Black-white differences in chronic stress exposures to predict preterm birth: interpretable, race/ethnicity-specific machine learning model.

BACKGROUND: Differential exposure to chronic stressors by race/ethnicity may help explain Black-White inequalities in rates of preterm birth. However, researchers have not investigated the cumulative, interactive, and population-specific nature of chronic stressor exposures and their possible nonlinear associations with preterm birth. Models capable of computing such high-dimensional associations that could differ by race/ethnicity are needed. We developed machine learning models of chronic stressors to both predict preterm birth more accurately and identify chronic stressors and other risk factors driving preterm birth risk among non-Hispanic Black and non-Hispanic White pregnant women. METHODS: Multivariate Adaptive Regression Splines (MARS) models were developed for preterm birth prediction for non-Hispanic Black, non-Hispanic White, and combined study samples derived from the CDC's Pregnancy Risk Assessment Monitoring System data (2012-2017). For each sample population, MARS models were trained and tested using 5-fold cross-validation. For each population, the Area Under the ROC Curve (AUC) was used to evaluate model performance, and variable importance for preterm birth prediction was computed. RESULTS: Among 81,892 non-Hispanic Black and 277,963 non-Hispanic White live births (weighted sample), the best-performing MARS models showed high accuracy (AUC: 0.754-0.765) and similar-or-better performance for race/ethnicity-specific models compared to the combined model. The number of prenatal care visits, premature rupture of membrane, and medical conditions were more important than other variables in predicting preterm birth across the populations. Chronic stressors (e.g., low maternal education and intimate partner violence) and their correlates predicted preterm birth only for non-Hispanic Black women. CONCLUSIONS: Our study findings reinforce that such mid or upstream determinants of health as chronic stressors should be targeted to reduce excess preterm birth risk among non-Hispanic Black women and ultimately narrow the persistent Black-White gap in preterm birth in the U.S.

Investigating the Black Birth Experience: A Race-Stratified Analysis of Preterm Birth Risk and Exposure to Metropolitan Statistical Area-Level Police-Related Deaths, US 2018-2019.

Police-related violence may be a source of chronic stress underlying entrenched racial inequities in reproductive health in the USA. Using publicly available data on police-related fatalities, we estimated total and victim race-specific rates of police-related fatalities (deaths per 100,000 population) in 2018-2019 for Metropolitan Statistical Areas (MSA) and counties within MSAs in the USA. Rates were linked to data on live births by maternal MSA and county of residence. We fit adjusted log-Poisson models with generalized estimating equations and cluster-robust standard errors to estimate the relative risk of preterm birth associated with the middle and highest tertiles of police-related fatalities compared to the lowest tertile. We included a test for heterogeneity by maternal race/ethnicity and additionally fit race/ethnicity-stratified models for associations with victim race/ethnicity-specific police-related fatality rates. Fully adjusted models indicated significant adverse associations between police-related fatality rates and relative risk of preterm birth for the total population, non-Hispanic Black, and non-Hispanic White groups separately. Results confirm the role of fatal police violence as a social determinant of population health outcomes and inequities, including preterm birth.

Addressing bias in preterm birth research: The role of advanced imputation techniques for missing race and ethnicity in perinatal health data.

OBJECTIVES: To evaluate the effectiveness of Bayesian Improved Surname Geocoding (BISG) and Bayesian Improved First Name Surname Geocoding (BIFSG) in estimating race and ethnicity, and how they influence odds ratios for preterm birth. METHODS: We analyzed hospital birth admission electronic health records (EHR) data (N = 9985). We created two simulation sets with 40 % of race and ethnicity data missing randomly or more likely for non-Hispanic black birthing people who had preterm birth. We calculated C-statistics to evaluate how accurately BISG and BIFSG estimate race and ethnicity. We examined the association between race and ethnicity and preterm birth using logistic regression and reported odds ratios (OR). RESULTS: BISG and BIFSG showed high accuracy for most racial and ethnic categories (C-statistics = 0.94-0.97, 95 % confidence intervals [CI] = 0.92-0.97). When race and ethnicity were not missing at random, BISG (OR = 1.25, CI = 0.97-1.62) and BIFSG (OR = 1.38, CI = 1.08-1.76) resulted in positive estimates mirroring the true association (OR = 1.68, CI = 1.34-2.09) for Non-Hispanic Black birthing people, while traditional methods showed contrasting estimates (Complete case OR = 0.62, CI = 0.41-0.94; multiple imputation OR = 0.63, CI = 0.40-0.98). CONCLUSIONS: BISG and BIFSG accurately estimate missing race and ethnicity in perinatal EHR data, decreasing bias in preterm birth research, and are recommended over traditional methods to reduce potential bias.

The interrelation between microbial immunoglobulin coating, vaginal microbiota, ethnicity, and preterm birth.

BACKGROUND: Vaginal microbiota composition is associated with spontaneous preterm birth (sPTB), depending on ethnicity. Host-microbiota interactions are thought to play an important underlying role in this association between ethnicity, vaginal microbiota and sPTB. METHODS: In a prospective cohort of nulliparous pregnant women, we assessed vaginal microbiota composition, vaginal immunoglobulins (Igs), and local inflammatory markers. We performed a nested case-control study with 19 sPTB cases, matched based on ethnicity and midwifery practice to 19 term controls. RESULTS: Of the 294 included participants, 23 pregnancies ended in sPTB. We demonstrated that Lactobacillus iners-dominated microbiota, diverse microbiota, and ethnicity were all independently associated with sPTB. Microbial Ig coating was associated with both microbiota composition and ethnicity, but a direct association with sPTB was lacking. Microbial IgA and IgG coating were lowest in diverse microbiota, especially in women of any ethnic minority. When correcting for microbiota composition, increased microbial Ig coating correlated with increased inflammation. CONCLUSION: In these nulliparous pregnant women, vaginal microbiota composition is strongly associated with sPTB. Our results support that vaginal mucosal Igs might play a pivotal role in microbiota composition, microbiota-related inflammation, and vaginal community disparity within and between ethnicities. This study provides insight in host-microbe interaction, suggesting that vaginal mucosal Igs play an immunomodulatory role similar to that in the intestinal tract. Video Abstract.

Risk of Adverse Perinatal Outcomes Among African-born Black Women in California, 2011-2020.

BACKGROUND: African-born women have a lower risk of preterm birth and small for gestational age (SGA) birth compared with United States-born Black women, however variation by country of origin is overlooked. Additionally, the extent that nativity disparities in adverse perinatal outcomes to Black women are explained by individual-level factors remains unclear. METHODS: We conducted a population-based study of nonanomalous singleton live births to United States- and African-born Black women in California from 2011 to 2020 (n = 194,320). We used age-adjusted Poisson regression models to estimate the risk of preterm birth and SGA and reported risk ratios (RR) and 95% confidence intervals (CI). Decomposition using Monte Carlo integration of the g-formula computed the percentage of disparities in adverse outcomes between United States- and African-born women explained by individual-level factors. RESULTS: Eritrean women (RR = 0.4; 95% CI = 0.3, 0.5) had the largest differences in risk of preterm birth and Cameroonian women (RR = 0.5; 95% CI = 0.3, 0.6) in SGA birth, compared with United States-born Black women. Ghanaian women had smaller differences in risk of preterm birth (RR = 0.8; 95% CI = 0.7, 1.0) and SGA (RR = 0.9; 95% CI = 0.8, 1.1) compared with United States-born women. Overall, we estimate that absolute differences in socio-demographic and clinical factors contributed to 32% of nativity-based disparities in the risk of preterm birth and 26% of disparities in SGA. CONCLUSIONS: We observed heterogeneity in risk of adverse perinatal outcomes for African- compared with United States-born Black women, suggesting that nativity disparities in adverse perinatal outcomes were not fully explained by differences in individual-level factors.

Ethnoracial Disparities in Perinatal Outcomes Among Women Veterans.

Objective: Non-Hispanic Black women have increased rates of preterm birth and low infant birth weight. However, we do not know if these disparities replicate in women veterans, a population that may be at further risk for poor perinatal outcomes. This study sought to examine ethnoracial differences in preterm birth and low infant birth weight in veterans. Methods: A national sample of randomly chosen women veterans (i.e., oversampled for residency in high crime neighborhoods) reported information about all pregnancies they have had in their life, demographic characteristics, and history of childhood trauma exposures. The analytic sample was limited to individuals who identified as Hispanic/Latinx, Black, or White (n = 972). Mixed-effects regression models were used to examine ethnoracial differences in gestational age at delivery and infant birth weight, controlling for age at pregnancy, childhood trauma exposure, pregnancy during military service, income, and education. Results: Both Black and Hispanic/Latinx veterans were significantly more likely to have an infant born at lower gestational age (B = -1.04 and B = -1.11, respectively) and lower infant birth weight (B = -195.83 and B = -144.27, respectively) as compared with White veterans in covariate-adjusted models. Black (odds ratio = 3.24, confidence interval = 1.16, 9.09) veterans were more likely to meet the clinical definition of preterm birth as compared with White veterans. Conclusions: Results align with what is seen in the general population regarding ethnoracial disparities in gestational age at delivery and infant birth weight. Findings highlight the critical need for more research on mechanisms and prevention efforts for ethnoracial disparities in perinatal outcomes.

Structural gendered racism and preterm birth inequities in the United States.

Structural gendered racism - the "totality of interconnectedness between structural racism and sexism" - is conceptualized as a fundamental cause of the persistent preterm birth inequities experienced by Black and Indigenous people in the United States. Our objective was to develop a state-level latent class measure of structural gendered racism and examine its association with preterm birth among all singleton live births in the US in 2019. Using previously-validated inequity indicators between White men and Black women across 9 domains (education, employment, poverty, homeownership, health insurance, segregation, voting, political representation, incarceration), we conducted a latent profile analysis to identify a latent categorical variable with k number of classes that have similar values on the observed continuous input variables. Racialized group-stratified multilevel modified Poisson regression models with robust variance and random effects for state assessed the association between state-level classes and preterm birth. We found four distinct latent classes that were all characterized by higher levels of disadvantage for Black women and advantages for White men, but the magnitude of that difference varied by latent class. We found preterm birth risk among Black birthing people was higher across all state-level latent classes compared to White birthing people, and there was some variation of preterm birth risk across classes among Black but not White birthing people. These findings further emphasize the importance of understanding and interrogating the whole system and the need for multifaceted policy solutions.

The Association Between Adverse Childhood Experiences and Preterm Delivery: A Latent Class Approach.

Background: Racial and socioeconomic status (SES) disparities in preterm delivery (PTD) have existed in the United States for decades. Disproportionate maternal exposures to adverse childhood experiences (ACEs) may increase the risk for adverse birth outcomes. Moreover, racial and SES disparities exist in the prevalence of ACEs, underscoring the need for research that examines whether ACEs contribute to racial and SES disparities in PTD. Methods: We examined the relationship between ACEs and PTD in a longitudinal sample of N = 3,884 women from the National Longitudinal Study of Adolescent to Adult Health (1994-2018). We applied latent class analysis to (1) identify subgroups of women characterized by patterns of ACE occurrence; (2) estimate the association between latent class membership (LCM) and PTD, and (3) examine whether race and SES influence LCM or the association between LCM and PTD. Results: Two latent classes were identified, with women in the high ACEs class characterized by a higher probability of emotional abuse, physical abuse, sexual abuse, and foster care placement compared with the low ACEs class, but neither class was associated with PTD. Race and SES did not predict LCM. Conclusions: Our findings suggest that ACEs may not impact PTD risk in previously hypothesized ways. Future research should assess the impact of ACEs on the probability of having live birth pregnancies as well as the role of potential protective factors in mitigating the impact of ACEs on PTD.

Despite treatment, HbA1c ≥ 37 mmol/mol in the first trimester is associated with premature delivery among South Asian women with gestational diabetes mellitus: a retrospective cohort study.

PURPOSE: To examine the effects of first-trimester HbA1c (HbA1c-FT) ≥ 37 mmol/mol on preterm birth (PTB) and large-for-gestational-age (LGA) babies in a retrospective cohort of South Asian pregnant women with gestational diabetes (GDM). METHODS: The cohort (n = 686) was separated into two groups based on HbA1c-FT values: Group A (n = 97) and Group B (n = 589), with values of 37-46 mmol/mol (5.5-6.4%) and < 37 mmol/mol (5.5%), respectively. HbA1c-FT's independent influence on PTB and LGA babies was examined using multivariable logistic regression in groups A and B women. The reference group (Group C) included 2031 non-GDM women with HbA1c-FT < 37 mmol/mol (< 5.5%). The effects of HbA1c-FT on PTB and LGA babies in obese women in Groups A, B, and C (designated as A-ob, B-ob, and C-ob, respectively) were re-analyzed using multivariable logistic regression. RESULTS: Group A GDM women with greater HbA1c-FT had a higher risk for PTB (aOR:1.86, 95% CI:1.10-3.14) but not LGA babies (aOR:1.13, 95%: 0.70-1.83). The risk of PTB was higher for obese women in Group A-ob: aOR 3.28 [95% CI 1.68-6.39]. However, GDM women with normal HbA1c-FT exhibited no elevated risk for PTB: Groups B and B-ob had aORs of 1.30 (95% CI 0.86-1.98) and 1.28 (95% CI 0.88-1.85) respectively. CONCLUSIONS: South Asian GDM women with prediabetic HbA1c FT; 37-46 mmol/mol (5.5-6.4%) are more likely to deliver preterm babies despite treatment, while the risk for LGA babies was the same as non-GDM women.

Lifetime Upward Economic Mobility and US-Born Latina Women's Preterm Birth Rates.

OBJECTIVES: To determine whether Latina women's upward economic mobility from early-life residence in impoverished urban neighborhoods is associated with preterm birth (< 37 weeks, PTB) . METHODS: Multivariate logistic regression analyses were performed on the Illinois transgenerational birth-file with appended US census income information for Hispanic infants (born 1989-1991) and their mothers (born 1956-1976). RESULTS: In Chicago, modestly impoverished-born Latina women (n = 1,674) who experienced upward economic mobility had a PTB rate of 8.5% versus 13.1% for those (n = 3,760) with a lifelong residence in modestly impoverished neighborhoods; the unadjusted and adjusted (controlling for age, marital status, adequacy of prenatal care, and cigarette smoking) RR equaled 0.65 (0.47, 0.90) and 0.66 (0.47, 0.93), respectively. Extremely impoverished-born Latina women (n = 2,507) who experienced upward economic mobility across their life-course had a PTB rate of 12.7% versus 15.9% for those (n = 3,849) who had a lifelong residence in extremely impoverished neighborhoods, the unadjusted and adjusted RR equaled 0.8 (0.63. 1.01) and 0.95 (0.75, 1.22), respectively. CONCLUSIONS FOR PRACTICE: Latina women's upward economic mobility from early-life residence in modestly impoverished urban neighborhoods is associated with a decreased risk of PTB. A similar trend is absent among their peers with an early-life residence in extremely impoverished areas.

"MAMA's is like a second mom:" Client and Staff Experiences in a Comprehensive Social Risk Care Management Program Within a Perinatal Medical Home.

INTRODUCTION: Addressing persistent racial inequities in preterm birth requires innovative health care approaches. The Los Angeles County Maternity Assessment and Management Access Service Synergy Neighborhood program (MAMA's) is a perinatal medical home program designed to alleviate the impacts of chronic stress by addressing social determinants of health. It reduced odds of preterm birth rates in Black participants, yet it is unclear which program components most contributed to this reduction. This study seeks to understand the experiences of staff and clients within the MAMA's program to identify what factors decrease stress, how the program addresses racism and the challenges and opportunities of optimizing health during the COVID-19 pandemic. METHODS: 21 staff and 34 clients completed semi-structured interviews from November 2020-December 2021. Separate interview guides for staff and clients explored experiences within the program, experiences during the COVID-19 pandemic, and how racism affects clients. Interviews were recorded and transcribed. Analysis used a phenomenologic framework. Coding was performed using grounded theory to identify themes. RESULTS: Analysis revealed six key themes: Stressors clients face, barriers for undocumented, Latina, and Spanish-speaking clients, exceptional care, emotional support, naming and responding to racism and discrimination, and impacts of COVID-19 pandemic. DISCUSSION: Staff and clients work together to address social needs in order to address chronic stress and racism in their lives, especially during the COVID-19 pandemic. Interviews revealed relationship building is a cornerstone of the program's success and plays a significant role in alleviating chronic stress in this population.

Addressing anti-black racism in an academic preterm birth initiative: perspectives from a mixed methods case study.

BACKGROUND: Growing recognition of racism perpetuated within academic institutions has given rise to anti-racism efforts in these settings. In June 2020, the university-based California Preterm Birth Initiative (PTBi) committed to an Anti-Racism Action Plan outlining an approach to address anti-Blackness. This case study assessed perspectives on PTBi's anti-racism efforts to support continued growth toward racial equity within the initiative. METHODS: This mixed methods case study included an online survey with multiple choice and open-ended survey items (n = 27) and key informant interviews (n = 8) of leadership, faculty, staff, and trainees working within the initiative. Survey and interview questions focused on perspectives about individual and organizational anti-racism competencies, perceived areas of initiative success, and opportunities for improvement. Qualitative interview and survey data were coded and organized into common themes within assessment domains. RESULTS: Most survey respondents reported they felt competent in all the assessed anti-racism skills, including foundational knowledge and responding to workplace racism. They also felt confident in PTBi's commitment to address anti-Blackness. Fewer respondents were clear on strategic plans, resources allocated, and how the anti-racism agenda was being implemented. Suggestions from both data sources included further operationalizing and communicating commitments, integrating an anti-racism lens across all activities, ensuring accountability including staffing and funding consistent with anti-racist approaches, persistence in hiring Black faculty, providing professional development and support for Black staff, and addressing unintentional interpersonal harms to Black individuals. CONCLUSIONS: This case study contributes key lessons which move beyond individual-level and theoretical approaches towards transparency and accountability in academic institutions aiming to address anti-Black racism. Even with PTBi's strong commitment and efforts towards racial equity, these case study findings illustrate that actions must have sustained support by the broader institution and include leadership commitment, capacity-building via ongoing coaching and training, broad incorporation of anti-racism practices and procedures, continuous learning, and ongoing accountability for both short- and longer-term sustainable impact.

The Black-White Disparity in Preterm Birth: Race or Racism?

Policy Points Racism is an upstream determinant of health that influences health through many midstream and downstream factors. This Perspective traces multiple plausible causal pathways from racism to preterm birth. Although the article focuses on the Black-White disparity in preterm birth, a key population health indicator, it has implications for many other health outcomes. It is erroneous to assume by default that underlying biological differences explain racial disparities in health. Appropriate science-based policies are needed to address racial disparities in health; this will require addressing racism.

Risk of Adverse Pregnancy Outcomes Among Pregnant Individuals With Gestational Diabetes by Race and Ethnicity in the United States, 2014-2020.

Importance: Gestational diabetes, which increases the risk of adverse pregnancy outcomes, has been increasing in frequency across all racial and ethnic subgroups in the US. Objective: To assess whether the frequency of adverse pregnancy outcomes among those in the US with gestational diabetes changed over time and whether the risk of these outcomes differed by maternal race and ethnicity. Design, Setting, and Participants: Exploratory serial, cross-sectional, descriptive study using US National Center for Health Statistics natality data for 1 560 822 individuals with gestational diabetes aged 15 to 44 years with singleton nonanomalous live births from 2014 to 2020 in the US. Exposures: Year of delivery and race and ethnicity, as reported on the birth certificate, stratified as non-Hispanic American Indian, non-Hispanic Asian/Pacific Islander, non-Hispanic Black, Hispanic/Latina, and non-Hispanic White (reference group). Main Outcomes and Measures: Maternal outcomes of interest included cesarean delivery, primary cesarean delivery, preeclampsia or gestational hypertension, intensive care unit (ICU) admission, and transfusion; neonatal outcomes included large for gestational age (LGA), macrosomia (>4000 g at birth), small for gestational age (SGA), preterm birth, and neonatal ICU (NICU) admission, as measured by the frequency (per 1000 live births) with estimation of mean annual percentage change (APC), disparity ratios, and adjusted risk ratios. Results: Of 1 560 822 included pregnant individuals with gestational diabetes (mean [SD] age, 31 [5.5] years), 1% were American Indian, 13% were Asian/Pacific Islander, 12% were Black, 27% were Hispanic/Latina, and 48% were White. From 2014 to 2020, there was a statistically significant increase in the overall frequency (mean APC per year) of preeclampsia or gestational hypertension (4.2% [95% CI, 3.3% to 5.2%]), transfusion (8.0% [95% CI, 3.8% to 12.4%]), preterm birth at less than 37 weeks (0.9% [95% CI, 0.3% to 1.5%]), and NICU admission (1.0% [95% CI, 0.3% to 1.7%]). There was a significant decrease in cesarean delivery (-1.4% [95% CI, -1.7% to -1.1%]), primary cesarean delivery (-1.2% [95% CI, -1.5% to -0.9%]), LGA (-2.3% [95% CI, -2.8% to -1.8%]), and macrosomia (-4.7% [95% CI, -5.3% to -4.0%]). There was no significant change in maternal ICU admission and SGA. In comparison with White individuals, Black individuals were at significantly increased risk of all assessed outcomes, except LGA and macrosomia; American Indian individuals were at significantly increased risk of all assessed outcomes except cesarean delivery and SGA; and Hispanic/Latina and Asian/Pacific Islander individuals were at significantly increased risk of maternal ICU admission, preterm birth, NICU admission, and SGA. Differences in adverse outcomes by race and ethnicity persisted through these years. Conclusions and Relevance: From 2014 through 2020, the frequency of multiple adverse pregnancy outcomes in the US increased among pregnant individuals with gestational diabetes. Differences in adverse outcomes by race and ethnicity persisted.

Integrative Review of Racial Disparities in Perinatal Outcomes Among Beneficiaries of the Military Health System.

OBJECTIVE: To examine the extent to which racial disparities exist in the perinatal outcomes of beneficiaries of the Military Health System (MHS). DATA SOURCES: We searched the PubMed, CINAHL, and Embase databases. STUDY SELECTION: We selected articles published in English in peer-reviewed journals in which the authors examined race in relation to perinatal outcomes among beneficiaries of the MHS. Date of publication was unrestricted through March 2021. DATA EXTRACTION: Twenty-six articles met the inclusion criteria. We extracted data about study design, purpose, sample, setting, and results. We also assigned quality appraisal ratings to each article. DATA SYNTHESIS: In most of the included articles, researchers observed differences in perinatal outcomes between Black and White women. Compared to White women, Black women had greater rates of cesarean birth, preterm birth, low birth weight, and small for gestational age neonates. White women had greater rates of postpartum depression than Black women. CONCLUSION: Racial disparities in very low birth weight newborns and preterm birth may be smaller in the MHS than in the general population of the United States. The overall rates of preterm birth, cesarean birth, and neonatal mortality were lower for beneficiaries of the MHS than in the general population of the United States.

Association of Residence in High-Police Contact Neighborhoods With Preterm Birth Among Black and White Individuals in Minneapolis.

Importance: Police contact may have negative psychological effects on pregnant people, and psychological stress has been linked to preterm birth (ie, birth at <37 weeks' gestation). Existing knowledge of racial disparities in policing patterns and their associations with health suggest redesigning public safety policies could contribute to racial health equity. Objective: To examine the association between community-level police contact and the risk of preterm birth among White pregnant people, US-born Black pregnant people, and Black pregnant people who were born outside the US. Design, Setting, and Participants: This cross-sectional study used medical record data of 745 White individuals, 121 US-born Black individuals, and 193 Black individuals born outside the US who were Minneapolis residents and gave birth to a live singleton at a large health system between January 1 and December 31, 2016. Data were analyzed from March 2019 to October 2020. Exposures: Police contact was measured at the level of the census tract where the pregnant people lived. Police incidents per capita (ie, the number of police incidents divided by the census tract population estimate) were dichotomized into high if the value was in the fourth quartile and low for the remaining three quartiles. Main Outcomes and Measures: Preterm birth status was based on the International Statistical Classification of Diseases and Related Health Problems, 10th revision, Clinical Modification (ICD-10-CM) code. Preterm infants were those with ICD-10-CM codes P07.2 and P07.3 documented in their charts. Results: Of 1059 pregnant people (745 [70.3%] White, 121 [11.4%] US-born Black, 193 [18.2%] Black born outside the US) in the sample, 336 White individuals (45.1%) and 62 Black individuals who were born outside the US (32.1%) gave birth between the ages of 30 and 34 years, while US-born Black individuals gave birth at younger ages, with 49 (40.5%) aged 25 years or younger. The incidence of preterm birth was 6.7% for White individuals (50 pregnant people), 14.0% for US-born Black individuals (17 pregnant people), and 5.7% for Black individuals born outside the US (11 pregnant people). In areas with high police contact vs low police contact, the odds of preterm birth were 90% higher for White individuals (odds ratio [OR], 1.9; 95% CI, 1.9-2.0), 100% higher for US-born Black individuals (OR, 2.0; 95% CI, 1.8-2.2), and 10% higher for Black individuals born outside the US (OR, 1.1; 95% CI, 1.0-1.2). Secondary geospatial analysis further revealed that the proportion of Black residents in Minneapolis census tracts was correlated with the number of police incidents reported between 2012 and 2016 (P = .001). Conclusions and Relevance: In this study, police contact was associated with preterm birth for both Black and White pregnant people. Predominantly Black neighborhoods had greater police contact than predominantly White neighborhoods, indicating that Black pregnant people were more likely to be exposed to police than White pregnant people. These findings suggest that racialized police patterns borne from a history of racism in the United States may contribute to racial disparity in preterm birth.

Endocrine disrupting chemical-associated hair product use during pregnancy and gestational age at delivery: a pilot study.

BACKGROUND: Prenatal endocrine disrupting chemical (EDC) exposure has been associated with increased risk of preterm birth. Non-Hispanic Black women have higher incidence of preterm birth compared to other racial/ethnic groups and may be disproportionately exposed to EDCs through EDC-containing hair products. However, research on the use of EDC-associated hair products during pregnancy and risk of preterm birth is lacking. Therefore, the objective of this pilot study was to estimate associations of prenatal hair product use with gestational age at delivery in a Boston, Massachusetts area pregnancy cohort. METHODS: The study population consisted of a subset of participants enrolled in the Environmental Reproductive and Glucose Outcomes (ERGO) Study between 2018 and 2020. We collected self-reported data on demographics and hair product use using a previously validated questionnaire at four prenatal visits (median: 12, 19, 26, 36 weeks' gestation) and abstracted gestational age at delivery from medical records. We compared gestational age and hair product use by race/ethnicity and used linear regression to estimate covariate-adjusted associations of product use and frequency of use at each study visit with gestational age at delivery. Primary models were adjusted for maternal age at enrollment and delivery method. RESULTS: Of the 154 study participants, 7% delivered preterm. Non-Hispanic Black participants had lower mean gestational age at delivery compared to non-Hispanic White participants (38.2 vs. 39.2 weeks) and were more likely to report ever and more frequent use of hair products. In regression models, participants reporting daily use of hair oils at visit 4 had lower mean gestational age at delivery compared to non-users (ß: -8.3 days; 95% confidence interval: -14.9, -1.6). We did not find evidence of associations at earlier visits or with other products. CONCLUSIONS: Frequent use of hair oils during late pregnancy may be associated with shorter gestational duration. As hair oils are more commonly used by non-Hispanic Black women and represent potentially modifiable EDC exposure sources, this may have important implications for the known racial disparity in preterm birth.

Maternal biological age assessed in early pregnancy is associated with gestational age at birth.

Maternal age is an established predictor of preterm birth independent of other recognized risk factors. The use of chronological age makes the assumption that individuals age at a similar rate. Therefore, it does not capture interindividual differences that may exist due to genetic background and environmental exposures. As a result, there is a need to identify biomarkers that more closely index the rate of cellular aging. One potential candidate is biological age (BA) estimated by the DNA methylome. This study investigated whether maternal BA, estimated in either early and/or late pregnancy, predicts gestational age at birth. BA was estimated from a genome-wide DNA methylation platform using the Horvath algorithm. Linear regression methods assessed the relationship between BA and pregnancy outcomes, including gestational age at birth and prenatal perceived stress, in a primary and replication cohort. Prenatal BA estimates from early pregnancy explained variance in gestational age at birth above and beyond the influence of other recognized preterm birth risk factors. Sensitivity analyses indicated that this signal was driven primarily by self-identified African American participants. This predictive relationship was sensitive to small variations in the BA estimation algorithm. Benefits and limitations of using BA in translational research and clinical applications for preterm birth are considered.