Pregnancy Outcomes And Community Health Research Articles

Diet Quality, Sedentary Time, and Blood Pressure in the POUCHmoms Study

BackgroundElevated blood pressure (BP) is a major contributor to cardiovascular disease in womens; diet and sedentary time (ST) are modifiable lifestyle factors thought to influence BP. ObjectivesThe aim of this study was to examine 2 diet-quality measures and ST in relation to BP among parous womens. MethodsThis cross-sectional analysis uses data from 677 womens (age 25–55 y) enrolled in the Pregnancy Outcomes and Community Health (POUCH) Study and followed up in the POUCHmoms study 7–15 y after delivery (2011 and 2014). Follow-up measures included a food-frequency questionnaire (FFQ), self-report of ST (occupational and leisure), and systolic and diastolic blood pressure (SBP and DBP, respectively). The FFQ was used to calculate 2 diet-quality measures, Alternative Healthy Eating Index-2010 (AHEI) and Dietary Approaches to Stop Hypertension (DASH). Total ST h/wk was dichotomized at the median and labeled “low” or “high.” In weighted unadjusted and adjusted regression models, BP was assessed in relation to diet scores (linear and threshold associations) and combinations of dichotomized diet-quality scores (“poor” = lowest quartile compared with “not poor” = upper 3 quartiles) and ST. ResultsHigher mean SBP and DBP occurred mainly in women with a ‘“poor” diet-quality score (AHEI and DASH). Among womens with a “poor”-quality diet (on the basis of the AHEI score) and “high” ST, (N = 93) adjusted mean SBP and DBP were 4.5 mmHg and 4.4 mmHg higher, respectively, than that of the counterparts who did not have a poor-quality diet and had “low” ST (N = 275). Results were similar in analyses using the DASH diet score. ConclusionsWomen with poor-quality diets and more ST may need closer BP monitoring. Even modest improvements in womens’ diet quality and reductions in ST might help lower their BP, but this observation needs testing in prospective studies..

Breastfeeding Greater Than 6 Months Is Associated with Smaller Maternal Waist Circumference Up to One Decade After Delivery.

Abdominal obesity is an important indicator of cardiometabolic dysfunction in later life. Prior studies have observed an inverse association between breastfeeding and maternal waist circumference (WC) in the years after pregnancy, but this may be due to bias resulting from systematic differences in women who do and do not breastfeed. A total of 678 women enrolled in the Pregnancy Outcomes and Community Health (POUCH) cohort also participated in the POUCHmoms Study 7-15 years after delivery. Multivariable linear regression models and propensity scores were used to assess the relationship between WC measured at follow-up and self-reported history of breastfeeding duration of >6 months versus ≤6 months. After a mean follow-up period of 11.0 (standard deviation = 1.4) years, breastfeeding was significantly associated with smaller WC. A threshold effect was detected for women who reported breastfeeding >6 months; their adjusted mean WC was 3.5 cm (95% confidence interval [CI]: -5.7 to -1.2) smaller compared with women who breastfed ≤6 months. The use of two propensity score approaches, weighted and matched, produced similar results; adjusted mean WC difference was -3.6 cm (95% CI: -5.6 to -1.6) and -3.1 cm (95% CI: -5.5 to -0.7), respectively. This study extends conventional observational study methods to incorporate propensity score approaches that make it possible to separate the study design from the study analysis to account for systematic differences in women who did and did not breastfeed. After reducing potential bias, breastfeeding for greater than 6 months was independently associated with smaller WC in the decade after delivery.

Placental pathology, corticotropin-releasing hormone, timing of parturition, and fetal growth in the pregnancy outcomes and community health study

Background: Identification of vascular pathologies in delivered placentas and their associations with biomarkers measured during pregnancy may elucidate mechanisms of adverse pregnancy outcomes and inform early detection and intervention strategies.Objectives: To examine associations of placental vascular pathology with birth size and timing of parturition, and to evaluate maternal midpregnancy serum corticotropin-releasing hormone (CRH) levels as a marker of the above associations.Study design: The pregnancy outcomes and community health (POUCH) Study enrolled women at 16–27 weeks of pregnancy from five Michigan communities. Histological assessments of delivered placentas and assays of CRH in maternal blood sampled at enrollment were performed in a subcohort of 1152 participants. Five placental vascular pathology constructs were formulated: Maternal–Vascular-Obstructive (MVO), Fetal Vascular–Obstructive (FVO), Maternal Vascular–disturbance of Integrity (MVI), Fetal Vascular–disturbance of Integrity (FVI), and Maternal Vascular–Developmental (MVD). A four-level outcome variable combined small for gestational (SGA) yes/no and delivery timing preterm/term; the non-SGA/term served as the referent group. In multinomial logistic regression models, the five vascular pathology groups were evaluated in relation to the outcome variable and effect sizes were compared before versus after exclusion of participants with high CRH (top quartile).Results: Adjusted odds ratios (aOR) for MVO among SGA/term and SGA/preterm were 4.1 (95% CI: 2.2, 7.9) and 8.8 (95% CI: 3.3, 23.5) respectively. Among SGA/preterm births, the aOR was attenuated by ∼40%, i.e. 5.4 (95% CI: 1.1, 26.2) after removing high CRH pregnancies. MVI and FVO were each associated with SGA/preterm, aOR = 3.7 (95% CI: 1.3, 10.3) and 10.5 (95% CI: 3.6, 30.8) respectively. Removal of high CRH pregnancies reduced the OR estimates by nearly half, i.e. MVI aOR = 1.9 (95% CI: 0.34, 10.9), FVO aOR = 6.0 (95% CI: 1.3, 28.6). MVI, FVI and MVD were each associated with greater odds of non-SGA/preterm, but the aORs showed little change after removing high CRH pregnancies.Conclusions: Obstructive placental vascular pathologies in maternal or fetal vessels are associated with SGA. High CRH levels coincided with a portion of pregnancies that share these complications, particularly among pregnancies that also ended prematurely.

Placental pathology, corticotropin‐releasing hormone (CRH), and fetal growth in the Pregnancy Outcomes and Community Health (POUCH) cohort

ObjectiveTo examine the associations of five histopathology‐based placental pathology constructs (maternal vascular – obstructive [MVO]; fetal vascular – obstructive [FVO]; maternal vascular – disturbance of integrity [MVI]; fetal vascular – disturbance of integrity [FVI]; maternal vascular – developmental [MVD]) and second trimester corticotropin‐releasing hormone (CRH) levels with birthweight‐for‐gestational age z‐score (BW/GA).MethodsWe studied 1,154 women in the Pregnancy Outcomes and Community Health (POUCH) study, a community‐based pregnancy cohort in Michigan. Using survey weights to account for the POUCH sampling scheme, we conducted multivariable linear regression to quantify differences and 95% confidence intervals (CI) in BW/GA with respect to evidence of placental pathology (yes vs. no), while also accounting for pre‐pregnancy BMI, race, gestational diabetes, and smoking habits.ResultsMedian age at enrollment was 26.7 ± 0.2 years. The majority (67.3%) of women were White, and 22% were African American. Mean ± SD BW/GA was 0.13 ± 0.04. In the overall sample, only MVO was associated with BW/GA (−0.53 [95% CI: −0.76, −0.31]). Stratification by preterm delivery status (n = 286 vs. 868) revealed that MVO corresponded with lower BW/GA in both term (−0.52 [95% CI: −0.77, −0.28] z‐scores lower BW/GA) and preterm births (−0.59 [95% CI: −0.99, −0.19] z‐score lower BW/GA), while FVO was related to lower BW/GA among preterm births only (−0.42 [95% CI: −0.72, −0.13] z‐scores). We observed evidence for effect modification by CRH for MVO, FVO, and FVI among preterm births, thus we further explored relations of CRH (Q1 as lowest, Q2+3 as referent, Q4 as highest) with BW/GA by placental pathology status, only among preterm deliveries. Among mother‐infant dyads with MVO and FVO, higher CRH was associated with 0.80 (95% CI: 0.07, 1.53) and 1.05 (95% CI: 0.51, 1.59) z‐scores lower BW/GA as compared to their counterparts with CRH in the middle quartiles. Among participants with FVI, lower CRH was associated with 0.53 (95% CI: 0.12, 0.95) z‐scores higher BW/GA.ConclusionsOur findings suggest that (1) maternal vascular obstructive complications are related to poor intrauterine growth regardless of preterm birth status, and (2) high CRH may be a biomarker of poor intrauterine growth in pregnancies that culminate in preterm delivery and exhibit placental pathology related to obstruction of the maternal and fetal circulations.

Maternal mid-pregnancy lipids and birthweight.

To describe associations between maternal lipids and birthweight and to determine whether pre-pregnancy body mass index (BMI) modifies these associations. Cohort study. Multiple communities in Michigan, USA. Participants were a sub-cohort of women from the multi-community Pregnancy Outcomes and Community Health (POUCH) study (1998-2004). Maternal total cholesterol, high-density lipoprotein (HDLc), and low-density lipoprotein (LDLc) cholesterol, and triglycerides were assessed at 16-27 weeks' gestation. Women were classified as having normal (< 25 kg/m(2) ) or overweight/obese (≥ 25 kg/m(2) ) pre-pregnancy BMI. Sex- and gestational-age-specific body weight z-score (BWz). Regression models examined associations among lipids (low: 1st quartile, referent: middle quartiles, high: 4th quartile) and BWz for the total sample and stratified by pre-pregnancy BMI. In adjusted analyses (n = 1207), low HDLc was associated with lower BWz (β = -0.23, 95% CI -0.40 to -0.06), whereas high triglycerides were associated with higher BWz (β = 0.23, 95% CI 0.06-0.41). Once stratified by pre-pregnancy BMI, low total cholesterol was associated with lower BWz in normal BMI women (β = -0.25, 95% CI -0.47 to -0.03), whereas in overweight/obese BMI women, high HDLc was inversely (β = -0.29, 95% CI -0.54 to -0.04) and high triglycerides were directly associated with BWz (β = 0.32, 95% CI 0.07-0.54). Removing women with gestational diabetes/hypertensive disorders did not alter the results. The associations between maternal lipids and BWz vary by lipid measure and pre-pregnancy BMI. Future work should examine whether lipids and pre-pregnancy BMI make unique contributions to the fetal programming of disease.

Abstract P164: Blood Pressure During Pregnancy and Risk of Hypertension Later in Life: A Longitudinal Study of POUCHMoms

Objectives: Hypertensive disorders in pregnancy carry a long-term risk of cardiovascular disease (CVD) for women. However, future hypertension status among pregnant women who have moderately elevated blood pressure (MEBP), that does not meet criteria for hypertensive disorders is unknown. We, therefore, investigated the risk of later hypertension among women with MEBP in pregnancy in addition to those diagnosed with gestational hypertensive disorders. Methods: Data are from the Pregnancy Outcomes and Community Health (POUCH) study, which enrolled pregnant women from 52 clinics in 5 Michigan Communities (1998-2004). We included 667 women with abstracted gestational BP measurements who also participated in the POUCHMoms follow-up 7-15 years later. MEBP was defined as systolic BP (SBP) ≥120mmHg or diastolic BP (DBP) ≥80mmHg among pregnant women who did not have a hypertensive disorder. Hypertensive disorders were defined as at least two SBP measurements ≥140 or DBP measurements ≥90 or regular use of anti-hypertensives, with or without proteinuria. Weighted multinomial logistic regression models were run to estimate the odds of prehypertension or hypertension at follow-up, before and after controlling for maternal prenatal confounders (e.g. age, parity, race) and time between pregnancy and follow-up. Results: The majority of participants (59.6%) met the criteria for MEBP which was significantly associated with hypertension at follow-up before and after adjustment for confounders (AOR=2.76; 95% CI 1.40, 5.46). Significant associations were seen for MEBP first identified prior to 20 weeks, and for MEBP observed due to elevated SBP either alone or in conjunction with elevated DBP. As expected, gestational hypertensive disorders also were associated with increased odds of hypertension at follow-up (AOR=16.99; 95% CI 6.11, 47.24). All of the above relationships held when body mass index (BMI) at follow-up was added into the models. Conclusions: Moderately elevated blood pressure in pregnancy may be a risk factor for hypertensive disorders later in life and may identify a group of women who need closer surveillance for CVD risk in the years following pregnancy. Elevated SBP appears to play a more influential role than DBP in the observed association.

Body mass index is associated with appropriateness of weight gain but not leisure-time physical activity during pregnancy.

Little is known about how leisure-time physical activity (LTPA) influences gestational weight gain (GWG) among body mass index (BMI) categories. The purpose of this study was to examine the relationship between pregnancy LTPA and the proportion of normal, overweight, and obese women who meet GWG recommendations. Participants included 449 subcohort women from the Pregnancy Outcomes and Community Health (POUCH) study. LTPA was collapsed into 3 categories [(None, < 7.5 kcal/kg/wk (low), ≥ 7.5 kcal/kg/wk (recommended)]. GWG was categorized according to IOM recommendations (low, recommended, or excess). Chi-square and logistic regression analyses were used to evaluate relationships among LTPA, BMI, and GWG. Overweight women were more likely to have high GWG vs. normal weight women (OR = 2.3, 95% CI 1.3-4.0). Obese women were more likely to experience low GWG (OR = 7.3, 95% CI 3.6-15.1; vs. normal and overweight women) or excess GWG (OR = 3.5, 95% CI 1.9-6.5; vs. normal weight women). LTPA did not vary by prepregnancy BMI category (P = .55) and was not related to GWG in any prepregnancy BMI category (P = .78). Regardless of prepregnancy BMI, LTPA did not affect a woman's GWG according to IOM recommendations. Results may be due to LTPA not differing among BMI categories.

Mid‐pregnancy maternal leptin levels, birthweight for gestational age and preterm delivery

Maternal blood leptin levels are positively associated with adiposity. Recent studies suggest that leptin is also abundantly produced by the placenta and may function as a regulator of foetal growth. Our goal was to examine mid-pregnancy levels of leptin in maternal blood in relation to birthweight for gestational age (BW/GA) and timing of delivery after accounting for maternal prepregnancy body mass index (prepreg-BMI) and pregnancy complications. Data were from 1304 subcohort mother/infant pairs who participated in the Pregnancy Outcomes and Community Health (POUCH) Study (1998-2004). Leptin levels, measured at 16-27 weeks' gestation, were log-transformed. Geometric mean (GMean) leptin levels were estimated by weighted linear regression with gestational age at blood draw as a covariate. GMean was re-transformed to the original scale for reporting. Using the GMeans leptin in mothers of term appropriate-for-gestational age (AGA) neonates as the referent (25·2 μg/l), we observed lower levels in mothers of preterm-AGA (21·9 μg/l), term small-for-gestational age (SGA) (20·3 μg/l) and preterm-SGA neonates (21·7 μg/l). Results were largely unchanged after adjustment for prepreg-BMI. Leptin levels were higher in mothers who delivered large-for-gestational age (LGA) neonates, both preterm (33·6 μg/l) and term (29·1 μg/l), but the GMeans were markedly attenuated after adjustment for prepreg-BMI. The association between BW/GA and maternal leptin levels after adjustment for prepreg-BMI may represent: (i) a residual effect of maternal adiposity that is not fully captured by BMI; and/or (ii) variation in placental leptin levels entering the maternal circulation. In conclusion, mid-pregnancy maternal blood leptin levels may be an early indicator of foetal growth status.

Late-Preterm Birth by Delivery Circumstance and Its Association With Parent-Reported Attention Problems in Childhood

Late-preterm birth (LPB, 34-36 wk) has been associated with an increased risk of attention problems in childhood relative to full-term birth (FTB, ≥37 wk), but little is known about factors contributing to this risk. The authors investigated the contributions of clinical circumstances surrounding delivery using follow-up data from the Pregnancy Outcomes and Community Health (POUCH) Study. Women who delivered late preterm or full term and completed the sex- and age-referenced Conners' Parent Rating Scales-Short Form: Revised were included in the present analysis (N = 762; children's age, 3-9 y). The Conners' Parent Rating Scales-Short Form: Revised measures dimensions of behavior linked to attention problems, including oppositionality, inattention, hyperactivity, and a global attention problem index. Using general linear models, the authors evaluated whether LPB subtype (medically indicated [MI] or spontaneous) was associated with these dimensions relative to FTB. After adjustment for parity, sociodemographics, child age, and maternal symptoms of depression and serious mental illness during pregnancy and at the child survey, only MI LPB was associated with higher hyperactivity and global index scores (mean difference from FTB = 3.8 [95% confidence interval {CI}: 0.5, 7.0] and 3.1 [95% CI 0.0, 6.2]). These findings were largely driven by children between 6 and 9 years. Removal of women with hypertensive disorders during pregnancy (N = 85) or placental findings related to hypertensive conditions (obstruction, decreased maternal spiral artery conversion; N = 134) reduced the differences below significance thresholds. Among LPBs, only MI LPB was associated with higher levels of parent-reported childhood attention problems, suggesting that complications motivating medical intervention during the late-preterm period mark increased risk for such problems. Hypertensive disorders seem to play a role in these associations.

Leisure-Time Physical Activity in Pregnancy and the Birth Weight Distribution: Where Is the Effect?

Leisure-time physical activity (LTPA) is recommended during pregnancy and has been associated with lower risk of delivering a large infant. We sought to characterize the effect of LTPA across the entire birth weight distribution. Women enrolled in the Pregnancy Outcomes and Community Health (POUCH) Study (1998-2004) were followed-up in 2007. Follow-up efforts were extensive for a subcohort and minimal for the remainder (nonsubcohort). Thus, 596 subcohort and 418 nonsubcohort women who delivered at term participated. Offspring were categorized as small-, appropriate-, or large-for-gestational-age (SGA, AGA, and LGA, respectively) based on gender and gestational age-specific birth weight z-scores (BWz). At follow-up, women recalled pregnancy LTPA and were classified as inactive, insufficiently active or meeting LTPA recommendations. Linear, logistic, and quantile regression analyses were conducted separately by subcohort status. Meeting LTPA recommendations decreased odds of LGA significantly among the nonsubcohort (aOR = 0.30, 95% CI: 0.14-0.64) and nonsignificantly among the subcohort (aOR = 0.68, 95% CI: 0.34-1.34). In quantile regression, meeting LTPA recommendations reduced BWz among the upper quantiles in the nonsubcohort. LTPA during pregnancy lowered odds of LGA and reduced BWz among the upper quantiles, without shifting the entire distribution. LTPA during pregnancy may be useful for reducing risks of large fetal size.

Interplay of cytokine polymorphisms and bacterial vaginosis in the etiology of preterm delivery.

Recent findings suggest that the association between inflammation-related genes and preterm delivery may be stronger in the presence of bacterial vaginosis (BV). Tumor necrosis factor-alpha (TNFα) and interleukin 1-beta (IL-1β) are pro-inflammatory cytokines capable of inducing preterm labor in non-human primates. In this study the authors tested associations among two TNFα promoter polymorphisms (-G308A and -G238A), a single IL-1β polymorphism (+C3954T), vaginal microbial findings, and risk of preterm delivery. Data were from the Pregnancy Outcomes and Community Health (POUCH) Study (n=777 term and n=230 preterm deliveries). Vaginal smears collected at mid-pregnancy (15-27 weeks gestation) were scored according to Nugent's criteria. A Nugent score of ≥ 4 was modeled as the cut-point for intermediate and positive BV. Logistic regression was used to estimate odds ratios for associations among independent covariates (vaginal flora, genotype) and preterm delivery. Results showed that women with a Nugent score of≥ 4 and the TNFα -238 A/G or A/A were at increased risk of delivering preterm (race/ethnicity adjusted OR 2.6, 95% CI 1.2, 5.8). The p-value for the genotype and Nugent score interaction=0.02. This study points to one more example of a potential gene-environment interaction in a preterm delivery pathway. Future tests of this finding will determine the robustness of these results.

Levels of maternal serum corticotropin-releasing hormone (CRH) at midpregnancy in relation to maternal characteristics

Corticotropin-releasing hormone (CRH) in maternal blood originates primarily from gestational tissues and elevated levels in midpregnancy have been linked to adverse pregnancy outcomes. Investigators have hypothesized that high levels of maternal stress might lead to elevated CRH levels in pregnancy. Yet a few studies have measured maternal CRH levels among subgroups of women who experience disproportionate socioeconomic disadvantage, such as African-American and Hispanic women, and found that these groups have lower CRH levels in pregnancy. Our goal was to identify maternal characteristics related to CRH levels in midpregnancy and examine which if any of these factors help to explain race differences in CRH levels. The Pregnancy Outcomes and Community Health (POUCH) Study prospectively enrolled women at 15-27 weeks' gestation from 52 clinics in five Michigan communities (1998-2004). Data from the POUCH Study were used to examine maternal demographics, anthropometrics, health behaviors, and psychosocial factors (independent variables) in relation to midpregnancy blood CRH levels modeled as logCRHpg/ml (dependent variable). Analyses were conducted within a sub-cohort from the POUCH Study (671 non-Hispanic Whites, 545 African-Americans) and repeated in the sub-cohort subset with uncomplicated pregnancies (n=746). Blood levels of CRH and independent variables were ascertained at the time of enrollment. All regression models included week of enrollment as a covariate. In addition, final multivariate regression models alternately incorporated different psychosocial measures along with maternal demographics and weight. Psychosocial variables included measures of current depressive symptoms, perceived stress, coping style, hostility, mastery, anomie, and a chronic stressor (history of abuse as a child and adult). In sub-cohort models, the adjusted mean log CRH level was significantly lower in African-Americans vs. non-Hispanic Whites; the difference was -0.48pg/ml (P<0.01). This difference was reduced by 21% (-0.38pg/ml, P<0.01) after inclusion of other relevant covariates. Adjusted mean log CRH levels were also lower among women with <12 years vs. >or=12 years of education (minimal difference=-0.19pg/ml, P<0.05), and among women with high levels of depressive symptoms who did not use antidepressants vs. women with lower levels of depressive symptoms and no antidepressant use (minimal difference=-0.13pg/ml, P<0.01). Log CRH levels were inversely associated with maternal weight (-0.03pg/ml per 10 pound increase, P<.05) but unrelated to smoking and all other psychosocial measures. Results were similar in the subset of women with uncomplicated pregnancies, except that lower CRH levels were also linked to higher perceived stress. African-American women have lower blood CRH levels at midpregnancy and the race difference in CRH levels is reduced modestly after adjustment for other maternal characteristics. CRH levels were not elevated among women with high levels of perceived stress or more chronic stressors. The inverse association between CRH levels and maternal weight is likely due to a hemodilution effect. Relations among maternal CRH levels and maternal race, educational level, and depressive symptoms are difficult to explain and invite further investigation. Our results highlight a group of covariates that merit consideration in studies that address CRH in the context of pregnancy and/or post-partum complications.

Hostility and anomie: Links to preterm delivery subtypes and ambulatory blood pressure at mid-pregnancy

Underlying maternal vascular disease has been implicated as one of several pathways contributing to preterm delivery (PTD) and psychosocial factors such as hostility, anomie, effortful coping, and mastery may be associated with PTD by affecting maternal vascular health. Using data from the Pregnancy Outcomes and Community Health (POUCH) study, we included 2018 non-Hispanic White and 743 African American women from 52 clinics in five Michigan, USA communities. Women were interviewed at 15–27 weeks' gestation and followed to delivery. We found that relations between psychosocial factors and PTD subtypes (i.e. medically indicated, premature rupture of membranes, spontaneous labor) varied by race/ethnicity and socio-economic position (Medicaid insurance status). Among African American women not insured by Medicaid, anomie levels in mid-pregnancy were positively associated with medically indicated PTD after adjusting for maternal age and education. Among all women not insured by Medicaid, hostility levels were positively associated with spontaneous PTD after adjusting for maternal race/ethnicity, age, and education. Failure to detect links between psychosocial factors and PTD risk in poorer women may be due to their excess risk in multiple PTD pathways and/or a more complex web of contributing risk factors.In a subset of 395 women monitored for blood pressure, anomie scores were positively associated with systolic blood pressure and heart rate and hostility scores were positively associated with systolic and diastolic blood pressure, heart rate and mean arterial pressure in models that included time, awake/asleep, race/ethnicity, and age as covariates. Further adjustment for body mass index and smoking attenuated the anomie-vascular relations but had little effect on the hostility-vascular relations. Overall this study of pregnant women provides some physiologic evidence to support findings linking levels of anomie and hostility with risk of PTD.

Maternal fish consumption, mercury levels, and risk of preterm delivery.

BackgroundPregnant women receive mixed messages about fish consumption in pregnancy because unsaturated fatty acids and protein in fish are thought to be beneficial, but contaminants such as methylmercury may pose a hazard.MethodsIn the Pregnancy Outcomes and Community Health (POUCH) study, women were enrolled in the 15th to 27th week of pregnancy from 52 prenatal clinics in five Michigan communities. At enrollment, information was gathered on amount and category of fish consumed during the current pregnancy, and a hair sample was obtained. A segment of hair closest to the scalp, approximating exposure during pregnancy, was assessed for total mercury levels (70–90% methylmercury) in 1,024 POUCH cohort women.ResultsMercury levels ranged from 0.01 to 2.50 μg/g (mean = 0.29 μg/g; median = 0.23 μg/g). Total fish consumption and consumption of canned fish, bought fish, and sport-caught fish were positively associated with mercury levels in hair. The greatest fish source for mercury exposure appeared to be canned fish. Compared with women delivering at term, women who delivered before 35 weeks’ gestation were more likely to have hair mercury levels at or above the 90th percentile (≥ 0.55 μg/g), even after adjusting for maternal characteristics and fish consumption (adjusted odds ratio = 3.0; 95% confidence interval, 1.3–6.7).ConclusionThis is the first large, community-based study to examine risk of very preterm birth in relation to mercury levels among women with low to moderate exposure. Additional studies are needed to see whether these findings will be replicated in other settings.

Depressive symptoms in mid‐pregnancy, lifetime stressors and the 5‐HTTLPR genotype

Few studies of gene-environment interactions for the serotonin transporter promoter polymorphism (5-HTTLPR), life stressors and depression have considered women separately or examined specific types of stressful life events. None have looked at depression during pregnancy. In the Pregnancy Outcomes and Community Health (POUCH) Study, women were queried about history of stressful life events and depressive symptoms at the time of enrollment (15-27 weeks gestation). Stressful life events were grouped a priori into "subconstructs" (e.g. economic, legal, abuse, loss) and evaluated by subconstruct, total subconstruct score and total stressful life event score. The effect of genotype on the association between stressful life events and elevated depressive symptoms was assessed in 568 white non-Hispanic participants. The relationship between exposure to abuse and elevated depressive symptoms was more pronounced in the s/s group (OR = 24.5) than in the s/l group (OR = 3.0) and the l/l group (OR = 7.7), but this significant interaction was detected only after excluding 73 (13%) women with recent use of psychotropic medications. There was no evidence of gene-environment interaction in analytic models with other stressful life events subconstructs, total subconstruct score or total stressful life events score. These data offer modest support to other reports of gene-environment interaction and highlight the importance of considering specific stressful life events.

Assessing mid‐trimester salivary cortisol levels across three consecutive days in pregnant women using an at‐home collection protocol

The Pregnancy Outcomes and Community Health (POUCH) Study enrolled women in their 15th to 27th week of pregnancy from 52 prenatal clinics located in five communities. After the study began, an at-home protocol to measure maternal stress was added, which included collection of urine and saliva twice a day (waking = AM, bedtime = PM) for three consecutive days, and completion of a daily diary. The at-home protocol was in place for 2852 POUCH participants at enrollment, and 81.3% (n = 2318) consented and returned samples and diary. For these analyses, salivary cortisol was analysed in a subset of 846 women who delivered at term. Day-to-day correlation coefficients for AM cortisol (0.45-0.55) exceeded those for PM cortisol (0.31-0.43). Study diaries indicated that there was variation in the time interval between waking and sample collection. Analyses of discrete intervals showed the same awakening response pattern in cortisol levels that has been reported in studies with serial AM sampling. The adjusted mean AM cortisol (microg/dL) was 0.506 at 0-15 min post-waking, 0.544 at 16-30 min (P < 0.05), 0.582 at 31-60 min (P < 0.01), and 0.515 at >60 min post-waking. In addition, adjusted mean AM cortisol in samples collected at or before 9 a.m. was higher than that in samples collected after 9 a.m. (0.564 vs. 0.510 microg/dL, P < 0.01). Among working women, adjusted mean AM cortisol was higher on work days than non-work days (0.564 vs. 0.489 microg/dL, P < 0.01), and in multiparae compared with primiparae (0.551 vs. 0.502 microg/dL, P = 0.07). The parity effect was not evident in non-working women. The adjusted mean PM cortisol significantly increased as week of pregnancy at sampling increased, but was not significantly related to time of collection, work day and parity. Factors influencing AM and PM cortisol levels in pregnancy appear to differ. In studies of AM cortisol levels, it is important to gather data on time of sample collection, interval from waking to sample collection, parity and work.

A Life Course Perspective on Depressive Symptoms in Mid-Pregnancy

To examine the prevalence of depressive symptoms in mid-pregnancy and their relation to life circumstances across the life course in a community-based sample. The Pregnancy Outcomes and Community Health (POUCH) Study enrolled women at 16-26 weeks' gestation from 52 clinics in five Michigan communities. At enrollment women completed a screening instrument for depressive symptoms (CES-D) and questions about life circumstances covering three "periods," i.e. previous 6 months, adulthood, and childhood. Questions were grouped into sub-constructs (e.g., abuse, economic, substance use, loss, and legal) for each "period" and evaluated in relation to CES-D scores. Analyses included 1321 POUCH participants divided into three subgroups: teens; women > or =20 years insured by Medicaid (disadvantaged); and women > or =20 years not insured by Medicaid (advantaged). A positive CES-D screen (> or =16) was more common in teens (46%) and disadvantaged women (47%) than in advantaged women (23%). Recent problems (previous 6 months) with abuse, economics, and substance use in someone close were each associated with higher adjusted mean CES-D scores (2.3-7.5 increase) in the three subgroups of women. In life course analyses, abuse and substance use in teens, and abuse and economic problems in disadvantaged and advantaged women were strongly linked to higher adjusted mean CES-D scores when these problems occurred both in childhood and adulthood (range 2.2-7.1 increase), whereas the associations were more modest when problems were confined to childhood. Strategies for addressing the public health problem of depressive symptoms in mid-pregnancy will benefit from a life course perspective.

Pregnancy outcomes and community health: the POUCH study of preterm delivery.

In light of the social/ethnic disparity in preterm delivery (PTD) rates, the Pregnancy Outcomes and Community Health (POUCH) Study takes a broad view of the determinants of PTD by attempting to link underlying biological and psychosocial factors. The relationships between placental pathology, maternal biomarkers, and antecedent psychosocial factors are evaluated in three hypothesised pathways of PTD - one characterised primarily by infection, one by maternal vascular disease, and one by premature elevations in corticotropin releasing hormone in the absence of histological evidence of placental pathology. Within each pathway, an emphasis is placed on understanding the roles of stress and of maternal serum alpha-fetoprotein, an early biomarker associated with PTD. The POUCH Study enrolls pregnant women from five Michigan communities. Information about these women and their environments is gathered through detailed interviews and collection of biological samples including hair, urine, saliva, blood, vaginal fluid, and vaginal smear at 15-26 weeks of gestation. We have chosen to focus on the second trimester--a time when pathological processes may have evolved to a detectable stage, but generally before the onset of biological changes that accompany labour. This focus is consistent with the long-range goal of early detection/intervention and prevention of PTD.