Changes in Socioeconomic Disparities for Traffic-Related Air Pollution Exposure During Pregnancy Over a 20-Year Period in Texas.

Importance: Air pollution presents clear environmental justice issues. However, few studies have specifically examined traffic-related air pollution (TRAP), a source driven by historically racist infrastructure policies, among pregnant individuals, a population susceptible to air pollution effects. How these disparities have changed over time is also unclear but has important policy implications. Objective: To examine changes in TRAP exposure by sociodemographic characteristics among recorded pregnancies over a 20-year period. Design, Setting, and Participants: This population-based birth cohort study used descriptive analysis among pregnant individuals in Texas from 1996 to 2016. All pregnant individuals with valid residential address, socioeconomic, and demographic data were included. Individual-level race and ethnicity, education, and maternal birthplace data were extracted from birth certificates and neighborhood-level household income and historical neighborhood disinvestment (ie, redlining) data were assessed via residential addresses. Data analysis occurred between June 2022 and June 2023. Main Outcomes and Measures: The main outcome, TRAP exposure at residential addresses, was assessed via traffic levels, represented by total and truck-specific vehicle miles traveled (VMT) within 500 m; nitrogen dioxide (no2) concentrations from a spatial-temporal land use regression model (ie, vehicle tailpipe emissions); and National Air Toxic Agency cancer risk index from on-road vehicle emissions. TRAP exposure differences were assessed by sociodemographic indicators over the 1996 to 2016 period. Results: Among 7 043 598 pregnant people (mean [SD] maternal age, 26.8 [6.1] years) in Texas from 1996 to 2016, 48% identified as Hispanic or Latinx, 4% identified as non-Hispanic Asian or Pacific Islander, 12% identified as non-Hispanic Black, and 36% identified as non-Hispanic White. There were differences in TRAP for pregnant people by all sociodemographic variables examined. The absolute level of these disparities decreased from 1996 to 2016, but the relative level of these disparities increased: for example, in 1996, non-Hispanic Black pregnant individuals were exposed to a mean (SD) 15.3 (4.1) ppb of no2 vs 13.5 (4.4) ppb of no2 for non-Hispanic White pregnant individuals, compared with 2016 levels of 6.7 (2.4) ppb no2 for Black pregnant individuals and 5.2 (2.4) ppb of no2 for White pregnant individuals. Large absolute and relative differences in traffic levels were observed for all sociodemographic characteristics, increasing over time. For example, non-Hispanic Black pregnant individuals were exposed to a mean (SD) of 22 836 (32 844) VMT within 500 m of their homes, compared with 12 478 (22 870) VMT within 500 m of the homes of non-Hispanic White pregnant individuals in 2016, a difference of 83%. Conclusions and Relevance: This birth cohort study found that while levels of air pollution disparities decreased in absolute terms over the 20 years of the study, relative disparities persisted and large differences in traffic levels remained, requiring renewed policy attention.

Use of Chemical Hair Straighteners and Fecundability in a North American Preconception Cohort.

Chemical hair straighteners ("relaxers") are used by millions of North Americans, particularly women of color. Hair relaxers may contain endocrine-disrupting compounds, which can harm fertility. We evaluated the association between hair relaxer use and fecundability among 11,274 participants from Pregnancy Study Online (PRESTO), a North American preconception cohort study. During 2014-2022, participants completed a baseline questionnaire in which they reported their history of relaxer use and completed follow-up questionnaires every 8 weeks for 12 months or until pregnancy, whichever came first. We used multivariable-adjusted proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs). Relative to never use, fecundability was lower among current (FR = 0.81, 95% CI: 0.64, 1.03) and former (FR = 0.89, 95% CI: 0.81, 0.98) users of hair relaxers. FRs for first use of hair relaxers at ages <10, 10-19, and ≥20 years were 0.73 (95% CI: 0.55, 0.96), 0.93 (95% CI: 0.83, 1.04), and 0.85 (95% CI: 0.74, 0.98), respectively. Fecundability was lowest among those with longer durations of use (≥10 years vs. never: FR = 0.71, 95% CI: 0.54, 0.91) and more frequent use (≥5 times/year vs. never: FR = 0.82, 95% CI: 0.60, 1.11), but associations were nonmonotonic. In this preconception cohort study, use of chemical hair straighteners was associated with slightly reduced fecundability.

A randomized trial of web-based fertility-tracking software and fecundability.

OBJECTIVE: To assess the effect of randomization to FertilityFriend.com, a mobile computing fertility-tracking app, on fecundability. DESIGN: Parallel non-blinded randomized controlled trial nested within the Pregnancy Study Online (PRESTO), a North American preconception cohort. PATIENT(S): Female participants aged 21 to 45 years attempting conception for ≤6 menstrual cycles at enrolment (2013-2019). INTERVENTION: Randomization (1:1) of 5532 participants to receive a premium Fertility Friend (FF) subscription. MAIN OUTCOME MEASURE(S): Fecundability (per-cycle probability of conception). Participants completed bimonthly follow-up questionnaires until pregnancy or a censoring event, whichever came first. We first performed an intent-to-treat analysis of the effect of FF randomization on fecundability. In secondary analyses, we used a per-protocol approach that accounted for adherence in each trial arm. In both analyses, we used proportional probabilities regression models to estimate fecundability ratios (FR) and 95% confidence intervals (CI) comparing those randomized vs. not randomized and applied inverse probability weights to account for loss-to-follow-up (intent-to-treat and per-protocol analyses) and adherence (per-protocol analyses only). RESULTS: Using life-table methods, 64% of the 2775 participants randomized to FF and 63% of the 2767 participants not randomized to FF conceived during 12 cycles; these respective percentages were each 70% among those with 0-1 cycles of attempt time at enrolment. Of those randomized to FF, 72% were defined as adherent (68% of observed menstrual cycles). In intent-to-treat analyses, there was no appreciable association overall (FR = 0.97; 95% CI, 0.90-1.04) or within strata of pregnancy attempt time at enrolment, age, education, or other characteristics. In per-protocol analyses, we observed little association overall (FR = 1.06; 95% CI, 0.99-1.14), but weak-to-moderate positive associations among participants who had longer attempt times at enrolment (FR = 1.15; 95% CI, 0.98-1.35 for 3-4 cycles; FR = 1.14; 95% CI, 0.87-1.48 for 5-6 cycles), were aged <25 years (FR = 1.29; 95% CI, 1.01-1.66), had ≤12 years of education (FR = 1.32; 95% CI, 0.92-1.89), or were non-users of hormonal contraception within 3 months before enrolment (FR = 1.10; 95% CI, 1.02-1.19). CONCLUSION: No appreciable associations were observed in intent-to-treat analyses. In secondary per-protocol analyses that accounted for adherence, randomization to FF was associated with slightly greater fecundability among selected subgroups of participants; however, these results are susceptible to unmeasured confounding.

Antepartum and intrapartum stillbirth rates across gestation: a cross-sectional study using the revised foetal death reporting system in the U.S.

BACKGROUND: There is a renewed call to address preventable foetal deaths in high-income countries, especially where progress has been slow. The Centers for Disease Control and Prevention released publicly, for the first time, the initiating cause and estimated timing of foetal deaths in 2014. The objective of this study is to describe risk and characteristics of antepartum versus intrapartum stillbirths in the U.S., and frequency of pathological examination to determine cause. METHODS: We conducted a cross-sectional study of singleton births (24-43 weeks) using 2014 U.S. Fetal Death and Natality data available from the National Center for Health Statistics. The primary outcome was timing of death (antepartum (n = 6200), intrapartum (n = 453), and unknown (n = 5403)). Risk factors of interest included maternal sociodemographic, behavioural, medical and obstetric factors, along with foetal sex. We estimated gestational week-specific stillbirth hazard, risk factors for intrapartum versus antepartum stillbirth using multivariable log-binomial regression models, conditional probabilities of intrapartum and antepartum stillbirth at each gestational week, and frequency of pathological examination by timing of death. RESULTS: The gestational age-specific stillbirth hazard was approximately 2 per 10,000 foetus-weeks among preterm gestations and > 3 per 10,000 foetus-weeks among term gestations. Both antepartum and intrapartum stillbirth risk increased in late-term and post-term gestations. The risk of intrapartum versus antepartum stillbirth was higher among those without a prior live birth, relative to those with at least one prior live birth (RR 1.32; 95% CI 1.08-1.61) and those with gestational hypertension, relative to those with no report of gestational hypertension (RR 1.47; 95% CI 1.09-1.96), and lower among Black, relative to white, individuals (RR 0.70; 95% CI 0.55-0.89). Pathological examination was not performed/planned in 25% of known antepartum stillbirths and 29% of known intrapartum stillbirths. CONCLUSION: These findings suggest greater stillbirth risk in the late-term and post-term periods. Primiparous mothers had greater risk of intrapartum than antepartum still birth, suggesting the need for intrapartum interventions for primiparous mothers in this phase of pregnancy to prevent some intrapartum foetal deaths. Efforts are needed to improve understanding, prevention and investigation of foetal deaths as well as improve stillbirth data quality and completeness in the United States.

African American Unemployment and the Disparity in Periviable Births.

Periviable infants (i.e., born before 26 complete weeks of gestation) represent fewer than .5% of births in the US but account for 40% of infant mortality and 20% of billed hospital obstetric costs. African American women contribute about 14% of live births in the US, but these include nearly a third of the country's periviable births. Consistent with theory and with periviable births among other race/ethnicity groups, males predominate among African American periviable births in stressed populations. We test the hypothesis that the disparity in periviable male births among African American and non-Hispanic white populations responds to the African American unemployment rate because that indicator not only traces, but also contributes to, the prevalence of stress in the population. We use time-series methods that control for autocorrelation including secular trends, seasonality, and the tendency to remain elevated or depressed after high or low values. The racial disparity in male periviable birth increases by 4.45% for each percentage point increase in the unemployment rate of African Americans above its expected value. We infer that unemployment-a population stressor over which our institutions exercise considerable control-affects the disparity between African American and non-Hispanic white periviable births in the US.

Long-term Outcomes for Teen Mothers Who Participated in a Mentoring Program to Prevent Repeat Teen Pregnancy.

BACKGROUND: Each year in the United States (US), one million adolescents are pregnant, of which approximately 20% are repeat pregnancies. Adolescent motherhood is associated with lower educational attainment, socioeconomic status and poorer health outcomes. A mentoring program called the Maikuru Program conducted from 2011 to 2015, was designed to teach young mothers under 20 years old how to face daily life challenges, to support them by pairing them with an adult mentor, and prevent a subsequent pregnancy during their teens. The goal of the present study was to examine educational attainment, employment and pregnancies of these adolescent mothers 1-5 years post program. METHODS: Former participants of the Maikuru Program were contacted by telephone and/or Facebook in 2016 to conduct a survey about education attainment, employment status, number of subsequent children delivered, and satisfaction with the program. RESULTS: Nineteen of 51 participants (37%) were reached to complete the survey. Of those who responded, all were in high school or had graduated, nearly half were pursuing some form of higher education and 12 (63%) were currently employed. Nine mothers had given birth to another child; only two (10.5%) were known to be less than 20 years old at the time. All participants reported positive perceptions of the program and would recommend it to other adolescent mothers. CONCLUSION: Educational achievement and employment were high among a modest proportion of adolescent mothers who had participated in a culturally tailored, teen mother-adult mentoring program. Repeat teen pregnancy was infrequent and the mentoring program was perceived as contributing to the success of those who responded to the follow-up. A future randomized trial based on this model may confirm these findings.

Racial disparities in the transgenerational transmission of low birthweight risk.

Objective: To examine the association of maternal low birthweight (LBW) with infant LBW and infant LBW subgroups (i.e. moderate and very LBW), overall and among non-Hispanic (NH) white and NH black mothers. Design: We conducted a population-based cohort study in Allegheny County, Pennsylvania, using linked birth record data of NH white and NH black mother-infant pairs (N = 6,633) born in 1979-1998 and 2009-2011, respectively. The exposure of interest was maternal LBW (birthweight <2500 grams) while the outcomes were infant LBW and LBW subgroups - moderate LBW (1,500-2,499 grams) or very LBW (<1,500 grams). Logistic regression (binomial and multinomial) models were used to estimate adjusted Odds Ratios (ORs), Relative Risk Ratios (RRRs), and related 95% confidence intervals (CI). Stratified analyses were conducted to assess effect modification by mothers' race. Results: Maternal LBW was associated with 1.53 (95%CI: 1.15-2.02) and 1.75 (95%CI: 1.29-2.37) -fold increases in risk of infant LBW and MLBW, respectively, but not VLBW (RRR = 0.86; 95%CI: 0.44-1.70). In race-stratified models, maternal LBW-infant LBW associations were observed among NH blacks (OR = 1.88; 95%CI: 1.32-2.66) and not among NH whites (OR = 1.03; 95%CI: 0.62-1.73) (P for interaction = 0.07). Among NH blacks, maternal LBW was associated with a 2.18 (95%CI: 1.49, 3.20) -fold increase in risk of infant MLBW, but not VLBW (RRR = 1.12; 95%CI: 0.54, 2.35). Among NH whites, LBW subgroup analyses could not be performed due to small numbers of VLBW infants among LBW mothers. Conclusion: Mothers who were LBW at their own birth were more likely to have MLBW infants. Maternal race modified associations of maternal LBW with infant LBW, particularly infant MLBW. Further research is needed in this area to understand the potential mechanisms involved in the transgenerational transmission of LBW risk and race-specific differences in the transmission.

Racial Differences in the Association Between Maternal Antenatal Depression and Preterm Birth Risk: A Prospective Cohort Study.

BACKGROUND: In the United States, racial/ethnic disparities in preterm birth (PTB) are well documented, but explanations for why the disparity persists remain to be fully explored. We examined racial/ethnic differences in the association of maternal antenatal depression with PTB (<37 completed weeks of gestation) risk. METHODS: In a prospective cohort study, participants (n = 2073) included non-Hispanic (NH) black, NH white, Asian, and Hispanic women who received prenatal care at a university obstetric clinic January 2004-March 2010, and delivered at the university's hospital. We obtained data from self-reported questionnaires and electronic medical records. We assessed antenatal depression using the Patient Health Questionnaire-9 and self-reported antenatal antidepressant medication use. Poisson regression models were used to estimate the association between antenatal depression and PTB risk, within strata of race/ethnicity. RESULTS: NH black (risk ratio [RR] = 1.89; 95% confidence interval [CI]: 0.94, 3.80), NH white (RR = 1.58, 95% CI: 1.04, 2.39), and Asian (RR = 2.06; 95% CI: 0.69, 6.13) women with antenatal depression were at increased risk for delivering preterm infants, compared with women without antenatal depression, although the associations were statistically significant only among NH white women. There was no evidence of an association between antenatal depression and risk of PTB among Hispanic women (RR = 0.96; 95% CI: 0.28, 3.25); p-value for interaction = 0.81. CONCLUSION: Our findings suggest race-specific associations of antenatal depression with an increased risk of delivering a preterm infant, supporting the importance of considering race/ethnicity when examining risk factors for health outcomes.

Sex-specific associations of maternal birthweight with offspring birthweight in the Omega study.

PURPOSE: We investigated nonlinear and offspring sex-specific associations of maternal birthweight (BW) with offspring BW among participants of the Omega study, a pregnancy cohort. METHODS: Maternal BW was modeled as a continuous variable, linear spline and binary variable indicating low birthweight (LBW; <2500 vs. ≥2500 grams). Offspring BW was modeled as a continuous and binary variable in regression models. Nonlinearity was assessed using likelihood ratio tests (LRTs) in marginal linear spline models. RESULTS: For every 100-gram increase of maternal BW, offspring BW increased by 22.29 (95% CI: 17.57, 27.02) or 23.41 (95% CI: 6.87, 39.96) grams among mothers with normal BW or born macrosomic, respectively, but not among LBW mothers (ß = -8.61 grams; 95% CI: -22.88, 5.65; LRT P-value = .0005). For every 100-gram increase in maternal BW, BW of male offspring increased 23.47 (95% CI: 16.75, 30.19) or 25.21 (95% CI: 4.35, 46.07) grams among mothers with normal BW or born macrosomic, respectively, whereas it decreased 31.39 grams (95% CI: -51.63, -11.15) among LBW mothers (LRT P-value < .0001). Corresponding increases in BW of female offspring (16-22 grams) did not differ among mothers with LBW, normal BW or macrosomia (LRT P-value = .9163). CONCLUSIONS: Maternal and offspring BW associations are evident among normal BW and macrosomic mothers. These associations differ by offspring sex.

Transgenerational Transmission of Preterm Birth Risk: The Role of Race and Generational Socio-Economic Neighborhood Context.

Objectives We investigated associations of mothers' preterm birth (PTB) status with her infants' PTB risk. We also examined whether this relationship differs by mothers' race and generational socio-economic neighborhood context. Methods Participants were 6592 non-Hispanic (NH) white and NH black mother-infant pairs born in 2009-2011 and 1979-1998, respectively, in Allegheny County, Pennsylvania. Birth records were used to determine gestational age at birth, PTB status (<37 completed weeks of gestation), and PTB subgroups-late and early PTB (34-36 weeks and <34 completed weeks of gestation, respectively). Census data on tract racial composition and household income were used to characterize residential race and economic environment. Logistic regression models were used to calculate Odds Ratios (ORs), Relative Risk Ratios (RRR), and 95% confidence intervals (CIs). Stratified analyses were conducted to assess effect modification. Results Overall, 8.21, 6.63 and 1.58% infants had PTB, LPTB, and EPTB, respectively. Maternal PTB status was associated with a 46% increase in infant PTB (95% CI: 1.08-1.98), EPTB (95% CI: 0.80-2.69), and LPTB (95% CI: 1.04-2.04) risk. Maternal PTB-infant PTB associations, particularly maternal PTB-infant LPTB associations, were stronger among NH blacks, mothers in neighborhoods with a high percentage of NH black residents in both generations, or mothers who moved to neighborhoods with a higher percentage of NH black residents. Conclusions for Practice Race and generational socio-economic neighborhood context modify transgenerational transmission of PTB risk. These findings are important for identification of at-risk populations and to inform future mechanistic studies.

Daughters of Mothers Who Smoke: A Population-based Cohort Study of Maternal Prenatal Tobacco use and Subsequent Prenatal Smoking in Offspring.

BACKGROUND: Prenatal exposure to tobacco is associated with adverse health outcomes for the mother and child, and has been associated with an increased risk of tobacco smoking and nicotine dependence in offspring. The objective of this study was to examine the risk of prenatal smoking, among daughters, associated with maternal prenatal smoking. METHODS: We used a population-based cohort study design, with linked vital records data of mothers and daughters delivering 1984-96 and 1996-2013, respectively, in Washington State. The exposure of interest was mothers' prenatal smoking (any vs. no smoking at any time during pregnancy), while the outcome was daughters' prenatal smoking (similarly assessed). We used multivariable log-binomial regression to obtain estimates of the relative risk (RR) and 95% confidence interval (CI). RESULTS: Daughters exposed to maternal prenatal smoking were more likely to smoke during their pregnancy, compared to unexposed daughters (RR 1.78, 95% CI 1.72, 1.84, adjusted for the year the daughter delivered, her marital status and educational attainment, and the mothers' race/ethnicity). CONCLUSIONS: In this relatively young population, we found that daughters exposed to maternal prenatal smoking have an increased risk of smoking later on during their own pregnancy, emphasizing the importance of exposures during the prenatal period. The mechanisms leading to prenatal smoking are multifactorial and likely include behavioural, genetic, epigenetic and environmental factors. An understanding of this risk factor for prenatal smoking may guide health care providers to better target smoking cessation interventions to at-risk populations.

Association of neighborhood context with offspring risk of preterm birth and low birthweight: A systematic review and meta-analysis of population-based studies.

Findings from studies investigating associations of residential environment with poor birth outcomes have been inconsistent. In a systematic review and meta-analysis, we examined associations of neighborhood disadvantage with preterm birth (PTB) and low birthweight (LBW), and explored differences in relationships among racial groups. Two reviewers searched English language articles in electronic databases of published literature. We used random effects logistic regression to calculate odds ratios (and 95% confidence intervals) relating neighborhood disadvantage with PTB and LBW. Neighborhood disadvantage, most disadvantaged versus least disadvantaged neighborhoods, was defined by researchers of included studies, and comprised of poverty, deprivation, racial residential segregation or racial composition, and crime. We identified 1314 citations in the systematic review. The meta-analyses included 7 PTB and 14 LBW cross-sectional studies conducted in the United States (U.S.). Overall, we found 27% [95%CI: 1.16, 1.39] and 11% [95%CI: 1.07, 1.14] higher risk for PTB and LBW among the most disadvantaged compared with least disadvantaged neighborhoods. No statistically significant association was found in meta-analyses of studies that adjusted for race. In race-stratified meta-analyses models, we found 48% [95%CI: 1.25, 1.75] and 61% [95%CI: 1.30, 2.00] higher odds of PTB and LBW among non-Hispanic white mothers living in most disadvantaged neighborhoods compared with those living in least disadvantaged neighborhoods. Similar, but less strong, associations were observed for PTB (15% [95%CI: 1.09, 1.21]) and LBW (17% [95%CI: 1.10, 1.25]) among non-Hispanic black mothers. Neighborhood disadvantage is associated with PTB and LBW, however, associations may differ by race. Future studies evaluating causal mechanisms underlying the associations, and racial/ethnic differences in associations, are warranted.

Shots by STFM: value of immunization software to family medicine residency directors: a CERA study.

BACKGROUND AND OBJECTIVES: The Group on Immunization Education (GIE) of the Society of Teachers of Family Medicine (STFM) has developed Shots by STFM immunization software, which is available free of charge for a variety of platforms. It is routinely updated with the Center for Disease Control and Prevention's (CDC's) most recent immunization schedules. Successful development and marketing of teaching resources requires periodic evaluation of their use and value to their target audience. This study was undertaken to evaluate the 2011 version of Shots by STFM. METHODS: Family medicine residency directors were surveyed about their use of Shots by STFM for teaching residents and their ratings of its features. RESULTS: The response rate for the survey was 38% (172/452). While awareness of Shots by STFM among responding residency directors was low (57%), ratings by those using the resource were excellent. Thirty percent of respondents recommend or require their residents to use Shots by STFM. CONCLUSIONS: Better marketing of Shots by STFM to family medicine residency directors seems to be indicated.