, non-Spanish maternal birthplace, and emotional distress in the primary carer. Conclusions. Overall, the total percentage of very low birth weight children with morbidities has decreased moderately between 1993 and 2011, thanks to major socio-sanitary improvements during this period. Biological and medical variables, rather than family factors, explain more accurately the presence of morbidities in children with birth weight ≤1500 g. PMID:28989948

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

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.

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

[Correlation between growth rate of corpus callosum and neuromotor development in preterm infants].

PubMed

Liu, Rui-Ke; Sun, Jie; Hu, Li-Yan; Liu, Fang

2015-08-01

To investigate the growth rate of corpus callosum by cranial ultrasound in very low birth weight preterm infants and to provide a reference for early evaluation and improvement of brain development. A total of 120 preterm infants under 33 weeks' gestation were recruited and divided into 26-29(+6) weeks group (n=64) and 30-32(+6) weeks group (n=56) according to the gestational age. The growth rate of corpus callosum was compared between the two groups. The correlation between the corpus callosum length and the cerebellar vermis length and the relationship of the growth rate of corpus callosum with clinical factors and the neuromotor development were analyzed. The growth rate of corpus callosum in preterm infants declined since 2 weeks after birth. Compared with the 30-32(+6) weeks group, the 26-29(+6) weeks group had a significantly lower growth rate of corpus callosum at 3-4 weeks after birth, at 5-6 weeks after birth, and from 7 weeks after birth to 40 weeks of corrected gestational age. There was a positive linear correlation between the corpus callosum length and the cerebellar vermis length. Small-for-gestational age infants had a low growth rate of corpus callosum at 2 weeks after birth. The 12 preterm infants with severe abnormal intellectual development had a lower growth rate of corpus callosum compared with the 108 preterm infants with non-severe abnormal intellectual development at 3-6 weeks after birth. The 5 preterm infants with severe abnormal motor development had a significantly lower growth rate of corpus callosum compared with the 115 preterm infants with non-severe abnormal motor development at 3-6 weeks after birth. The decline of growth rate of corpus callosum in preterm infants at 2-6 weeks after birth can increase the risk of severe abnormal neuromotor development.

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.

Births: Preliminary Data for 2011. National Vital Statistics Reports. Volume 61, Number 5

ERIC Educational Resources Information Center

Hamilton, Brady E.; Martin, Joyce A.; Ventura, Stephanie J.

2012-01-01

Objectives: This report presents preliminary data for 2011 on births in the United States. U.S. data on births are shown by age, live-birth order, race, and Hispanic origin of mother. Data on marital status, cesarean delivery, preterm births, and low birthweight are also presented. Methods: Data in this report are based on approximately 100…

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.

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.

Screen-and-treat program by point-of-care of Atopobium vaginae and Gardnerella vaginalis in preventing preterm birth (AuTop trial): study protocol for a randomized controlled trial.

PubMed

Bretelle, Florence; Fenollar, Florence; Baumstarck, Karine; Fortanier, Cécile; Cocallemen, Jean François; Serazin, Valérie; Raoult, Didier; Auquier, Pascal; Loubière, Sandrine

2015-10-19

International recommendations in favor of screening for vaginal infection in pregnancy are based on heterogeneous criteria. In most developed countries, the diagnosis of bacterial vaginosis is only recommended for women with high-risk of preterm birth. The Nugent score is currently used, but molecular quantification tools have recently been reported with a high sensitivity and specificity. Their value for reducing preterm birth rates and related complications remains unexplored. This trial was designed to assess the cost-effectiveness of a systematic screen-and-treat program based on a point-of-care technique for rapid molecular diagnosis, immediately followed by an appropriate antibiotic treatment, to detect the presence of abnormal vaginal flora (specifically, Atopobium vaginae and Gardnerella vaginalis) before 20 weeks of gestation in pregnant women in France. We hypothesized that this program would translate into significant reductions in both the rate of preterm births and the medical costs associated with preterm birth. A multicenter, open-label randomized controlled trial (RCT) will be conducted in which 20 French obstetrics and gynecology centers will recruit eligible pregnant women at less than 20 weeks gestation with singleton pregnancy and with a low-risk factor for preterm birth. Interventions will include a) an experimental group that will receive a systematic rapid screen-and-treat program from a point-of-care analysis using a molecular quantification method and b) a control group that will receive usual care management. Randomization will be in a 1:1 allocation ratio. The primary endpoint that will be assessed over a period of 12 months will be the incremental cost-effectiveness ratio (ICER) expressed as cost per avoided preterm birth before 37 weeks. Secondary endpoints will include ICER per avoided preterm birth before 24, 28 and 32 weeks, obstetrical outcomes, neonatal outcomes, rates of treatment failure and recurrence episodes for positive women. Uncertainty surrounding these estimates will be addressed using nonparametric bootstrapping and represented using cost-effectiveness acceptability curves. A total of 6,800 pregnant women will be included. This appropriate randomized controlled design will provide insight into the cost-effectiveness and therefore the potential cost savings of a rapid screen-and-treat strategy for molecular abnormal vaginal flora in pregnant women. National and international recommendations could be updated based on the findings of this study. ClinicalTrials.gov: NCT02288832 (registration date: 30 October 2014); Eudract: 2014-001559-22.

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.

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.

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.

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.

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

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.

Racial disparity in pathophysiologic pathways of preterm birth based on genetic variants

PubMed Central

Menon, Ramkumar; Pearce, Brad; Velez, Digna R; Merialdi, Mario; Williams, Scott M; Fortunato, Stephen J; Thorsen, Poul

2009-01-01

Objective To study pathophysiologic pathways in spontaneous preterm birth and possibly the racial disparity associating with maternal and fetal genetic variations, using bioinformatics tools. Methods A large scale candidate gene association study was performed on 1442 SNPs in 130 genes in a case (preterm birth < 36 weeks) control study (term birth > 37 weeks). Both maternal and fetal DNA from Caucasians (172 cases and 198 controls) and 279 African-Americans (82 cases and 197 controls) were used. A single locus association (genotypic) analysis followed by hierarchical clustering was performed, where clustering was based on p values for significant associations within each race. Using Ingenuity Pathway Analysis (IPA) software, known pathophysiologic pathways in both races were determined. Results From all SNPs entered into the analysis, the IPA mapped genes to specific disease functions. Gene variants in Caucasians were implicated in disease functions shared with other known disorders; specifically, dermatopathy, inflammation, and hematological disorders. This may reflect abnormal cervical ripening and decidual hemorrhage. In African-Americans inflammatory pathways were the most prevalent. In Caucasians, maternal gene variants showed the most prominent role in disease functions, whereas in African Americans it was fetal variants. The IPA software was used to generate molecular interaction maps that differed between races and also between maternal and fetal genetic variants. Conclusion Differences at the genetic level revealed distinct disease functions and operational pathways in African Americans and Caucasians in spontaneous preterm birth. Differences in maternal and fetal contributions in pregnancy outcome are also different between African Americans and Caucasians. These results present a set of explicit testable hypotheses regarding genetic associations with preterm birth in African Americans and Caucasians PMID:19527514

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.

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

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.

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.

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.

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.

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.

Mode of Birth Influences Preterm Infant Intestinal Colonization with Bacteroides Over the Early Neonatal Period

PubMed Central

Gregory, Katherine E.; LaPlante, Rose D.; Shan, Gururaj; Kumar, Deepak Vijaya; Gregas, Matt

2015-01-01

Background Intestinal colonization during infancy is important to short and long term health outcomes. Bacteroides, an early member of the intestinal microbiome, are necessary for breaking down complex molecules within the intestine and function to assist the body’s immune system in fighting against potentially harmful pathogens. Little is known about the colonization pattern of Bacteroides in preterm infants during the early neonatal period. Purpose This study measured Bacteroides colonization during the early neonatal period in a population of preterm infants based on clinical factors including mode of birth, antibiotics, and nutrition. Methods Bacterial DNA was isolated from 144 fecal samples from 29 preterm infants and analyzed using quantitative real time polymerase chain reaction (PCR). Analyses included liner mixed models to determine which clinical factors affect Bacteroides colonization of the infant gut. Results We found that infants born via vaginal canal had a higher rate of increase in Bacteroides than infants born via Cesarean section (p<.001). We did not find significant associations between antibiotic administration and differences in nutritional exposures with Bacteroides colonization. Implications for Practice These findings highlight the significant influence of mode of birth on Bacteroides colonization. While mode of birth is not always modifiable, these study findings may help develop interventions for preterm infants born via Cesarean section aimed at overcoming delayed Bacteroides colonization. Implications for Research Greater study of the intestinal microbiome and the clinical factors relevant to the preterm infant is needed so that interventions may be developed and tested, resulting in optimal microbial and immune health. PMID:26551793

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

Survival predictors of preterm neonates: Hospital based study in Iran (2010-2011)

PubMed Central

Haghighi, Ladan; Nojomi, Marzieh; Mohabbatian, Behnaz; Najmi, Zahra

2013-01-01

Background: Preterm birth (PTB) is responsible for 70% of neonatal mortalities. Various factors influence the risk of neonatal mortality in different populations. Objective: Our objective was to evaluate neonatal survival rate of preterm infants, and to define its predictors in Iranian population. Materials and Methods: This retrospective cohort study included all preterm (26-37 weeks) infants (n=1612) born alive in Shahid Akbar-abadi university hospital, during one year period (April 2010-2011). These infants were evaluated for fetal-neonatal, maternal, and pregnancy data. Survival analysis was performed and viability threshold and risk factors of neonatal mortality were evaluated. Results: Total overall mortality rate was 9.1%. Survival rate were 11.11% for extremely low birth weights (LBW) and 45.12% for very early PTBs. The smallest surviving infant was a 750 gr female with gestational age (GA) of 30 weeks and the youngest infants was a 970 gram female with GA of 25weeks plus 2 days. History of previous dead neonate, need to cardio-pulmonary resuscitation (CPR), need to neonatal intensive care unit (NICU) admission, postnatal administration of surfactant, presence of anomalies, Apgar score <7, multiple pregnancy, non-cephalic presentation, early PTB, very early PTB, LBW, very low birth weight (VLBW) and extremely low birth weight (ELBW), were risk factors for mortality in preterm neonates. Conclusion: Our study revealed that neonatal survival rate is dramatically influenced by birth weight especially under 1000grams, GA especially below 30 weeks, neonatal anomalies, history of previous dead fetus, multiple pregnancy, non- cephalic presentation, and need for NICU admission, resuscitation and respiratory support with surfactant PMID:24639721

Effect of Antibiotic Exposure on Nugent Score Among Pregnant Women With and Without Bacterial Vaginosis

PubMed Central

Anderson, Brenna; Zhao, Yuan; Andrews, William W.; Dudley, Donald J.; Sibai, Baha; Iams, Jay D.; Wapner, Ronald J.; Varner, Michael W.; Caritis, Steve N.; O’Sullivan, Mary Jo

2013-01-01

Objective To evaluate whether vaginal flora is altered by antibiotic exposure and associated with a risk of preterm birth, particularly among women with initially normal vaginal flora. Methods This was a secondary analysis of a randomized trial of metronidazole and erythromycin for the prevention of preterm birth among women with a positive fetal fibronectin test. Vaginal swabs for Nugent Gram stain score were collected for classification of bacterial vaginosis before and after antibiotic exposure and read at a central laboratory. Change in Nugent score was assessed for women with (score 7 or higher) or without (score lower than 7) bacterial vaginosis. Linear regression analysis evaluated whether change in Nugent score was associated with preterm birth. Results Two-hundred women without and 69 women with bacterial vaginosis had Gram stain performed before and after antibiotic therapy. Median Nugent score for all women declined from 4.0 to 2.0 after antibiotic therapy, p<0.001. Nugent score declined both for those without (from 2.0 to 1.5, p=0.11) and more dramatically, those with bacterial vaginosis (from 8.0 to 3.0, p<0.01). The components of the Nugent score that were affected by antibiotic exposure were similar among women with and without bacterial vaginosis. Antibiotic exposure and the change in Nugent score were unrelated to preterm birth among bacterial vaginosis-negative women. Conclusion Antibiotic exposure is not associated with preterm birth and does not worsen Nugent score among women with normal vaginal flora and positive fetal fibronectin. PMID:21422854

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

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.

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.

Estimated Effects of Disinfection By-products on Preterm Birth in a Population Served by a Single Water Utility

PubMed Central

Lewis, Chad; Suffet, Irwin H.; Hoggatt, Katherine; Ritz, Beate

2007-01-01

Objectives We evaluated the association between drinking-water disinfection by-products and preterm births using improved exposure assessment and more appropriate analysis methods than used in prior studies. Methods During 1999–2001, vital record data were obtained for a large, racially diverse population residing in 27 Massachusetts communities that received drinking water from a single public utility. This water system was monitored weekly for total trihalomethanes (TTHM), and it maintained geographically stable total TTHM levels system-wide during the study period. We employed proportional hazards regression to examine the effects of trimester-specific and shorter-term peak exposures to TTHM in drinking water late in pregnancy on preterm births in 37,498 singletons. Results For all women, our data suggested no more than a small increase, if any, in risk for delivering a preterm baby when exposed to ≥ 60 μg/L TTHM during the 4 weeks before birth [hazard ratio (HR) = 1.13; 95% confidence interval (CI), 0.95–1.35]. However, women who depended on a governmental source of payment for prenatal care were at increased risk when exposed at such levels late in gestation (HR = 1.39; 95% CI, 1.06–1.81). In contrast, exposure to high levels of TTHM during the second trimester and high exposure throughout pregnancy resulted in a 15–18% reduction in risk for preterm delivery in our population. Conclusions This finding confirms previous reports of a negative association during the second trimester. Our data also suggested a possible positive association with shorter-term third-trimester TTHM exposure in mothers of lower socioeconomic status. PMID:17384780

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

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

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.

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.

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

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…

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.

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

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.

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.

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.

Neurobehavior related to epigenetic differences in preterm infants

PubMed Central

Lester, Barry M; Marsit, Carmen J; Giarraputo, James; Hawes, Katheleen; LaGasse, Linda L; Padbury, James F

2015-01-01

Preterm birth is associated with medical problems affecting the neuroendocrine system, altering cortisol levels resulting in negative effects on newborn neurobehavior. Newborn neurobehavior is regulated by DNA methylation of NR3C1 and HSD11B2. Aim: Determine if methylation of HSD11B2 and NR3C1 is associated with neurobehavioral profiles in preterm infants. Patients & methods: Neurobehavior was measured before discharge from the hospital in 67 preterm infants. Cheek swabs were collected for DNA extraction. Results: Infants with the high-risk neurobehavioral profile showed more methylation than infants with the low-risk neurobehavioral profile at CpG3 for NR3C1 and less methylation of CpG3 for HSD11B2. Infants with these profiles were more likely to have increased methylation of NR3C1 and decreased methylation of HSD11B2 at these CpG sites. Conclusion: Preterm birth is associated with epigenetic differences in genes that regulate cortisol levels related to high-risk neurobehavioral profiles. PMID:26585459

Survival, morbidity, growth and developmental delay for babies born preterm in low and middle income countries - a systematic review of outcomes measured.

PubMed

Gladstone, Melissa; Oliver, Clare; Van den Broek, Nynke

2015-01-01

Premature birth is the leading cause of neonatal death and second leading in children under 5. Information on outcomes of preterm babies surviving the early neonatal period is sparse although it is considered a major determinant of immediate and long-term morbidity. Systematic review of studies reporting outcomes for preterm babies in low and middle income settings was conducted using electronic databases, citation tracking, expert recommendations and "grey literature". Reviewers screened titles, abstracts and articles. Data was extracted using inclusion and exclusion criteria, study site and facilities, assessment methods and outcomes of mortality, morbidity, growth and development. The Child Health Epidemiology Reference Group criteria (CHERG) were used to assess quality. Of 197 eligible publications, few (10.7%) were high quality (CHERG). The majority (83.3%) report on the outcome of a sample of preterm babies at time of birth or admission. Only 16.0% studies report population-based data using standardised mortality definitions. In 50.5% of studies, gestational age assessment method was unclear. Only 15.8% followed-up infants for 2 years or more. Growth was reported using standardised definitions but recommended morbidity definitions were rarely used. The criteria for assessment of neurodevelopmental outcomes was variable with few standardised tools - Bayley II was used in approximately 33% of studies, few studies undertook sensory assessments. To determine the relative contribution of preterm birth to the burden of disease in children and to inform the planning of healthcare interventions to address this burden, a renewed understanding of the assessment and documentation of outcomes for babies born preterm is needed. More studies assessing outcomes for preterm babies who survive the immediate newborn period are needed. More consistent use of data is vital with clear and aligned definitions of health outcomes in newborn (preterm or term) and intervention packages aimed to save lives and improve health.

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.

[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.

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.

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.

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…

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

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.

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.

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.

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.

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.

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

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.

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.

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

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.

Association of the gut microbiota mobilome with hospital location and birth weight in preterm infants.

PubMed

Ravi, Anuradha; Estensmo, Eva Lena F; Abée-Lund, Trine M L'; Foley, Steven L; Allgaier, Bernhard; Martin, Camilia R; Claud, Erika C; Rudi, Knut

2017-11-01

BackgroundThe preterm infant gut microbiota is vulnerable to different biotic and abiotic factors. Although the development of this microbiota has been extensively studied, the mobilome-i.e. the mobile genetic elements (MGEs) in the gut microbiota-has not been considered. Therefore, the aim of this study was to investigate the association of the mobilome with birth weight and hospital location in the preterm infant gut microbiota.MethodsThe data set consists of fecal samples from 62 preterm infants with and without necrotizing enterocolitis (NEC) from three different hospitals. We analyzed the gut microbiome by using 16S rRNA amplicon sequencing, shot-gun metagenome sequencing, and quantitative PCR. Predictive models and other data analyses were performed using MATLAB and QIIME.ResultSThe microbiota composition was significantly different between NEC-positive and NEC-negative infants and significantly different between hospitals. An operational taxanomic unit (OTU) showed strong positive and negative correlation with NEC and birth weight, respectively, whereas none showed significance for mode of delivery. Metagenome analyses revealed high levels of conjugative plasmids with MGEs and virulence genes. Results from quantitative PCR showed that the plasmid signature genes were significantly different between hospitals and in NEC-positive infants.ConclusionOur results point toward an association of the mobilome with hospital location in preterm infants.

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 ...

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.

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

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.

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.

Surface displacement based shape analysis of central brain structures in preterm-born children

NASA Astrophysics Data System (ADS)

Garg, Amanmeet; Grunau, Ruth E.; Popuri, Karteek; Miller, Steven; Bjornson, Bruce; Poskitt, Kenneth J.; Beg, Mirza Faisal

2016-03-01

Many studies using T1 magnetic resonance imaging (MRI) data have found associations between changes in global metrics (e.g. volume) of brain structures and preterm birth. In this work, we use the surface displacement feature extracted from the deformations of the surface models of the third ventricle, fourth ventricle and brainstem to capture the variation in shape in these structures at 8 years of age that may be due to differences in the trajectory of brain development as a result of very preterm birth (24-32 weeks gestation). Understanding the spatial patterns of shape alterations in these structures in children who were born very preterm as compared to those who were born at full term may lead to better insights into mechanisms of differing brain development between these two groups. The T1 MRI data for the brain was acquired from children born full term (FT, n=14, 8 males) and preterm (PT, n=51, 22 males) at age 8-years. Accurate segmentation labels for these structures were obtained via a multi-template fusion based segmentation method. A high dimensional non-rigid registration algorithm was utilized to register the target segmentation labels to a set of segmentation labels defined on an average-template. The surface displacement data for the brainstem and the third ventricle were found to be significantly different (p < 0.05) between the PT and FT groups. Further, spatially localized clusters with inward and outward deformation were found to be associated with lower gestational age. The results from this study present a shape analysis method for pediatric MRI data and reveal shape changes that may be due to preterm birth.

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...

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double-blind, placebo-controlled trial

PubMed Central

HASSAN, S. S.; ROMERO, R.; VIDYADHARI, D.; FUSEY, S.; BAXTER, J. K.; KHANDELWAL, M.; VIJAYARAGHAVAN, J.; TRIVEDI, Y.; SOMA-PILLAY, P.; SAMBAREY, P.; DAYAL, A.; POTAPOV, V.; O’BRIEN, J.; ASTAKHOV, V.; YUZKO, O.; KINZLER, W.; DATTEL, B.; SEHDEV, H.; MAZHEIKA, L.; MANCHULENKO, D.; GERVASI, M. T.; SULLIVAN, L.; CONDE-AGUDELO, A.; PHILLIPS, J. A.; CREASY, G. W.

2012-01-01

Objectives Women with a sonographic short cervix in the mid-trimester are at increased risk for preterm delivery. This study was undertaken to determine the ef cacy and safety of using micronized vaginal progesterone gel to reduce the risk of preterm birth and associated neonatal complications in women with a sonographic short cervix. Methods This was a multicenter, randomized, double-blind, placebo-controlled trial that enrolled asymptomatic women with a singleton pregnancy and a sonographic short cervix (10–20 mm) at 19 + 0to23 + 6 weeks of gestation. Women were allocated randomly to receive vaginal progesterone gel or placebo daily starting from 20 to 23 + 6 weeks until 36 + 6 weeks, rupture of membranes or delivery, whichever occurred rst. Randomization sequence was strati ed by center and history of a previous preterm birth. The primary endpoint was preterm birth before 33 weeks of gestation. Analysis was by intention to treat. Results Of 465 women randomized, seven were lost to follow-up and 458 (vaginal progesterone gel, n = 235; placebo, n = 223) were included in the analysis. Women allocated to receive vaginal progesterone had a lower rate of preterm birth before 33 weeks than did those allocated to placebo (8.9% (n = 21) vs 16.1% (n = 36); relative risk (RR), 0.55; 95% CI, 0.33–0.92; P = 0.02). The effect remained signi cant after adjustment for covariables (adjusted RR, 0.52; 95% CI, 0.31–0.91; P = 0.02). Vaginal progesterone was also associated with a signi cant reduction in the rate of preterm birth before 28 weeks(5.1%vs10.3%; RR, 0.50;95%CI, 0.25–0.97; P = 0.04) and 35 weeks (14.5% vs 23.3%; RR, 0.62; 95% CI, 0.42–0.92; P = 0.02), respiratory distress syndrome (3.0% vs 7.6%; RR, 0.39; 95% CI, 0.17–0.92; P = 0.03), any neonatal morbidity or mortality event (7.7% vs 13.5%; RR, 0.57; 95% CI, 0.33–0.99; P = 0.04) and birth weight < 1500 g (6.4% (15/234) vs 13.6% (30/220); RR, 0.47; 95% CI, 0.26–0.85; P = 0.01). There were no differences in the incidence of treatment-related adverse events between the groups. Conclusions The administration of vaginal progesterone gel to women with a sonographic short cervix in the mid-trimester is associated with a 45% reduction in the rate of preterm birth before 33 weeks of gestation and with improved neonatal outcome. PMID:21472815

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.

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.

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.

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

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.

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

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.

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.

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

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.

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.

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.

Preterm Prelabor Rupture of Membranes and Outcome of Very-Low-Birth-Weight Infants in the German Neonatal Network

PubMed Central

Hanke, Kathrin; Hartz, Annika; Manz, Maike; Bendiks, Meike; Heitmann, Friedhelm; Orlikowsky, Thorsten; Müller, Andreas; Olbertz, Dirk; Kühn, Thomas; Siegel, Jens; von der Wense, Axel; Wieg, Christian; Kribs, Angela; Stein, Anja; Pagel, Julia; Herting, Egbert; Göpel, Wolfgang; Härtel, Christoph

2015-01-01

Objective It was the aim of our study to evaluate the independent effect of preterm prelabor rupture of membranes (PPROM) as a cause of preterm delivery on mortality during primary hospital stay and significant morbidities in very-low-birth-weight (VLBW) infants < 32 weeks of gestation. Design Observational, epidemiological study design. Setting Population-based cohort, German Neonatal Network (GNN). Population 6102 VLBW infants were enrolled in GNN from 2009-2012, n=4120 fulfilled criteria for primary analysis (< 32 gestational weeks, no pre-eclampsia, HELLP (highly elevated liver enzymes and low platelets syndrome) or placental abruption as cause of preterm birth). Methods Multivariable logistic regression analyses included PPROM as potential risk factors for adverse outcomes and well established items such as gestational age in weeks, birth weight, antenatal steroids, center, inborn delivery, multiple birth, gender and being small-for-gestational-age. Results PPROM as cause of preterm delivery had no independent effect on the risk of early-onset sepsis, clinical sepsis and blood-culture proven sepsis, while gestational age proved to be the most important contributor to sepsis risk. The diagnosis of PPROM was associated with an increased risk for bronchopulmonary dysplasia (BPD; OR: 1.25, 95% CI: 1.02-1.55, p=0.03) but not with other major outcomes. Conclusions The diagnosis of PPROM per se is not associated with adverse outcome in VLBW infants < 32 weeks apart from a moderately increased risk for BPD. Randomized controlled trials with primary neonatal outcomes are needed to determine which subgroup of VLBW infants benefit from expectant or intentional management of PPROM. PMID:25856083

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

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

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

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.

Multivariate adaptive regression splines analysis to predict biomarkers of spontaneous preterm birth.

PubMed

Menon, Ramkumar; Bhat, Geeta; Saade, George R; Spratt, Heidi

2014-04-01

To develop classification models of demographic/clinical factors and biomarker data from spontaneous preterm birth in African Americans and Caucasians. Secondary analysis of biomarker data using multivariate adaptive regression splines (MARS), a supervised machine learning algorithm method. Analysis of data on 36 biomarkers from 191 women was reduced by MARS to develop predictive models for preterm birth in African Americans and Caucasians. Maternal plasma, cord plasma collected at admission for preterm or term labor and amniotic fluid at delivery. Data were partitioned into training and testing sets. Variable importance, a relative indicator (0-100%) and area under the receiver operating characteristic curve (AUC) characterized results. Multivariate adaptive regression splines generated models for combined and racially stratified biomarker data. Clinical and demographic data did not contribute to the model. Racial stratification of data produced distinct models in all three compartments. In African Americans maternal plasma samples IL-1RA, TNF-α, angiopoietin 2, TNFRI, IL-5, MIP1α, IL-1β and TGF-α modeled preterm birth (AUC train: 0.98, AUC test: 0.86). In Caucasians TNFR1, ICAM-1 and IL-1RA contributed to the model (AUC train: 0.84, AUC test: 0.68). African Americans cord plasma samples produced IL-12P70, IL-8 (AUC train: 0.82, AUC test: 0.66). Cord plasma in Caucasians modeled IGFII, PDGFBB, TGF-β1 , IL-12P70, and TIMP1 (AUC train: 0.99, AUC test: 0.82). Amniotic fluid in African Americans modeled FasL, TNFRII, RANTES, KGF, IGFI (AUC train: 0.95, AUC test: 0.89) and in Caucasians, TNF-α, MCP3, TGF-β3 , TNFR1 and angiopoietin 2 (AUC train: 0.94 AUC test: 0.79). Multivariate adaptive regression splines models multiple biomarkers associated with preterm birth and demonstrated racial disparity. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Correlation between tobacco control policies and preterm births and low birth weight in Europe.

PubMed

Díez-Izquierdo, Ana; Balaguer, Albert; Lidón-Moyano, Cristina; Martín-Sánchez, Juan Carlos; Galán, Iñaki; Fernández, Esteve; Martínez-Sánchez, Jose M

2018-01-01

To assess the correlation between tobacco control policies- particularly smoking bans in work and public places-and the prevalence of preterm births and low birth weight in the European countries. This is an ecological study and the unit of analysis set at the country level. Tobacco control data in Europe were obtained for the years 2010 and 2013 as measured by the Tobacco Control Scale (TCS), which reflects the level of implementation of tobacco control policies. Prevalence data for preterm births and low birth weight were obtained from two sources: the European Perinatal Health Report (EPHR), which provides data for 2010, and the Eurostat data, which includes the years 2013 and 2014. We analyzed the correlation between the TCS score and the prevalence of preterm birth and low birth weight in the European countries by means of Spearman (rsp) rank-correlation coefficients and their 95% confidence intervals (95%CI). The 2010 TCS was negatively correlated with the prevalence of preterm births before week 37 (rsp = -0.51; 95% CI: -0.77, -0.15; p = 0.006) and week 32 (rsp = -0.42; 95%CI: -0.73, -0.01; p = 0.030) and with the prevalence of the low birth weight (< 2500g, (rsp = -0.42; 95% CI: -0.66, -0.09; p = 0.028) in European countries in 2010. We found a statistically significant inverse correlation between the level of restrictions on smoking in public places and the prevalence of low birth weight (< 2500g rsp: -0.54; 95%CI: -0.72, -0.10; p = 0.017). The level of smoke-free legislation in European countries correlates with lower preterm birth prevalence rates at the ecological level. Given the important negative effects of premature births for the public health system, these data support greater implementation of smoke-free policies and tend to support the implementation of tobacco control policies, but more research is needed. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

Can stress biomarkers predict preterm birth in women with threatened preterm labor?

PubMed

García-Blanco, Ana; Diago, Vicente; Serrano De La Cruz, Verónica; Hervás, David; Cháfer-Pericás, Consuelo; Vento, Máximo

2017-09-01

Preterm birth is a major paediatric challenge difficult to prevent and with major adverse outcomes. Prenatal stress plays an important role on preterm birth; however, there are few stress-related models to predict preterm birth in women with Threatened Preterm Labor (TPL). The aim of this work is to study the influence of stress biomarkers on time until birth in TPL women. Eligible participants were pregnant women between 24 and 31 gestational weeks admitted to the hospital with TPL diagnosis (n=166). Stress-related biomarkers (α-amylase and cortisol) were determined in saliva samples after TPL diagnosis. Participants were followed-up until labor. A parametric survival model was constructed based on α-amylase, cortisol), TPL gestational week, age, parity, and multiple pregnancy. The model was adjusted using a logistic distribution and it was implemented as a nomogram to predict the labor probability at 7- and 14-day term. The time until labor was associated with cortisol (p=0.001), gestational week at TPL diagnosis (p=0.004), and age (p=0.02). Importantly, high cortisol levels at TPL diagnosis were predictive of latency to labor. Validation of the model yielded an optimum corrected AUC value of 0.63. High cortisol levels at TPL diagnosis may have an important role in the preterm birth prediction. Our statistical model implemented as a nomogram provided accurate predictions of individual prognosis of pregnant women. Copyright © 2017 Elsevier Ltd. All rights reserved.

Maternal resolution of grief after preterm birth: implications for infant attachment security.

PubMed

Shah, Prachi E; Clements, Melissa; Poehlmann, Julie

2011-02-01

This study explored the association between mothers' unresolved grief regarding their infant's preterm birth and infant-mother attachment security. We hypothesized that mothers with unresolved grief would be more likely to have insecurely attached infants at 16 months and that this association would be partially mediated by maternal interaction quality. This longitudinal study focused on 74 preterm infants (age of <36 weeks) and their mothers who were part of a larger study of high-risk infants. The present analysis included assessment of neonatal and socioeconomic risks at NICU discharge; maternal depression, Reaction to Preterm Birth Interview findings, and quality of parenting at a postterm age of 9 months; and infant-mother attachment at postterm age of 16 months. Associations among findings of grief resolution with the Reaction to Preterm Birth Interview, quality of parenting interactions, and attachment security were explored by using relative risk ratios and logistic and multivariate regression models. The relative risk of developing insecure attachment when mothers had unresolved grief was 1.59 (95% confidence interval: 1.03-2.44). Controlling for covariates (adjusted odds ratio: 2.94), maternal feelings of resolved grief regarding the preterm birth experience were associated with secure infant-mother attachment at 16 months. Maternal grief resolution and interaction quality were independent predictors of attachment security. Maternal grief resolution regarding the experience of preterm birth and the quality of maternal interactions have important implications for emerging attachment security for infants born prematurely.

Global report on preterm birth and stillbirth (3 of 7): evidence for effectiveness of interventions.

PubMed

Barros, Fernando C; Bhutta, Zulfiqar Ahmed; Batra, Maneesh; Hansen, Thomas N; Victora, Cesar G; Rubens, Craig E

2010-02-23

Interventions directed toward mothers before and during pregnancy and childbirth may help reduce preterm births and stillbirths. Survival of preterm newborns may also be improved with interventions given during these times or soon after birth. This comprehensive review assesses existing interventions for low- and middle-income countries (LMICs). Approximately 2,000 intervention studies were systematically evaluated through December 31, 2008. They addressed preterm birth or low birth weight; stillbirth or perinatal mortality; and management of preterm newborns. Out of 82 identified interventions, 49 were relevant to LMICs and had reasonable amounts of evidence, and therefore selected for in-depth reviews. Each was classified and assessed by the quality of available evidence and its potential to treat or prevent preterm birth and stillbirth. Impacts on other maternal, fetal, newborn or child health outcomes were also considered. Assessments were based on an adaptation of the Grades of Recommendation Assessment, Development and Evaluation criteria. Most interventions require additional research to improve the quality of evidence. Others had little evidence of benefit and should be discontinued. The following are supported by moderate- to high-quality evidence and strongly recommended for LMICs: Two interventions prevent preterm births--smoking cessation and progesterone. Eight interventions prevent stillbirths--balanced protein energy supplementation, screening and treatment of syphilis, intermittant presumptive treatment for malaria during pregnancy, insecticide-treated mosquito nets, birth preparedness, emergency obstetric care, cesarean section for breech presentation, and elective induction for post-term delivery. Eleven interventions improve survival of preterm newborns--prophylactic steroids in preterm labor, antibiotics for PROM, vitamin K supplementation at delivery, case management of neonatal sepsis and pneumonia, delayed cord clamping, room air (vs. 100% oxygen) for resuscitation, hospital-based kangaroo mother care, early breastfeeding, thermal care, and surfactant therapy and application of continued distending pressure to the lungs for respiratory distress syndrome The research paradigm for discovery science and intervention development must be balanced to address prevention as well as improve morbidity and mortality in all settings. This review also reveals significant gaps in current knowledge of interventions spanning the continuum of maternal and fetal outcomes, and the critical need to generate further high-quality evidence for promising interventions.

Mathematics Deficiencies in Children with Very Low Birth Weight or Very Preterm Birth

ERIC Educational Resources Information Center

Taylor, H. Gerry; Espy, Kimberly Andrews; Anderson, Peter J.

2009-01-01

Children with very low birth weight (VLBW, less than 1500 g) or very preterm birth (VPTB, less than 32 weeks gestational age or GA) have more mathematics disabilities or deficiencies (MD) and higher rates of mathematics learning disabilities (MLD) than normal birth weight term-born children (NBW, greater than 2500 g and greater than 36 weeks GA).…

Preterm Birth

MedlinePlus

... birth is when a baby is born too early, before 37 weeks of pregnancy have been completed. In 2016, preterm birth affected ... develop. Read Your Baby Grows Throughout Your Entire Pregnancy [PDF-312KB]. Babies born too early (especially before 32 weeks) have higher rates of ...

Maternal underweight and perinatal outcomes: a restrospective cohort study

PubMed

Vilar Sánchez, Ángel; Fernández Alba, Juan Jesús; González Macías, María Del Carmen; Paublete Herrera, María Del Carmen; Carnicer Fuentes, Concepción; Carral San Laureano, Florentino; Torrejón Cardoso, Rafael; Moreno Corral, Luis Javier

2017-06-05

Introduction: Some studies have linked maternal underweight with adverse perinatal outcomes such as spontaneous abortion, abruptio placentae, small for gestational age newborn, intrauterine growth retardation and preterm birth. Objective: To determine the influence of maternal underweight in the onset of labor, route of delivery, birth weight, Apgar score and preterm birth. Methods: Retrospective cohort study. We included pregnant women from the Hospital Universitario de Puerto Real. Period of study: 2002-2011. Study group: underweight at the beginning of gestation (BMI < 18.5 kg/m2). Control group: pregnant women with normal body mass index (BMI) at the beginning of gestation (18.5-24.9 kg/m2). The risk (OR) of induction of labor, cesarean section, small for gestational age newborn, macrosomia, 5’ Apgar score < 7, and preterm birth was calculated. Results: The prevalence of underweight was 2.5% versus 58.9% of pregnant women who had a normal BMI. We found no significant differences in the rate of induction of labor, fetal macrosomia, Apgar at 5’ < 7 or preterm delivery. Maternal underweight was associated with a decreased risk of caesarean section (adjusted OR 0.45, 95% CI 0.22 to 0.89) and an increased risk of small for gestational age newborn (adjusted OR 1.74; 95% CI 1.05 to 2.90). Conclusions: Maternal underweight at the start of pregnancy is associated with a lower risk of caesarean section and a greater risk of small for gestational age newborns (birth weight < P10).

State-specific trends in preterm delivery: are rates really declining among non-Hispanic African Americans across the United States?

PubMed

Vahratian, Anjel; Buekens, Pierre; Alexander, Greg R

2006-01-01

This study sought to examine state-specific trends in preterm delivery rates among non-Hispanic African Americans and to assess whether these rates are influenced by misclassification of gestational age. The sample population consisted of singleton non-Hispanic White and non-Hispanic African-American infants born in 1991 and 2001 to U.S. resident mothers. For both time periods, state-specific and national preterm delivery rates were calculated for all infants, stratified by infant race/ethnicity. Next, birth-weight distributions within strata of gestational age were studied to explore possible misclassifications of gestational age. Lastly, state-specific and national preterm delivery rates among infants who weighed less than 2,500 g were separately computed. National analyses showed that the frequency of preterm delivery increased by 15.8% among non-Hispanic Whites but declined by 10.3% among non-Hispanic African Americans over the same period. For both subgroups, a bimodal distribution of birth weights was apparent among preterm births at 28-31 weeks of gestation. The second peak with its cluster of normal-weight infants was more prominent among non-Hispanic African Americans in 1991 than in 2001. After excluding preterm infants who weighed 2,500 g or more, the national trends persisted. State-specific analyses showed that preterm delivery rates increased for both subgroups in 13 states during this period. Of these 13, 6 states had a number of non-Hispanic African-American births classified as preterm that were apparently term births mistakenly assigned short gestational ages. Such misclassification was more frequent in 1991 than in 2001 and inflated 1991 rates. There is heterogeneity in state-specific preterm delivery rates. Such differences are often overlooked when aggregate results are presented.

Development and validation of a simplified algorithm for neonatal gestational age assessment – protocol for the Alliance for Maternal Newborn Health Improvement (AMANHI) prospective cohort study

PubMed Central

Baqui, Abdullah; Ahmed, Parvez; Dasgupta, Sushil Kanta; Begum, Nazma; Rahman, Mahmoodur; Islam, Nasreen; Quaiyum, Mohammad; Kirkwood, Betty; Edmond, Karen; Shannon, Caitlin; Newton, Samuel; Hurt, Lisa; Jehan, Fyezah; Nisar, Imran; Hussain, Atiya; Nadeem, Naila; Ilyas, Muhammad; Zaidi, Anita; Sazawal, Sunil; Deb, Saikat; Dutta, Arup; Dhingra, Usha; Ali, Said Moh’d; Hamer, Davidson H.; Semrau, Katherine EA; Straszak–Suri, Marina; Grogan, Caroline; Bemba, Godfrey; Lee, Anne CC; Wylie, Blair J; Manu, Alexander; Yoshida, Sachiyo; Bahl, Rajiv

2017-01-01

Objective The objective of the Alliance for Maternal and Newborn Health Improvement (AMANHI) gestational age study is to develop and validate a programmatically feasible and simple approach to accurately assess gestational age of babies after they are born. The study will provide accurate, population–based rates of preterm birth in different settings and quantify the risks of neonatal mortality and morbidity by gestational age and birth weight in five South Asian and sub–Saharan African sites. Methods This study used on–going population–based cohort studies to recruit pregnant women early in pregnancy (<20 weeks) for a dating ultrasound scan. Implementation is harmonised across sites in Ghana, Tanzania, Zambia, Bangladesh and Pakistan with uniform protocols and standard operating procedures. Women whose pregnancies are confirmed to be between 8 to 19 completed weeks of gestation are enrolled into the study. These women are followed up to collect socio–demographic and morbidity data during the pregnancy. When they deliver, trained research assistants visit women within 72 hours to assess the baby for gestational maturity. They assess for neuromuscular and physical characteristics selected from the Ballard and Dubowitz maturation assessment scales. They also measure newborn anthropometry and assess feeding maturity of the babies. Computer machine learning techniques will be used to identify the most parsimonious group of signs that correctly predict gestational age compared to the early ultrasound date (the gold standard). This gestational age will be used to categorize babies into term, late preterm and early preterm groups. Further, the ultrasound–based gestational age will be used to calculate population–based rates of preterm birth. Importance of the study The AMANHI gestational age study will make substantial contribution to improve identification of preterm babies by frontline health workers in low– and middle– income countries using simple evaluations. The study will provide accurate preterm birth estimates. This new information will be crucial to planning and delivery of interventions for improving preterm birth outcomes, particularly in South Asia and sub–Saharan Africa. PMID:29163937

A Norwegian prospective study of preterm mother–infant interactions at 6 and 18 months and the impact of maternal mental health problems, pregnancy and birth complications

PubMed Central

Misund, Aud R; Bråten, Stein; Nerdrum, Per; Pripp, Are Hugo; Diseth, Trond H

2016-01-01

Objective Pregnancy, birth and health complications, maternal mental health problems following preterm birth and their possible impact on early mother–infant interaction at 6 and 18 months corrected age (CA) were explored. Predictors of mother–infant interaction at 18 months CA were identified. Design and methods This prospective longitudinal and observational study included 33 preterm mother–infant (<33 gestational age (GA)) interactions at 6 and 18 months CA from a socioeconomic low-risk, middle-class sample. The Parent–Child Early Relational Assessment (PCERA) scale was used to assess the mother–infant interaction. Results ‘Bleeding in pregnancy’ predicted lower quality in preterm mother–infant interaction in 6 PCERA scales, while high ‘maternal trait anxiety’ predicted higher interactional quality in 2 PCERA scales and ‘family size’ predicted lower interactional quality in 1 PCERA scale at 18 months CA. Mothers with symptoms of post-traumatic stress reactions, general psychological distress and anxiety at 2 weeks postpartum (PP) showed significantly better outcome than mothers without symptoms in 6 PCERA subscales at 6 months CA and 2 PCERA subscales at 18 months CA. Conclusions Our study detected a correspondence between early pregnancy complications and lower quality of preterm mother–infant interaction, and an association between high levels of maternal mental health problems and better quality in preterm mother–infant interaction. PMID:27147380

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.

Season and preterm birth in Norway: A cautionary tale.

PubMed

Weinberg, Clarice R; Shi, Min; DeRoo, Lisa A; Basso, Olga; Skjærven, Rolv

2015-06-01

Preterm birth is a common, costly and dangerous pregnancy complication. Seasonality of risk would suggest modifiable causes. 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. 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. 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. Published by Oxford University Press on behalf of the International Epidemiological Association 2015. This work is written by a US Government employee and is in the public domain in the US.

Long-Term Neurodevelopmental Outcomes After Preterm Birth

PubMed Central

Soleimani, Farin; Zaheri, Farzaneh; Abdi, Fatemeh

2014-01-01

Context: All over the the world, preterm birth is a major cause of death and important neurodevelopmental disorders. Approximately 9.6% (12.9 million) births worldwide are preterm. Evidence Acquisition: In this review, databases such as PubMed, EMBASE, ISI, Scopus, Google Scholar and Iranian databases including Iranmedex, and SID were researched to review relevant literature. A comprehensive search was performed using combinations of various keywords. Results: Cerebral palsy especially spastic diplegia, intellectual disability, visual (retinopathy of prematurity) and hearing impairments are the main neurodevelopmental disorders associated with prematurity. Conclusions: The increased survival of preterm infants was not associated with lower complications. There is now increasing evidence of sustained adverse outcomes into school age and adolescence, for preterm infants. PMID:25068052

Qualitative assessment of attitudes and knowledge on preterm birth in Malawi and within country framework of care

PubMed Central

2014-01-01

Background The overarching goal of this study was to qualitatively assess baseline knowledge and perceptions regarding preterm birth (PTB) and oral health in an at-risk, low resource setting surrounding Lilongwe, Malawi. The aims were to determine what is understood regarding normal length of gestation and how gestational age is estimated, to identify common language for preterm birth, and to assess what is understood as options for PTB management. As prior qualitative research had largely focused on patient or client-based focused groups, we primarily focused on groups comprised of community health workers (CHWs) and providers. Methods A qualitative study using focus-group discussions, incidence narrative, and informant interviews amongst voluntary participants. Six focus groups were comprised of CHWs, patient couples, midwives, and clinical officers (n = 33) at two rural health centers referring to Kamuzu Central Hospital. Semi-structured questions facilitated discussion of PTB and oral health (inclusive of periodontal disease), including definitions, perception, causation, management, and accepted interventions. Results Every participant knew of women who had experienced “a baby born too soon”, or preterm birth. All participants recognized both an etiology conceptualization and disease framework for preterm birth, distinguished PTB from miscarriage and macerated stillbirth, and articulated a willingness to engage in studies aimed at prevention or management. Identified gaps included: (1) discordance in the definition of PTB (i.e., 28–34 weeks or less than the 8th month, but with a corresponding fetal weight ranging 500 to 2300 grams); (2) utility and regional availability of antenatal steroids for prevention of preterm infant morbidity and mortality; (3) need for antenatal referral for at-risk women, or with symptoms of preterm birth. There was no evident preference for route of progesterone for the prevention of recurrent PTB. Conclusions Qualitative research was useful in (1) identifying gaps in knowledge in urban and rural Malawi, and (2) informing the development of educational materials and implementation of programs or trials ultimately aimed at reducing PTB. As a result of this qualitative work, implementation planning was focused on the gaps in knowledge, dissemination of knowledge (to both patients and providers), and practical solutions to barriers in known efficacious therapies. PMID:24690288

Measuring New Born Foot Length to Identify Small Babies in Need of Extra Care: a Cross-Sectional Hospital Based Study

PubMed Central

Mukherjee, Satarupa; Roy, Prithwish; Mitra, Souvik; Samanta, Moumita; Chatterjee, Sukanta

2013-01-01

Objective The neonatal mortality rate (NMR) continues to remain quite high, one important cause being preterm deliveries. The main obstacle in the pathway towards decreasing NMR is identification of babies in need of extra care. To analyze the utility of newborn foot length as a proxy measure for birth weight and gestational age. Methods A cross-sectional study done in a hospital of eastern India with 351 babies during 4 months. Right foot length of each recorded using a plastic, stiff ruler. Findings 48.1% babies were preterm, 51.8% low birth weight (LBW) and 33.3% very low birth weight (VLBW). Foot length less than 7.75 cm has 92.3% sensitivity and 86.3% specificity for identification of preterm neonates. For identification of LBW babies (<2500 gm) a foot length less than 7.85cm has 100% sensitivity and 95.3% specificity. Foot length less than 6.85 cm has 100% sensitivity and 94.9% specifity for identification of VLBW babies (<1500 gm). Conclusion Foot length may be used in the identification of LBW and preterm babies who are in need of extra care. PMID:24800008

Predictive accuracy of changes in transvaginal sonographic cervical length over time for preterm birth: a systematic review and metaanalysis.

PubMed

Conde-Agudelo, Agustin; Romero, Roberto

2015-12-01

To determine the accuracy of changes in transvaginal sonographic cervical length over time in predicting preterm birth in women with singleton and twin gestations. PubMed, Embase, Cinahl, Lilacs, and Medion (all from inception to June 30, 2015), bibliographies, Google scholar, and conference proceedings. Cohort or cross-sectional studies reporting on the predictive accuracy for preterm birth of changes in cervical length over time. Two reviewers independently selected studies, assessed the risk of bias, and extracted the data. Summary receiver-operating characteristic curves, pooled sensitivities and specificities, and summary likelihood ratios were generated. Fourteen studies met the inclusion criteria, of which 7 provided data on singleton gestations (3374 women) and 8 on twin gestations (1024 women). Among women with singleton gestations, the shortening of cervical length over time had a low predictive accuracy for preterm birth at <37 and <35 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 49% to 74%, 44% to 85%, 1.3 to 4.1, and 0.3 to 0.7, respectively. In women with twin gestations, the shortening of cervical length over time had a low to moderate predictive accuracy for preterm birth at <34, <32, <30, and <28 weeks of gestation with pooled sensitivities and specificities, and summary positive and negative likelihood ratios ranging from 47% to 73%, 84% to 89%, 3.8 to 5.3, and 0.3 to 0.6, respectively. There were no statistically significant differences between the predictive accuracies for preterm birth of cervical length shortening over time and the single initial and/or final cervical length measurement in 8 of 11 studies that provided data for making these comparisons. In the largest and highest-quality study, a single measurement of cervical length obtained at 24 or 28 weeks of gestation was significantly more predictive of preterm birth than any decrease in cervical length between these gestational ages. Change in transvaginal sonographic cervical length over time is not a clinically useful test to predict preterm birth in women with singleton or twin gestations. A single cervical length measurement obtained between 18 and 24 weeks of gestation appears to be a better test to predict preterm birth than changes in cervical length over time. Published by Elsevier Inc.

Low birthweight and preterm birth: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015.

PubMed

Silveira, Mariangela F; Victora, Cesar G; Horta, Bernardo L; da Silva, Bruna G C; Matijasevich, Alicia; Barros, Fernando C

2018-06-22

Despite positive changes in most maternal risk factors in Brazil, previous studies did not show reductions in preterm birth and low birthweight. We analysed trends and inequalities in these outcomes over a 33-year period in a Brazilian city. Four population-based birth cohort studies were carried out in the city of Pelotas in 1982, 1993, 2004 and 2015, with samples ranging from 4231 to 5914 liveborn children. Low birthweight (LBW) was defined as <2500 g, and preterm birth as less than 37 weeks of gestation. Information was collected on family income, maternal skin colour and other risk factors for low birthweight. Multivariable linear regression was used to estimate the contribution of risk factors to time trends in birthweight. Preterm births increased from 5.8% (1982) to 13.8% (2015), and LBW prevalence increased from 9.0% to 10.1%, being higher for boys and for children born to mothers with low income and brown or black skin colour. Mean birthweight remained stable, around 3200 g, but increased from 3058 to 3146 g in the poorest quintile and decreased from 3307 to 3227 g in the richest quintile. After adjustment for risk factors for LBW, mean birthweight was estimated to have declined by 160 g over 1982-2015 (reductions of 103 g in the poorest and 213 g in the richest quintiles). Data from four birth cohorts show that preterm births increased markedly. Mean birthweights remained stable over a 33-year period. Increased prevalence of preterm and early term births, associated with high levels of obstetric interventions, has offset the expected improvements due to reduction in risk factors for low birthweight.

Maternal exposure to heatwave and preterm birth in Brisbane, Australia.

PubMed

Wang, J; Williams, G; Guo, Y; Pan, X; Tong, S

2013-12-01

To quantify the short-term effects of maternal exposure to heatwave on preterm birth. An ecological study. A population-based study in Brisbane, Australia. All pregnant women who had a spontaneous singleton live birth in Brisbane between November and March in 2000-2010 were studied. Daily data on pregnancy outcomes, meteorological factors, and ambient air pollutants were obtained. The Cox proportional hazards regression model with time-dependent variables was used to examine the short-term impact of heatwave on preterm birth. A series of cut-off temperatures and durations were used to define heatwave. Multivariable analyses were also performed to adjust for socio-economic factors, demographic factors, meteorological factors, and ambient air pollutants. Spontaneous preterm births. The adjusted hazard ratios (HRs) ranged from 1.13 (95% CI 1.03-1.24) to 2.00 (95% CI 1.37-2.91) by using different heatwave definitions, after controlling for demographic, socio-economic, and meteorological factors, and air pollutants. Heatwave was significantly associated with preterm birth: the associations were robust to the definitions of heatwave. The threshold temperatures, instead of duration, could be more likely to influence the evaluation of birth-related heatwaves. The findings of this study may have significant public health implications as climate change progresses. © 2013 RCOG.

Predictors of preterm births and low birthweight in an inner-city hospital in sub-Saharan Africa.

PubMed

Olusanya, Bolajoko O; Ofovwe, Gabriel E

2010-11-01

Adverse birth outcomes remain significant contributors to perinatal mortality as well as developmental disabilities worldwide but limited evidence exists in sub-Saharan Africa based on a conceptual framework incorporating neighborhood context. This study therefore set out to determine the prevalence and risk factors for preterm births and low birthweight in an urban setting from this region. A cross-sectional study of all live births from May 2005 to December 2007 in an inner-city maternity hospital in Lagos, Nigeria. Factors predictive of preterm births and low birthweight were determined by unconditional multivariable logistic regression within a conceptual framework for adverse birth outcomes. Population attributable risk (PAR%) for each factor was also determined. Of the 4,314 newborns enrolled, 859 (19.9%) were preterm and 440 (10.2%) were low birthweight. One-third of mothers received no antenatal care while about 6% had HIV and another 6% had a history of hypertensive disorders. About 43% of the low birthweight infants were born full term. Maternal predictors of preterm delivery and/or low birthweight were marital status, occupation, residential accommodation with shared sanitation facilities, lack of antenatal care, absence of previous cesarean section, hypertensive disorders and antepartum hemorrhage. Gender and intrauterine growth restriction (IUGR) were also predictive of low birthweight. Premature rupture of membranes (PAR = 33.91%) and antepartum hemorrhage (PAR = 33.54%) were the leading contributors to preterm birth in contrast to IUGR (PAR = 82.28%) and premature rupture of membranes (PAR = 32.31%) for low birthweight. [corrected] The burden of preterm and low birthweight deliveries in this setting is associated with modifiable individual and neighborhood-level risk factors that warrant community-oriented public health interventions.

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.

Neuroendocrine mechanisms in pregnancy and parturition.

PubMed

Petraglia, Felice; Imperatore, Alberto; Challis, John R G

2010-12-01

The complex mechanisms controlling human parturition involves mother, fetus, and placenta, and stress is a key element activating a series of physiological adaptive responses. Preterm birth is a clinical syndrome that shares several characteristics with term birth. A major role for the neuroendocrine mechanisms has been proposed, and placenta/membranes are sources for neurohormones and peptides. Oxytocin (OT) is the neurohormone whose major target is uterine contractility and placenta represents a novel source that contributes to the mechanisms of parturition. The CRH/urocortin (Ucn) family is another important neuroendocrine pathway involved in term and preterm birth. The CRH/Ucn family consists of four ligands: CRH, Ucn, Ucn2, and Ucn3. These peptides have a pleyotropic function and are expressed by human placenta and fetal membranes. Uterine contractility, blood vessel tone, and immune function are influenced by CRH/Ucns during pregnancy and undergo major changes at parturition. Among the others, neurohormones, relaxin, parathyroid hormone-related protein, opioids, neurosteroids, and monoamines are expressed and secreted from placental tissues at parturition. Preterm birth is the consequence of a premature and sustained activation of endocrine and immune responses. A preterm birth evidence for a premature activation of OT secretion as well as increased maternal plasma CRH levels suggests a pathogenic role of these neurohormones. A decrease of maternal serum CRH-binding protein is a concurrent event. At midgestation, placental hypersecretion of CRH or Ucn has been proposed as a predictive marker of subsequent preterm delivery. While placenta represents the major source for CRH, fetus abundantly secretes Ucn and adrenal dehydroepiandrosterone in women with preterm birth. The relevant role of neuroendocrine mechanisms in preterm birth is sustained by basic and clinic implications.

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.

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

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.

First-trimester serum folate levels and subsequent risk of abortion and preterm birth among Japanese women with singleton pregnancies.

PubMed

Yamada, Takashi; Morikawa, Mamoru; Yamada, Takahiro; Kishi, Reiko; Sengoku, Kazuo; Endo, Toshiaki; Saito, Tsuyoshi; Cho, Kazutoshi; Minakami, Hisanori

2013-01-01

To determine whether a low serum folate level during the first trimester predicts subsequent late abortion, preterm birth, or fetal growth restriction (FGR). A prospective cohort study involving 5,075 women whose serum folate levels were measured during the first trimester. The participants were informed of their serum folate levels. The pregnancy duration, birthweight, rate of late abortion/preterm birth, and the rate of FGR did not differ significantly among the four groups classified according to folate status. The mean serum folate levels did not differ among quartiles classified according to the gestational week at the time of delivery. Nineteen of the 20 women with folate deficiency gave birth at term to infants with a birthweight of 3.132 ± 321 g; only one infant had FGR. Low serum folate levels during the first trimester were not associated with the risk of late abortion, preterm birth, or FGR.

[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.

Heightened risk of preterm birth and growth restriction after a first-born son.

PubMed

Bruckner, Tim A; Mayo, Jonathan A; Gould, Jeffrey B; Stevenson, David K; Lewis, David B; Shaw, Gary M; Carmichael, Suzan L

2015-10-01

In Scandinavia, delivery of a first-born son elevates the risk of preterm delivery and intrauterine growth restriction of the next-born infant. External validity of these results remains unclear. We test this hypothesis for preterm delivery and growth restriction using the linked California birth cohort file. We examined the hypothesis separately by race and/or ethnicity. We retrieved data on 2,852,976 births to 1,426,488 mothers with at least two live births. Our within-mother tests applied Cox proportional hazards (preterm delivery, defined as less than 37 weeks gestation) and linear regression models (birth weight for gestational age percentiles). For non-Hispanic whites, Hispanics, Asians, and American Indian and/or Alaska Natives, analyses indicate heightened risk of preterm delivery and growth restriction after a first-born male. The race-specific hazard ratios for preterm delivery range from 1.07 to 1.18. Regression coefficients for birth weight for gestational age percentile range from -0.73 to -1.49. The 95% confidence intervals for all these estimates do not contain the null. By contrast, we could not reject the null for non-Hispanic black mothers. Whereas California findings generally support those from Scandinavia, the null results among non-Hispanic black mothers suggest that we do not detect adverse outcomes after a first-born male in all racial and/or ethnic groups. Copyright © 2015 Elsevier Inc. All rights reserved.

Traffic-related air pollution and risk of preterm birth in the San Joaquin Valley of California.

PubMed

Padula, Amy M; Mortimer, Kathleen M; Tager, Ira B; Hammond, S Katharine; Lurmann, Frederick W; Yang, Wei; Stevenson, David K; Shaw, Gary M

2014-12-01

To evaluate associations between traffic-related air pollution during pregnancy and preterm birth in births in four counties in California during years 2000 to 2006. We used logistic regression to examine the association between the highest quartile of ambient air pollutants (carbon monoxide, nitrogen dioxide, particulate matter <10 and 2.5 μm) and traffic density during pregnancy and each of five levels of prematurity based on gestational age at birth (20-23, 24-27, 28-31, 32-33, and 34-36 weeks) versus term (37-42 weeks). We examined trimester averages and the last month and the last 6 weeks of pregnancy. Models were adjusted for birthweight, maternal age, race/ethnicity, education, prenatal care, and birth costs payment. Neighborhood socioeconomic status (SES) was evaluated as a potential effect modifier. There were increased odds ratios (ORs) for early preterm birth for those exposed to the highest quartile of each pollutant during the second trimester and the end of pregnancy (adjusted OR, 1.4-2.8). Associations were stronger among mothers living in low SES neighborhoods (adjusted OR, 2.1-4.3). We observed exposure-response associations for multiple pollutant exposures and early preterm birth. Inverse associations during the first trimester were observed. The results confirm associations between traffic-related air pollution and prematurity, particularly among very early preterm births and low SES neighborhoods.

Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants.

PubMed

Reiman, Milla; Parkkola, Riitta; Johansson, Reijo; Jääskeläinen, Satu K; Kujari, Harry; Lehtonen, Liisa; Haataja, Leena; Lapinleimu, Helena

2009-08-01

Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants.

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

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.

Spatiotemporal association between birth outcomes and coke production and steel making facilities in Alabama, USA: a cross-sectional study.

PubMed

Porter, Travis R; Kent, Shia T; Su, Wei; Beck, Heidi M; Gohlke, Julia M

2014-10-23

Previous research has shown exposure to air pollution increases the risk of adverse birth outcomes, although the effects of residential proximity to significant industrial point sources are less defined. The objective of the current study was to determine whether yearly reported releases from major industrial point sources are associated with adverse birth outcomes. Maternal residence from geocoded Alabama birth records between 1991 and 2010 were used to calculate distances from coke and steel production industries reporting emissions to the U.S. Environmental Protection Agency. Logistic regression models were built to determine associations between distance or yearly fugitive emissions (volatile organic compounds, polycyclic aromatic compounds, and metals) from reporting facilities and preterm birth or low birth weight, adjusting for covariates including maternal age, race, payment method, education level, year and parity. A small but significant association between preterm birth and residential proximity (≤5.0 km) to coke and steel production facilities remained after adjustment for covariates (OR 1.05 95% CI: 1.01,1.09). Above average emissions from these facilities of volatile organic compounds during the year of birth were associated with low birth weight (OR 1.17 95% CI: 1.06, 1.29), whereas metals emissions were associated with preterm birth (OR 1.07 95% CI: 1.01, 1.14). The present investigation suggests fugitive emissions from industrial point sources may increase the risk of adverse birth outcomes in surrounding neighborhoods. Further research teasing apart the relationship between exposure to emissions and area-level deprivation in neighborhoods surrounding industrial facilities and their combined effects on birth outcomes is needed.

Global Incidence of Preterm Birth.

PubMed

Tielsch, James M

2015-01-01

Estimating the incidence of preterm birth depends on accurate assessment of gestational age and pregnancy outcomes. In many countries, such data are not routinely collected, making global estimates difficult. A recent systematic approach to this problem has estimated a worldwide incidence of 11.1 per 100 live births in 2010. Significant variation in rates by country and region of the world was noted, but this variation is smaller than observed for a number of other important reproductive outcomes. Rates range from approximately 5% in some northern European countries to over 15% in some countries in sub-Saharan Africa and Asia. Time trends suggest that preterm birth incidence is increasing, but much of this change may reflect changes in medically induced early delivery practices as improvements in survival of preterm infants has improved. Whether there have been major changes in spontaneous preterm birth is unknown. New approaches to classifying etiologic heterogeneity have been proposed and offer the promise of developing specific interventions to address the range of underlying causes of this important health problem. © 2015 Nestec Ltd., Vevey/S. Karger AG, Basel.

Development of Hydro-Epidemiology Studies to Establish Relationships Between Source-Water Contamination and Preterm Birth

NASA Astrophysics Data System (ADS)

Padilla, I. Y.; Meeker, J.; Alshawabkeh, A.; Cordero, J.; Giese, R.; Loch-Caruso, R.

2010-12-01

Puerto Rico has the highest rate of preterm birth in United States. Preliminary investigations suggest that the increase in preterm birth rates in Puerto Rico cannot be explained by changes in known factors, and that there is sufficient evidence that exposure to some contaminants contributes to preterm birth. Contamination in Puerto Rico is extensive with more than 150 contaminated sites and a vast contamination of water resources. Of particular concern is the contamination in the north-coast karst aquifer. This aquifer provides important freshwater resources for human consumption. The same characteristics that make karst aquifers highly productive make them highly vulnerable to contamination and impart an enormous capacity to store and convey contaminants from sources to potential exposures zones. As a result, there is an inherent risk of exposure to contamination thorough groundwater. This presentation will address work being conducted to: assess the extent of groundwater contamination in the north coast of Puerto Rico; evaluate potential relationship between exposure to contaminants and preterm birth; develop new technology for discovery, transport characterization, and green remediation of contaminants in karst aquifers.

Maternal and neonatal interleukin-1 receptor antagonist genotype and pregnancy outcome in a population with a high rate of pre-term birth.

PubMed

Chaves, José Humberto Belmino; Babayan, Arthur; Bezerra, Cledna de Melo; Linhares, Iara M; Witkin, Steven S

2008-10-01

We evaluated associations between a length polymorphism in intron 2 of the gene coding for IL-1ra (gene symbol IL1RN) and pregnancy outcome in a population with a high rate of preterm birth. Subjects were pregnant women in Maceio, Brazil and their newborns. DNA was tested for IL1RN genotypes and alleles by gene amplification using primer pairs that spanned the polymorphic region. Every subject completed a detailed questionnaire. The frequency of allele 2 (IL1RN*2) carriage was elevated in mothers with a spontaneous preterm birth (SPTB) in the current pregnancy (P = 0.02) and also with a prior preterm delivery (P = .01). Both SPTB with intact membranes (P = 0.01) and SPTB preceded by pre-term premature rupture of membranes (P = .03) were associated with ILlRN*2 carriage. A previous fetal demise was more than twice as prevalent in mothers positive for two copies of IL1RN*2. Maternal carriage of ILlRN*2 increases susceptibility to inflammation-triggered spontaneous pre-term birth.

Under 5 mortality rate and its contributors in Zhejiang Province of China from 2000 to 2009

PubMed Central

Huang, Xin-Wen; Yang, Ru-Lai

2013-01-01

Objective By analyzing the under 5 mortality rate (U5MR) and its contributors in Zhejiang Province of China from 2000 to 2009, we tried to understand the trend of U5MR change in Zhejiang Province and thus propose strategies to reduce child mortality. Methods Thirty cities/counties/districts from Zhejiang Province were selected using stratified cluster sampling approach. Children under five years in these areas were enrolled as the subjects. The U5MR and its contributors were analyzed in terms of age, migration status of mothers, and other indicators using classic descriptive methods and Chi square test. Results The U5MR in Zhejiang Province showed a declining trend from 14.83‰ in 2000 to 9.49‰ in 2009. In 2009, the U5MR was significantly higher in the rural areas than in the urban areas (9.14‰ vs.6.50‰, P<0.01) and among floating populations than among local residents (12.12‰ vs. 6.42‰, P<0.01). Preterm birth/low birth weight was the leading cause of U5MR in 2009. More specifically, preterm birth/low birth weight, congenital heart disease, and birth asphyxia were the top three causes of deaths among infants (<1 year), while drowning, traffic accidents, and accidental falls were the leading causes of deaths among children (1-4 years). Conclusion The U5MR in Zhejiang Province in 2009 differed between urban areas and rural areas and between floating populations and local residents. The main causes of death differ between infants and young children. Prevention of preterm birth/low birth weight and congenital anomalies will reduce infant death, while the main intervention for young children is to avoid accidental injuries. PMID:26835282

Endogenous Human Milk Peptide Release Is Greater after Preterm Birth than Term Birth123

PubMed Central

Dallas, David C; Smink, Christina J; Robinson, Randall C; Tian, Tian; Guerrero, Andres; Parker, Evan A; Smilowitz, Jennifer T; Hettinga, Kasper A; Underwood, Mark A; Lebrilla, Carlito B; German, J Bruce; Barile, Daniela

2015-01-01

Background: Hundreds of naturally occurring milk peptides are present in term human milk. Preterm milk is produced before complete maturation of the mammary gland, which could change milk synthesis and secretion processes within the mammary gland, leading to differences in protein expression and enzymatic activity, thereby resulting in an altered peptide profile. Objective: This study examined differences in peptides present between milk from women delivering at term and women delivering prematurely. Methods: Nano-LC tandem mass spectrometry was employed to identify naturally occurring peptides and compare their abundances between term and preterm human milk samples at multiple time points over lactation. Term milk samples were collected from 8 mothers and preterm milk was collected from 14 mothers. The 28 preterm and 32 term human milk samples were divided into 4 groups based on day of collection (<14, 14–28, 29–41, and 42–58 d). Results: Preterm milk peptide counts, ion abundance, and concentration were significantly higher in preterm milk than term milk. Bioinformatic analysis of the cleavage sites for peptides identified suggested that plasmin was more active in preterm milk than term milk and that cytosol aminopeptidase and carboxypeptidase B2 likely contribute to extensive milk protein breakdown. Many identified milk peptides in both term and preterm milk overlapped with known functional peptides, including antihypertensive, antimicrobial, and immunomodulatory peptides. Conclusion: The high protein degradation by endogenous proteases in preterm milk might attenuate problems because of the preterm infant’s immature digestive system. This trial was registered at clinicaltrials.gov as NCT01817127. PMID:25540406

Traffic-Related Air Pollution and Risk of Preterm Birth in the San Joaquin Valley of California

PubMed Central

Padula, Amy M.; Mortimer, Kathleen M.; Tager, Ira B.; Hammond, S. Katharine; Lurmann, Frederick W.; Yang, Wei; Stevenson, David K.; Shaw, Gary M.

2014-01-01

We evaluated associations between traffic-related air pollution during pregnancy and preterm birth in births in four counties in California during years 2000–2006. We used logistic regression to examine the association between the highest quartile of ambient air pollutants (carbon monoxide, nitrogen dioxide, particulate matter <10 and 2.5 μm) and traffic density during pregnancy and each of five levels of prematurity based on gestational age at birth (20–23, 24–27, 28–31, 32–33 and 34–36 weeks) versus term (37–42 weeks). We examined trimester averages and the last month and last 6 weeks of pregnancy. Models were adjusted for birth weight, maternal age, race/ethnicity, education, prenatal care and birth costs payment. Neighborhood socioeconomic status was evaluated as a potential effect modifier. There were increased odds ratios for early preterm birth for those exposed to the highest quartile of each pollutant during the second trimester and the end of pregnancy (adjusted odds ratios: 1.4– 2.8). Associations were stronger among mothers living in low socioeconomic status neighborhoods (adjusted odds ratios: 2.1–4.3). We observed exposure-response associations for multiple pollutant exposures and early preterm birth. Inverse associations during the first trimester were observed. The results confirm associations between traffic-related air pollution and prematurity, particularly among very early preterm births and low socioeconomic status neighborhoods. PMID:25453347

Bacterial vaginosis and preterm birth.

PubMed

Manns-James, Laura

2011-01-01

Although it has been clear for more than 2 decades that bacterial vaginosis increases the risk for preterm birth in some women, it is not yet fully understood why this association exists or how best to modify the risk. Incomplete understanding of this polymicrobial condition and difficulties in classification contribute to the challenge. The relationship between altered vaginal microflora and preterm birth is likely mediated by host immune responses. Because treatment of bacterial vaginosis during pregnancy does not improve preterm birth rates, and may in fact increase them, screening and treatment of asymptomatic pregnant women is discouraged. Symptomatic women should be treated for symptom relief. This article reviews the pathophysiology of bacterial vaginosis and controversy surrounding management during pregnancy. Agents currently recommended for treatment of this condition are reviewed. © 2011 by the American College of Nurse-Midwives.

Nutritional recommendations for the late-preterm infant and the preterm infant after hospital discharge.

PubMed

Lapillonne, Alexandre; O'Connor, Deborah L; Wang, Danhua; Rigo, Jacques

2013-03-01

Early nutritional support of preterm infants is critical to life-long health and well being. Numerous studies have demonstrated that preterm infants are at increased risk of mortality and morbidity, including disturbances in brain development. To date, much attention has focused on enhancing the nutritional support of very low and extremely low birth weight infants to improve survival and quality of life. In most countries, preterm infants are sent home before their expected date of term birth for economic or other reasons. It is debatable whether these newborns require special nutritional regimens or discharge formulas. Furthermore, guidelines that specify how to feed very preterm infants after hospital discharge are scarce and conflicting. On the other hand, the late-preterm infant presents a challenge to health care providers immediately after birth when decisions must be made about how and where to care for these newborns. Considering these infants as well babies may place them at a disadvantage. Late-preterm infants have unique and often-unrecognized medical vulnerabilities and nutritional needs that predispose them to greater rates of morbidity and hospital readmissions. Poor or inadequate feeding during hospitalization may be one of the main reasons why late-preterm infants have difficulty gaining weight right after birth. Providing optimal nutritional support to late premature infants may improve survival and quality of life as it does for very preterm infants. In this work, we present a review of the literature and provide separate recommendations for the care and feeding of late-preterm infants and very preterm infants after discharge. We identify gaps in current knowledge as well as priorities for future research. Copyright © 2013 Mosby, Inc. All rights reserved.

The impact of low-dose aspirin on preterm birth: secondary analysis of a randomized controlled trial.

PubMed

Allshouse, A A; Jessel, R H; Heyborne, K D

2016-06-01

The objective of this study is to determine whether low-dose aspirin (LDA) reduced the rate of preterm birth (PTB) in a cohort of women at high risk for preeclampsia. Secondary analysis of the Maternal-Fetal Medicine Units High-Risk Aspirin trial. Preterm births were categorized by phenotype: indicated, spontaneous or due to preterm premature rupture of membranes (PPROMs). Of 1789 randomized women, 30.5% delivered before 37 weeks (18.5% indicated, 5.8% spontaneous and 6.2% following preterm PPROMs). Among women randomized to LDA, we observed a trend favoring fewer PTBs due to spontaneous preterm labor and preterm PPROMs, odds ratio (OR: 0.826 (0.620, 1.099)); the incidence of indicated PTBs appeared unchanged, OR: 0.999 (0.787, 1.268). Although not reaching significance, we observed an effect size similar to other studies of both low- and high-risk women. These results support findings from other studies assessing LDA as a PTB prevention strategy.

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.

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.

Segregation and preterm birth: The effects of neighborhood racial composition in North Carolina

EPA Science Inventory

Epidemiologic research suggests that racial segregation is associated with poor health among blacks in the United States (US). We used geocoded birth records and US census data to investigate whether neighborhood-level percent black is associated with preterm birth (PTB) for blac...

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.

Parental Leave Policy as a Strategy to Improve Outcomes among Premature Infants.

PubMed

Greenfield, Jennifer C; Klawetter, Susanne

2016-02-01

Although gains have been made in premature birth rates among racial and ethnic minority and low socioeconomic status populations, tremendous disparities still exist in both prematurity rates and health outcomes for preterm infants. Parental involvement is known to improve health outcomes for preterm babies. However, a gap in evidence exists around whether parental involvement can help ameliorate the disparities in both short- and long-term out-comes for their preterm children. Families more likely to experience preterm birth are also less likely to have access to paid leave and thus experience significant systemic barriers to involvement, especially when their newborns are hospitalized. This article describes the research gap in this area and explores pathways by which social workers may ameliorate disparities in preterm birth outcomes through practice, policy, and research.

Maternal experiences of racism and violence as predictors of preterm birth: rationale and study design.

PubMed

Rich-Edwards, J; Krieger, N; Majzoub, J; Zierler, S; Lieberman, E; Gillman, M

2001-07-01

Chronic psychological stress may raise the risk of preterm delivery by raising levels of placental corticotropin-releasing hormone (CRH). Women who have been the targets of racism or personal violence may be at particularly high risk of preterm delivery. The aims of this study are to examine the extent to which: (1) maternal experiences of racism or violence in childhood, adulthood, or pregnancy are associated with the risk of preterm birth; (2) CRH levels are prospectively associated with risk of preterm birth; and (3) CRH levels are associated with past and current maternal experiences of racism or violence. We have begun to examine these questions among women enrolled in Project Viva, a Boston-based longitudinal study of 6000 pregnant women and their children.

Preterm Birth and Its Long-Term Effects: Methylation to Mechanisms

PubMed Central

Parets, Sasha E.; Bedient, Carrie E.; Menon, Ramkumar; Smith, Alicia K.

2014-01-01

The epigenetic patterns established during development may influence gene expression over a lifetime and increase susceptibility to chronic disease. Being born preterm (<37 weeks of gestation) is associated with increased risk mortality and morbidity from birth until adulthood. This brief review explores the potential role of DNA methylation in preterm birth (PTB) and its possible long-term consequences and provides an overview of the physiological processes central to PTB and recent DNA methylation studies of PTB. PMID:25256426

Effects of Residential Indoor Air Quality and Household Ventilation on Preterm Birth and Term Low Birth Weight in Los Angeles County, California

PubMed Central

Wilhelm, Michelle; Ritz, Beate

2013-01-01

Objectives. The purpose of our study was to examine the effects of indoor residential air quality on preterm birth and term low birth weight (LBW). Methods. We evaluated 1761 nonsmoking women from a case-control survey of mothers who delivered a baby in 2003 in Los Angeles County, California. In multinomial logistic regression models adjusted for maternal age, education, race/ethnicity, parity and birthplace, we evaluated the effects of living with smokers or using personal or household products that may contain volatile organic compounds and examined the influence of household ventilation. Results. Compared with unexposed mothers, women exposed to secondhand smoke (SHS) at home had increased odds of term LBW (adjusted odds ratio [OR] = 1.36; 95% confidence interval [CI] =  0.85, 2.18) and preterm birth (adjusted OR = 1.27; 95% CI = 0.95, 1.70), although 95% CIs included the null. No increase in risk was observed for SHS-exposed mothers reporting moderate or high window ventilation. Associations were also observed for product usage, but only for women reporting low or no window ventilation. Conclusions. Residential window ventilation may mitigate the effects of indoor air pollution among pregnant women in Los Angeles County, California. PMID:23409879

Ethnicity and birth outcome: New Zealand trends 1980-2001. Part 1. Introduction, methods, results and overview.

PubMed

Craig, Elizabeth D; Mantell, Colin D; Ekeroma, Alec J; Stewart, Alistair W; Mitchell, Ed A

2004-12-01

New Zealand Government policy during the past decade has placed a high priority on closing socioeconomic and ethnic gaps in health outcome. To analyse New Zealand's trends in preterm and small for gestational age (SGA) births and late fetal deaths during 1980-2001 and to undertake ethnic specific analyses, resulting in risk factor profiles, for each ethnic group. De-identified birth registration data from 1 189 120 singleton live births and 5775 stillbirths were analysed for the period 1980-2001. Outcomes of interest included preterm birth, SGA and late fetal death while explanatory variables included maternal ethnicity, age and New Zealand Deprivation Index decile. Trend analysis was undertaken for 1980-1994 while multivariate logistic regression was used to explore risk factors for 1996-2001. During 1980-1994, preterm birth rates were highest amongst Maori women. Preterm rates increased by 30% for European/other women, in contrast to non-significant declines of 7% for Maori women and 4% for Pacific women during this period. During the same period, rates of SGA were highest amongst Maori women. Rates of SGA declined by 30% for Pacific women, 25% for Maori women and 19% for European/other women during this period. Rates of late fetal death were highest amongst Pacific women during 1980-1994, but declined by 49% during this period, the rate of decline being similar for all ethnic groups. The marked differences in both trend data and risk factor profiles for women in New Zealand's largest ethnic groups would suggest that unless ethnicity is specifically taken into account in future policy and planning initiatives, the disparities seen in this analysis might well persist into future generations.

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

Longitudinal Survey of Microbiota in Hospitalized Preterm Very Low Birth Weight Infants

PubMed Central

Patel, Aloka L.; Mutlu, Ece A.; Sun, Yan; Koenig, Lars; Green, Stefan; Jakubowicz, Andrew; Mryan, Janet; Engen, Phillip; Fogg, Louis; Chen, Andrea L.; Pombar, Xavier; Meier, Paula P.; Keshavarzian, Ali

2015-01-01

Objectives To examine the changes in bacteria in hospitalized preterm infants over the first month of life. Methods Rectal swabs were collected daily from 12 preterm infants. DNA was extracted from swabs from day of birth and weekly thereafter. Bacterial taxa were identified with next generation sequencing using universal bacterial primers targeted at the 16S rDNA on a 454 Roche titanium platform. Sequences were clustered into operational taxonomic units (OTUs), and taxonomy was assigned against the Greengenes databank using Qiime1.4. Quantitative PCR was used to determine the abundance of Bifidobacterium spp. Functional assessment of the microbiome was performed with PICRUSt. Results Average birth weight and gestational age were 1055g and 28 weeks, respectively. There were 6-35 different bacterial families identified in the day of birth samples, unrelated to mode of delivery. Richness decreased over hospitalization (week 1: 16.9±7.7 vs. weeks 3-5: 10.7±3.4, p<0.001). The Shannon diversity index demonstrated lowest diversity at birth, an increase at week 2, followed by a rapid decline at weeks 3-5, suggesting development of a more uniform microbiota composition after 2 weeks of NICU stay. Enterobacteriaceae, Staphylococcaceae, and Enterococcaceae constituted the majority of the bacterial families. Bifidobacterium spp. were infrequently detected at very low levels. PICRUSt analysis revealed enhancement of peroxisome, PPAR and adipocytokine signaling; plant-pathogen interaction; and aminobenzoate degradation pathways in week 1 samples. Conclusions Our results suggest that while preterm infants have individualized microbiota that are detectable at birth, the differences decrease during the neonatal intensive care unit hospitalization with increasing prominence of pathogenic microbiota. PMID:26230901

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.

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

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.

Immunizations for Preterm Babies

MedlinePlus

... preterm babies with a minimum birth weight of 2000 grams (about 4 lbs., 6 oz.) be treated ... immunization schedule. If birth weight is less than 2000 g, the AAP recommends administering the hepatitis B ...

Starting the conversation: community perspectives on preterm birth and kangaroo mother care in southern Malawi.

PubMed

Lydon, Megan; Longwe, Monica; Likomwa, Dyson; Lwesha, Victoria; Chimtembo, Lydia; Donohue, Pamela; Guenther, Tanya; Valsangar, Bina

2018-06-01

Despite introduction of Kangaroo Mother Care (KMC) in Malawi over a decade ago, preterm birth remains the leading cause of neonatal mortality. Although KMC is initiated in the health care facility, robust community follow-up is critical for survival and optimal development of preterm and low birth weight infants post-discharge. The objective of this qualitative study was to gain insight into community and health worker understanding, attitudes, beliefs and practices around preterm and low birth weight babies and KMC in Malawi. A total of 152 participants were interviewed in two districts in southern Malawi, Machinga and Thyolo, in April 2015. Focus group discussions (groups = 11, n = 132) were conducted with pregnant women, community members and women who have practiced KMC. In-depth interviews (n = 20) were conducted with fathers who have practiced KMC, community and religious leaders, and health workers. Purposive and snowball sampling were employed to identify participants. Thematic content analysis was conducted. KMC mothers and fathers only learned about KMC and care for preterm newborns after delivery of a child in need of this care. Men typically were not included in KMC counseling due to societal gender roles. Health facilities were the main source of information on KMC, however informal networks among women provided some degree of knowledge exchange. Community leaders were regarded as major facilitators of health information, conveners, key influencers, and policy-makers. Religious leaders were regarded as advocates and emotional support for families with preterm infants. Finally, while many participants initially had negative feelings towards preterm births and KMC, the large majority saw a shift in their perceptions through health counseling, peer modeling, and personal success with KMC. The findings offer several opportunities to improve KMC implementation including 1) earlier introduction of KMC to pregnant women and their families that are at-risk for preterm birth, 2) greater involvement of men in KMC counselling, practice and care for preterm infants, and 3) strengthening and defining partnerships with community and religious leaders. Finally, as parental perceptions of preterm infants and KMC improved with successful KMC practice, it is hopeful that KMC itself can positively affect social norms surrounding preterm infants, leading to a virtuous cycle of improved perceptions of preterm infants and increased uptake of KMC.

[Relationship between the thyroid autoimmunity and the risk of preterm birth in pregnant women: a meta-analysis].

PubMed

Li, M; Wang, S W; Huang, S; Mao, Y

2016-05-25

To evaluate the relationship between thyroid autoimmunity and the risk of preterm birth. Literature search was done among PubMed, Embase, Wanfang Medical Database, China Academic Journal Network Publishing Database and China Biology Medicine disc from Jan. 1(st) 1980 to July 31(st), 2015. (1) Literature were extracted according to inclusion and exclusion standards, and the quality of the extracted literature were evaluated by Newcastle-Ottawa Scale (NOS). (2) Meta-analysis was performed by RevMan 5 software formulated by using the Cochrane library databases. Various heterogeneity of the research was inspected firstly. According to the results of the inspection a certain effect model was selected (including fixed effects model, the random effects model) to be utilized in merger analysis. In this study pregnant women with both thyroid peroxidase antibodies (TPO-Ab) and thyroglobulin (TG-Ab) positive were defined as thyroid antibody positive pregnant women. Pregnant women with only TPO-Ab positive were defined as TPO-Ab positive pregnant women. Then the relationship of antibody positive and the risk of a preterm birth was analyzed respectively. (1) Ten cohort studies were enrolled, of which NOS scale score were 7 or higher. All the studies are of medium quality and above. A total of 1 322 cases of preterm birth occurred among 19 910 pregnant women. (2) Positive thyroid autoantibodies did not increase the risk of preterm birth in euthyroid pregnant women (OR=1.41, 95%CI: 0.83-2.40, P=0.200) or in pregnant women with hypothyroidism (OR=0.68, 95% CI: 0.32-1.44, P=0.310) . Positive TPO-Ab in euthyroid pregnant women increase the risk of preterm birth significantly (OR=2.08, 95%CI: 1.09-3.97, P=0.030), but positive TPO-Ab in pregnant women with hypothyroidism did not increase the risk of preterm birth significantly (OR=1.21, 95%CI: 0.65-2.24, P=0.550). Positive TPO-Ab is an independent risk factor of preterm birth in euthyroid pregnant women.

Global report on preterm birth and stillbirth (5 of 7): advocacy barriers and opportunities.

PubMed

Sather, Megan; Fajon, Anne-Véronique; Zaentz, Rachel; Rubens, Craig E

2010-02-23

Efforts to achieve the Millennium Development Goals (MDGs) to improve maternal and child health can be accelerated by addressing preterm birth and stillbirth. However, most global health stakeholders are unaware of the inextricable connections of these adverse pregnancy outcomes to maternal, newborn and child health (MNCH). Improved visibility of preterm births and stillbirths will help fuel investments and strengthen commitments in the discovery, development and delivery of low-cost solutions globally. This article addresses potential barriers and opportunities to increasing global awareness and understanding. Qualitative research was conducted to analyze current knowledge, attitudes and commitments toward preterm birth and stillbirth; identify advocacy challenges; and learn more about examples of programs that successfully advocate for research and appropriate interventions. Forty-one individuals from 14 countries on six continents were interviewed. They included maternal, newborn, and child health advocates and implementers, United Nations agency representatives, policymakers, researchers, and private and government donors. A common recognition of three advocacy challenges with regard to preterm birth and stillbirth emerged from these interviews: (1) lack of data about the magnitude and impact; (2) lack of awareness and understanding; and (3) lack of low-cost, effective and scalable interventions. Participants also identified advocacy opportunities. The first of these opportunities involves linking preterm birth and stillbirth to the MDGs, adding these outcomes to broader global health discussions and advocacy efforts, and presenting a united voice among advocates in the context of broader MNCH issues when addressing preterm birth and stillbirth. Another key opportunity is putting a human face to these tragedies--such as a parent who can speak to the personal impact on the family. Lastly, several interviewees suggested identifying and engaging champions to garner additional visibility and strengthen efforts. Ideal champions will work collaboratively with these and other maternal, newborn and child health issues. Advocacy efforts to add preterm births and stillbirths to broader MNCH goals, such as the MDGs, and to identify champions for these issues, will accelerate interdisciplinary efforts to reduce these adverse outcomes. The next article in this report presents an overview of related ethical considerations.

Mother's Emotional and Posttraumatic Reactions after a Preterm Birth: The Mother-Infant Interaction Is at Stake 12 Months after Birth.

PubMed

Petit, Anne-Cécile; Eutrope, Julien; Thierry, Aurore; Bednarek, Nathalie; Aupetit, Laurence; Saad, Stéphanie; Vulliez, Lauriane; Sibertin-Blanc, Daniel; Nezelof, Sylvie; Rolland, Anne-Catherine

2016-01-01

Very preterm infants are known to be at risk of developmental disabilities and behavioural disorders. This condition is supposed to alter mother-infant interactions. Here we hypothesize that the parental coping with the very preterm birth may greatly influence mother-infant interactions. 100 dyads were included in 3 university hospitals in France. Preterm babies at higher risk of neurodevelopmental sequelae (PRI>10) were excluded to target the maternal determinants of mother-infant interaction. We report the follow-up of this cohort during 1 year after very preterm birth, with regular assessment of infant somatic state, mother psychological state and the assessment of mother-infant interaction at 12 months by validated scales (mPPQ, HADS, EPDS, PRI, DDST and PIPE). We show that the intensity of post-traumatic reaction of the mother 6 months after birth is negatively correlated with the quality of mother-infant interaction at 12 months. Moreover, the anxious and depressive symptoms of the mother 6 and 12 months after birth are also correlated with the quality of mother-infant interaction at 12 months. By contrast, this interaction is not influenced by the initial affective state of the mother in the 2 weeks following birth. In this particular population of infants at low risk of sequelae, we also show that the quality of mother-infant interaction is not correlated with the assessment of the infant in the neonatal period but is correlated with the fine motor skills of the baby 12 months after birth. This study suggests that mothers' psychological condition has to be monitored during the first year of very preterm infants' follow-up. It also suggests that parental interventions have to be proposed when a post-traumatic, anxious or depressive reaction is suspected.

Recent pharmacological advances in the treatment of preterm membrane rupture, labour and delivery.

PubMed

Doggrell, Sheila A

2004-09-01

Preterm delivery (before 37 completed weeks of gestation) is the major determinant of infant mortality. In women with a previous preterm birth associated with bacterial vaginosis, prophylactic antibiotics (e.g., metronidazole) reduce the risk of preterm birth and low birth weight. Trichomonas vaginalis increases the risk of preterm delivery, but metronidazole is not beneficial for this and may even be detrimental. Antibiotic use (e.g., erythromycin) prolongs pregnancy in late premature rupture and has health benefits for the neonate. However, antibiotics are probably not useful in preterm labour. Intramuscular 17alpha-progesterone and vaginal progesterone reduce the rate of preterm labour in high-risk pregnancies, including previous spontaneous preterm delivery. Magnesium sulfate, beta2-adrenoceptor agonists and the oxytocin-receptor antagonist, atosiban, are effective in reducing uterine contractions short-term, but there is little evidence that this leads to improved outcomes for the neonate. However, tocolysis with calcium-channel blockers does seem to lead to better outcomes for the neonate. Fetal side effects, such as ductus arteriosus constriction and impaired renal function, are associated with the inhibition of prostaglandin synthesis with indomethacin. New approaches and more effective drugs are required in the treatment of preterm delivery.

Progesterone for the prevention of preterm birth: indications, when to initiate, efficacy and safety

PubMed Central

How, Helen Y; Sibai, Baha M

2009-01-01

Preterm birth is the leading cause of neonatal mortality and morbidity and long-term disability of non-anomalous infants. Previous studies have identified a prior early spontaneous preterm birth as the risk factor with the highest predictive value for recurrence. Two recent double blind randomized placebo controlled trials reported lower preterm birth rate with the use of either intramuscular 17 alpha-hydroxyprogesterone caproate (IM 17OHP-C) or intravaginal micronized progesterone suppositories in women at risk for preterm delivery. However, it is still unclear which high-risk women would truly benefit from this treatment in a general clinical setting and whether socio-cultural, racial and genetic differences play a role in patient’s response to supplemental progesterone. In addition the patient’s acceptance of such recommendation is also in question. More research is still required on identification of at risk group, the optimal gestational age at initiation, mode of administration, dose of progesterone and long-term safety. PMID:19436604

A role of stretch-activated potassium currents in the regulation of uterine smooth muscle contraction

PubMed Central

Buxton, Iain L O; Heyman, Nathanael; Wu, Yi-ying; Barnett, Scott; Ulrich, Craig

2011-01-01

Rates of premature birth are alarming and threaten societies and healthcare systems worldwide. Premature labor results in premature birth in over 50% of cases. Preterm birth accounts for three-quarters of infant morbidity and mortality. Children that survive birth before 34 weeks gestation often face life-long disability. Current treatments for preterm labor are wanting. No treatment has been found to be generally effective and none are systematically evaluated beyond 48 h. New approaches to the treatment of preterm labor are desperately needed. Recent studies from our laboratory suggest that the uterine muscle is a unique compartment with regulation of uterine relaxation unlike that of other smooth muscles. Here we discuss recent evidence that the mechanically activated 2-pore potassium channel, TREK-1, may contribute to contraction-relaxation signaling in uterine smooth muscle and that TREK-1 gene variants associated with human labor and preterm labor may lead to a better understanding of preterm labor and its possible prevention. PMID:21642947

Reducing tobacco smoking and smoke exposure to prevent preterm birth and its complications.

PubMed

Wagijo, Mary-Ann; Sheikh, Aziz; Duijts, Liesbeth; Been, Jasper V

2017-03-01

Tobacco smoking and smoke exposure during pregnancy are associated with a range of adverse health outcomes, including preterm birth. Also, children born preterm have a higher risk of complications including bronchopulmonary dysplasia and asthma when their mothers smoked during pregnancy. Smoking cessation in early pregnancy can help reduce the adverse impact on offspring health. Counselling interventions are effective in promoting smoking cessation and reducing the incidence of preterm birth. Peer support and incentive-based approaches are likely to be of additional benefit, whereas the effectiveness of pharmacological interventions, including nicotine replacement therapy, has not definitely been established. Smoke-free legislation can help reduce smoke exposure as well as maternal smoking rates at a population level, and is associated with a reduction in preterm birth. Helping future mothers to stop smoking and protect their children from second hand smoke exposure must be a key priority for health care workers and policy makers alike. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mothers and Fathers in NICU: The Impact of Preterm Birth on Parental Distress

PubMed Central

Ionio, Chiara; Colombo, Caterina; Brazzoduro, Valeria; Mascheroni, Eleonora; Confalonieri, Emanuela; Castoldi, Francesca; Lista, Gianluca

2016-01-01

Preterm birth is a stressful event for families. In particular, the unexpectedly early delivery may cause negative feelings in mothers and fathers. The aim of this study was to examine the relationship between preterm birth, parental stress and negative feelings, and the environmental setting of NICU. 21 mothers (age = 36.00 ± 6.85) and 19 fathers (age = 34.92 ± 4.58) of preterm infants (GA = 30.96 ± 2.97) and 20 mothers (age = 40.08 ± 4.76) and 20 fathers (age = 40.32 ± 6.77) of full-term infants (GA = 39.19 ± 1.42) were involved. All parents filled out the Parental Stressor Scale: Neonatal Intensive Care Unit, the Impact of Event Scale Revised, Profile of Mood States, the Multidimensional Scale of Perceived Social Support and the Post-Partum Bonding Questionnaire. Our data showed differences in emotional reactions between preterm and full-term parents. Results also revealed significant differences between mothers and fathers’ responses to preterm birth in terms of stress, negative feelings, and perceptions of social support. A correlation between negative conditions at birth (e.g., birth weight and Neonatal Intensive Care Unit stay) and higher scores in some scales of Impact of Event Scale Revised, Profile of Mood States and Post-Partum Bonding Questionnaire were found. Neonatal Intensive Care Unit may be a stressful place both for mothers and fathers. It might be useful to plan, as soon as possible, interventions to help parents through the experience of the premature birth of their child and to begin an immediately adaptive mode of care. PMID:27872669

Periodontal disease and oral health-related behavior as factors associated with preterm birth: a case-control study in south-eastern Brazil.

PubMed

Macedo, J F; Ribeiro, R A; Machado, F C; Assis, N M S P; Alves, R T; Oliveira, A S; Ribeiro, L C

2014-08-01

Several studies have suggested a link between periodontal disease and preterm birth, but the mechanism of how this occurs remains controversial. Therefore, this study aimed to investigate whether periodontal disease, defined according to two commonly used clinical definitions, is associated with preterm birth and to examine the association regarding oral health-related behaviors during pregnancy. This case-control study included women 18-40 years of age. Demographic and socio-economic data, information on current and previous pregnancies, and data on dental health-related behaviors and periodontal clinical parameters were collected within 48 h postpartum. Periodontal disease was assessed according to two definitions: four or more teeth with at least one site showing a probing depth of ≥ 4 mm and clinical attachment level of ≥ 3 mm (Definition 1); or at least one site with probing depth and clinical attachment level of ≥ 4 mm (Definition 2). The chi-square test was used to examine differences in the proportion of categorical variables. Bivariate analysis was performed to analyze the proportion of preterm births with respect to independent variables. Multiple logistic regression analyses were used to assess the association between periodontal disease and preterm birth. Odds ratios (ORs) were calculated with a 95% confidence interval (95% CI). A total of 296 postpartum women met the inclusion criteria. The case group included 74 women who delivered a preterm neonate (< 37 wk of gestation) and the control group included 222 women with deliveries at term (≥ 37 wk). Periodontal disease according to Definition 1 was not associated with fewer weeks of gestation (adjusted OR (OR adjusted ) = 1.62; 95% CI = 0.80-3.29; p = 0.178). However, a significant association was found between periodontal disease, according to Definition 2, and preterm birth (OR adjusted = 1.98; 95% CI = 1.14-3.43; p = 0.015). Increased appetite and a low number of daily toothbrushings were associated with preterm birth, regardless of the definition of periodontal disease used. Periodontal disease defined according to Definition 2 and unfavorable oral health-related behavior were factors associated with preterm birth. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Estimated Number of Preterm Births and Low Birth Weight Children Born in the United States Due to Maternal Binge Drinking

PubMed Central

Truong, Khoa D; Reifsnider, Odette S; Mayorga, Maria E; Spitler, Hugh

2013-01-01

Objective To estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. Methods 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. Results 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%). Conclusion Maternal binge drinking contributed significantly to PTB and LBW differentially across sociodemographic groups. PMID:22711260

Benefits of smoking bans on preterm and early-term births: a natural experimental design in Switzerland.

PubMed

Vicedo-Cabrera, Ana M; Schindler, Christian; Radovanovic, Dragana; Grize, Leticia; Witassek, Fabienne; Dratva, Julia; Röösli, Martin; Perez, Laura

2016-12-01

Birth outcomes are relevant for future children's heath. Capitalising on a natural experimental design in Switzerland, we evaluated how regional smoking bans introduced at different time points affected birth outcomes, including preterm and early-term births. We used birth registry data of all singleton neonates born in Switzerland (2007-2012). We developed canton-specific interrupted time-series followed by random meta-analysis to evaluate the benefits of smoking bans on preterm (<37 gestational weeks) and early-term (37-38 gestational weeks) births. Heterogeneity across type of ban and contextual characteristics was explored through metaregression. A time-to-event approach was used for evaluating duration of pregnancy under the smoking bans and effects, taking into account individual maternal factors. We observed a decrease in the risk of preterm birth of 3.6% (95% CI, -9.3% to 2.5%), and early-term birth of 5.0% (95% CI -7.5% to -2.5%). Results showed a clear dose-response relationship. Greater risk reductions were obtained for preterm births in areas with more comprehensive bans (-6.8%; 95% CI -12.1% to 0.1%), and for pregnancies with the longest gestational time under smoking bans (HR, 0.991; 95% CI 0.984 to 0.997 per 10% increase in duration). Benefits were unequal across outcomes and characteristics of cantons and mothers. Smoking bans resulted in improved birth outcomes in Switzerland with cantons that adopted more comprehensive smoking bans achieving greater benefits. Early-term births constitute a previously ignored though important group. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The Vaginal Eukaryotic DNA Virome and Preterm Birth.

PubMed

Wylie, Kristine M; Wylie, Todd N; Cahill, Alison G; Macones, George A; Tuuli, Methodius G; Stout, Molly J

2018-05-05

Despite decades of attempts to link infectious agents to preterm birth, an exact causative microbe or community of microbes remains elusive. Culture-independent sequencing of vaginal bacterial communities demonstrates community characteristics are associated with preterm birth, although none are specific enough to apply clinically. Viruses are important components of the vaginal microbiome and have dynamic relationships with vaginal bacterial communities. We hypothesized that vaginal eukaryotic DNA viral communities (the "vaginal virome") either alone or in the context of bacterial communities are associated with preterm birth. The objective of this study was to use high-throughput sequencing to examine the vaginal eukaryotic DNA virome in a cohort of pregnant women and examine associations between vaginal community characteristics and 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 at routine prenatal visits. DNA was extracted, bacterial communities were characterized by 16S rRNA gene sequencing, and eukaryotic viral communities were characterized by enrichment of viral nucleic acid with the ViroCap targeted sequence capture panel followed by nucleic acid sequencing. Viral communities were analyzed according to presence/absence of viruses, diversity, dynamics over time, and association with bacterial community data obtained from the same specimens. Sixty subjects contributed 128 vaginal swabs longitudinally across pregnancy. Twenty-four patients delivered preterm. Participants were predominantly African-American (65%). Six families of eukaryotic DNA viruses were detected in the vaginal samples. At least 1 virus was detected in 80% of women. No specific virus or group of viruses was associated with preterm delivery. Higher viral richness was significantly associated with preterm delivery in the full group and in the African American subgroup (P=0.0005 and P=0.0003, respectively). Having both high bacterial diversity and high viral diversity in the first trimester was associated with the highest risk for preterm birth. Higher vaginal viral diversity is associated with preterm birth. Changes in vaginal virome diversity appear similar to changes in the vaginal bacterial microbiome over pregnancy, suggesting that underlying physiology of pregnancy may regulate both bacterial and viral communities. Copyright © 2018 Elsevier Inc. All rights reserved.

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

Short term effect of air pollution, noise and heat waves on preterm births in Madrid (Spain).

PubMed

Arroyo, Virginia; Díaz, Julio; Ortiz, Cristina; Carmona, Rocío; Sáez, Marc; Linares, Cristina

2016-02-01

Preterm birth (PTB) refers to delivery before 37 weeks of gestation and represents the leading cause of early-life mortality and morbidity in developed countries. PTB can lead to serious infant health outcomes. The etiology of PTB remains uncertain, but epidemiologic studies have consistently shown elevated risks with different environmental variables as traffic-related air pollution (TRAP). The aim of the study was to evaluate with time series methodology the short-term effect of air pollutants, noise levels and ambient temperature on the number of births and preterm births occurred in Madrid City during the 2001-2009 period. A time-series analysis was performed to assess the short term impact of daily mean concentrations (µg/m(3)) of PM2.5 and PM10, O3 and NO2. Measurements of Acoustic Pollution in dB(A) analyzed were: Leqd, equivalent diurnal noise level and Leqn, equivalent nocturnal noise level. Maximum and Minimum daily temperature (°C), mean Humidity in the air (%) and Atmospheric Pressure (HPa), were included too. Linear trends, seasonality, as well as the autoregressive nature of the series itself were controlled. We added as covariate the day of the week too. Autoregressive over-dispersed Poisson regression models were performed and the environmental variables were included with short-term lags (from 0 to 7 days) in reference to the date of birth. Firstly, simple models for the total number of births and preterm births were done separately. In a second stage, a model for total births adjusted for preterm births was performed. A total of 298,705 births were analyzed. The results of the final models were expressed in relative risks (RRs) for interquartile increase. We observed evidence of a short term effect at Lag 0, for the following environmental variables analyzed, PM2.5 (RR: 1.020; 95% CI:(1.008 1.032)) and O3 (RR: 1.012; 95% CI:(1.002 1.022)) concentrations and Leqd (RR: 1.139; 95% CI:( (1.124 1.154)) for the total number of births, and besides these, heat temperatures at Lag 1 (RR: 1.055; 95% CI:( (1.018 1.092)) on preterm births in Madrid City during the studied period. In the model adjusted for preterm births, similar RR was obtained for the same environmental variables. Especially PM2.5, diurnal noise levels and O3 have a short-term impact on total births and heat temperatures on preterm births in Madrid City during the studied period. Our results suggest that, given the widespread exposure of the population to the environmental factors analyzed and the possible effects on long-term health associated to low birth weight. There is a clear need to minimize this exposure through the decrease of air pollution and noise levels and through the behavior modification of the mothers. Copyright © 2015 Elsevier Inc. All rights reserved.

How I transfuse red blood cells and platelets to infants with the anemia and thrombocytopenia of prematurity

PubMed Central

Strauss, Ronald G.

2010-01-01

Many aspects of hematopoiesis are either incompletely developed in preterm infants or still functioning to serve the fetus (i.e., the intrauterine counterpart to a liveborn preterm neonate). This delayed development and/or slow adaptation to extrauterine life diminishes the capacity of the neonate to produce red blood cells (RBCs), platelets (PLTs), and neutrophils—particularly during the stress of life-threatening illnesses encountered after preterm birth such as sepsis, severe pulmonary dysfunction, necrotizing enterocolitis, and immune cytopenias. The serious medical and/or surgical problems of preterm birth can be further complicated by phlebotomy blood losses, bleeding, hemolysis, and consumptive coagulopathy. To illustrate, some preterm infants, especially those with birth weight less than 1.0 kg and respiratory distress, are given numerous RBC transfusions early in life owing to several interacting factors. Neonates delivered before 28 weeks of gestation (birth weight, <1.0 kg) are born before the bulk of iron transport has occurred from mother to fetus via the placenta and before the onset of marked erythropoietic activity of fetal marrow during the third trimester. Soon after preterm birth, severe respiratory disease can lead to repeated blood sampling for laboratory studies and, consequently, to replacement RBC transfusions. Additionally, preterm infants are unable to mount an effective erythropoietin (EPO) response to decreasing numbers of RBCs, and this factor contributes to the diminished ability to compensate for anemia—thus enhancing need for RBC transfusions. PMID:18194380

Toll-like Receptor-4: A New Target for Preterm Labour Pharmacotherapies?

PubMed

Robertson, Sarah A; Wahid, Hanan H; Chin, Peck Yin; Hutchinson, Mark R; Moldenhauer, Lachlan M; Keelan, Jeffrey A

2018-01-01

Inflammatory activation, a major driver of preterm birth and subsequent neonatal morbidity, is an attractive pharmacological target for new preterm birth therapeutics. Inflammation elicited by intraamniotic infection is causally associated with preterm birth, particularly in infants delivered ≤34 weeks' gestation. However, sterile triggers of PTB, including placental ischaemic injury, uterine distention, cervical disease, or imbalance in the immune response, also act through inflammatory mediators released in response to tissue damage. Toll-like Receptors (TLRs) are critical upstream gate-keepers controlling the inflammatory activation that precedes preterm delivery, as well as in normal term labour. In particular, TLR4 is implicated for its capacity to sense and integrate a range of disparate infectious and sterile pro-inflammatory triggers, and so acts as a point-ofconvergence through which a range of infectious and sterile agents can activate and accelerate the parturition cascade. Recent studies point to the TLR4 signalling complex as a tractable target for the inhibition of fetal, placental & intraamniotic inflammatory cytokine production. Moreover, studies on mice show that novel small molecule antagonists of TLR4 signalling are highly effective in preventing preterm birth induced by bacterial mimetic LPS, heat-killed E. coli or the TLR4-dependent pro-inflammatory lipid, Platelet Activating Factor (PAF). In this review, we discuss the role of TLR4 in regulating the timing of birth and the potential utility of TLR4 antagonists as novel therapeutics for preterm delivery. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

[Risk factors associated with preterm birth in a second level hospital].

PubMed

Escobar-Padilla, Beatriz; Gordillo-Lara, Limberg Darinel; Martínez-Puon, Horacio

2017-01-01

Preterm birth is one of the biggest problems in obstetrics and gynecology, given that it has an incidence of 10-11%. The objective was to identify the risk factors associated with a preterm birth. A retrospective, observational, transversal and analytic case-control study was made. All premature birth incidences were determined as study objects and controls were integrated with term deliveries. A sample size of 344 patients with a control per case was calculated. A total of 688 patients were studied. Statistical analysis was descriptive, univariate and bivariate and we used the Pearson chi square test, with a p < 0.05, odds ratios (OR) and 95% confidence intervals (95% CI). The risk factors associated with a preterm labor were placenta praevia: OR = 10.2 (p = 0.005); previous preterm delivery: OR = 10.2 (p = 0.005); preeclampsia: OR = 6.38 (p = 0.00); twin pregnancy: OR = 5.8 (p = 0.000); oligohydramnios: OR = 5.8 (p = 0.000); tobacco use: OR = 4.6 (p = 0.002); premature rupture of membranes (PROM): OR = 4.1 (p = 0.000); cervicovaginitis: OR = 3 (p = 0.000); urinary tract infections (UTI): OR = 1.5 (p = 0.010). Maternal history of prenatal care, preclampsia, PROM, twin pregnancy, placenta praevia, cervicovaginitis, previous preterm delivery and UTI are risk factors with statistical significance associated with preterm delivery.

Breathing patterns in preterm and term infants immediately after birth.

PubMed

te Pas, Arjan B; Wong, Connie; Kamlin, C Omar F; Dawson, Jennifer A; Morley, Colin J; Davis, Peter G

2009-03-01

There is limited data describing how preterm and term infants breathe spontaneously immediately after birth. We studied spontaneously breathing infants >or=29 wk immediately after birth. Airway flow and tidal volume were measured for 90 s using a hot wire anemometer attached to a facemask. Twelve preterm and 13 term infants had recordings suitable for analysis. The median (interquartile range) proportion of expiratory braking was very high in both groups (preterm 90 [74-99] vs. term 87 [74-94]%; NS). Crying pattern was the predominant breathing pattern for both groups (62 [36-77]% vs. 64 [46-79]%; NS). Preterm infants showed a higher incidence of expiratory hold pattern (9 [4-17]% vs. 2 [0-6]%; p = 0.02). Both groups had large tidal volumes (6.7 [3.9] vs. 6.5 [4.1] mL/kg), high peak inspiratory flows (5.7 [3.8] vs. 8.0 [5] L/min), lower peak expiratory flow (3.6 [2.4] vs. 4.8 [3.2] L/min), short inspiration time (0.31 [0.13] vs. 0.32 [0.16] s) and long expiration time (0.93 [0.64] vs. 1.14 [0.86] s). Directly after birth, both preterm and term infants frequently brake their expiration, mostly by crying. Preterm infants use significantly more expiratory breath holds to defend their lung volume.

Continuous versus bolus intragastric tube feeding for preterm and low birth weight infants with gastro-oesophageal reflux disease.

PubMed

Richards, Robyn; Foster, Jann P; Psaila, Kim

2014-07-17

Gastro-oesophageal reflux disease is a particularly common condition in preterm and low birth weight infants. These infants are also more likely to have excessive regurgitation, as they do not have a fully developed antireflux mechanism. Preterm and low birth weight infants who are unable to suck oral feeds are required to be fed via an intragastric tube for varying lengths of time. Intragastric tube feeding can be delivered by the intermittent bolus or continuous feeding method. Use of continuous or intermittent bolus intragastric feeding may have a positive or negative effect on the incidence or severity of gastro-oesophageal reflux disease. To determine whether continuous or intermittent bolus intragastric tube feeding reduces the number of episodes and the duration of gastro-oesophageal reflux disease (GORD) in preterm and low birth weight infants.We intended to perform subgroup analyses for gestational age; birth weight; age in days from birth at full enteral feeding via intragastric tube (breast vs bottle); frequency of intermittent bolus feed; and type of medication for treatment of GORD (only if medication prescribed and given similarly to both intervention groups). We used the standard search strategy of the Cochrane Neonatal Group as described in The Cochrane Library (www.thecochranelibrary.com) to search for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 9), MEDLINE (1966 to September 2013), EMBASE (1980 to September 2013) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to September 2013). We also searched previous reviews, including cross-references, abstracts and conference and symposia proceedings of the Perinatal Society of Australia and New Zealand and the Pediatric Academic Societies (American Pediatric Society/Society for Pediatric Research and European Society for Paediatric Research) from 1990 to 2012. Published and unpublished RCTs and quasi-RCTs were eligible for inclusion in this review, as were cluster-randomised and cross-over randomised trials that compared the effects of continuous versus intermittent bolus intragastric tube feeding on gastro-oesophageal reflux disease in preterm and low birth weight infants. Two review authors independently assessed study eligibility and quality. We found no trials that met the inclusion criteria for this review. We did not identify any randomised trials that evaluated the effects of continuous versus intermittent bolus intragastric tube feeding on gastro-oesophageal reflux disease in preterm and low birth weight infants. Well-designed and adequately powered trials are needed.

Attention Problems in Very Preterm Children from Childhood to Adulthood: The Bavarian Longitudinal Study

ERIC Educational Resources Information Center

Breeman, Linda D.; Jaekel, Julia; Baumann, Nicole; Bartmann, Peter; Wolke, Dieter

2016-01-01

Background: Very preterm (VP; gestational age <32 weeks) and very low birth weight (VLBW; <1500 grams) is related to attention problems in childhood and adulthood. The stability of these problems into adulthood is not known. Methods: The Bavarian Longitudinal Study is a prospective cohort study that followed 260 VP/VLBW and 229 term-born…

Modification of the effect of ambient air pollution on pediatric asthma emergency visits: susceptible subpopulations

PubMed Central

Strickland, Matthew J; Klein, Mitchel; Flanders, W Dana; Chang, Howard H; Mulholland, James A; Tolbert, Paige E; Darrow, Lyndsey A

2016-01-01

Background Children may have differing susceptibility to ambient air pollution concentrations depending on various background characteristics of the children. Methods Using emergency department (ED) data linked with birth records from Atlanta, Georgia, we identified ED visits for asthma or wheeze among children aged 2–16 years from 1 January 2002 through 30 June 2010 (n=109,758). We stratified by preterm delivery, term low birth weight, maternal race, Medicaid status, maternal education, maternal smoking, delivery method, and history of a bronchiolitis ED visit. Population-weighted daily average concentrations were calculated for 1-hour maximum carbon monoxide and nitrogen dioxide; 8-hour maximum ozone; and 24-hour average particulate matter less than 10 microns in diameter, particulate matter less than 2.5 microns in diameter (PM2.5), and the PM2.5 components sulfate, nitrate, ammonium, elemental carbon, and organic carbon, using measurements from stationary monitors. Poisson time-series models were used to estimate rate ratios for associations between three-day moving average pollutant concentrations and daily ED visit counts and to investigate effect-measure modification by the stratification factors. Results Associations between pollutant concentrations and asthma exacerbations were larger among children born preterm and among children born to African American mothers. Stratification by race and preterm status together suggested that both factors affected susceptibility. The largest estimated effect size (for an interquartile-range increase in pollution) was observed for ozone among preterm births to African American mothers: rate ratio=1.138 (95% confidence interval=1.077–1.203). In contrast, the rate ration for the ozone association among full-term births to mothers of other races was 1.025 (0.970–1.083). Conclusions Results support the hypothesis that children vary in their susceptibility to ambient air pollutants. PMID:25192402

Preterm (Premature) Labor and Birth

MedlinePlus

... with serious health problems. Some health problems, like cerebral palsy , can last a lifetime. Other problems, such as ... This medication may help reduce the risk of cerebral palsy that is associated with early preterm birth. What ...

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.

Postnatal epigenetic modification of glucocorticoid receptor gene in preterm infants: a prospective cohort study

PubMed Central

Kantake, Masato; Yoshitake, Hiroshi; Ishikawa, Hitoshi; Araki, Yoshihiko; Shimizu, Toshiaki

2014-01-01

Objective To examine the environmental effects on cytosine methylation of preterm infant's DNA, because early life experiences are considered to influence the physiological and mental health of an individual through epigenetic modification of DNA. Design A prospective cohort study, comparison of epigenetic differences in the glucocorticoid receptor (GR) gene between healthy term and preterm infants. Setting Neonatal Intensive Care Unit in a Japanese University Hospital. Participants A cohort of 40 (20 term and 20 preterm) infants was recruited on the day of birth, and peripheral blood was obtained from each infant at birth and on postnatal day 4. Main outcome measures The methylation rates in the 1-F promoter region of the GR gene using the Mquant method. Results The methylation rate increased significantly between postnatal days 0 and 4 in preterm infants but remained stable in term infants. Thus, the methylation rate was significantly higher in preterm than in term infants at postnatal day 4. Several perinatal parameters were significantly correlated with this change in the methylation rate. Logistic regression analysis revealed that methylation rates at postnatal day 4 predicted the occurrence of later complications that required glucocorticoid administration during the neonatal period. No gene polymorphism was detected within the GR promoter region analysed. Conclusions Although further large-scale studies are needed to detect the environmental factors that explain the difference in epigenetic modification among infants after birth, our data show that the postnatal environment influences epigenetic programming of GR expression through methylation of the GR gene promoter in premature infants, which may result in relative glucocorticoid insufficiency during the postnatal period. PMID:25023132

Association between maternal periodontal disease and preterm delivery and low birth weight.

PubMed

Wang, Yen-Li; Liou, Jui-Der; Pan, Whei-Lin

2013-03-01

It has been suggested that periodontal disease is an important risk factor for preterm low birth weight (PLBW). The purpose of this study was to determine the association of maternal periodontitis with low birth weight (LBW) and preterm birth (PB). Pregnant women (n = 211) aged 22-40 years were enrolled while receiving prenatal care. Dental plaque, probing depth, bleeding on probing, and clinical attachment level were used as criteria to classify three groups: a healthy group (HG; n = 82), a gingivitis group (GG; n = 67), and a periodontitis group (PG; n = 62). At delivery, birth weight was recorded. Mean infant weight at delivery was 3084.9 g. The total incidence of preterm birth and LBW infants was 10.4% and 8.1%, respectively. The incidence of LBW infants was 4.2% for term and 40.9% for preterm gestations. Maternal height was not correlated with infant birth weight (p = 0.245). Significant differences in mean infant birth weight were observed among the HG, GG, and PG groups (p = 0.030). No significant relationship was found between periodontal disease and PB, but the association between periodontal disease and LBW was significant. After appropriately controlling for confounding variables, our results do not support the hypothesis of an association that was observed in previous studies of maternal periodontal disease and infant PB, but the association between periodontal disease and LBW is significant. Copyright © 2013. Published by Elsevier B.V.

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

'Resuscitation' of extremely preterm and/or low-birth-weight infants - time to 'call it'?

PubMed

O'Donnell, Colm P F

2008-01-01

Since ancient times, various methods have been used to revive apparently stillborn infants; many were of dubious efficacy and had the potential to cause harm. Based largely on studies of acutely asphyxiated term animal models, clinical assessment and positive pressure ventilation have become the cornerstones of neonatal resuscitation over the last 40 years. Over the last 25 years, care of extremely preterm infants in the delivery room has evolved from a policy of indifference to one of increasingly aggressive support. The survival of these infants has improved considerably in recent years; this has not, however, necessarily been due to more aggressive resuscitation. Urban myths have evolved that all extremely preterm infants died before they were intubated, and that all such infants need to immediately intubated or they will quickly die. This has never been true. Clinical assessment of infants at birth is subjective. Also, many techniques used to support preterm infants at birth have not been well studied and there is evidence that they may be harmful. It may thus be argued that many of our well-intentioned resuscitation interventions are of dubious efficacy and have the potential to cause harm. 'Resuscitation' is an emotive term which means 'restoration of life'. Death, thankfully, is a rare presentation in the delivery room. Therefore, concerning neonatal 'resuscitation', it is time to 'call it' something else. This will allow us to dispassionately distinguish preterm infants who are dead, or nearly dead, from those who are merely at high risk of parenchymal lung disease. We may then be able to refine our interventions and determine what methods of support benefit these infants most. (c) 2008 S. Karger AG, Basel.

Mortality in the first 24h of very low birth weight preterm infants in the Northeast of Brazil

PubMed Central

de Castro, Eveline Campos Monteiro; Leite, Álvaro Jorge Madeiro; Guinsburg, Ruth

2016-01-01

Abstract Objective: To evaluate factors associated with neonatal death within 24 hours after birth in very low birth weight preterm newborns. Methods: Prospective cohort of live births with gestational age of 230/7–316/7 weeks, birth weight of 500–1499g without malformations, in 19 public maternity hospitals in nine capitals in northeastern Brazil from July to December 2007. The 19 hospitals were assessed in relation to physical resources, equipment, human resources and aiming at quality in care initiatives. Hospital, maternal and neonatal characteristics, neonatal morbidity, neonatal procedures and interventions were compared between preterm newborns that died or survived up to 24 hours of life. The variables associated with death within 24 hours after birth were determined by logistic regression. Results: Of the 627 newborns enrolled in the study, 179 (29%) died within 168 hours after birth, of which 59 (33%) up to 24 hours and 97 (54%) up to 48 hours after birth. The variables associated with death <24h were: weight <1000g (2.94; 1.32–6.53), 5th minute Apgar <7 (7.17; 3.46–14.88), male gender (2.99; 1.39–6.47). A better hospital structure was a protective factor for early neonatal death (odds ratio: 0.34; 95% confidence interval: 0.17–0.71). Conclusions: The high neonatal mortality on the first day of life in capital cities of Northeast Brazil is associated with biological variables such as weight and gender of the newborn, as well as low vitality at birth and a worse infrastructure of the hospital where the birth occurred. PMID:26726002

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.

Pregnant Women in Sport Climbing - Is there a Higher Risk for Preterm Birth?

PubMed

Drastig, Jan; Hillebrandt, David; Rath, Werner; Küpper, Thomas

2017-02-01

Sport climbing is a popular recreational sport with an increasing proportion of female athletes. International recommendations emphasize the physical and mental benefits of regular sport activity during any uncomplicated pregnancy. In this context, sport climbing is associated with a high risk potential.The aim of this study was to examine if there is a higher risk for preterm birth in active climbing athletes.Original manuscript.A retrospective self-report online survey in the German language collected data between September 2012 and November 2013. In addition to anthropometric and demographic data, data on climbing experience, preferred climbing discipline, skill level and changes of climbing habits during pregnancy, known risk factors for preterm birth and information on delivery and the newborn were requested. The rate of preterm birth of the survey was tested with Fisher's exact test with information from the German Federal Statistical Office.Sample size was 32. 72% had a university degree, 81% were primiparous, all were singleton pregnancies. A 33 rd questionnaire was excluded because of described preeclampsia. Age ranged between 21 and 39 years, climbing experience before pregnancy between 2 and 24 years, and skill level before pregnancy between 4 and 7 on the UIAA scale (International Climbing and Mountaineering Federation). Half of the women climbed until the 36 th week and 90% adjusted their climbing habits mostly by reducing climbing difficulty and doing more top roping. 2 preterm births in the 36 th week of gestation were found (2 from 15, p=0.36). According to the data from the German Federal Statistical Office, 8.9% births in the year 2013 in Germany were preterm.This is the first study investigating the risk of preterm birth in recreational sport climbing athletes. No significantly higher proportion of preterm birth could be found. Limitations are small sample size and high social status of participants. What is known about the subject: Sport climbing is not a high-risk sport, but it is regarded as a dynamic whole-body exercise and has been shown to be a valuable therapy for various physical and mental diseases. Higher performance levels are associated with overuse damage to the upper extremity, especially the fingers. What this study adds to existing knowledge: This is first study investigating climbing-related risk of preterm birth. When continuing sport climbing as a recreational activity during an uncomplicated pregnancy, experienced athletes do not have a higher risk of adverse events. © Georg Thieme Verlag KG Stuttgart · New York.

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.

A Role for the Liver in Parturition and Preterm Birth.

PubMed

Mawson, Anthony R

Neither the mechanisms of parturition nor the pathogenesis of preterm birth are well understood. Poor nutritional status has been suspected as a major causal factor, since vitamin A concentrations are low in preterm infants. However, even large enteral doses of vitamin A from birth fail to increase plasma concentrations of vitamin A or improve outcomes in preterm and/or extremely low birthweight infants. These findings suggest an underlying impairment in the secretion of vitamin A from the liver, where about 80% of the vitamin is stored. Vitamin A accumulates in the liver and breast during pregnancy in preparation for lactation. While essential in low concentration for multiple biological functions, vitamin A in higher concentration can be pro-oxidant, mutagenic, teratogenic and cytotoxic, acting as a highly surface-active, membrane-seeking and destabilizing compound. Regarding the mechanism of parturition, it is conjectured that by nine months of gestation the hepatic accumulation of vitamin A (retinol) from the liver is such that mobilization and secretion are impaired to the point where stored vitamin A compounds in the form of retinyl esters and retinoic acid begin to spill or leak into the circulation, resulting in amniotic membrane destabilization and the initiation of parturition. If, however, the accumulation and spillage of stored retinoids reaches a critical threshold prior to nine months, e.g., due to cholestatic liver disease, which is common in mothers of preterm infants, the increased retinyl esters and/or retinoic acid rupture the fetal membranes, inducing preterm birth and its complications, including retinopathy, necrotizing enterocolitis and bronchopulmonary dysplasia. Subject to testing, the model suggests that measures taken prior to and during pregnancy to improve liver function could reduce the risk of adverse birth outcomes, including preterm birth.

A Role for the Liver in Parturition and Preterm Birth

PubMed Central

Mawson, Anthony R.

2016-01-01

Neither the mechanisms of parturition nor the pathogenesis of preterm birth are well understood. Poor nutritional status has been suspected as a major causal factor, since vitamin A concentrations are low in preterm infants. However, even large enteral doses of vitamin A from birth fail to increase plasma concentrations of vitamin A or improve outcomes in preterm and/or extremely low birthweight infants. These findings suggest an underlying impairment in the secretion of vitamin A from the liver, where about 80% of the vitamin is stored. Vitamin A accumulates in the liver and breast during pregnancy in preparation for lactation. While essential in low concentration for multiple biological functions, vitamin A in higher concentration can be pro-oxidant, mutagenic, teratogenic and cytotoxic, acting as a highly surface-active, membrane-seeking and destabilizing compound. Regarding the mechanism of parturition, it is conjectured that by nine months of gestation the hepatic accumulation of vitamin A (retinol) from the liver is such that mobilization and secretion are impaired to the point where stored vitamin A compounds in the form of retinyl esters and retinoic acid begin to spill or leak into the circulation, resulting in amniotic membrane destabilization and the initiation of parturition. If, however, the accumulation and spillage of stored retinoids reaches a critical threshold prior to nine months, e.g., due to cholestatic liver disease, which is common in mothers of preterm infants, the increased retinyl esters and/or retinoic acid rupture the fetal membranes, inducing preterm birth and its complications, including retinopathy, necrotizing enterocolitis and bronchopulmonary dysplasia. Subject to testing, the model suggests that measures taken prior to and during pregnancy to improve liver function could reduce the risk of adverse birth outcomes, including preterm birth. PMID:27595011

Estimation of birth population-based perinatal-neonatal mortality and preterm rate in China from a regional survey in 2010.

PubMed

Sun, L; Yue, H; Sun, B; Han, L; Qi, M; Tian, Z; Lu, S; Shan, C; Luo, J; Fan, Y; Li, S; Dong, M; Zuo, X; Zhang, Y; Lin, W; Xu, J; Heng, Y

2013-11-01

To estimate birth population-based perinatal-neonatal mortality and preterm rate in China from a regional survey in 2010. Data of total births in 2010 obtained from 151 level I-III hospitals in Huai'an, Jiangsu, were prospectively collected and analyzed. From 61,227 birth registries (including 60,986 live births and 241 stillbirths), we derive a birth rate of 11.3‰ (of 5.4 million regional population), a male-to-female ratio of 116:100 and valid data from 60,615 newborns. Mean birth weight (BW) was 3441 ± 491 g with 13.6% macrosomia. Low BW was 2.8% (1691/60,372) with 8.83% mortality. Preterm rate was 3.72% (2239/60,264) with 7.61% mortality. Cesarean section rate was 52.9% (31,964/60,445), multiple pregnancy 1.8% (1088/60,567) and birth defects 6.7‰ (411/61,227). There were 97.4% healthy newborns and 2.2% (1298) requiring hospitalized after birth. The perinatal mortality was 7.7‰ (471/61,227, including 241 stillbirths, 230 early neonatal deaths). The neonatal mortality was 4.4‰ (269/60,986). The main causes of neonatal death were birth asphyxia (24.5%), respiratory diseases (21.5%), prematurity related organ dysfunction (18.5%) and congenital anomalies (7.7%), whereas incidence of congenital heart disease and respiratory distress syndrome was 8.6‰ and 6.1‰, respectively. This regional birth population-based data file contains low perinatal-neonatal mortality rates, associated with low proportion of LBW and preterm births, and incidences of major neonatal disease, by which we estimate, in a nationwide perspective, in 16 million annual births, preterm births should be around 800,000, perinatal and neonatal mortality may be 128,000-144,000 and 80,000-96,000, respectively, along with 100,000 respiratory distress syndrome.

Prematurity and low weight at birth as new conditions predisposing to an increased cardiovascular risk.

PubMed

Mercuro, Giuseppe; Bassareo, Pier Paolo; Flore, Giovanna; Fanos, Vassilios; Dentamaro, Ilaria; Scicchitano, Pietro; Laforgia, Nicola; Ciccone, Marco Matteo

2013-04-01

Although the survival rate for preterm subjects has improved considerably, due to the progress in the field of perinatal medicine, preterm birth is frequently the cause underlying a series of notorious complications: morphological, neurological, ophthalmological, and renal alterations. In addition, it has recently been demonstrated how low gestational age and reduced foetal growth contribute towards an increased cardiovascular risk in preterm neonates. In fact, cardiovascular mortality is higher among former preterm adults than those born at term. This condition is referred to as cardiovascular perinatal programming. In the light of the above, an early, constant, and prolonged cardiological followup programme should be implemented in former preterm individuals. The aim of this paper was to perform a comprehensive literature review about two new emerging conditions predisposing to an increased cardiovascular risk: prematurity and low weight at birth.

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.

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.

Neighborhood deprivation and preterm birth among non-Hispanic black and white women in eight geographic areas in the United States

EPA Science Inventory

Disparities in preterm birth by race and ethnic group have been demonstrated in the United States. Recent research focuses on the impact of neighborhood environmental context on racial disparities in pregnancy outcomes. The authors utilized vital records birth certificate and...

Hot Executive Function Following Moderate-to-Late Preterm Birth: Altered Delay Discounting at 4 Years of Age

ERIC Educational Resources Information Center

Hodel, Amanda S.; Brumbaugh, Jane E.; Morris, Alyssa R.; Thomas, Kathleen M.

2016-01-01

Interest in monitoring long-term neurodevelopmental outcomes of children born moderate-to-late preterm (32-36 weeks gestation) is increasing. Moderate-to-late preterm birth has a negative impact on academic achievement, which may relate to differential development of executive function (EF). Prior studies reporting deficits in EF in preterm…

Visual Perception and Visual-Motor Integration in Very Preterm and/or Very Low Birth Weight Children: A Meta-Analysis

ERIC Educational Resources Information Center

Geldof, C. J. A.; van Wassenaer, A. G.; de Kieviet, J. F.; Kok, J. H.; Oosterlaan, J.

2012-01-01

A range of neurobehavioral impairments, including impaired visual perception and visual-motor integration, are found in very preterm born children, but reported findings show great variability. We aimed to aggregate the existing literature using meta-analysis, in order to provide robust estimates of the effect of very preterm birth on visual…

Use of progesterone and progestin analogs for inhibition of preterm birth and other uterine contractility disorders

PubMed Central

Garfield, R.E.; Shi, L.; Shi, S-Q.

2012-01-01

In this paper we focus on preterm birth as a uterine contractility disorder caused by hypercontractility of the myometrium. We describe changes in uterine function during term and preterm labor and delivery. We also examine the usefulness of measurement of uterine electromyographic (EMG) activity, noninvasively monitored from the abdominal surface of pregnant patients. The use of progesterone treatment for preterm birth is discussed and we conclude that present therapies with progesterone could be improved by changing the route of administration. Finally we show the results of recent studies that show that progesterone injections completely inhibit uterine EMG activity when given several days to hours before normal delivery. These studies illustrate how progesterone suppresses labor at term or preterm, probably through repression of genes which control excitability and conduction of electrical activity. However, direct profusion of soluble progesterone into the uterine cavity has little immediate inhibitory action and this may demonstrate that progesterone has no direct, nongenomic effects, at least in the rat model used. Further studies are required to determine the effects of progesterone on human uterine EMG activity and whether progesterone treatments will prevent preterm birth. PMID:24753915

SOCIODEMOGRAPHIC DOAMINS OF DEPRIVATION AND PRETERM BIRTH

EPA Science Inventory

Background. Neighborhood-level deprivation has long been associated with adverse outcomes, including preterm birth (PTB), as observed in the authors' previous work using a composite deprivation index. Area disadvantage is multifaceted comprising income, employment, education and...

Cervical HSV-2 infection causes cervical remodeling and increases risk for ascending infection and preterm birth.

PubMed

McGee, Devin; Smith, Arianna; Poncil, Sharra; Patterson, Amanda; Bernstein, Alison I; Racicot, Karen

2017-01-01

Preterm birth (PTB), or birth before 37 weeks gestation, is the leading cause of neonatal mortality worldwide. Cervical viral infections have been established as risk factors for PTB in women, although the mechanism leading to increased risk is unknown. Using a mouse model of pregnancy, we determined that intra-vaginal HSV2 infection caused increased rates of preterm birth following an intra-vaginal bacterial infection. HSV2 infection resulted in histological changes in the cervix mimicking cervical ripening, including significant collagen remodeling and increased hyaluronic acid synthesis. Viral infection also caused aberrant expression of estrogen and progesterone receptor in the cervical epithelium. Further analysis using human ectocervical cells demonstrated a role for Src kinase in virus-mediated changes in estrogen receptor and hyaluronic acid expression. In conclusion, HSV2 affects proteins involved in tissue hormone responsiveness, causes significant changes reminiscent of premature cervical ripening, and increases risk of preterm birth. Studies such as this improve our chances of identifying clinical interventions in the future.

Cervical HSV-2 infection causes cervical remodeling and increases risk for ascending infection and preterm birth

PubMed Central

McGee, Devin; Poncil, Sharra; Patterson, Amanda

2017-01-01

Preterm birth (PTB), or birth before 37 weeks gestation, is the leading cause of neonatal mortality worldwide. Cervical viral infections have been established as risk factors for PTB in women, although the mechanism leading to increased risk is unknown. Using a mouse model of pregnancy, we determined that intra-vaginal HSV2 infection caused increased rates of preterm birth following an intra-vaginal bacterial infection. HSV2 infection resulted in histological changes in the cervix mimicking cervical ripening, including significant collagen remodeling and increased hyaluronic acid synthesis. Viral infection also caused aberrant expression of estrogen and progesterone receptor in the cervical epithelium. Further analysis using human ectocervical cells demonstrated a role for Src kinase in virus-mediated changes in estrogen receptor and hyaluronic acid expression. In conclusion, HSV2 affects proteins involved in tissue hormone responsiveness, causes significant changes reminiscent of premature cervical ripening, and increases risk of preterm birth. Studies such as this improve our chances of identifying clinical interventions in the future. PMID:29190738

The outcome of pregnancy after threatened abortion.

PubMed

Hertz, J B; Heisterberg, L

1985-01-01

A prospectively collected group of 93 pregnancies complicated by threatened abortion was carefully monitored throughout pregnancy, during birth and in the perinatal period, and any deviation from a completely uneventful course was registered. Comparison was made with a selected group of 282 non-risk pregnant women. A significant association was found between threatened abortion and the overall number of complications in the second half of pregnancy requiring medical intervention and/or admission to hospital, impending pre-term birth requiring betamimetics, pre-term birth, retention of the placenta, birth weight below 2000 g, light-for-dates infants in case of pre-term birth or birth weight below 2000 g, and hyperbilirubinemia in infants with birth weight below 2000 g. The incidences of perinatal mortality and congenital malformations did not differ significantly from those of the control group. Pregnancies complicated by threatened abortion constitute a risk group requiring careful obstetric and perinatal supervision and follow-up.

Preterm birth and low birth weight continue to increase the risk of asthma from age 7 to 43.

PubMed

Matheson, Melanie C; D Olhaberriague, Ana López-Polín; Burgess, John A; Giles, Graham G; Hopper, John L; Johns, David P; Abramson, Michael J; Walters, E Haydn; Dharmage, Shyamali C

2017-08-01

Perinatal events can influence the development of asthma in childhood but current evidence is contradictory concerning the effects on life-time asthma risk. To assess the relationship between birth characteristics and asthma from childhood to adulthood. All available birth records for the Tasmanian Longitudinal Health Study (TAHS) cohort, born in 1961 were obtained from the Tasmanian State Archives and Tasmanian hospitals. Low birth weight (LBW) was defined as less than 2500 grams. Preterm birth was defined as delivery before 37 weeks' gestation. Small for gestational age (SGA) was defined as a birth weight below the 10 th percentile for a given gestational age. Multivariate logistic and cox regression were used to examine associations between birth characteristics and lifetime risk of current and incident asthma, adjusting for confounders. The prevalence of LBW was 5.2%, SGA was 13.8% and preterm was 3.3%. LBW (OR = 1.65, 95%CI 1.12,2.44) and preterm birth (OR = 1.81, 95%CI 0.99, 3.31) were both associated with an increased risk of current asthma between the ages of 7 to 43 years. There was no association between SGA and current asthma risk. However, SGA was associated with incident asthma (HR = 1.32, 95%CI 1.00, 1.74), and there was an interaction with sex (p value = 0.08), with males having a greater risk of incident asthma (HR = 1.70, 95%CI 1.16-2.49) than females (HR = 1.04, 95%CI 0.70-1.54). Preterm birth and LBW were associated with an increased risk of current asthma into middle-age. These findings are the first to demonstrate the continuing impact of these characteristics on asthma risk into middle-age.

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

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.

Relationship between Revised Graduated Index (R-GINDEX) of prenatal care utilization & preterm labor and low birth weight.

PubMed

Tayebi, Tahereh; Hamzehgardeshi, Zeinab; Ahmad Shirvani, Marjan; Dayhimi, Marjaneh; Danesh, Mahmonir

2014-02-28

Prenatal care refers to accurate and consistent performance of the principles important to maintain healthy pregnancy outcomes and also for mother and child health. One of the new indices to assess the adequacy of care is Revised Graduated Index of Prenatal Care Utilization (R-GINDEX).The study aims to assess the relationship between quantitative prenatal care factors and preterm labor and low birth weight using R-GINDEX. This historical cohort study has been conducted on 420 mothers during the first two years after delivery in 2010. The adequacy of care was calculated by R-GINDEX. Based on this index, participants have been divided into three care groups including inadequate, adequate and intensive care groups. A significant relationship has been found between R-GINDEX and preterm birth and low birth weight (P<0.05). Thus the probability of premature labor in inadequate care group (RR=3.93) and low birth weight (RR= 2.53) was higher than that of the adequate and intensive care group. The results showed that the quantity of prenatal care is effective in reducing preterm birth and low birth weight.

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, 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.

Growth after late-preterm birth and adult cognitive, academic, and mental health outcomes.

PubMed

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

2017-05-01

Late-preterm birth (at 34 0⁄7 -36 6⁄7 wk gestation) increases the risk of early growth faltering, poorer neurocognitive functioning, and lower socio-economic attainment. Among early-preterm individuals, faster early growth benefits neurodevelopment, but it remains unknown whether these benefits extend to late-preterm individuals. In 108 late-preterm individuals, we examined if weight, head, or length growth between birth, 5 and 20 months' corrected age, and 56 mo, predicted grade point average and special education in comprehensive school, or neurocognitive abilities and psychiatric diagnoses/symptoms at 24-26 y of age. For every 1 SD faster weight and head growth from birth to 5 mo, and head growth from 5 to 20 mo, participants had 0.19-0.41 SD units higher IQ, executive functioning score, and grade point average (95% confidence intervals (CI) 0.002-0.59 SD), and lower odds of special education (odds ratio (OR) = 0.49-0.59, 95% CIs 0.28-0.97), after adjusting for sex, gestational age, follow-up age, and parental education. Faster head growth from 20 to 56 mo was associated with less internalizing problems; otherwise we found no consistent associations with mental health outcomes. Faster growth during the critical early period after late-preterm birth is associated with better adult neurocognitive functioning, but not consistently with mental health outcomes.

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.

The economic burden of prematurity in Canada.

PubMed

Johnston, Karissa M; Gooch, Katherine; Korol, Ellen; Vo, Pamela; Eyawo, Oghenowede; Bradt, Pamela; Levy, Adrian

2014-04-05

Preterm birth is a major risk factor for morbidity and mortality among infants worldwide, and imposes considerable burden on health, education and social services, as well as on families and caregivers. Morbidity and mortality resulting from preterm birth is highest among early (< 28 weeks gestational age) and moderate (28-32 weeks) preterm infants, relative to late preterm infants (33-36 weeks). However, substantial societal burden is associated with late prematurity due to the larger number of late preterm infants relative to early and moderate preterm infants. The aim in this study was to characterize the burden of premature birth in Canada for early, moderate, and late premature infants, including resource utilization, direct medical costs, parental out-of-pocket costs, education costs, and mortality, using a validated and published decision model from the UK, and adapting it to a Canadian setting based on analysis of administrative, population-based data from Québec. Two-year survival was estimated at 56.0% for early preterm infants, 92.8% for moderate preterm infants, and 98.4% for late preterm infants. Per infant resource utilization consistently decreased with age. For moderately preterm infants, hospital days ranged from 1.6 at age two to 0.09 at age ten. Cost per infant over the first ten years of life was estimated to be $67,467 for early preterm infants, $52,796 for moderate preterm infants, and $10,010 for late preterm infants. Based on population sizes this corresponds to total national costs of $123.3 million for early preterm infants, $255.6 million for moderate preterm infants, $208.2 million for late preterm infants, and $587.1 million for all infants. Premature birth results in significant infant morbidity, mortality, healthcare utilization and costs in Canada. A comprehensive decision-model based on analysis of a Canadian population-based administrative data source suggested that the greatest national-level burden is associated with moderate preterm infants due to both a large cost per infant and population size while the highest individual-level burden is in early preterm infants and the largest total population size is in late preterm infants. Although the highest medical costs are incurred during the neonatal period, greater resource utilization and costs extend into childhood.

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.

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.

Urinary Bisphenol A Levels during Pregnancy and Risk of Preterm Birth

PubMed Central

Ferguson, Kelly K.; Mukherjee, Bhramar; McElrath, Thomas F.; Meeker, John D.

2015-01-01

Background Preterm birth (PTB), a leading cause of infant mortality and morbidity, has a complex etiology with a multitude of interacting causes and risk factors. The role of environmental contaminants, particularly bisphenol A (BPA), is understudied with regard to PTB. Objectives In the present study we examined the relationship between longitudinally measured BPA exposure during gestation and PTB. Methods A nested case–control study was performed from women enrolled in a prospective birth cohort study at Brigham and Women’s Hospital in Boston, Massachusetts, during 2006–2008. Urine samples were analyzed for BPA concentrations at a minimum of three time points during pregnancy on 130 cases of PTB and 352 randomly assigned controls. Clinical classifications of PTB were defined as “spontaneous,” which was preceded by spontaneous preterm labor or preterm premature rupture of membranes, or “placental,” which was preceded by preeclampsia or intrauterine growth restriction. Results Geometric mean concentrations of BPA did not differ significantly between cases and controls. In adjusted models, urinary BPA averaged across pregnancy was not significantly associated with PTB. When examining clinical classifications of PTB, urinary BPA late in pregnancy was significantly associated with increased odds of delivering a spontaneous PTB. After stratification on infant’s sex, averaged BPA exposure during pregnancy was associated with significantly increased odds of being delivered preterm among females, but not males. Conclusions These results provide little evidence of a relationship between BPA and prematurity, though further research may be warranted given the generalizability of participant recruitment from a tertiary teaching hospital, limited sample size, and significant associations among females and within the clinical subcategories of PTB. Citation Cantonwine DE, Ferguson KK, Mukherjee B, McElrath TF, Meeker JD. 2015. Urinary bisphenol A levels during pregnancy and risk of preterm birth. Environ Health Perspect 123:895–901; http://dx.doi.org/10.1289/ehp.1408126 PMID:25815860

Screening to prevent spontaneous preterm birth: systematic reviews of accuracy and effectiveness literature with economic modelling.

PubMed

Honest, H; Forbes, C A; Durée, K H; Norman, G; Duffy, S B; Tsourapas, A; Roberts, T E; Barton, P M; Jowett, S M; Hyde, C J; Khan, K S

2009-09-01

To identify combinations of tests and treatments to predict and prevent spontaneous preterm birth. Searches were run on the following databases up to September 2005 inclusive: MEDLINE, EMBASE, DARE, the Cochrane Library (CENTRAL and Cochrane Pregnancy and Childbirth Group trials register) and MEDION. We also contacted experts including the Cochrane Pregnancy and Childbirth Group and checked reference lists of review articles and papers that were eligible for inclusion. Two series of systematic reviews were performed: (1) accuracy of tests for the prediction of spontaneous preterm birth in asymptomatic women in early pregnancy and in women symptomatic with threatened preterm labour in later pregnancy; (2) effectiveness of interventions with potential to reduce cases of spontaneous preterm birth in asymptomatic women in early pregnancy and to reduce spontaneous preterm birth or improve neonatal outcome in women with a viable pregnancy symptomatic of threatened preterm labour. For the health economic evaluation, a model-based analysis incorporated the combined effect of tests and treatments and their cost-effectiveness. Of the 22 tests reviewed for accuracy, the quality of studies and accuracy of tests was generally poor. Only a few tests had LR+ > 5. In asymptomatic women these were ultrasonographic cervical length measurement and cervicovaginal prolactin and fetal fibronectin screening for predicting spontaneous preterm birth before 34 weeks. In this group, tests with LR- < 0.2 were detection of uterine contraction by home uterine monitoring and amniotic fluid C-reactive protein (CRP) measurement. In symptomatic women with threatened preterm labour, tests with LR+ > 5 were absence of fetal breathing movements, cervical length and funnelling, amniotic fluid interleukin-6 (IL-6), serum CRP for predicting birth within 2-7 days of testing, and matrix metalloprotease-9, amniotic fluid IL-6, cervicovaginal fetal fibronectin and cervicovaginal human chorionic gonadotrophin (hCG) for predicting birth before 34 or 37 weeks. In this group, tests with LR- < 0.2 included measurement of cervicovaginal IL-8, cervicovaginal hCG, cervical length measurement, absence of fetal breathing movement, amniotic fluid IL-6 and serum CRP, for predicting birth within 2-7 days of testing, and cervicovaginal fetal fibronectin and amniotic fluid IL-6 for predicting birth before 34 or 37 weeks. The overall quality of the trials included in the 40 interventional topics reviewed for effectiveness was also poor. Antibiotic treatment was generally not beneficial but when used to treat bacterial vaginosis in women with intermediate flora it significantly reduced the incidence of spontaneous preterm birth. Smoking cessation programmes, progesterone, periodontal therapy and fish oil appeared promising as preventative interventions in asymptomatic women. Non-steroidal anti-inflammatory agents were the most effective tocolytic agent for reducing spontaneous preterm birth and prolonging pregnancy in symptomatic women. Antenatal corticosteroids had a beneficial effect on the incidence of respiratory distress syndrome and the risk of intraventricular haemorrhage (28-34 weeks), but the effects of repeat courses were unclear. For asymptomatic women, costs ranged from 1.08 pounds for vitamin C to 1219 pounds for cervical cerclage, whereas costs for symptomatic women were more significant and varied little, ranging from 1645 pounds for nitric oxide donors to 2555 pounds for terbutaline; this was because the cost of hospitalisation was included. The best estimate of additional average cost associated with a case of spontaneous preterm birth was approximately 15,688 pounds for up to 34 weeks and 12,104 pounds for up to 37 weeks. Among symptomatic women there was insufficient evidence to draw firm conclusions for preventing birth at 34 weeks. Hydration given to women testing positive for amniotic fluid IL-6 was the most cost-effective test-treatment combination. Indomethacin given to all women without any initial testing was the most cost-effective option for preventing birth before 37 weeks among symptomatic women. For a symptomatic woman, the most cost-effective test-treatment combination for postponing delivery by at least 48 h was the cervical length (15 mm) measurement test with treatment with indomethacin for all those testing positive. This combination was also the most cost-effective option for postponing delivery by at least 7 days. Antibiotic treatment for asymptomatic bacteriuria of all women without any initial testing was the most cost-effective option for preventing birth before 37 weeks among asymptomatic women but this does not take into account the potential side effects of antibiotics or issues such as increased resistance. For primary prevention, an effective, affordable and safe intervention applied to all mothers without preceding testing is likely to be the most cost-effective approach in asymptomatic women in early pregnancy. For secondary prevention among women at risk of preterm labour in later pregnancy, a management strategy based on the results of testing is likely to be more cost-effective. Implementation of a treat-all strategy with simple interventions, such as fish oils, would be premature for asymptomatic women. Universal provision of high-quality ultrasound machines in labour wards is more strongly indicated for predicting spontaneous preterm birth among symptomatic women than direct management, although staffing issues and the feasibility and acceptability to mothers and health providers of such strategies need to be explored. Further research should include investigations of low-cost and effective tests and treatments to reduce and delay spontaneous preterm birth and reduce the risk of perinatal mortality arising from preterm birth.

Role of the pediatric nurse practitioner in promoting breastfeeding for late preterm infants in primary care settings.

PubMed

Ahmed, Azza H

2010-01-01

The preterm birth rate has been increasing steadily during the past two decades. Up to two thirds of this increase has been attributed to the increasing rate of late preterm births (34 to < 37 gestational weeks). The advantages of breastfeeding for premature infants appear to be even greater than for term infants; however, establishing breastfeeding in late-preterm infants is frequently more problematic. Because of their immaturity, late preterm infants may have less stamina; difficulty with latch, suck, and swallow; temperature instability; increased vulnerability to infection; hyperbilirubinemia, and more respiratory problems than the full-term infant. Late preterm infants usually are treated as full term and discharged within 48 hours of birth, so pediatric nurse practitioners in primary care settings play a critical role in promoting breastfeeding through early assessment and detection of breastfeeding difficulties and by providing anticipatory guidance related to breastfeeding and follow-up. The purpose of this article is to describe the developmental and physiologic immaturity of late preterm infants and to highlight the role of pediatric nurse practitioners in primary care settings in supporting and promoting breastfeeding for late preterm infants.

Preterm birth

PubMed Central

2010-01-01

Introduction Preterm birth occurs in about 5% to 10% of all births in resource-rich countries, but in recent years the incidence seems to have increased in some countries, particularly in the USA. We found little reliable evidence for incidence in resource-poor countries. The rate in northwestern Ethiopia has been reported to vary from 11% to 22%, depending on the age group of mothers studied, and is highest in teenage mothers. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of preventive interventions in women at high risk of preterm delivery? What are the effects of interventions to improve neonatal outcome after preterm rupture of membranes? What are the effects of treatments to stop contractions in preterm labour? What are the effects of elective compared with selective caesarean delivery for women in preterm labour? What are the effects of interventions to improve neonatal outcome in preterm delivery? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 58 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: amnioinfusion for preterm rupture of membranes; antenatal corticosteroids; antibiotic treatment; bed rest; beta mimetics; calcium-channel blockers; elective caesarean; enhanced antenatal care programmes; magnesium sulphate; oxytocin receptor antagonists (atosiban); progesterone; prophylactic cervical cerclage; prostaglandin inhibitors (e.g., indometacin); selective caesarean; and thyrotropin-releasing hormone (TRH) (plus corticosteroids).

Preterm birth

PubMed Central

2011-01-01

Introduction Preterm birth occurs in about 5% to 10% of all births in resource-rich countries, but in recent years the incidence seems to have increased in some countries, particularly in the USA. We found little reliable evidence for incidence in resource-poor countries. The rate in northwestern Ethiopia has been reported to vary from 11% to 22%, depending on the age group of mothers studied, and is highest in teenage mothers. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of preventive interventions in women at high risk of preterm delivery? What are the effects of interventions to improve neonatal outcome after preterm rupture of membranes? What are the effects of treatments to stop contractions in preterm labour? What are the effects of elective compared with selective caesarean delivery for women in preterm labour? What are the effects of interventions to improve neonatal outcome in preterm delivery? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 58 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: amnioinfusion for preterm rupture of membranes, antenatal corticosteroids, antibiotic treatment, bed rest, beta-mimetics, calcium channel blockers, elective caesarean, enhanced antenatal care programmes, magnesium sulphate, oxytocin receptor antagonists (atosiban), progesterone, prophylactic cervical cerclage, prostaglandin inhibitors (e.g., indometacin), selective caesarean, and thyrotropin-releasing hormone (TRH) (plus corticosteroids). PMID:21463540

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

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.

[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.