Massachusetts Birth Research Articles

Neighborhood Child Opportunity and Preterm Birth Rates by Race and Ethnicity

In the US, infants born to non-Hispanic Black birthing parents are 50% more likely to be born preterm than those born to non-Hispanic White birthing parents, and individual-level factors do not fully account for this inequity. Neighborhood context, rooted in historic patterns of structural racism, may facilitate understanding patterns of inequity in preterm birth. To estimate the association between neighborhood opportunity level, measured by the Child Opportunity Index (COI), and preterm birth among infants in Massachusetts. In this cross-sectional, population-based study, Massachusetts birth certificates from 3 large metropolitan areas (Boston, Springfield, and Worcester) were linked to US Census tract-level data from the COI, and log binomial regression models and generalized estimating equations were fit to examine associations of different levels of opportunity with preterm birth. Singleton infants born in Massachusetts between February 1, 2011, and December 31, 2015, were included. Analyses were originally conducted in 2019 and updated in 2024. Level of child opportunity (measured by the COI) at the US Census tract level. Race and ethnicity were ascertained from the birth certificate, as reported by the birthing parent. Live birth before 37 completed weeks' gestation. The analytic dataset included 267 553 infants, of whom 18.9% were born to Hispanic, 10.1% to non-Hispanic Asian or Pacific Islander, 10.1% to non-Hispanic Black, and 61.0% to non-Hispanic White birthing parents. More than half of infants born to non-Hispanic Black and Hispanic birthing parents were born into very low opportunity neighborhoods, and in crude models, this was associated with greater prevalence of preterm birth relative to very high opportunity neighborhoods (prevalence ratio, 1.44; 95% CI, 1.37-1.52). After adjustment for covariates, infants born into very low opportunity neighborhoods still had a greater prevalence of preterm birth (prevalence ratio, 1.16; 95% CI, 1.10-1.23). In this cross-sectional study of neighborhood opportunity and preterm birth, elevated risk associated with exposure to a very low opportunity neighborhood, coupled with the disproportionate exposure by race and ethnicity, points to a modifiable factor that may contribute to racial and ethnic inequities in preterm birth. Future research should investigate interventions that seek to address neighborhood opportunity.

Expanding the Massachusetts Birth Defects Monitoring Program to include additional pregnancy outcomes: Programmatic efforts and impacts on case ascertainment, 2012-2020.

Birth defects affect 1 in 33 infants in the United States and are a leading cause of infant mortality. Birth defects surveillance is crucial for informing public health action. The Massachusetts Birth Defects Monitoring Program (MBDMP) began collecting other pregnancy losses (OPLs) in 2011, including miscarriages (<20 weeks gestation) or elective terminations (any gestational age), in addition to live births and stillbirths (≥20 weeks gestation). We describe programmatic changes for adding OPLs and their impact on prevalence estimates. Using population-based, statewide, data from the MBDMP (2012-2020), we assessed prevalence per 10,000 live births and 95% confidence intervals (CIs) with and without OPLs overall and for specific birth defects by time period, maternal age, and race/ethnicity. Including OPLs required amending a state statute and promulgating regulations, new data sources, and additional data processing, cleaning, and verification. Overall prevalence with OPLs increased from 257.4 (95% CI: 253.5-261.4) to 333.9 (95% CI: 329.4-338.4) per 10,000; increases were observed in all time periods, age, and race/ethnicity groups. After including OPLs, the prevalence increased for neural tube defects [3.2 (2.7-3.6) to 8.3 (7.6-9.0)], and trisomies 13 [0.5 (0.3-0.7) to 4.1 (3.6-4.6)], 18 [1.5 (1.2-1.9) to 8.2 (7.5-8.9)], and 21 [12.3 (11.4-13.2) to 28.9 (27.6-30.2)]. Cardiovascular defects increased slightly, while prevalence of eye/ear, respiratory, and gastrointestinal defects remained similar. Adding OPLs required substantial programmatic efforts and resulted in more complete case ascertainment, particularly for certain birth defects. More complete case ascertainment will allow for improved research, screening, and resource allocation.

Inequities in COVID-19 Vaccination Coverage Among Pregnant Persons, by Disaggregated Race and Ethnicity - Massachusetts, May 2021-October 2022.

National estimates suggest that COVID-19 vaccination coverage among pregnant persons is lower among those identifying as Hispanic or Latino (Hispanic) and non-Hispanic Black or African American. When examining COVID-19 vaccination coverage during pregnancy by race and ethnicity, however, data are typically limited to large, aggregate categories that might obscure within-group inequities. To address this, Massachusetts examined COVID-19 vaccination coverage among pregnant persons by combinations of 12 racial and 34 ethnic groupings. Among 102,275 persons with a live birth in Massachusetts during May 1, 2021-October 31, 2022, receipt of ≥1 dose of a COVID-19 vaccine before or during pregnancy was 41.6% overall and was highest among persons who identified as Asian (55.0%) and lowest among those who identified as Hispanic (26.7%). However, within all broad racial and ethnic groupings, disparities in COVID-19 vaccination coverage were identified when the data were disaggregated into more granular categories; for example, COVID-19 vaccination coverage ranged from 10.8%-61.1% among pregnant persons who identified as Hispanic. Disaggregated analyses reveal diverse experiences within broad racial and ethnic groupings. This information can be used to guide outreach to pregnant persons in communities with lower rates of COVID-19 vaccination coverage during pregnancy.

Experiences of Midwives Attending Home Births in Massachusetts During the COVID-19 Pandemic.

Public interest in home birth in the United States increased during the COVID-19 pandemic. Midwives attend the vast majority of home births and are experts in providing home birth care. However, limited data are available about the experiences of midwives attending home births during the pandemic in the United States. We developed a cross-sectional survey comprising 34 questions, which included 5 open-ended questions. The survey was distributed online in June 2021 to midwives attending home birth in Massachusetts. We calculated descriptive statistics for the quantitative survey responses and identified qualitative free-text responses illustrating the results. Eighteen midwives and 2 midwife apprentices responded to the survey, approximately 50% of Massachusetts' total number of midwives known to attend homebirths. The majority of the 20 respondents reported an increase in public interest in home birth (n = 17) and higher caseloads (n = 14) since the start of the pandemic. Respondents reported an increase in the number of clients transferring to their practices at a later gestational age (n = 13) and who identified as people of color (n = 8). They described both better and worse transfer of care to hospital experiences. Work-life balance and unpredictable income were the top 2 reported obstacles to home birth practice. The results of our study indicate that midwives providing home birth care in Massachusetts witnessed a surge in demand for their services during the pandemic. Implementing policies and practices that provide support for certified professional midwives could strengthen the home birth workforce, enhance access to home birth options, and optimize transfers to hospital settings when necessary.

Unmatched spatially stratified controls: A simulation study examining efficiency and precision using spatially-diverse controls and generalized additive models

Unmatched spatially stratified random sampling (SSRS) of non-cases selects geographically balanced controls by dividing the study area into spatial strata and randomly selecting controls from all non-cases within each stratum. The performance of SSRS control selection was evaluated in a case study spatial analysis of preterm birth in Massachusetts. In a simulation study, we fit generalized additive models using controls selected by SSRS or simple random sample (SRS) designs. We compared mean squared error (MSE), bias, relative efficiency (RE), and statistically significant map results to the model results with all non-cases. SSRS designs had lower average MSE (0.0042–0.0044) and higher RE (77–80%) compared to SRS designs (MSE: 0.0072–0.0073; RE across designs: 71%). SSRS map results were more consistent across simulations, reliably identifying statistically significant areas. SSRS designs improved efficiency by selecting controls that are geographically distributed, particularly from low population density areas, and may be more appropriate for spatial analyses.

SARS-CoV-2 infection during pregnancy and preterm birth in Massachusetts from March 2020 through March 2021.

SARS-CoV-2 infection during pregnancy has been linked to preterm birth, but this association is not well understood. To examine the association between SARS-CoV-2 infection and spontaneous and provider-initiated preterm birth (PTB), and how timing of infection, and race/ethnicity as a marker of structural inequality, may modify this association. We conducted a retrospective cohort study among pregnant people who delivered singleton, liveborn infants (22-44 weeks gestation) from 1 March 2020 to 31 March 2021 (n= 68,288). We used Cox proportional hazards models to compare the hazard of PTB between pregnant people with and without laboratory-confirmed SARS-CoV-2 infection during pregnancy. We evaluated this association according to the trimester of infection, timing from infection to birth, and timing of PTB. We also examined the joint associations of SARS-CoV-2 infection and race/ethnicity with PTB using the relative excess risk due to interaction (RERI). Positive SARS-CoV-2 tests were identified for 2195 pregnant people (3.2%). The prevalence of PTB was 7.2% (3.8% spontaneous, 3.6% provider-initiated). SARS-CoV-2 infection during pregnancy was associated with an increased risk of PTB overall (adjusted hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.34, 1.74), and provider-initiated PTB (HR 1.79, 95% CI 1.50, 2.12) but not spontaneous PTB (HR 1.09, 95% CI 0.89, 1.36). Second trimester infections were associated with an increased risk of provider-initiated PTB, and third trimester infections were associated with an increased risk of both PTB subtypes. A joint inverse association between White non-Hispanic race/ethnicity and SARS-CoV-2 infection and spontaneous PTB (HR 0.56, 95% CI 0.34, 0.94; RERI -0.6, 95% CI -1.0, -0.2) was also observed. SARS-CoV-2 infections were primarily associated with an increased risk for provider-initiated PTB in this study. These findings highlight the importance of promoting infection-prevention strategies among pregnant people.

Congenital Cytomegalovirus Screening in Massachusetts Birth Hospitals: A Statewide Survey.

This study sought to assess the current state of screening for congenital cytomegalovirus infection in newborns among birth hospitals and newborn nurseries in the state of Massachusetts. A survey assessing hospital protocols for cytomegalovirus testing in newborns was distributed to all birth hospitals and newborn nurseries in Massachusetts from November 2020 to February 2021. 73.3% of hospitals responded to at least one survey question. Of these, fewer than half (48.5%) had any established approach for neonatal cytomegalovirus screening. Salivary polymerase chain reaction was the most common testing modality. Most hospitals did not perform confirmatory testing for positive test results. Most respondents (87.9%) did not know or did not answer how results of cCMV screening were reported to families and who was responsible for coordinating care for cCMV-infected infants. We conclude that congenital cytomegalovirus screening protocols are absent or incomplete in most Massachusetts birth hospitals and newborn nurseries. A cohesive strategy involving standardized education and screening guidelines is needed to reduce the incidence and burden of congenital cytomegalovirus disease on children and their families.

Characteristics of People With and Without Laboratory-Confirmed SARS-CoV-2 Infection During Pregnancy, Massachusetts, March 2020-March 2021.

Objectives:Pregnant people infected with SARS-CoV-2, the virus that causes COVID-19, are at increased risk for severe illness and death compared with nonpregnant people. However, population-based information comparing characteristics of people with and without laboratory-confirmed SARS-CoV-2 infection during pregnancy is limited. We compared the characteristics of people with and without SARS-CoV-2 infection during pregnancy in Massachusetts.Methods:We compared maternal demographic characteristics, pre-pregnancy conditions, and pregnancy complications of people with and without SARS-CoV-2 infection during pregnancy with completed pregnancies resulting in a live birth in Massachusetts during March 1, 2020–March 31, 2021. We tested for significant differences in the distribution of characteristics of pregnant people by SARS-CoV-2 infection status overall and stratified by race and ethnicity. We used modified Poisson regression analyses to examine the association between race and ethnicity and SARS-CoV-2 infection during pregnancy.Results:Of 69 960 completed pregnancies identified during the study period, 3119 (4.5%) had laboratory-confirmed SARS-CoV-2 infection during pregnancy. Risk for SARS-CoV-2 infection was higher among Hispanic (adjusted risk ratio [aRR] = 2.3; 95% CI, 2.1-2.6) and non-Hispanic Black (aRR = 1.9; 95% CI, 1.7-2.1) pregnant people compared with non-Hispanic White pregnant people.Conclusions:This study demonstrates the disproportionate impact of SARS-CoV-2 infection on Hispanic and non-Hispanic Black pregnant people in Massachusetts, which may widen existent inequities in maternal morbidity and mortality. Future research is needed to elucidate the structural factors leading to these inequities.

Maternal exposure to black carbon and nitrogen dioxide during pregnancy and birth weight: Using machine-learning methods to achieve balance in inverse-probability weights

BackgroundLow birth weight is associated with increased risks of health problems in infancy and later life. Among the epidemiological analyses suggesting an association between air pollution and birth weight, few have estimated the effects of black carbon (BC) or together with nitrogen dioxide (NO2), and even fewer studies have used causal modelling. MethodsWe examined 1,119,011 birth records between 2001/01/01 and 2015/12/31 from the Massachusetts Birth Registry to investigate causal associations between prenatal exposure to BC and NO2 and birth weight. We calculated mean residential BC and NO2 exposures 0–30, and 31–280 days prior to birth from validated spatial-temporal models. We fit generalized propensity score models with gradient boosting tuned by a new algorithm to achieve covariate balance, then fit marginal structural models with stabilized inverse-probability weights. ResultsThroughout pregnancy, the average birth weight would drop by 17.0 g (95% CI: 15.4, 18.6) for an IQR increase of 0.14 μg/m3 in BC and would independently drop by 19.9 g (95% CI: 18.6, 21.3) for an IQR increase of 9.8 ppb in NO2. Most of the negative effects of BC on birth weight are from 0 to 30 days before the delivery date. The estimated odds ratio of low birth weight for every IQR increase during the entire pregnancy was 1.131 (95% CI: 1.106, 1.156) for BC and 1.082 (95% CI: 1.062, 1.103) for NO2. ConclusionsWe found that prenatal exposures to both BC and NO2 were associated with lower birth weight.

The effect of prenatal temperature and PM2.5 exposure on birthweight: weekly windows of exposure throughout the pregnancy

BACKGROUND AND AIM: Birthweight is a strong predictor of normal growth, healthy development, and survival. Several studies have found associations between temperature, fine particulate matter (PM2.5), and birth weight. However, the relevant timing of exposures varies between studies and is yet unclear. Therefore, we assessed the difference in term birthweight (TBW) associated with weekly exposure to temperature and PM2.5 throughout 37 weeks of gestation. METHODS: We included all singleton live term births in Massachusetts, U.S between 2004 and 2015 (n=712,438). Weekly PM2.5 and temperature predictions were estimated on a 1 km grid from satellite-based models. We utilized a distributed lag nonlinear model (DLNM) to estimate the difference in TBW associated with weekly exposures to PM2.5 and temperature simultaneously from the last menstrual period to 37 weeks of gestation. RESULTS:We found a nonlinear association with temperature exposure. We observed positive differences in TBW associated with rises of colder temperatures (2.6g increase, 95% CI 0.1g; 5.1g, for one ºC increase from -4 ºC) and negative difference in TBW associated with rises of warmer temperatures (7.9g decrease, 95% CI -11.2g; -4.6g, for one ºC increase from 23 ºC). Temperature effects were larger in the first and final weeks of gestation. We observed a negative difference in TBW associated with PM2.5 exposure. Overall, one µg/m3 increase in prenatal exposure was associated with 3.9g lower TBW (95% CI -5.0g; -2.9g). PM2.5 effects were larger in the final weeks of gestation. CONCLUSIONS:We found heat and PM2.5 exposure to be related to lower TBW. Our findings suggest that women are more susceptible to both exposures towards the end of pregnancy. Susceptibility to heat was higher in the initial weeks of pregnancy as well. These critical windows of susceptibility can be communicated to pregnant women during routine prenatal visits to increase awareness and target interventions to reduce exposures. KEYWORDS: birthweight, temperature, air pollution, birth outcomes

Maternal exposure to traffic-related pollutants during pregnancy and birth weight: using machine-learning methods to achieve balance in inverse-probability weights

BACKGROUND AND AIM: Low birth weight (LBW) is associated with increased risks of health problems in infancy and later life. Among the current epidemiological analyses suggesting the association between air pollution and birth weight, few have specifically estimated the effects of traffic-related pollutants or used causal modelling. We aimed to investigate the causal association between prenatal exposure to black carbon (BC) and nitrogen dioxide (NO₂) and birth weight using machine learning methods to achieve balance in inverse-probability weights. METHODS: We examined 1,119,011 birth records between January 1, 2001 and December 31, 2015 from the Massachusetts Birth Registry. Mean residential BC and NO₂ exposure 0-30, 31-90, 91-280 days prior to birth were calculated using estimates from validated spatial-temporal models. We fit generalized propensity score models with gradient boosting tuned by a new algorithm to achieve covariate balance, then fit marginal structural models with stabilized inverse-probability weights calculated from those models. RESULTS:Over the entire pregnancy, average birth weight would drop by -31.2 g (95% CI: -35.5, -26.9) for an IQR increase of 0.145 μg/m3 in BC and would drop by -25.9 g (95% CI: -30.1, -21.7) for an IQR increase of 9.8 ppb in NO₂. The effect sizes are similar in the three averaging periods for BC but the effect in the 91-280 prior period for NO₂ is larger than the other two exposure windows. The estimated odds ratio of LBW (defined as birth weight less than 2,500 g) for every IQR increase during the entire pregnancy was 1.21 (95% CI: 1.13, 1.28) for BC and was 1.11 (95% CI: 1.05, 1.18) for NO₂. CONCLUSIONS:In full-term singleton live births in Massachusetts between 2001 and 2015, higher maternal exposure to traffic-related air pollution (BC and NO₂) during pregnancy resulted in lowering birth weight and increasing the odds of LBW. KEYWORDS: Air pollution, Traffic-related, Big data, Birth outcomes, Causal inference, Epidemiology

The effect of prenatal temperature and PM2.5 exposure on birthweight: Weekly windows of exposure throughout the pregnancy

BackgroundBirthweight is a strong predictor of normal growth, healthy development, and survival. Several studies have found associations between temperature, fine particulate matter (PM2.5), and birth weight. However, the relevant timing of exposures varies between studies and is yet unclear. Therefore, we assessed the difference in term birthweight (TBW) associated with weekly exposure to temperature and PM2.5 throughout 37 weeks of gestation. MethodsWe included all singleton live term births in Massachusetts, U.S between 2004 and 2015 (n = 712,438). Weekly PM2.5 and temperature predictions were estimated on a 1 km grid from satellite-based models. We utilized a distributed lag nonlinear model (DLNM) to estimate the difference in TBW associated with weekly exposures from the last menstrual period to 37 weeks of gestation. ResultsWe found a nonlinear association with prenatal temperature exposure. Larger effects were observed in warmer temperatures, where higher temperatures were negatively associated with TBW. Temperature effects were larger in the first and final weeks of gestation. We observed a negative difference in TBW associated with PM2.5 exposure. Overall, a 1 µg/m3 increase in prenatal exposure was associated with 3.9 g lower TBW (95% CI −5.0 g; −2.9 g). PM2.5 effects were larger in the final weeks of gestation. ConclusionWe found heat and PM2.5 exposure to be related to lower TBW. Our findings suggest that women are more susceptible to both exposures towards the end of pregnancy. Susceptibility to heat was higher in the initial weeks of pregnancy as well. These critical windows of susceptibility can be communicated to pregnant women during routine prenatal visits to increase awareness and target interventions to reduce exposures.

Influence of Placental Abnormalities and Pregnancy-Induced Hypertension in Prematurity Associated with Various Assisted Reproductive Technology Techniques.

Objective. Assisted reproductive technology (ART)-treated women exhibit increased risk of premature delivery compared to fertile women. We evaluated whether ART treatment modalities increase prematurity and whether placental abnormalities and pregnancy-induced hypertensive (PIH) disorders mediate these risks. Method(s): This retrospective study of ART-treated and fertile deliveries (2004–2017) used an ART-cycle database linked to Massachusetts birth certificates and hospital discharges. Outcomes of late preterm birth (LPTB: 34–36 weeks gestation) and early preterm birth (EPTB: <34 weeks gestation) were compared with term deliveries (≥37 weeks gestation) in ART-treated (linked to the ART database) and fertile (no indicators of infertility or ART) deliveries. ART treatments with autologous oocyte, donor oocyte, fresh or frozen embryo transfer (FET), intracytoplasmic sperm injection (ICSI) and no-ICSI were separately compared to the fertile group. Adjusted odds ratios (AOR) were calculated with multivariable logistic regression: placental abnormalities or PIH were quantified in the pathway as mediators. Results: There were 218,320 deliveries: 204,438 fertile and 13,882 ART-treated. All treatment types increased prematurity (AOR 1.31–1.58, LPTB; AOR 1.34–1.48, EPTB). Placental abnormalities mediated in approximately 22% and 38% of the association with LPTB and EPTB, respectively. PIH mediated 25% and 33% of the association with LPTB and EPTB in FET and donor oocyte cycles, more than other treatments (<10% LPTB and <13% EPTB). Conclusions: ART-treatment and all ART modalities increased LPTB and EPTB when compared with fertile deliveries. Placental abnormalities modestly mediated associations approximately equally, while PIH was a stronger mediator in FET and donor oocyte cycles. Reasons for differences require exploration.

Residential radon exposure and hypertensive disorders of pregnancy in Massachusetts, USA: A cohort study

BackgroundExposure to ionizing radiation has been associated with hypertension, but the relationship between residential radon exposure and hypertensive disorders of pregnancy (HDP) has not been examined. MethodsWe used the Massachusetts Birth Registry of Vital Records from 2001 to 2015 including women with a singleton pregnancy without prior hypertension. The binary outcome (HDP) included gestational hypertension and pre-eclampsia cases and was assessed using birth certificate data. We obtained 141,665 basement radon measurements from Spruce Environmental Technologies, Inc. and modeled the monthly zip code basement radon level. We used a logistic regression model adjusted for sociodemographic covariates, maternal comorbidities, PM2.5, season, temperature, and relative humidity. We examined effect modification by maternal age, race, and maternal education as an indicator of socio-economic status. ResultsOf 975,528 women, 3.7% (36,530) of them developed HDP. Zip code level radon ranged from 22 to 333 mBq/m3. An interquartile range (IQR) increase in zip code radon level throughout pregnancy was associated with a 15% increase in the odds of HDP (95% CI 13% to 18%). In women less than 20 years old, an IQR increase in zip code level radon was associated with 38% increase in the odds of HDP (95% CI 24% to 50%), while the effect was smaller in older women. There was no effect modification by maternal race or education. ConclusionsIn this cohort, higher levels of residential radon are associated with increased odds of HDP. After stratifying by age, this effect was stronger in participants younger than 20 years old. Since the burden of hypertensive disorders of pregnancy is increasing and affects women’s future cardiovascular health, identification of modifiable risk factors is of great importance.

Higher levels of residential radon are associated with higher odds of PIH disorders in Massachusetts, USA

Background: Exposure to ionizing radiation has been associated with hypertension outside pregnancy, but the association between residential radon and pregnancy-induced hypertensive (PIH) disorders has not been evaluated. Methods: We used the Massachusetts Birth Registry of Vital Records from 2001-2015 to study women with a singleton pregnancy without prior hypertension. The PIH disorders status was obtained from the birth certificates as a binary variable. Median zip code level measurements were used to estimate radon exposure at the lowest livable level of each place under closed-house conditions. We used a mixed-effects model adjusted for sociodemographic covariates, maternal comorbidities, PM2.5, temperature, and relative humidity. We examined effect modification by maternal age in two categories at the cutoff of 35 years. Results: Of 990,364 women, 3.7% (37,027) of them developed gestational hypertension. Median zip code level ranged from 0.1 to 19.9 pCi/L. An interquartile range (IQR) increase in median zip code radon level throughout pregnancy was associated with a 3% increase in the odds of PIH disorders (95% CI 2% to 5%) in the full cohort. In women less than 35 years old, an IQR increase in medial residential zip code level, radon was associated with a 4.1% increase in the odds of PIH disorders (95% CI 3% to 6%), while in women more than 35 years old, the association was null. Conclusions: In this cohort, higher levels of residential radon are associated with increased odds of PIH disorders. After stratifying by age, this effect remained significant only in women less than 35 years old. Since the burden of pregnancy-induced hypertensive disorders is high and affects women’s future cardiovascular health, the identification of modifiable risk factors is of great importance.

Exposure to environmental contaminants and risk of pregnancy induced hypertension and gestational diabetes mellitus

Introduction: Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB), are ubiquitously found in the environment and resistant to degradation. POPs, along with persistent organochlorine pesticides including p,p'-dichlorodiphenyl dichloroethylene (DDE) and heavy metals have been associated with various pregnancy outcomes but results are inconsistent.Objective: We assessed the associations between prenatal exposures to organochlorines and heavy metals and the development of gestational diabetes mellitus (GDM) and pregnancy induced hypertension (PIH). Methods: We used existing exposure models to predict prenatal levels of PCBs (using the sum of 4 prevalent congeners), DDE, HCB, lead (Pb) and mercury (Hg) for all pregnant women living in southeast Massachusetts between 1993-1998 (n=10,270). Outcome and covariate data were obtained from Massachusetts birth records. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for GDM and PIH were estimated using multivariable logistic regression models. Results: Approximately 1.8% of women in this study population developed GDM and 1.9% of women developed PIH. PCBs, DDE and HCB were strongly associated with the development of GDM, while no associations were observed for Pb and Hg exposure. After adjusting for weight gain during pregnancy, smoking during pregnancy, parity, race, and socioeconomic factors, the effects of PCBs (OR: 1.56; 95% CI: 1.10-2.22) and DDE (OR: 2.84; 95% CI: 1.90-4.25) on GDM remained. However, the risk associated with HCB exposure was no longer significant after adjusting for confounders. Associations with PIH were null.Conclusions: These results suggest that women with high prenatal levels of PCBs and DDE may have a higher risk of developing GDM. We found no associations between PIH and exposures to organochlorines and heavy metals.

Prenatal exposure to particulate air pollution and gestational age at delivery in Massachusetts neonates 2001-2015: A perspective of causal modeling and health disparities.

Inverse probability weighting (IPW) quantile regression was applied to derive causal marginal population-level GA reduction for GA percentiles associated with increased ambient particulate matter with diameter <2.5 μm (PM2.5) levels at maternal residential address for each trimester and the month preceding delivery using Massachusetts birth registry 2001 to 2015. Stratified analyses were conducted for neonatal sex, maternal age/race/education, and extreme ambient temperature conditions. For neonates at 2.5th, 10th, 25th, 50th, 75th, and 97.5th percentiles of GA at delivery, we estimated an adjusted GA reduction of 4.2 days (95% confidence interval [CI] = 3.4, 5.0), 1.9 days (1.6, 2.1), 1.2 days (1.0, 1.4), 0.82 days (0.72, 0.92), 0.74 days (0.54, 0.94), and 0.54 days (0.15, 0.93) for each 5 μg/m3 increment in third trimester average PM2.5 levels. Final gestational month average exposure yielded a similar effect with greater magnitude. Male neonates and neonates of younger (younger than 35 years) and African American mothers as well as with high/low extreme temperature exposure in third trimester were more affected. Estimates were consistently higher at lower GA percentiles, indicating preterm/early-term births being more affected. Low-exposure analyses yielded similar results, restricting to areas with PM2.5 levels under US ambient annual standard of 12 μg/m3. Prenatal exposure to PM2.5 in late pregnancy reduced GA at delivery among Massachusetts neonates, especially among preterm/early-term births, male neonates, and neonates of younger and African American mothers. Exposure to extremely high/low temperature amplifies the effect of PM2.5 on GA.

Contributions to prematurity of maternal health conditions, subfertility, and assisted reproductive technology

To determine the maternal demographic, health, and fertility variables underlying prematurity. Retrospective: Society for Assisted Reproductive Technology Clinic Outcome Reporting System data linked to Massachusetts birth certificates and hospital stays. Not applicable. We included 166,963 privately insured, singleton, first births to women ≥18 years of age between 2004 and 2013. Deliveries were as follows: assisted reproductive technology (ART) when linked to Society for Assisted Reproductive Technology Clinic Outcome Reporting System, medically assisted reproduction (MAR) when fertility treatment was indicated on the birth certificate, unassisted subfertile (USF) when there were indications of subfertility but no treatment, and fertile if none of the above. None. Late preterm birth (LPTB; 34-36 weeks) and early preterm birth (EPTB; <34 weeks) were compared with term deliveries (≥37 weeks). Covariates that statistically significantly influenced prematurity in binary analysis were modeled by using multinomial logistic regression. Backward elimination and mediation analysis were used to determine the influence of single parameters on outcomes of others. LPTB was increased in the USF (adjusted odds ratio [AOR] 1.32, 95% confidence interval [CI] 1.06-1.65) and ART (AOR 1.42, 95% CI 1.30-1.56) but not MAR (AOR 1.16, 95% CI 0.98-1.37). ETPB was increased in all (USF: AOR 1.67, 95% CI 1.21-2.31; MAR: AOR 1.67, 95% CI 1.31-2.12; ART: AOR 1.40, 95% CI 1.21-1.61). The strongest effectors of prematurity were placental problems (LPTB: AOR 4.02; EPTB: AOR 10.28), pregnancy hypertension (LPTB: AOR 2.14; EPTB: AOR 2.88), and chronic hypertension (LPTB: AOR 1.85; EPTB: AOR 2.79). Mediation analysis demonstrated a statistically significant indirect effect of placental problems for ART and subfertility. The greatest effectors of prematurity were placental problems and hypertensive disorders. ART and, to a lesser extent, subfertility were both associated with preterm birth directly and indirectly mediated by placenta problems.

Pregnancy, Birth, and Infant Outcomes Among Women Who Are Deaf or Hard of Hearing

Being deaf or hard of hearing can be marginalizing and associated with inequitable health outcomes. Until recently, there were no U.S. population-based studies of pregnancy outcomes among deaf or hard of hearing women. In light of inconsistent findings in the limited available literature, this study sought to conduct a more rigorous study using population-based, longitudinal linked data to compare pregnancy complications, birth characteristics, and neonatal outcomes between deaf or hard of hearing and non-deaf or hard of hearing women. Researchers conducted a retrospective cohort study in 2019 using the Massachusetts Pregnancy to Early Life Longitudinal data system. This system links all Massachusetts birth certificates, fetal death reports, and delivery- and nondelivery-related hospital discharge records for all infants and their mothers. The study included women with singleton deliveries who gave birth in Massachusetts between January 1998 and December 2013. The deaf or hard of hearing women had an increased risk of chronic medical conditions and pregnancy complications including pre-existing diabetes, gestational diabetes, pre-eclampsia and eclampsia, and placental abruption. Deliveries to deaf or hard of hearing women were significantly associated with adverse birth outcomes, including preterm birth, low birth weight or very low weight, and low 1-minute Apgar score or low 5-minute Apgar score. No significant differences were found in size for gestational age, fetal distress, or stillbirth among deaf or hard of hearing women. Findings from this 2019 study indicate that deaf or hard of hearing women are at a heightened risk for chronic conditions, pregnancy-related complications, and adverse birth outcomes and underscore the need for systematic investigation of the pregnancy- and neonatal-related risks, complications, costs, mechanisms, and outcomes of deaf or hard of hearing women.

Contributions to prematurity of maternal health conditions, subfertility, and assisted reproductive technology (ART)

Previous studies show subfertility and ART to increase rates of prematurity. Our goal was to evaluate health conditions that underlie prematurity and assess whether subfertility/ART influence these. Retrospective cohort Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) deliveries were linked to Massachusetts birth certificates and hospital stays to identify privately insured singleton first births to women ≥ 18 years of age between 2004-2013. Deliveries were classified as ART when they linked to SART CORS, medically assisted reproduction (MAR) when fertility treatment was indicated on the birth certificate, unassisted subfertile (USF) when they had infertility diagnosis in prior hospital records or treatment for fertility in a prior delivery, and fertile if in none of the above groups. Late preterm birth (LPTB: 34-36 weeks) and early preterm birth (EPTB: <34 weeks) deliveries were compared to term deliveries (≥37 weeks). Covariates that significantly influenced the outcome of prematurity in a binary analysis (mother’s age race/ethnicity, education, chronic diabetes and hypertension, prior uterine surgery, thyroid disease, ectopic pregnancy, leiomyoma, bleeding/menstrual disorders, electrolyte imbalance, psychological disorders, overweight/obesity, prior hospitalizations, gravidity, gestational diabetes, pregnancy hypertension, placental problems, bleeding, and father’s age, race and education) were modeled using multinomial logistic regression. There were 155,997 term, 8,210 LPTB, and 2,756 EPTB deliveries. When adjusted for all covariates and compared with fertile, LPTB was increased in the USF (adjusted odds ratio [AOR] 1.32, 95% confidence interval [CI] 1.06-1.65) and ART (AOR 1.43, 95% CI 1,31-1,56) but not MAR (AOR 1.16, 95%CI 0.98-1.67) groups and ETPB was increased in all (AOR 1.67, 95% CI 1.21-2.31, USF; AOR 1.67, 95% CI 1.31-2.12 CI, MAR; AOR 1.40, 95% CI 1.22-1.62, ART). The four strongest effectors of prematurity when adjusted for all parameters were placental problems (AOR 4.01 LPTB; AOR 10.25 EPTB) pregnancy hypertension (AOR 2.14 LPTB; AOR 2.88 EPTB), chronic hypertension (AOR 1.85 LPTB; AOR 2.78 EPTB), and chronic diabetes (AOR 1.71 LPTB; AOR 2.01 EPTB) (P<0.001 for all). Removing subfertility/ART from the models did not change the AOR of any parameter. Removing placental problems increased LPTB (AOR 1.53) in the ART group and EPTB in UF (AOR 1.79), MAR (AOR 1.71) and ART (AOR 1.67) groups. Although subfertility/ART increased LPTB and EPTB they did not alter the effect of other parameters. However, placental problems appear to be on the pathway to LPTB and EPTB for subfertile/ART deliveries.