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Background and aim: Paternal use of analgesics during the time of conception and adverse birth outcomes are poorly studied. We investigated the association between paternal exposure to non‐steroid anti‐inflammatory drugs and opioids within 3 months before the date of conception and the risk of adverse birth outcomes (preterm birth, small for gestational age, low Apgar score, and major congenital malformations). Methods: We used nationwide data from the Danish health registers. We included information on all singleton live births, and their fathers and mothers from 1997 to 2018. We created two exposed cohorts, children with preconception paternal exposure to (1) non‐steroid anti‐inflammatory drugs and (2) opioids. The unexposed cohort was children without preconception paternal exposure to non‐steroid anti‐inflammatory drugs or opioids, and we performed a sub‐analysis against paternal use of acetaminophen (paracetamol). We used logistic regression models to estimate the odds ratios of adverse birth outcomes including 95% confidence intervals. Results: We identified 1,260,934 children, 45,667 children with paternal exposure to non‐steroid anti‐inflammatory drugs, 10,086 children with paternal exposure to opioids, and 1,205,181 unexposed children. The adjusted odds ratio for preterm birth was 1.08 (95% confidence interval, 1.03–1.13) after paternal exposure to non‐steroid anti‐inflammatory drugs and 1.21 (95% confidence interval, 1.08–1.35) after paternal exposure to opioids. The adjusted odds ratio for small for gestational age was 1.09 (95% confidence interval, 1.03–1.17) after paternal exposure to non‐steroid anti‐inflammatory drugs, and 1.03 (95% confidence interval, 0.88–1.21) after paternal exposure to opioids. We found null‐associations for a low Apgar score and major congenital malformations. Estimates were attenuated when compared against paternal paracetamol exposure. Conclusions: Overall, we found null‐associations across the comparisons made. Weak associations were found for paternal exposure to non‐steroid anti‐inflammatory drugs or opioids and preterm birth and small for gestational age, but not with low Apgar score or major congenital malformation. All associations were attenuated when compared against an active comparator of paternal paracetamol exposure. The effect sizes were small and less likely to be of clinical relevance. [ABSTRACT FROM AUTHOR]

Background and aims: Stimulant‐related disorders (SRD), or the continued misuse of illicit or prescribed stimulants, during pregnancy can have adverse health effects for mothers and infants. This study aimed to measure prevalence and trends of SRD diagnosis in pregnancy, and associations between SRD diagnosis and adverse maternal and infant health outcomes, among pregnant individuals in California. Design: Retrospective cohort study. Setting: California, USA. Participants: Pregnant individuals from the Study of Outcomes in Mothers and Infants (SOMI) with singleton live births between 2012 and 2020 (n = 3 740 079). Measurements: SRD diagnosis (excluding cocaine) and maternal (gestational diabetes, gestational hypertension [gHTN], severe maternal morbidity [SMM]) and infant (very preterm birth [gestational age <32 weeks], preterm birth [gestational age 32–37 weeks], neonatal intensive care unit [NICU] admission, small for gestational age [SGA]) outcomes were classified using International Classification of Disease (ICD) codes and vital statistics. Risk ratios were estimated with modified Poisson log linear regression that accounted for sibling pregnancies. Covariates included maternal sociodemographic characteristics, mental and physical health problems, nicotine use and co‐occurrence of other diagnosed substance use disorders. Bias analyses were conducted to address unmeasured confounding and exposure misclassification. Findings SRD diagnosis among pregnant individuals increased from 2012 to 2020 (554 to 748 per 100 000 births). SRD diagnosis was associated with an increased risk of SMM (adjusted risk ratio [aRR] = 2.3; 95% confidence interval [CI] = 2.2–2.5), gHTN (aRR = 1.8; 95% CI = 1.7–1.9), very preterm birth (aRR = 2.2, 95% CI = 2.0–2.5), preterm birth (aRR = 2.1, 95% CI = 2.1–2.2) and NICU admission (aRR = 2.0, 95%CI = 1.9–2.0), and a decreased risk of gestational diabetes (aRR = 0.8; 95% CI = 0.8–0.9). SRD diagnosis was not associated with infants born SGA. Findings were generally robust to unmeasured confounding and misclassification of diagnosis. Conclusions: Stimulant‐related disorder diagnosis during pregnancy appears to be associated with an increased risk for select adverse maternal and infant health outcomes including severe maternal morbidity, gestational hypertension, very preterm birth, preterm birth and neonatal intensive care unit admission. [ABSTRACT FROM AUTHOR]

Background: Nausea and vomiting of pregnancy (NVP) occurs in approximately 70% of pregnant people, with varying severity and duration. Treatments include pharmacologic and herbal/natural medications. The associations between NVP and birth outcomes, including preterm birth, small for gestational age (SGA), and low birth weight are inconclusive. Objective: To determine whether NVP and reported medications are associated with adverse birth outcomes. Methods: We used data from the population‐based, multisite National Birth Defects Prevention Study (1997–2011) to evaluate whether self‐reported NVP according to timing, duration, and severity or its specific treatments were associated with preterm birth, SGA, and low birth weight among controls without birth defects. Odds ratios (aOR) and 95% confidence intervals (CI) were adjusted for sociodemographic, reproductive, and medical factors. For any NVP, duration, treatment use, and severity score analyses, the comparison group was participants with no reported NVP. For timing analyses, the comparison group was women with no reported NVP in the same trimester of pregnancy. Results: Among 6018 participants, 4339 (72.1%) reported any NVP. Among those with NVP, moderate or severe symptoms were more common than mild symptoms. Any versus no NVP was not associated with any of the outcomes of interest. NVP in months 4–6 (aOR 1.21, 95% CI: 1.00, 1.47) and 7–9 (aOR 1.57, 95% CI: 1.22, 2.01) of pregnancy were associated with an increase in the risk of preterm birth. NVP lasting one trimester in duration was associated with decrease in risk of SGA (aOR: 0.74, 95% CI: 0.58, 0.95), and NVP present in every trimester of pregnancy had a 50% increase in risk of preterm birth (aOR: 1.50, 95% CI: 1.11, 2.05). For NVP in months 7–9 and preterm birth, ORs were elevated for moderate (aOR: 1.82, 95% CI: 1.26, 2.63), and severe (aOR: 1.53, 95% CI: 1.06, 2.19) symptoms. NVP was not significantly associated with low birth weight. Our analyses of medications were limited by small numbers, but none suggested increased risk of adverse outcomes associated with use of the medication. Conclusion: Mild NVP and NVP limited to early pregnancy appear to have no effect or a small protective effect on birth outcomes. Long‐lasting NVP, severe NVP, and NVP later in pregnancy may increase risk of preterm birth and SGA. [ABSTRACT FROM AUTHOR]

Epidemiological data provide varying degrees of evidence for associations between prenatal exposure to ambient air pollutants and adverse birth outcomes (suboptimal measures of fetal growth, preterm birth and stillbirth). To assess further certainty of effects, this review examines the experimental literature base to identify mechanisms by which air pollution (particulate matter, nitrogen dioxide and ozone) could cause adverse effects on the developing fetus. It likely that this environmental insult impacts multiple biological pathways important for sustaining a healthy pregnancy, depending upon the composition of the pollutant mixture and the exposure window owing to changes in physiologic maturity of the placenta, its circulations and the fetus as pregnancy ensues. The current body of evidence indicates that the placenta is a target tissue, impacted by a variety of critical processes including nitrosative/oxidative stress, inflammation, endocrine disruption, epigenetic changes, as well as vascular dysregulation of the maternal‐fetal unit. All of the above can disturb placental function and, as a consequence, could contribute to compromised fetal growth as well increasing the risk of stillbirth. Furthermore, given that there is often an increased inflammatory response associated with preterm labour, inflammation is a plausible mechanism mediating the effects of air pollution on premature delivery. In the light of increased urbanisation and an ever‐changing climate, both of which increase ambient air pollution and negatively affect vulnerable populations such as pregnant individuals, it is hoped that the collective evidence may contribute to decisions taken to strengthen air quality policies, reductions in exposure to air pollution and subsequent improvements in the health of those not yet born. [ABSTRACT FROM AUTHOR]

Aims: The role of maternal genetic factors in the association between high glycated haemoglobin (HbA1c) levels and adverse birth outcomes remains unclear. Materials and Methods: In this study, the maternal HbA1c levels of 5108 normoglycemic pregnant women in China were measured, and A1298C and C677T polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene were genotyped. Results: Elevated HbA1c levels during the second trimester were associated with increased risks of macrosomia, large‐for‐gestational age (LGA), preterm birth (PTB), and reduced gestational age (p < 0.05). Pregnant women with MTHFR A1298C AA or C677T CT + TT genotypes were susceptible to adverse pregnancy outcomes related to HbA1c levels. Among pregnant women with the A1298C AA genotype, each standard deviation (SD) increase in HbA1c levels increased the risk of PTB by 1.32‐times and reduced the gestational age by 0.11 weeks (p < 0.05). For MTHFR C677T CC + TT genotype carriers, higher HbA1c levels were associated with 1.49‐, 1.24‐, and 1.23‐times increased risks of macrosomia, LGA, and PTB, respectively (p < 0.05). A U‐shaped curve for PTB risk in relation to HbA1c levels was observed among the C677T CC + TT participants, with a cut‐off value of 4.58%. Among subjects with the A1298C AA genotype combined with the C677T CT + TT genotype, each SD increase in HbA1c levels was associated with 1.40 and 1.37‐times increased risks of LGA and PTB, respectively. Conclusions: Our findings highlight the importance of glycaemic control during pregnancy and the potential impact of genetic factors on birth outcomes. However, further large‐scale studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]

Data on the safety of inactivated COVID‐19 vaccines in pregnant women is limited and monitoring pregnancy outcomes is required. We aimed to examine whether vaccination with inactivated COVID‐19 vaccines before conception was associated with pregnancy complications or adverse birth outcomes. We conducted a birth cohort study in Shanghai, China. A total of 7000 healthy pregnant women were enrolled, of whom 5848 were followed up through delivery. Vaccine administration information was obtained from electronic vaccination records. Relative risks (RRs) of gestational diabetes mellitus (GDM), hypertensive disorders in pregnancy (HDP), intrahepatic cholestasis of pregnancy (ICP), preterm birth (PTB), low birth weight (LBW), and macrosomia associated with COVID‐19 vaccination were estimated by multivariable‐adjusted log‐binomial analysis. After exclusion, 5457 participants were included in the final analysis, of whom 2668 (48.9%) received at least two doses of an inactivated vaccine before conception. Compared with unvaccinated women, there was no significant increase in the risks of GDM (RR = 0.80, 95% confidence interval [CI], 0.69, 0.93), HDP (RR = 0.88, 95% CI, 0.70, 1.11), or ICP (RR = 1.61, 95% CI, 0.95, 2.72) in vaccinated women. Similarly, vaccination was not significantly associated with any increased risks of PTB (RR = 0.84, 95% CI, 0.67, 1.04), LBW (RR = 0.85, 95% CI, 0.66, 1.11), or macrosomia (RR = 1.10, 95% CI, 0.86, 1.42). The observed associations remained in all sensitivity analyses. Our findings suggested that vaccination with inactivated COVID‐19 vaccines was not significantly associated with an increased risk of pregnancy complications or adverse birth outcomes. [ABSTRACT FROM AUTHOR]

Nitrous oxide is commonly used in Australia for labour analgesia. Its use in labour is potentially associated with aerosol generation. During the first wave of the COVID‐19 pandemic of 2020, nitrous oxide was suspended on many birthing units to reduce the risk of transmission. We aimed to determine the impact of withholding nitrous oxide for labour analgesia, during the COVID‐19 pandemic, on epidural rates, opioid analgesia use, and maternal and neonatal outcomes. Withholding nitrous oxide for labour analgesia did not alter epidural rates but did significantly increase opioid analgesia use. Caesarean section rates, post‐partum blood loss and neonatal APGAR scores did not change. [ABSTRACT FROM AUTHOR]

Problem: Several biomarkers have been studied to predict spontaneous preterm birth, including salivary progesterone. However, due to limited studies, the utility of this biomarker remains controversial. This study synthesized the available literature and determined the role of salivary progesterone as a potential biomarker for preterm birth. Method of Study: All studies reporting the levels of salivary progesterone among pregnant women with reported birth outcomes were obtained from Ovid Medline, Scopus, CINAHL, and Cochrane Central Register of Controlled Trials from inception to January 10, 2022. A review of titles and abstracts was done independently by three reviewers. The quality of the studies was assessed using the Newcastle‐Ottawa scale. Meta‐analysis was performed in R v.4.1.3 using the "meta" package. Results: Five studies involving 861 pregnant patients from Egypt, India, Iraq, and the US were included in this meta‐analysis. The random‐effects model showed that salivary progesterone level after the 28th week of gestation was significantly different between patients with term and preterm birth (standardized mean difference [SMD]: 1.99; 95% confidence interval [CI]:.44–3.54) with a high degree of heterogeneity (I2 = 96%, P <.001). Based on the results of this meta‐analysis, women with term birth had higher level of salivary progesterone after the 28th week of gestation than those with preterm birth. Conclusion: In conclusion, the study results suggest that low salivary progesterone level after the 28th week of gestation is significantly associated with preterm birth. This study also highlights the use of saliva samples for monitoring sex steroid hormones throughout pregnancy. [ABSTRACT FROM AUTHOR]

Background: Antiretroviral therapy (ART) use during pregnancy may be associated with adverse outcomes, but findings have been inconsistent, at least in part due to unreliably estimated gestational age.Objective: To quantify the association between HIV status, ART initiation timing and adverse birth outcomes, with reliably assessed gestational age at booking, in a public sector primary care facility in Cape Town, South Africa.Methods: Pregnant women, HIV-negative or living with HIV (WLHIV), were enrolled at first antenatal care visit and followed through delivery. Ultrasound-assessed gestational age was deemed the gold standard. Based on quantitative bias analysis for outcome misclassification, gestational age by non-ultrasound assessment was corrected using multiple overimputation, which deals with missing data and measurement error simultaneously. Using bias-corrected gestational age, birth outcomes were compared between WLHIV and HIV-negative women, and among WLHIV who initiated ART before versus during pregnancy, further divided into trimesters.Results: Of 3952 women enrolled, 37% were WLHIV (mostly using tenofovir + emtricitabine + efavirenz). Last menstrual period (LMP)-based gestational age was identified to be biased, and LMP measures were thus corrected using multiple overimputation. Comparing WLHIV and HIV-negative women, adjusted risk ratio (aRR) of overall pregnancy loss was 1.26 (95% confidence interval [CI] 0.98, 1.61); aRR of preterm delivery was 1.02 (95% CI 0.88, 1.20); aRR of small for gestational age infants was 1.43 (95% CI 1.14, 1.80). Among WLHIV, outcomes were similar by ART initiation timing.Conclusions: In this routine care cohort, risk of SGA, and possibly of pregnancy loss, was increased in WLHIV compared with HIV-negative women, with no evidence of increased risk of preterm delivery. Further research is needed to improve mechanistic understanding of the contribution of ART to adverse birth outcomes to optimize treatment for pregnant WLHIV and ensure optimal maternal and infant outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Although non‐Hispanic Black women have increased risks of adverse birth outcomes compared with non‐Hispanic white women in the United States, there is a lack of research specifically focusing on non‐Hispanic Black women. Thus, this study's purpose was to evaluate whether place of birth and type of attendant used during labor is associated with having a newborn born small for gestational age (SGA) among non‐Hispanic Black Medicaid recipients. Methods: This study used 2017 Natality data from the National Vital Statistics System for non‐Hispanic Black women who used Medicaid as a source of payment (N = 322,604). Type of attendant (ie, the medical professional who assisted during childbirth), place of birth (ie, setting where the woman gave birth), maternal factors, and SGA were obtained from birth certificates. We used multivariate logistic regression to investigate the association between place of birth, type of birth attendant, and newborns born SGA. Results: After adjustment, women who used a certified nurse‐midwife or other midwife as an attendant during labor had statistically significant decreased odds of having a neonate born SGA compared with those who had a physician as an attendant (odds ratio [OR], 0.69; 95% CI, 0.66‐0.71 and OR, 0.68; 95% CI, 0.55‐0.85, respectively). Those who gave birth in a birthing center or had planned home births also had statistically significant decreased odds of having a neonate born SGA (OR, 0.52; 95% CI, 0.38‐0.69 and OR, 0.37; 95% CI, 0.21‐0.66, respectively). However, those who had an unplanned home birth had twice the odds of having a neonate born SGA compared with those who gave birth at a hospital or clinic (OR, 2.00; 95% CI, 1.50‐2.64). Discussion: Given the racial disparity in adverse birth outcomes for non‐Hispanic Black women, the observed associations provide justification for future research to determine whether birthing location and birth attendant are related to SGA. [ABSTRACT FROM AUTHOR]

The association between in utero exposure to indoor PM2.5 and birth outcomes is not conclusive. We assessed the association between in utero exposure to indoor PM2.5, birth weight, gestational age, low birth weight, and/or preterm delivery. Homes of 800 pregnant women were assessed using a structured walkthrough questionnaire. PM2.5 measurements were undertaken in 300 of the 800 homes for a period of 24 h. Repeated sampling was conducted in 30 of these homes to determine PM2.5 predictors that can reduce within‐and/or between‐home variability. A predictive model was used to estimate PM2.5 levels in unmeasured homes (n = 500). The mean (SD) for PM2.5 was 37 µg/m3 (29) with a median of 28µg/m3. The relationship between PM2.5 exposure, birth weight, gestational age, low birth weight, and preterm delivery was assessed using multivariate linear and logistic regression models. We explored infant sex as a potential effect modifier, by creating an interaction term between PM2.5 and infant sex. The odds ratio of low birth weight and preterm delivery was 1.75 (95%CI: 1.47, 2.09) and 1.21 (95%CI: 1.06, 1.39), respectively, per interquartile increase (18 µg/m3) in PM2.5 exposure. The reduction in birth weight and gestational age was 75 g (95%CI: 107.89, 53.15) and 0.29 weeks (95%CI: 0.40, 0.19) per interquartile increase in PM2.5 exposure. Infant sex was an effect modifier for PM2.5 on birth weight and gestational age, and the reduction in birth weight and gestational age was 103 g (95%CI: 142.98, 64.40) and 0.38 weeks (95% CI: 0.53, 0.23), respectively, for boys, and 54 g (95%CI: 91.78,15.62) and 0.23 weeks (95%CI:0.37, 0.08), respectively, for girls. Exposure to PM2.5 is associated with adverse pregnancy outcomes. To protect the population during their reproductive period, public health policy should focus on indoor PM2.5 levels. [ABSTRACT FROM AUTHOR]

Purpose: Distances to obstetric care providers are a persistent concern, especially for rural pregnant adolescents. Births to adolescents are disproportionately affected by adverse birth outcomes (ABOs), yet little is known regarding how driving distances may impact ABOs. This study examines the association between driving distances to obstetric providers and ABOs among adolescent mothers in South Carolina. Methods: This retrospective cross‐sectional study derived ZIP Code‐level birth statistics from mothers aged 10–19 in South Carolina using 2013–2017 statewide birth certificate data. ABOs included preterm birth and/or low birthweight. Provider distance was calculated between an obstetric provider's ZIP Code tabulated area (ZCTA) centroid and a maternal resident's ZCTA centroid. Descriptive statistics and weighted generalized linear regression were conducted. Results: Mean provider distances to obstetric providers were similar between urban (11.76 miles) and rural adolescent mothers (12.04 miles). An increase in provider distance, on average, was associated with a decrease in ABO rates (–0.79, p=.0038); however, rural–urban differences were found. Living in a rural ZCTA was associated with a decrease in ABOs (4.94%, p =.0043). Urban ZCTAs showed a U‐shaped association with provider distance, with ABO rates decreasing until approximately 17 miles away from a provider and then increasing. Conclusion: Rural adolescent mothers with greater distance to providers had lower ABO rates, while, in urban ZCTAs, provider distance over 17 miles was associated with higher ABO rates. Understanding what mitigates the effects of driving distance on ABOs in rural South Carolina would help inform future policy planning in underserved communities. [ABSTRACT FROM AUTHOR]

Background: Trichomoniasis commonly affects women of childbearing age and has been linked to several adverse birth outcomes. Objective: To elucidate the association between trichomoniasis in pregnant women and adverse birth outcomes, including preterm delivery, prelabour rupture of membranes and low birthweight. Search strategy: MEDLINE, EMBASE and ClinicalTrials.gov were systematically searched in December 2020 without time or language restrictions. Selection criteria: Original research studies were included if they assessed at least one of the specified adverse birth outcomes in pregnant women with laboratory‐diagnosed trichomoniasis. Data collection and analysis: Estimates from included articles were either extracted or calculated and then pooled to produce a combined estimate of the association of trichomoniasis with each adverse birth outcome using the random effects model. Heterogeneity was assessed using the I2 statistic and Cochran's Q test. Main results: Literature search produced 1658 publications after removal of duplicates (n = 770), with five additional publications identified by hand search. After screening titles and abstracts for relevance, full text of 84 studies was reviewed and 19 met inclusion criteria for meta‐analysis. Significant associations were found between trichomoniasis and preterm delivery (OR 1.27; 95% CI 1.08–1.50), prelabour rupture of membranes (OR 1.87; 95% CI 1.53–2.29) and low birthweight (OR 2.12; 95% CI 1.15–3.91). Conclusions: Trichomoniasis in pregnant women is associated with preterm delivery, prelabour rupture of membranes and low birthweight. Rigorous studies are needed to determine the impact of universal trichomoniasis screening and treatment during pregnancy on reducing perinatal morbidity. This systematic review and meta‐analysis found that in the setting of pregnancy, trichomoniasis is significantly associated with multiple adverse birth outcomes, including preterm delivery, low birthweight, and prelabour rupture of membranes. This systematic review and meta‐analysis found that in the setting of pregnancy, trichomoniasis is significantly associated with multiple adverse birth outcomes, including preterm delivery, low birthweight, and prelabour rupture of membranes. [ABSTRACT FROM AUTHOR]

Women are particularly susceptible to developing gingival problems during pregnancy. In addition, periodontal disease in pregnant women may lead to adverse outcomes for both mother and infant, which have serious clinical and public health implications. Both scenarios have been extensively researched, helping to bring attention to pregnant women as an important and vulnerable population as it concerns periodontal health. The increase in gingival inflammation caused by hormonal changes in pregnant women is undisputed and has been studied and documented since the 1960s, although the exact etiology is not fully understood. The relationship between periodontal disease during pregnancy and adverse pregnancy outcomes is less substantiated, because of conflicting evidence. This review of the biomedical and epidemiologic literature provides an overview of both sides of this relationship and examines the potential mechanisms for developing periodontal disease during pregnancy and the proposed mechanisms by which periodontal disease leads to adverse pregnancy outcomes. [ABSTRACT FROM AUTHOR]

Keywords: Adverse birth outcomes; Black women; obstetric racism; patient reported experience measure; Quality Improvement EN Adverse birth outcomes Black women obstetric racism patient reported experience measure Quality Improvement 681 684 4 10/06/21 20210901 NES 210901 For years, one of the most well-known responses to the question of why Black women's birth outcomes were adverse was race. Developed by Dr. Karen A. Scott, an OB/GYN hospitalist and applied epidemiologist in sexual, reproductive, and perinatal health, the PREM-OB Scale™ translates obstetric racism into examples of harmful clinical practice techniques that violate patient safety, autonomy, dignity, and humanity during hospitalization for labor, birth, and immediate postpartum (Scott 2019). Adverse birth outcomes, Black women, obstetric racism, patient reported experience measure, Quality Improvement Health Equity 4 (1): 17 - 22. 24 Scott, Karen A., and Tanefer Camara. [Extracted from the article]

Bivariate copula regression allows for the flexible combination of two arbitrary, continuous marginal distributions with regression effects being placed on potentially all parameters of the resulting bivariate joint response distribution. Motivated by the risk factors for adverse birth outcomes, many of which are dichotomous, we consider mixed binary-continuous responses that extend the bivariate continuous framework to the situation where one response variable is discrete (more precisely, binary) whereas the other response remains continuous. Utilizing the latent continuous representation of binary regression models, we implement a penalized likelihood-based approach for the resulting class of copula regression models and employ it in the context of modeling gestational age and the presence/absence of low birth weight. The analysis demonstrates the advantage of the flexible specification of regression impacts including nonlinear effects of continuous covariates and spatial effects. Our results imply that racial and spatial inequalities in the risk factors for infant mortality are even greater than previously suggested. [ABSTRACT FROM AUTHOR]

Background: Particulate matter (PM) has been documented to contribute to preterm delivery. However, few studies have investigated the relationships between individual constituents of fine PM (PM2.5 ) and preterm delivery, and factors that may modify their associations.Methods: In this study, we examined the associations between several prenatal exposure metrics to PM2.5 and 23 constituents of PM2.5 and preterm delivery in California from 2000 to 2006. In a retrospective cohort study including 231 637 births, we conducted logistic regression analyses adjusting for maternal, infant, temporal, geographic, and neighbourhood characteristics.Results: We observed increased risk for preterm delivery with full-gestational exposure for several PM2.5 constituents. Per interquartile range increase, ammonium (21.2%, 95% confidence interval (CI) 17.1, 25.4), nitrate (18.1%, 95% CI 14.9, 21.4) and bromine (16.7%, 95% CI 13.2, 20.3) had some of the largest increased risks. Alternatively, some PM2.5 constituents were inversely associated with preterm delivery, including chlorine (-8.2%, 95% CI -10.3, -6.0), sodium (-13.2%, 95% CI -15.2, -11.3), sodium ion (-11.9%, 95% CI -14.1, -9.6) and vanadium (-19.2%, 95% CI -25.3, -12.6). Greater associations between PM2.5 constituents and preterm delivery were observed for Blacks and Asians, older mothers, and those with some college education compared to their reference groups, as well as for births with gestational ages from 32 to 34 weeks.Conclusions: PM2.5 constituents ammonium, nitrate and bromine, often linked to traffic and biomass combustion, were most associated with increased risk of preterm delivery in California. Certain demographic subgroups may be particularly impacted. [ABSTRACT FROM AUTHOR]

Background: The 3D Cohort Study (Design, Develop, Discover) was established to help bridge knowledge gaps about the links between various adverse exposures during pregnancy with birth outcomes and later health outcomes in children.Methods: Pregnant women and their partners were recruited during the first trimester from nine sites in Quebec and followed along with their children through to 2 years of age. Questionnaires were administered during pregnancy and post-delivery to collect information on demographics, mental health and life style, medical history, psychosocial measures, diet, infant growth, and neurodevelopment. Information on the delivery and newborn outcomes were abstracted from medical charts. Biological specimens were collected from mothers during each trimester, fathers (once during the pregnancy), and infants (at delivery and 2 years of age) for storage in a biological specimen bank.Results: Of the 9864 women screened, 6348 met the eligibility criteria and 2366 women participated in the study (37% of eligible women). Among women in the 3D cohort, 1721 of their partners (1704 biological fathers) agreed to participate (73%). Two thousand two hundred and nineteen participants had a live singleton birth (94%). Prenatal blood and urine samples as well as vaginal secretions were collected for ≥98% of participants, cord blood for 81% of livebirths, and placental tissue for 89% of livebirths.Conclusions: The 3D Cohort Study combines a rich bank of multiple biological specimens with extensive clinical, life style, and psychosocial data. This data set is a valuable resource for studying the developmental etiology of birth and early childhood neurodevelopmental outcomes. [ABSTRACT FROM AUTHOR]

Background Although adverse birth outcomes have been associated with neighbourhood deprivation in urban areas, few studies have addressed this issue in rural zones. This study examines whether associations between neighbourhood deprivation and adverse birth outcomes differ in urban and rural contexts, while taking individual characteristics and spatial accessibility of prenatal care ( SAPC) into account. Methods Pregnant women from a French mother-child cohort were recruited from 2002 to 2006 in Brittany. Their residential addresses were geocoded into their census blocks (the finest geographical resolution available). Deprivation was assessed at the same neighbourhood level. Models to assess the associations of deprivation, stratified by urban/rural status, with preterm delivery ( PTD), with small for gestational age birth weight ( SGA) and with small for gestational age head circumference at birth ( SHC), estimated odds ratios ( ORs), adjusted for maternal socioeconomic characteristics and SAPC. Results This study considered 2929 liveborn singleton pregnancies from 780 census blocks. Neighbourhood deprivation was associated with increased risks of SGA and SHC ( P trend < 0.01 and 0.03 respectively), only among mothers residing in rural areas. Neighbourhood deprivation had statistically significantly heterogeneous effects on SGA and SHC according to the urban/rural status of maternal residence. Conclusion These findings suggest that neighbourhood deprivation affects fetal growth differentially in urban and rural areas and that SAPC does not seem to be responsible for this difference. Comparison of these findings with the literature requires caution in the conceptualisation of urban and rural settings. [ABSTRACT FROM AUTHOR]

Background To determine sociodemographic and life style-related risk factors and trimester specific maternal, placental, and fetal consequences of maternal anaemia and elevated haemoglobin levels in pregnancy. Methods In a population-based prospective cohort study of 7317 mothers, we measured haemoglobin levels in early pregnancy [gestational age median 14.4 weeks (inter-quartile-range 12.5-17.5)]. Anaemia (haemoglobin ≤11 g/dl) and elevated haemoglobin levels (haemoglobin ≥13.2 g/dl) were defined according to the WHO criteria. Maternal blood pressure, placental function and fetal growth were measured in each trimester. Data on gestational hypertensive disorders and birth outcomes was collected from hospitals. Results Older maternal age, higher body mass index, primiparity and European descent were associated with higher haemoglobin levels ( P < 0.05). Elevated haemoglobin levels were associated with increased systolic and diastolic blood pressure throughout pregnancy (mean differences 5.1 mmHg, 95% confidence interval [ CI] 3.8, 6.5 and 4.1 mmHg, 95% CI 3.0, 5.2, respectively) and with a higher risk of third trimester uterine artery notching ( RR 1.3, 95% CI 1.0, 1.7). As compared with maternal normal haemoglobin levels, not anaemia, but elevated haemoglobin levels were associated with fetal head circumference, length, and weight growth restriction from third trimester onwards ( P < 0.05). Elevated haemoglobin levels were associated with increased risks of gestational hypertensive disorders ( RR 1.4, 95% CI 1.1, 1.8) and adverse birth outcomes ( RR 1.4, 95% CI 1.1, 1.7). Conclusions In a low-risk population, various sociodemographic and life style factors affect haemoglobin levels during pregnancy. Elevated haemoglobin levels are associated with increased risks of maternal, placental, and fetal complications. [ABSTRACT FROM AUTHOR]

This study assesses the overall spatial variations and neighbourhood-level 'hot spots' of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra-class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2-3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual-level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community-oriented health interventions may be required to reduce observed local health impacts. [ABSTRACT FROM AUTHOR]