•Bisphenols and phthalate metabolites may be associated with altered fetal growth.•Associations were greatest among small and large fetuses and varied by sex.•Associations were strongest for ...replacement DEHP phthalates (DiNP and DnOP).•Effects of exposure on fetal growth may occur by the second trimester.
Bisphenols and phthalates are high production volume chemicals used as additives in a variety of plastic consumer products leading to near ubiquitous human exposure. These chemicals have established endocrine disrupting properties and have been linked to a range of adverse reproductive and developmental outcomes. Here, we investigated exposure in relation to fetal growth.
Participants included 855 mother-fetal pairs enrolled in the population-based New York University Children’s Health and Environment Study (NYU CHES). Bisphenols and phthalates were measured in maternal urine collected repeatedly during pregnancy. Analyses included 15 phthalate metabolites and 2 bisphenols that were detected in 50 % of participants or more. Fetal biometry data were extracted from electronic ultrasonography records and estimated fetal weight (EFW) was predicted for all fetuses at 20, 30, and 36 weeks gestation. We used quantile regression adjusted for covariates to model exposure-outcome relations across percentiles of fetal weight at each gestational timepoint. We examined sex differences using stratified models.
Few statistically significant associations were observed across chemicals, gestational time periods, percentiles, and sexes. However, within gestational timepoints, we found that among females, the molar sums of the phthalates DiNP and DnOP were generally associated with decreases in EFW among smaller babies and increases in EFW among larger babies. Among males, the opposite trend was observed. However, confidence intervals were generally wide at the tails of the distribution.
In this sample, exposure to bisphenols and phthalates was associated with small sex-specific shifts in fetal growth; however, few associations were observed at the median of fetal weight and confidence intervals in the tails were wide. Findings were strongest for DiNP and DnOP, which are increasingly used as replacements for DEHP, supporting the need for future research on these contaminants.
Abstract
STUDY QUESTION
How did the first two coronavirus disease 2019 (COVID-19) waves affect fertility rates in the USA?
SUMMARY ANSWER
States differed widely in how their fertility rates changed ...following the COVID-19 outbreak and these changes were influenced more by state-level economic, racial, political, and social factors than by COVID-19 wave severity.
WHAT IS KNOWN ALREADY
The outbreak of the COVID-19 pandemic contributed to already declining fertility rates in the USA, but not equally across states. Identifying drivers of differential changes in fertility rates can help explain variations in demographic shifts across states in the USA and motivate policies that support families in general, not only during crises.
STUDY DESIGN, SIZE, DURATION
This is an ecological study using state-level data from 50 US states and the District of Columbia (n = 51). The study period extends from 2020 to 2021 with historical data from 2016 to 2019. We identified Wave 1 as the first apex for each state after February 2020 and Wave 2 as the second apex, during Fall/Winter 2020–2021.
PARTICIPANTS/MATERIALS, SETTING, METHODS
State-level COVID-19 wave severity, defined as case acceleration during each 3-month COVID-19 wave (cases/100 000 population/month), was derived from 7-day weekly moving average COVID-19 case rates from the US Centers for Disease Control and Prevention (CDC). State-level fertility rate changes (change in average monthly fertility rate/100 000 women of reproductive age (WRA)/year) were derived from the CDC Bureau of Vital Statistics and from 2020 US Census and University of Virginia 2021 population estimates 9 months after each COVID-19 wave. We performed univariate analyses to describe national and state-level fertility rate changes following each wave, and simple and multivariable linear regression analyses to assess the relation of COVID-19 wave severity and other state-level characteristics with fertility rate changes.
MAIN RESULTS AND THE ROLE OF CHANCE
Nationwide, fertility dropped by 17.5 births/month/100 000 WRA/year following Wave 1 and 9.2 births/month/100 000 WRA/year following Wave 2. The declines following Wave 1 were largest among majority-Democrat, more non-White states where people practiced greater social distancing. Greater COVID-19 wave severity was associated with steeper fertility rate decline post-Wave 1 in simple regression, but the association was attenuated when adjusted for other covariates. Adjusting for the economic impact of the pandemic (hypothesized mediator) also attenuated the effect. There was no relation between COVID-19 wave severity and fertility rate change following Wave 2.
LIMITATIONS, REASONS FOR CAUTION
Our study harnesses state-level data so individual-level conclusions cannot be inferred. There may be residual confounding in our multivariable regression and we were underpowered to detect some effects.
WIDER IMPLICATIONS OF THE FINDINGS
The COVID-19 pandemic initially impacted the national fertility rate but, overall, the fertility rate rebounded to the pre-pandemic level following Wave 2. Consistent with prior literature, COVID-19 wave severity did not appear to predict fertility rate change. Economic, racial, political, and social factors influenced state-specific fertility rates during the pandemic more than the severity of the outbreak alone. Future studies in other countries should also consider whether these factors account for internal heterogeneity when examining the impact of the COVID-19 pandemic and other crises on fertility.
STUDY FUNDING/COMPETING INTEREST(S)
L.G.K. received funding from the National Institute of Environmental Health Sciences (R00ES030403), M.C. from the National Science Foundation Graduate Research Fellowship Program (20-A0-00-1005789), and M.L. and E.S. from the National Institute of Environmental Health Sciences (R01ES032808). None of the authors have competing interests.
TRIAL REGISTRATION NUMBER
N/A.
Phthalate exposure may contribute to hypertensive disorders of pregnancy (HDP), including preeclampsia/eclampsia (PE/E), but epidemiologic studies are lacking.
To evaluate associations of pregnancy ...phthalate exposure with development of PE/E and HDP.
Using data from 3,430 participants in eight Environmental influences on Child Health Outcomes (ECHO) Program cohorts (enrolled from 1999 to 2019), we quantified concentrations of 13 phthalate metabolites (8 measured in all cohorts, 13 in a subset of four cohorts) in urine samples collected at least once during pregnancy. We operationalized outcomes as PE/E and composite HDP (PE/E and/or gestational hypertension). After correcting phthalate metabolite concentrations for urinary dilution, we evaluated covariate-adjusted associations of individual phthalates with odds of PE/E or composite HDP via generalized estimating equations, and the phthalate mixture via quantile-based g-computation. We also explored effect measure modification by fetal sex using stratified models. Effect estimates are reported as odds ratios (OR) with 95% confidence intervals (95% CIs).
In adjusted analyses, a doubling of mono-benzyl phthalate (MBzP) and of mono (3-carboxypropyl) phthalate (MCPP) concentrations was associated with higher odds of PE/E as well as composite HDP, with somewhat larger associations for PE/E. For example, a doubling of MCPP was associated with 1.12 times the odds of PE/E (95%CI 1.00, 1.24) and 1.02 times the odds of composite HDP (95%CI 1.00, 1.05). A quartile increase in the phthalate mixture was associated with 1.27 times the odds of PE/E (95%CI 0.94, 1.70). A doubling of mono-carboxy isononyl phthalate (MCiNP) and of mono-carboxy isooctyl phthalate (MCiOP) concentrations were associated with 1.08 (95%CI 1.00, 1.17) and 1.11 (95%CI 1.03, 1.19) times the odds of PE/E. Effect estimates for PE/E were generally larger among pregnancies carrying female fetuses.
In this study, multiple phthalates were associated with higher odds of PE/E and HDP. Estimates were precise and some were low in magnitude. Interventions to reduce phthalate exposures during pregnancy may help mitigate risk of these conditions.
Pregnant women are widely exposed to organophosphate (OP) pesticides, which are potentially neurotoxicant for the developing fetus. We aimed to identify principal demographic and dietary predictors ...of OP pesticide exposure among 450 pregnant women participating in the New York University Children’s Health and Environment Study (enrolled 2016–19). Urinary concentrations of six dialkyl phosphate (DAP) metabolites (3 dimethyl (DM) metabolites and 3 diethyl (DE) metabolites) of OP pesticides were determined at three time points across pregnancy. At mid-gestation, the Diet History Questionnaire II was used to assess women’s dietary intake over the past year. Demographic characteristics were obtained using questionnaires and/or electronic health records. We used linear mixed models to evaluate the associations of demographic and food groups with DAP metabolite levels, and partial-linear single-index (PLSI) models to analyze the contribution proportions of food groups to DAP metabolite concentrations and the dose-response relationships between them. We observed that pregnant women in NYC had lower levels of OP pesticide metabolites than pregnant populations in Europe, Asia, and other regions in the U.S. Having lower pre-pregnancy body mass index and being Asian, employed, and single were associated with higher DAP metabolite concentrations. Fruit and grain intakes were associated with higher ∑DM, ∑DE, and ∑DAP levels. ∑DE concentrations increased 9.0% (95% confidence interval (CI) = 1.2%, 17.4%) per two-fold increase in dairy consumption, whereas ∑DE concentrations decreased 1.8% (95%CI = −3.1%, −0.4%) per two-fold increase in seafood consumption. The PLSI model indicated that among the food mixture, fruit and grains were the main food groups contributed to higher levels of ∑DAP, while meat contributed to lower levels of ∑DAP. The contribution proportions of fruit, grains, and meat were 18.7%, 17.9%, and 39.3%, respectively. Our results suggest that fruit, grains, and meat are major dietary components associated with OP pesticide exposure in urban pregnant women.
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•Organophosphate pesticides (OP) were repeatedly assessed in pregnant women in NYC.•Pregnant women had lower OP levels than comparable groups in Europe and Asia.•Lower BMI and being Asian, employed, and single were related to higher OP.•Fruit, grains, and meat were major food groups associated with OP exposure.
Main findings: Pregnant women in New York City had lower OP pesticide levels than those in Europe and Asia. Fruit, grains, and meat were major food groups contributing to OP pesticide exposure.
Phthalates are endocrine-disrupting chemicals with anti-androgenic qualities and studies reported associations between prenatal phthalate exposure and infant genitalia. This study investigated ...whether increased prenatal phthalate exposure is associated with decreased fetal penile measures.
Data was from the New York University Children's Health and Environment Study (2016-2019). Maternal urinary concentrations of 16 phthalate metabolites were quantified at <18 weeks gestation as a proxy for fetal exposure (n = 334 male pregnancies). We retrospectively measured penile length and width using ultrasounds conducted 18-24 weeks gestation (n = 173 fetuses). Associations of maternal urinary levels of phthalates with fetal penile length and width were determined using linear regression models.
57.2% of women were Hispanic, 31.8% Non-Hispanic White, 6.4% Asian, 2.3% Non-Hispanic Black, and 2.3% multiple races. Mean maternal age was 32 years (standard deviation SD = 5.7). Mean penile length was 7.13 mm (SD = 1.47) and width was 6.16 mm (SD = 0.87). An inverse relationship was observed between maternal levels of mono-ethyl phthalate and fetal penile length, and mono-(7-carboxy-n-heptyl) phthalate and penile width, though estimates were small and not significant when considering correction for multiple comparisons.
In our cohort we found no clinically meaningful associations between early pregnancy phthalate exposure and fetal penile length or width.
First-trimester phthalate metabolites were assessed in pregnant women in New York City. Penile length and width were retrospectively measured on clinically assessed ultrasounds conducted ≥18 weeks and <24 weeks of gestation. In this cohort, no clinically meaningful associations were observed between first-trimester prenatal phthalate exposure and fetal penile length. This study contributes to the limited but growing research on the impact of prenatal phthalate exposure on male fetal genital development. The results emphasize that there may not be a clear association between prenatal phthalate exposure and fetal penile length and width, and further research on this topic may be required.
Previous studies have provided data on determinants of phthalates in pregnant women, but results were disparate across regions. We aimed to identify the food groups and demographic factors that ...predict phthalate exposure in an urban contemporary pregnancy cohort in the US. The study included 450 pregnant women from the New York University Children's Health and Environment Study in New York City. Urinary concentrations of 22 phthalate metabolites, including metabolites of di-2-ethylhexylphthalate (DEHP), were determined at three time points across pregnancy by liquid chromatography coupled with tandem mass spectrometry. The Diet History Questionnaire II was completed by pregnant women at mid-pregnancy to assess dietary information. Linear mixed models were fitted to examine determinants of urinary phthalate metabolite concentrations. Using partial-linear single-index (PLSI) models, we assessed the major contributors, among ten food groups, to phthalate exposure. Metabolites of DEHP and its ortho-phthalate replacement, diisononyl phthalate (DiNP), were found in >90% of the samples. The sum of creatinine-adjusted DiNP metabolite concentrations was higher in older and single women and in samples collected in summer. Hispanic and non-Hispanic Black women had lower urinary concentrations of summed metabolites of di-n-octyl phthalate (DnOP), but higher concentrations of low molecular weight phthalates compared with non-Hispanic White women. Each doubling of grain products consumed was associated with a 20.9% increase in ∑DiNP concentrations (95%CI: 4.5, 39.9). PLSI models revealed that intake of dried beans and peas was the main dietary factor contributing to urinary ∑DEHP, ∑DiNP, and ∑DnOP levels, with contribution proportions of 76.3%, 35.8%, and 27.4%, respectively. Urinary metabolite levels of phthalates in pregnant women in NYC varied by age, marital status, seasonality, race/ethnicity, and diet. These results lend insight into the major determinants of phthalates levels, and may be used to identify exposure sources and guide interventions to reduce exposures in susceptible populations.
•Phthalate metabolites were repeatedly assessed in pregnant women in New York City.•Being older, single, and sampling in summer were related to higher DEHP metabolite levels.•Non-Hispanic Black women had higher levels of low molecular weight phthalates.•Beans and peas were dietary determinants of high molecular weight phthalates.•Beans and peas intake had a U-shaped relationship with DEHP metabolite levels.
Fetal exposure to environmental chemicals has been associated with adverse health outcomes in children and later into adulthood. While several studies have examined correlations and variability of ...non-persistent chemical exposures throughout pregnancy, many do not capture more recent exposures, particularly in New York City. Our goal was to characterize exposure to phthalates, bisphenols, polycyclic aromatic hydrocarbons, and organophosphate pesticides among pregnant women residing in New York City who enrolled in the New York University Children's Health and Environment Study (NYU CHES) between 2016 and 2018. We measured urinary chemical metabolite concentrations in 671 women at early, mid, and late pregnancy (median 10.8, 20.8, and 29.3 weeks, respectively). We calculated Spearman correlation coefficients among chemical concentrations at each measurement time point. We compared changes in population-level urinary metabolites at each stage using paired Wilcoxon signed-rank tests and calculated intraclass correlation coefficients (ICCs) to quantify intra-individual variability of metabolites across pregnancy. Geometric means and ICCs were compared to nine other pregnancy cohorts that recruited women in 2011 or later as well as nationally reported levels from women of child-bearing age. Compared with existing cohorts, women in NYU CHES had higher geometric means of organophosphate pesticides (Σdiethylphosphates = 28.7 nmol/g cr, Σdimethylphosphates = 57.3 nmol/g cr, Σdialkyl phosphates = 95.9 nmol/g cr), bisphenol S (0.56 μg/g cr), and 2-naphthalene (8.98 μg/g cr). Five PAH metabolites and two phthalate metabolites increased between early to mid and early to late pregnancy at the population level. Spearman correlation coefficients for chemical metabolites were generally below 0.50. Intra-individual exposures varied over time, as indicated by low ICCs (0.22–0.88, median = 0.38). However, these ICCs were often higher than those observed in other pregnancy cohorts. These results provide a general overview of the chemical metabolites measured in NYU CHES in comparison to other contemporary pregnancy cohorts and highlight directions for future studies.
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•671 pregnant women provided urine samples at early, mid, and late pregnancy.•BPS, 2-NAP, and OP pesticide metabolites had higher concentrations than other cohorts.•Five PAH metabolites and two phthalate metabolites increased over pregnancy.•ICCs were generally similar or higher to comparable pregnancy cohorts.
Objective
Both psychosocial stress and gestational weight gain are independently associated with adverse maternal and fetal outcomes. Studies of the association between psychosocial stress and ...gestational weight gain (GWG) have yielded mixed results. The objective of this study was to evaluate the association between psychosocial stress and GWG in a large population-based cohort.
Methods
Data from the nationally representative Pregnancy Risk Assessment Monitoring System (PRAMS) Phase 7 questionnaire 2012–2015 was utilized. Maternal psychosocial stress was assessed through response to questions designed to examine four domains of psychosocial stress (i.e., traumatic, financial, emotional, partner-related) three months prior to or during pregnancy. GWG was categorized using pre-pregnancy BMI and total GWG into inadequate, adequate, or excessive according to the Institute of Medicine’s GWG guidelines. Multinomial logistic regression was used to evaluate the association between psychosocial stressors and adequacy of GWG. Analyses took into account complex survey design.
Results
All respondents who delivered ≥ 37 weeks gestation with GWG information available were included in the analysis (
n
= 119,183). After adjusting for confounders, patients who reported financial stress were more likely to experience excessive versus adequate GWG (RRR 1.09 95%CI: 1.02–1.17). Exposure to any of the stressor groups did not significantly increase the risk of inadequate GWG.
Conclusions
This large, population-based study revealed that among pregnant people in the US, exposure to financial stress is associated with higher risk of excessive GWG. Understanding the role stress plays in GWG will help to inform initiatives targeting this important aspect of prenatal care.
Significance
What is already known on this subject?
Excessive gestational weight gain (GWG) has been linked to postpartum weight retention and long-term adverse maternal and child health outcomes. Multiple studies have shown an association between psychosocial stress and adverse fetal outcomes. Risks of inadequate weight gain include low birthweight and failure to initiate breast-feeding whereas the risks of excessive weight gain include cesarean deliveries and postpartum weight retention for the mother and large-for-gestational-age infants, macrosomia, and childhood overweight or obesity for the offspring.
What this study adds?
The 2012–2015 Pregnancy Risk Assessment Monitoring System (PRAMS) provides unique nationally representative data in which birth outcomes and maternal weight are linked to psychosocial stressors. Our study is the largest of its kind examining the link between stress and GWG and reveals that exposure to financial stress is associated with higher risk of excessive GWG in the US.
Abstract
While racial/ethnic differences in fetal growth have been documented, few studies have examined whether they vary by exogenous factors, which could elucidate underlying causes. The purpose ...of this study was to characterize longitudinal fetal growth patterns by maternal sociodemographic, behavioral, and clinical factors and examine whether associations with maternal race/ethnicity varied by these other predictors. Between 2016 and 2019, pregnant women receiving prenatal care at NYU Langone Health (New York, New York) were invited to participate in a birth cohort study. Women completed questionnaires, and clinical data were abstracted from ultrasound examinations. Maternal characteristics were assessed in relation to fetal biometric measures throughout pregnancy using linear mixed models. Maternal race/ethnicity was consistently associated with fetal biometry: Black, Hispanic, and Asian women had fetuses with smaller head circumference, abdominal circumference, and biparietal diameter than White women. The associations between race/ethnicity and fetal growth varied by nativity for Asian women, such that the disparity between Asian and White women was much greater for US-born women than for foreign-born women. However, associations for Black and Hispanic women did not vary by nativity. While race/ethnicity-specific fetal growth standards have been proposed, additional work is needed to elucidate what could be driving these differences, including factors that occur in parallel and differentially affect fetal growth.