Perinatal health effects of herbicides exposures in the United States: the Heartland Study, a Midwestern birth cohort study

BACKGROUND

The objective of the Heartland Study is to address major knowledge gaps concerning the health effects of herbicides on maternal and infant health. To achieve this goal, a two-phased, prospective longitudinal cohort study is being conducted. Phase 1 is designed to evaluate associations between biomarkers of herbicide concentration and pregnancy/childbirth outcomes. Phase 2 is designed to evaluate potential associations between herbicide biomarkers and early childhood neurological development.

METHODS

People (target enrollment of 2,000) who are seeking prenatal care, are ages 18 or older, and are ≤ 20 + 6 weeks gestation will be eligible for recruitment. The Heartland Study will utilize a combination of questionnaire data and biospecimen collections to meet the study objectives. One prenatal urine and buccal sample will be collected per trimester to assess the impact of herbicide concentration levels on pregnancy outcomes. Infant buccal specimens will be collected post-delivery. All questionnaires will be collected by trained study staff and clinic staff will remain blinded to all individual level research data. All data will be stored in a secure REDCap database. Hospitals in the agriculturally intensive states in the Midwestern region will be recruited as study sites. Currently participating clinical sites include Indiana University School of Medicine- affiliated Hospitals in Indianapolis, Indiana; Franciscan Health Center in Indianapolis, Indiana; Gundersen Lutheran Medical Center in La Crosse, Wisconsin, and University of Iowa in Iowa City, Iowa. An anticipated 30% of the total enrollment will be recruited from rural areas to evaluate herbicide concentrations among those pregnant people residing in the rural Midwest. Perinatal outcomes (e.g. birth outcomes, preterm birth, preeclampsia, etc.) will be extracted by trained study teams and analyzed for their relationship to herbicide concentration levels using appropriate multivariable models.

DISCUSSION

Though decades of study have shown that environmental chemicals may have important impacts on the health of parents and infants, there is a paucity of prospective longitudinal data on reproductive impacts of herbicides. The recent, rapid increases in herbicide use across agricultural regions of the United States necessitate further research into the human health effects of these chemicals, particularly in pregnant people. The Heartland Study provides an invaluable opportunity to evaluate health impacts of herbicides during pregnancy and beyond.

TRIAL REGISTRATION

The study is registered at clinicaltrials.gov, NCT05492708 with initial registration and release 05 August, 2022.

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

Healthy preconception and early-pregnancy lifestyle and risk of preterm birth: a prospective cohort study

BACKGROUND

Preterm birth (PTB) remains a leading cause of neonatal mortality and long-term morbidity. Individual factors have been linked to PTB risk. The impact of a healthy lifestyle, with multiple modifiable prenatal factors, remains unknown.

OBJECTIVES

We aimed to examine the associations of preconceptional and early-pregnancy low-risk modifiable factors (individually and in combination) with PTB risk.

METHODS

This prospective cohort study included 2449 women with singleton pregnancies in the Pregnancy Environment and Lifestyle Study. PTB was defined as ultrasound-confirmed obstetric estimate-based gestational age at delivery <37 wk. A set of low-risk modifiable factors were identified: healthy weight (prepregnancy BMI: 18.5-24.9 kg/m2) based on clinical measurements and high-quality diet (Alternate Healthy Eating Index-Pregnancy score ≥75th percentile) and low-to-moderate stress during early pregnancy (Perceived Stress Scale score <75th percentile) assessed at gestational weeks 10-13. Poisson regression estimated adjusted relative risk (aRR) of PTB in association with individual and combined low-risk modifiable prenatal factors, adjusting for sociodemographic, clinical, and other prenatal factors.

RESULTS

One hundred and sixty women (6.5%) delivered preterm. Risk of PTB was lower among women who had a healthy weight (aRR: 0.58; 95% CI: 0.39, 0.86), high-quality diet (aRR: 0.68; 95% CI: 0.39, 0.99), and low-to-moderate stress (aRR: 0.60; 95% CI: 0.41, 0.88). Women with 1, 2, or 3 low-risk modifiable prenatal factors compared with none had a 38% (aRR: 0.72; 95% CI: 0.45, 1.16), 51% (aRR: 0.49; 95% CI: 0.29, 0.84), or 70% (aRR: 0.30; 95% CI: 0.13, 0.70) lower PTB risk, respectively. Associations of having ≥1 low-risk factor with PTB risk were more pronounced for medically indicated than for spontaneous PTB and for late than for early or moderate PTB. Associations also varied by race or ethnicity, although with overlapping 95% CIs.

CONCLUSIONS

A healthy prenatal lifestyle with multiple low-risk modifiable factors was associated with lower risk of PTB. Our findings may inform multicomponent preconceptional or early-pregnancy prevention strategies to mitigate PTB risk.

Alcohol Intake in Early Pregnancy and Spontaneous Preterm Birth: A Cohort Study

BACKGROUND

Limited research has addressed whether maternal alcohol intake in early pregnancy increases the risk of spontaneous preterm birth. In the current study, we examined how alcohol binge drinking and weekly alcohol intake in early pregnancy were associated with spontaneous preterm birth in a contemporary cohort of Danish women.

METHODS

We included 15,776 pregnancies of 14,894 women referred to antenatal care at Copenhagen University Hospital, Denmark, between 2012 and 2016. Self-reported alcohol intake in early pregnancy was obtained from a Web-based questionnaire completed prior to the women's first visit at the department. Information on spontaneous preterm birth was extracted from the Danish Medical Birth Register. Adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) of spontaneous preterm birth according to self-reported alcohol binge drinking and weekly intake of alcohol in early pregnancy were derived from Cox regression.

RESULTS

Women reporting 1, 2, and ≥ 3 binge drinking episodes had an aHR for spontaneous preterm birth of 0.88 (95% CI 0.68 to 1.14), 1.34 (95% CI 0.98 to 1.82), and 0.93 (95% CI 0.62 to 1.41), respectively, compared to women with no binge drinking episodes. Women who reported an intake of ≥ 1 drink per week on average had an aHR for spontaneous preterm birth of 1.09 (95% CI 0.63 to 1.89) compared to abstainers. When restricting to nulliparous women or cohabiting women with ≥ 3 years of higher education, this estimate was 1.28 (95% CI 0.69 to 2.40) and 1.20 (95% CI 0.67 to 2.15), respectively.

CONCLUSION

We found no evidence that maternal alcohol intake in early pregnancy was associated with a higher risk of spontaneous preterm birth, neither for alcohol binge drinking nor for a low average weekly intake of alcohol.

Association between maternal alcohol consumption during pregnancy and risk of preterm delivery: the Japan Environment and Children's Study

OBJECTIVE

To examine the association between maternal alcohol consumption during pregnancy and the risk of preterm delivery.

DESIGN

Prospective cohort study.

SETTING

The Japan Environment and Children's Study (JECS).

POPULATION

A total of 94 349 singleton pregnancies.

METHODS

Participants completed questionnaires detailing alcohol consumption during the first trimester and during the second and third trimesters. Participants were divided into four categories according to alcohol consumption (non-drinkers, consumers of 1-149 g, 150-299 g and ≥300 g ethanol/week). We examined the effect of alcohol consumption during different stages of pregnancy on the risk of preterm delivery. Odds ratios (OR) and 95% CI were calculated relative to non-drinkers using logistic regression.

MAIN OUTCOME MEASURES

Medical record-based preterm delivery.

RESULTS

Alcohol consumption during the second and third trimesters, but not during the first trimester, was associated with increased risk of preterm delivery. Heavy alcohol consumption (≥300 g ethanol/week) during the second and third trimesters was associated with a four-fold higher risk compared with non-drinkers (multivariable OR 4.52; 95% CI 1.68-12.2). Light alcohol consumption (1-149 g ethanol/week) tended to be associated with lower risk of preterm delivery (multivariable OR 0.78; 95% CI 0.60-1.00).

CONCLUSIONS

Heavy alcohol consumption during the second and third trimesters was associated with increased risk of preterm delivery among pregnant women.

TWEETABLE ABSTRACT

Heavy drinking during pregnancy may increase the risk of preterm delivery.

Pregnancy outcome in more than 5000 births to women with viral hepatitis: a population-based cohort study in Sweden

Previous studies have shown inconsistent results with respect to hepatitis B (HBV), hepatitis C (HCV) and pregnancy outcome. The aim of this study was to investigate pregnancy outcome in women with HBV or HCV. In a nationwide cohort of births between 2001 and 2011 we investigated the risks of adverse pregnancy outcomes in 2990 births to women with HBV and 2056 births to women with HCV using data from Swedish healthcare registries. Births to women without HBV (n = 1090 979), and births without HCV (n = 1091 913) served as population controls. Crude and adjusted relative risks (aRR) were calculated using Poisson regression analysis. Women with HCV were more likely to smoke (46.7 vs. 8.0%) and to have alcohol dependence (18.9 vs. 1.3%) compared with population controls. Most women with HBV were born in non-Nordic countries (91.9%). Maternal HCV was associated with a decreased risk of preeclampsia (aRR: 0.39, 95% CI: 0.24–0.64), but an increased risk of preterm birth (aRR: 1.32, 95% CI: 1.08–1.60) and late neonatal death (7–27 days: aRR: 3.79, 95% CI: 1.07–13.39) Preterm birth were also more common in mothers with HBV, aRR: 1.21 (95% CI: 1.02–1.45). Both HBV and HCV are risk factors for preterm birth, while HCV seems to be associated with a decreased risk for preeclampsia. Future studies should corroborate these findings.

AISF position paper on liver disease and pregnancy

The relationship between liver disease and pregnancy is of great clinical impact. Severe liver disease in pregnancy is rare; however, pregnancy-related liver disease is the most frequent cause of liver dysfunction during pregnancy and represents a severe threat to foetal and maternal survival. A rapid differential diagnosis between liver disease related or unrelated to pregnancy is required in women who present with liver dysfunction during pregnancy. This report summarizes the recommendation of an expert panel established by the Italian Association for the Study of the Liver (AISF) on the management of liver disease during pregnancy. The article provides an overview of liver disease occurring in pregnancy, an update on the key mechanisms involved in its pathogenesis, and an assessment of the available treatment options. The report contains in three sections: (1) specific liver diseases of pregnancy; (2) liver disease occurring during pregnancy; and (3) pregnancy in patients with pre-existing chronic liver disease. Each topic is discussed considering the most relevant data available in literature; the final statements are formulated according to both scientific evidence and clinical expertise of the involved physicians, and the AISF expert panel recommendations are reported.

Pregnancy outcomes and birth defects from an antiretroviral drug safety study of women in South Africa and Zambia

OBJECTIVE

To evaluate the safety of combination antiretroviral therapy (ART) in conception and pregnancy in different health systems.

DESIGN

A pilot ART registry to measure the prevalence of birth defects and adverse pregnancy outcomes in South Africa and Zambia.

METHODS

HIV-infected pregnant women on ART prior to conception were enrolled until delivery, and their infants were followed until 1 year old.

RESULTS

Between October 2010 and April 2011, 600 women were enrolled. The median CD4 cell count at study enrollment was lower in South Africa than Zambia (320 vs. 430 cells/μl; P < 0.01). The most common antiretroviral drugs at the time of conception included stavudine, lamivudine, and nevirapine. There were 16 abortions (2.7%), one ectopic pregnancy (0.2%), 12 (2.0%) stillbirths, and 571 (95.2%) live infants. Deliveries were more often preterm (29.7 vs. 18.4%; P = 0.01) and the infants had lower birth weights (2900 vs. 2995 g; P = 0.11) in Zambia compared to South Africa. Thirty-six infants had birth defects: 13 major and 23 minor. There were more major anomalies detected in South Africa and more minor ones in Zambia. No neonatal deaths were attributed to congenital birth defects.

CONCLUSIONS

An Africa-specific, multi-site antiretroviral drug safety registry for pregnant women is feasible. Different prevalence for preterm delivery, delivery mode, and birth defect types between women on preconception ART in South Africa and Zambia highlight the potential impact of health systems on pregnancy outcomes. As countries establish ART drug safety registries, documenting health facility limitations may be as essential as the specific ART details.

Preterm birth in the first pregnancy and risk of neonatal death in the second pregnancy: a propensity score-weighted matching approach

The study purpose was to assess the relationship between various grades of preterm birth (moderate preterm: 33-36 weeks; severe preterm: 27-32 weeks; extreme preterm: ≤ 26 weeks) in the first pregnancy and neonatal mortality (death within 28 days of birth; early: 0-7 days; late: 8-28 days) in the second pregnancy. Using the Missouri maternally-linked dataset (1989-2005), a population-based, retrospective cohort analysis with propensity score-weighted matching was conducted on mothers with two consecutive singleton live births (n = 310,653 women). Women with a prior preterm birth were more likely to subsequently experience neonatal death. The odds increased in a dose-dependent pattern with ascending severity of the preterm event in the first pregnancy (moderate preterm: AOR = 1.32; 95% CI: 1.10-1.60; severe preterm: AOR = 2.62; 95% CI: 2.01-3.41; extreme preterm: AOR = 5.84; 95% CI: 4.28-7.97; p value for trend < 0.001). However, the pathway for the relationship between prior preterm birth and subsequent neonatal mortality may be the recurrence of preterm birth.

Alcohol consumption during pregnancy and birth outcomes: the Kyushu Okinawa Maternal and Child Health Study

Background

A recent meta-analysis showed no relationships between light to moderate alcohol consumption during pregnancy and the risk of low birth weight (LBW), preterm birth (PTB), or small-for-gestational-age (SGA). Here, we present the first epidemiological study on this topic in Japan.

Methods

Study subjects were 1565 Japanese mothers with singleton pregnancies and the babies born from these pregnancies. Alcohol consumption during pregnancy was assessed using a self-administered diet history questionnaire. Alcohol consumption during pregnancy was classified into three categories (none, < 1 g/day, and ≥ 1 g/day).

Results

The mean birth weight of the babies was 3006.3 g. 7.7% were classified as LBW, 4.0% as PTB, and 7.8% as SGA. The range of maternal alcohol consumption during pregnancy was 0.0 to 11.7 g per day: 1356 (86.7%) mothers were abstainers and the 95th percentile value was 0.84 g per day. Compared with abstinence, alcohol consumption of 1.0 g or more per day during pregnancy was significantly associated with an increased risk of PTB with a significant positive linear trend: the adjusted OR for PTB associated with maternal alcohol consumption of 1.0 g or more per day was 2.58 (95% CI: 1.004 - 5.80, P for trend = 0.03). No significant relationships were observed between maternal alcohol consumption during pregnancy and the risk of LBW or SGA, and there was no material association between maternal alcohol consumption during pregnancy and birth weight.

Conclusions

This is the first study in Japan to show that maternal alcohol consumption during pregnancy of 1.0 g or more per day was significantly positively associated with the risk of PTB, but not LBW or SGA.

Estimated number of preterm births and low birth weight children born in the United States due to maternal binge drinking

The objective of this study was to estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. To estimate the aggregate burden of maternal binge drinking on preterm birth (PTB) and low birth weight (LBW) across American sociodemographic groups in 2008. A simulation model was developed to estimate the number of PTB and LBW cases due to maternal binge drinking. Data inputs for the model included number of births and rates of preterm and LBW from the National Center for Health Statistics; female population by childbearing age groups from the U.S. Census; increased relative risks of preterm and LBW deliveries due to maternal binge drinking extracted from the literature; and adjusted prevalence of binge drinking among pregnant women estimated in a multivariate logistic regression model using Behavioral Risk Factor Surveillance System survey. The most conservative estimates attributed maternal binge drinking to 8,701 (95% CI: 7,804-9,598) PTBs (1.75% of all PTBs) and 5,627 (95% CI 5,121-6,133) LBW deliveries in 2008, with 3,708 (95% CI: 3,375-4,041) cases of both PTB and LBW. The estimated rate of PTB due to maternal binge drinking was 1.57% among all PTBs to White women, 0.69% among Black women, 3.31% among Hispanic women, and 2.35% among other races. Compared to other age groups, women ages 40-44 had the highest adjusted binge drinking rate and highest PTB rate due to maternal binge drinking (4.33%). Maternal binge drinking contributed significantly to PTB and LBW differentially across sociodemographic groups.

Preterm birth and small for gestational age in relation to alcohol consumption during pregnancy: stronger associations among vulnerable women? Results from two large Western-European studies

BACKGROUND

Inconsistent data on the association between prenatal alcohol exposure and a range of pregnancy outcomes, such as preterm birth (PTB) and small for gestational age (SGA) raise new questions. This study aimed to assess whether the association between low-moderate prenatal alcohol exposure and PTB and SGA differs according to maternal education, maternal mental distress or maternal smoking.

METHODS

The Amsterdam Born Children and their Development (ABCD) Study (N = 5,238) and the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) (N = 16,301) are both large studies. Women provide information on alcohol intake in early pregnancy, 3 months postpartum and up to 17 years retrospectively. Multivariate logistic regression analyses and stratified regression analyses were performed to examine the association between prenatal alcohol exposure and PTB and SGA, respectively.

RESULTS

No association was found between any level of prenatal alcohol exposure (non-daily, daily, non-abstaining) and SGA. The offspring of daily drinkers and non-abstainers had a lower risk of PTB [ABCD: odds ratio (OR) 0.31, 95% confidence interval (CI) 0.13, 0.77; KiGGS: OR 0.75, 95% CI 0.57, 0.99]. Interactions with maternal education, maternal distress or maternal smoking were not significant.

CONCLUSIONS

Although these results should be interpreted with caution, both studies showed no adverse effects of low-moderate prenatal alcohol exposure on PTB and SGA, not even in the offspring of women who were disadvantaged in terms of low education, high levels of distress, or smoking during pregnancy.

Mothers with alcoholic liver disease and the risk for preterm and small-for-gestational-age birth

AIMS

To study pregnancy outcome in women with alcoholic liver disease (ALD).

METHODS

Using the Swedish nation-wide Patient and Medical Birth Registers, we investigated risk of adverse pregnancy outcome in 720 women diagnosed with ALD before and 1720 diagnosed after birth and compared them with 24 460 population-based control births.

RESULTS

Women with ALD diagnosed before or after birth were generally of higher age and body mass index, more likely to smoke cigarettes during pregnancy and to have a low socio-economic status compared with controls. Women diagnosed with ALD before birth had an increased risk of moderately and very preterm birth, adjusted odd ratio (OR) = 1.53 (95% confidence interval (CI): 1.37-1.72 and 1.15-2.06 95%), respectively. Infants of mothers with ALD before birth were more often small-for-gestational age, adjusted OR = 1.22 (95% CI: 1.05-1.43), and were at increased risk for low Apgar scores (<7) at 5 min, adjusted OR = 1.49 (95% CI: 1.15-1.92) compared with controls. Similar associations with slightly lower-risk estimates were found among women diagnosed with ALD after birth.

CONCLUSIONS

ALD is associated with adverse-birth outcomes, highlighting the importance of screening women for alcohol dependence in antenatal care.

Small size for gestational age and the risk for infant mortality in the subsequent pregnancy

PURPOSE

To examine the association between small for gestational age (SGA) in the first pregnancy and risk for infant mortality in the second pregnancy.

METHODS

This is a population-based, retrospective cohort study in which we used the Missouri maternally linked cohort dataset for 1978-2005. Analyses were restricted to women who had two singleton pregnancies during the study period. The exposure was SGA in the first pregnancy, whereas the primary outcome was infant mortality in the second pregnancy. Kaplan-Meier Estimate and Cox proportional hazard regression were conducted.

RESULTS

Infant mortality was significantly greater among mothers with previous SGA (P < .01). A persistent association of previous SGA with subsequent infant mortality was observed (adjusted hazard ratio [AHR] 1.35, 95% confidence interval [95% CI] 1.24-1.48). Race-specific data illustrated that black women with a previous SGA birth were 40% more likely to experience infant mortality (AHR 1.40, 95% CI 1.21-1.63) than their counterparts without a history of SGA, but white women with a previous SGA had an increased risk of 31% (AHR 1.31, 95% CI 1.17-1.46).

CONCLUSIONS

Women with previous SGA bear increased risks for subsequent infant mortality, which was greater among black mothers. Hence, SGA plays an important role in the black-white disparity in infant mortality. Women's previous childbearing experiences could serve as important criterion in determining appropriate interconception strategies to improve infant health and survival.

Preconceptional stress and racial disparities in preterm birth: an overview

OBJECTIVE

We reviewed the evidence for three theories of how preconceptional psychosocial stress could act as a contributing determinant of excess preterm birth risk among African American women: early life developmental plasticity and epigenetic programming of adult neuroendocrine systems; blunting, weathering, or dysfunction of neuroendocrine and immune function in response to chronic stress activation through the life course; individuals' adoption of risky behaviors such as smoking as a response to stressful stimuli.

METHODS

Basic science, clinical, and epidemiologic studies indexed in MEDLINE and Web of Science databases on preconceptional psychosocial stress, preterm birth and race were reviewed.

RESULTS

Mixed evidence leans towards modest associations between preconceptional chronic stress and preterm birth (for example common odds ratios of 1.2-1.4), particularly in African American women, but it is unclear whether this association is causal or explains a substantial portion of the Black-White racial disparity in preterm birth. The stress-preterm birth association may be mediated by hypothalamic-pituitary-adrenal axis dysfunction and susceptibility to bacterial vaginosis, although these mechanisms are incompletely understood. Evidence for the role of epigenetic or early life programming as a determinant of racial disparities in preterm birth risk is more circumstantial.

CONCLUSIONS

Preconceptional stress, directly or in interaction with host genetic susceptibility or infection, remains an important hypothesized risk factor for understanding and reducing racial disparities in preterm birth. Future studies that integrate adequately sized epidemiologic samples with measures of stress, infection, and gene expression, will advance our knowledge and allow development of targeted interventions.