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.

Structural racism, nativity and risk of adverse perinatal outcomes among Black women.

BACKGROUND: Black women in the United States (US) have the highest risk of preterm birth (PTB) and small for gestational age (SGA) births, compared to women of other racial groups. Among Black women, there are disparities by nativity whereby foreign-born women have a lower risk of PTB and SGA compared to US-born women. Differential exposure to racism may confer nativity-based differences in adverse perinatal outcomes between US- and foreign-born Black women. This remains unexplored among US- and African-born women in California. OBJECTIVES: Evaluate the relationship between structural racism, nativity, PTB and SGA among US- and African-born Black women in California. METHODS: We conducted a population-based study of singleton births to US- and African-born Black women in California from 2011 to 2017 (n = 131,424). We examined the risk of PTB and SGA by nativity and neighbourhoods with differing levels of structural racism, as measured by the Index of Concentration at the Extremes. We fit crude and age-adjusted Poisson regression models, estimated using generalized estimating equations, with risk ratios (RR) and 95% confidence intervals (CI) as the effect measure. RESULTS: The proportions of PTB and SGA were 9.7% and 14.5%, respectively, for US-born women, while 5.6% and 8.3% for African-born women. US-born women (n = 24,782; 20.8%) were more likely to live in neighbourhoods with high structural racism compared to African-born women (n = 1474; 11.6%). Structural racism was associated with an elevated risk of PTB (RR 1.19, 95% CI 1.12, 1.26) and SGA (RR 1.19, 95% CI 1.13, 1.25) for all Black women, however, there was heterogeneity by nativity, with US-born women experiencing a higher magnitude of effect than African-born women. CONCLUSIONS: Among Black women in California, exposure to structural racism and the impacts of structural racism on the risk of PTB and SGA varied by nativity.

The Association of Gestational Age and Size with Management Strategies and Outcomes in Symptomatic Neonatal Tetralogy of Fallot.

 In neonatal, symptomatic tetralogy of Fallot (sTOF), data are lacking on whether high-risk groups would benefit from staged (SR) or complete repair (CR). We studied the association of gestational age (GA) at birth and z-score for birth weight (BWz), with management strategy and outcomes in sTOF. California population-based cohort study (2011-2017) of infants with sTOF (defined as catheter or surgical intervention prior to 44 weeks corrected GA) was performed, comparing management strategy and timing by GA and BWz categories. Multivariable models evaluated composite outcomes and days alive and out of hospital (DAOOH) in the first year of life. Among 345 patients (SR = 194; CR = 151), management strategy did not differ by GA or BWz with complete repair defined as prior to 44 weeks corrected gestational age; however, did differ by GA with regard to complete/timely repair (defined as complete repair within first 30 days of life). Full-term and early-term neonates underwent CR 20 (95%CI: - 27.1, - 14.1; p < 0.001) and 15 days (95%CI: - 22.1, - 8.2; p < 0.001) sooner than preterm neonates. Prematurity and major anomaly were associated with mortality or non-cardiac morbidity, while only major anomaly was associated with mortality or cardiac morbidity (OR = 3.5, 95%CI: 1.8,6.7, p < .0001). Full-term infants had greater DAOOH compared to preterm infants (35.2 days, 95%CI: 4.0, 66.5, p = 0.03). LGA infants and those with major anomaly had significantly lower DAOOH. In sTOF, patient specific risk factors such as prematurity and major anomaly were more associated with outcomes than management strategy.

Adverse live-born pregnancy outcomes among pregnant people with anorexia nervosa.

BACKGROUND: Previous findings related to the association of adverse pregnancy outcomes with anorexia nervosa are mixed. OBJECTIVE: This study aimed to investigate the association of adverse live-born pregnancy outcomes with anorexia nervosa using adjustment modeling accounting for confounding factors, and a mediation analysis addressing the contribution of underweight prepregnancy body mass index and gestational weight gain to those outcomes. STUDY DESIGN: The sample included California live-born singletons with births between 2007 and 2021. The administrative data set contained birth certificates linked to hospital discharge records. Anorexia nervosa diagnosis during pregnancy was obtained from International Classification of Diseases codes on hospital discharge records. Adverse pregnancy outcomes examined included gestational diabetes, gestational hypertension, preeclampsia, anemia, antepartum hemorrhage, premature rupture of membranes, premature labor, cesarean delivery, oligohydramnios, placenta previa, chorioamnionitis, placental abruption, severe maternal morbidity, small for gestational age, large for gestational age, low birthweight, and preterm birth (by timing and indication). Risk of each adverse outcome was calculated using Poisson regression models. Unadjusted risk of each adverse outcome was calculated, and then the risks were adjusted for demographic factors. The final adjusted model included demographic factors, anxiety, depression, substance use, and smoking. A mediation analysis was performed to estimate the excess risk of adverse outcomes mediated by underweight prepregnancy body mass index and gestational weight gain below the American College of Obstetricians and Gynecologists recommendation. RESULTS: The sample included 241 pregnant people with a diagnosis of anorexia nervosa and 6,418,236 pregnant people without an eating disorder diagnosis. An anorexia nervosa diagnosis during pregnancy was associated with many adverse pregnancy outcomes in unadjusted models (relative risks ranged from 1.65 [preeclampsia] to 3.56 [antepartum hemorrhage]) in comparison with people without an eating disorder diagnosis. In the final adjusted models, birthing people with an anorexia nervosa diagnosis were more likely to have anemia, preterm labor, oligohydramnios, severe maternal morbidity, a small for gestational age or low-birthweight infant, and preterm birth between 32 and 36 weeks with spontaneous preterm labor (adjusted relative risks ranged from 1.43 to 2.55). Underweight prepregnancy body mass index mediated 7.78% of the excess in preterm births and 18.00% of the excess in small for gestational age infants. Gestational weight gain below the recommendation mediated 38.89% of the excess in preterm births and 40.44% of the excess in low-birthweight infants. CONCLUSION: Anorexia nervosa diagnosis during pregnancy was associated with a number of clinically important adverse pregnancy outcomes in comparison with people without an eating disorder diagnosis. Adjusting for anxiety, depression, substance use, and smoking during pregnancy decreased this risk. A substantial percentage of the excess risk of adverse outcomes was mediated by an underweight prepregnancy body mass index, and an even larger proportion of excess risk was mediated by gestational weight gain below the recommendation. This information is important for clinicians to consider when caring for patients with anorexia nervosa. Considering and treating anorexia nervosa and comorbid conditions and counseling patients about mediating factors such as preconception weight and gestational weight gain may improve live-born pregnancy outcomes among people with anorexia nervosa.

Adverse Maternal Fetal Environment Partially Mediates Disparate Outcomes in Non-White Neonates with Major Congenital Heart Disease.

OBJECTIVE: To determine whether differential exposure to an adverse maternal fetal environment partially explains disparate outcomes in infants with major congenital heart disease (CHD). STUDY DESIGN: Retrospective cohort study utilizing a population-based administrative California database (2011-2017). Primary exposure: Race/ethnicity. Primary mediator: Adverse maternal fetal environment (evidence of maternal metabolic syndrome and/or maternal placental syndrome). OUTCOMES: Composite of 1-year mortality or severe morbidity and days alive out of hospital in the first year of life (DAOOH). Mediation analyses determined the percent contributions of mediators on pathways between race/ethnicity and outcomes after adjusting for CHD severity. RESULTS: Included were 2747 non-Hispanic White infants (reference group), 5244 Hispanic, and 625 non-Hispanic Black infants. Hispanic and non-Hispanic Black infants had a higher risk for composite outcome (crude OR: 1.18; crude OR: 1.25, respectively) and fewer DAOOH (-6 & -12 days, respectively). Compared with the reference group, Hispanic infants had higher maternal metabolic syndrome exposure (43% vs 28%, OR: 1.89), and non-Hispanic Black infants had higher maternal metabolic syndrome (44% vs 28%; OR: 1.97) and maternal placental syndrome exposure (18% vs 12%; OR, 1.66). Both maternal metabolic syndrome exposure (OR: 1.21) and maternal placental syndrome exposure (OR: 1.56) were related to composite outcome and fewer DAOOH (-25 & -16 days, respectively). Adverse maternal fetal environment explained 25% of the disparate relationship between non-Hispanic Black race and composite outcome and 18% of the disparate relationship between Hispanic ethnicity and composite outcome. Adverse maternal fetal environment explained 16% (non-Hispanic Black race) and 21% (Hispanic ethnicity) of the association with DAOOH. CONCLUSIONS: Increased exposure to adverse maternal fetal environment contributes to racial and ethnic disparities in major CHD outcomes.

Residential particulate matter, proximity to major roads, traffic density and traffic volume as risk factors for preterm birth in California.

BACKGROUND: While pollution from vehicle sources is an established risk factor for preterm birth, it is unclear whether distance of residence to the nearest major road or related measures like major road density represent useful measures for characterising risk. OBJECTIVE: To determine whether major road proximity measures (including distance to major road, major road density and traffic volume) are more useful risk factors for preterm birth than other established vehicle-related measures (including particulate matter <2.5 µm in diameter (PM2.5 ) and diesel particulate matter (diesel PM)). METHODS: This retrospective cohort study included 2.7 million births across the state of California from 2011-2017; each address at delivery was geocoded. Geocoding was used to calculate distance to the nearest major road, major road density within a 500 m radius and major road density weighted by truck volume. We measured associations with preterm birth using risk ratios adjusted for target demographic, clinical, socioeconomic and environmental covariates (aRRs). We compared these to the associations between preterm birth and PM2.5 and diesel PM by census tract of residence. RESULTS: Findings showed that whereas higher mean levels of PM2.5 and diesel PM by census tract were associated with a higher risk of preterm birth, living closer to roads or living in higher traffic density areas was not associated with higher risk. Residence in a census tract with a mean PM2.5 in the top quartile compared with the lowest quartile was associated with the highest observed risk of preterm birth (aRR 1.04, 95% CI 1.04, 1.05). CONCLUSIONS: Over a large geographical region with a diverse population, PM2.5 and diesel PM were associated with preterm birth, while measures of distance to major road were not, suggesting that these distance measures do not serve as a proxy for measures of particulate matter in the context of preterm birth.

Risk of early birth by body mass index in a propensity score-matched sample: A retrospective cohort study.

OBJECTIVE: Evaluate the risk of preterm (<37 weeks) or early term birth (37 or 38 weeks) by body mass index (BMI) in a propensity score-matched sample. DESIGN: Retrospective cohort analysis. SETTING: California, USA. POPULATION: Singleton live births from 2011-2017. METHODS: Propensity scores were calculated for BMI groups using maternal factors. A referent sample of women with a BMI between 18.5 and <25.0 kg/m2 was selected using exact propensity score matching. Risk ratios for preterm and early term birth were calculated. MAIN OUTCOME MEASURES: Early birth. RESULTS: Women with a BMI <18.5 kg/m2 were at elevated risk of birth of 28-31 weeks (relative risk [RR] 1.2, 95% CI 1.1-1.4), 32-36 weeks (RR 1.3, 95% CI 1.2-1.3), and 37 or 38 weeks (RR 1.1, 95% CI 1.1-1.1). Women with BMI ≥25.0 kg/m2 were at 1.2-1.4-times higher risk of a birth <28 weeks and were at reduced risk of a birth between 32 and 36 weeks (RR 0.8-0.9) and birth during the 37th or 38th week (RR 0.9). CONCLUSION: Women with a BMI <18.5 kg/m2 were at elevated risk of a preterm or early term birth. Women with BMI ≥25.0 kg/m2 were at elevated risk of a birth <28 weeks. Propensity score-matched women with BMI ≥30.0 kg/m2 were at decreased risk of a spontaneous preterm birth with intact membranes between 32 and 36 weeks, supporting the complexity of BMI as a risk factor for preterm birth. TWEETABLE ABSTRACT: Propensity score-matched women with BMI ≥30 kg/m2 were at decreased risk of a late spontaneous preterm birth.

Mortality and Major Neonatal Morbidity in Preterm Infants with Serious Congenital Heart Disease.

OBJECTIVE: To investigate the trends of 1-year mortality and neonatal morbidities in preterm infants with serious congenital heart disease (CHD). STUDY DESIGN: This cohort study used a population-based administrative dataset of all liveborn infants of 26-36 weeks gestational age with serious CHD born in California between 2011 and 2017. We assessed 1-year mortality and major neonatal morbidities (ie, retinopathy of prematurity, bronchopulmonary dysplasia, necrotizing enterocolitis, intraventricular hemorrhage grade >2, and periventricular leukomalacia) across the study period and compared these outcomes with those in infants without CHD. RESULTS: We identified 1921 preterm infants with serious CHD. The relative risk (RR) of death decreased by 10.6% for each year of the study period (RR, 0.89; 95% CI, 0.84-0.95), and the RR of major neonatal morbidity increased by 8.3% for each year (RR, 1.08; 95% CI, 1.02-1.15). Compared with preterm neonates without any CHD (n = 234 522), the adjusted risk difference (ARD) for mortality was highest at 32 weeks of gestational age (9.7%; 95% CI, 8.3%-11.2%), that for major neonatal morbidity was highest at 28 weeks (21.9%; 95% CI, 17.0%-26.9%), and that for the combined outcome was highest at 30 weeks (26.7%; 95% CI, 23.3%-30.1%). CONCLUSIONS: Mortality in preterm neonates with serious CHD decreased over the last decade, whereas major neonatal morbidities increased. Preterm infants with a gestational age of 28-32 weeks have the highest mortality or morbidity compared with their peers without CHD. These results support the need for specialized and focused medical neonatal care in preterm neonates with serious CHD.

Newborn metabolic vulnerability profile identifies preterm infants at risk for mortality and morbidity.

BACKGROUND: Identifying preterm infants at risk for mortality or major morbidity traditionally relies on gestational age, birth weight, and other clinical characteristics that offer underwhelming utility. We sought to determine whether a newborn metabolic vulnerability profile at birth can be used to evaluate risk for neonatal mortality and major morbidity in preterm infants. METHODS: This was a population-based retrospective cohort study of preterm infants born between 2005 and 2011 in California. We created a newborn metabolic vulnerability profile wherein maternal/infant characteristics along with routine newborn screening metabolites were evaluated for their association with neonatal mortality or major morbidity. RESULTS: Nine thousand six hundred and thirty-nine (9.2%) preterm infants experienced mortality or at least one complication. Six characteristics and 19 metabolites were included in the final metabolic vulnerability model. The model demonstrated exceptional performance for the composite outcome of mortality or any major morbidity (AUC 0.923 (95% CI: 0.917-0.929). Performance was maintained across mortality and morbidity subgroups (AUCs 0.893-0.979). CONCLUSIONS: Metabolites measured as part of routine newborn screening can be used to create a metabolic vulnerability profile. These findings lay the foundation for targeted clinical monitoring and further investigation of biological pathways that may increase the risk of neonatal death or major complications in infants born preterm. IMPACT: We built a newborn metabolic vulnerability profile that could identify preterm infants at risk for major morbidity and mortality. Identifying high-risk infants by this method is novel to the field and outperforms models currently in use that rely primarily on infant characteristics. Utilizing the newborn metabolic vulnerability profile for precision clinical monitoring and targeted investigation of etiologic pathways could lead to reductions in the incidence and severity of major morbidities associated with preterm birth.

Cohort study of respiratory hospital admissions, air quality and sociodemographic factors in preterm infants born in California.

BACKGROUND: Preterm infants suffer from respiratory morbidity especially during the first year of life. OBJECTIVE: To investigate the association of air quality and sociodemographic indicators on hospital admission rates for respiratory causes. METHODS: This is a retrospective cohort study. We identified all live-born preterm infants in California from 2007 to 2012 in a population-based administrative data set and linked them to a data set measuring several air quality and sociodemographic indicators at the census tract level. All sociodemographic and air quality predictors were divided into quartiles (first quartile most favourable to the fourth quartile least favourable). Mixed effect logistic models to account for clustering at the census tract level were used to investigate associations between chronic air quality and sociodemographic indicators respiratory hospital admission during the first year of life. RESULTS: Of 205 178 preterm infants, 5.9% (n = 12 033) were admitted to the hospital for respiratory causes during the first year. In the univariate analysis, comparing the first to the fourth quartile of chronic ozone (risk ratio [RR] 1.29, 95% confidence interval [CI] 1.21, 1.37), diesel (RR 1.10, 95% CI 1.02, 1.17) and particulate matter 2.5 (RR 1.07, 95% CI 1.01, 1.14) exposure were associated with hospital admission during the first year. Following adjustment for confounders, the risk ratios for hospital admission during the first year were 1.53 (95% CI 1.37, 1.72) in relation to educational attainment (per cent of the population over age 25 with less than a high school education) and 1.23 (95% CI 1.09, 1.38) for poverty (per cent of the population living below two times the federal poverty level). CONCLUSIONS: Among preterm infants, respiratory hospital admissions in the first year in California are associated with socioeconomic characteristics of the neighbourhood an individual is living in.

Preterm birth and nativity among Black women with gestational diabetes in California, 2013-2017: a population-based retrospective cohort study.

BACKGROUND: Despite the disproportionate prevalence of gestational diabetes (GDM) and preterm birth (PTB) and their associated adverse perinatal outcomes among Black women, little is known about PTB among Black women with GDM. Specifically, the relationship between PTB by subtype (defined as indicated PTB and spontaneous PT labor) and severity, GDM, and nativity has not been well characterized. Here we examine the risk of PTB by severity (early < 34 weeks, late 34 to 36 weeks) and early term birth (37 to 38 weeks) by nativity among Black women with GDM in California. METHODS: This retrospective cohort study used linked birth certificate and hospital discharge data for 8609 of the 100,691 self-identifying non-Hispanic Black women with GDM who had a singleton live birth between 20 and 44 weeks gestation in California in 2013-2017. Adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were examine risks for PTB, by severity and subtype, and early term birth using multivariate regression modeling. RESULTS: Approximately, 83.9% of Black women with GDM were US-born and 16.1% were foreign-born. The overall prevalence of early PTB, late PTB, and early term birth was 3.8, 9.5, and 29.9%, respectively. Excluding history of prior PTB, preeclampsia was the greatest overall risk factor for early PTB (cOR = 6.7, 95%, CI 5.3 to 8.3), late PTB (cOR = 4.3, 95%, CI 3.8 to 5.0), and early term birth (cOR = 1.8, 95%, CI 1.6 to 2.0). There was no significant difference in the prevalence of PTB by subtypes and nativity (p = 0.5963). Overall, 14.2% of US- compared to 8.9% of foreign-born women had a PTB (early PTB: aOR = 0.56, 95%, CI 0.38 to 0.82; late PTB: aOR = 0.57, 95%, CI 0.45 to 0.73; early term birth: aOR = 0.67, 95%, CI 0.58 to 0.77). CONCLUSIONS: Foreign-born status remained protective of PTB, irrespective of severity and subtype. Preeclampsia, PTB, and GDM share pathophysiologic mechanisms suggesting a need to better understand differences in perinatal stress, chronic disease, and vascular dysfunction based on nativity in future epidemiologic studies and health services research.

Morbidity of Persistent Pulmonary Hypertension of the Newborn in the First Year of Life.

OBJECTIVE: To assess postdischarge mortality and morbidity in infants diagnosed with different etiologies and severities of persistent pulmonary hypertension of the newborn (PPHN), and to identify risk factors for these adverse clinical outcomes. STUDY DESIGN: This was a population-based study using an administrative dataset linking birth and death certificates, hospital discharge and readmissions records from 2005 to 2012 in California. Cases were infants ≥34 weeks' gestational age with International Classification of Diseases,9th edition, codes consistent with PPHN. The primary outcome was defined as postdischarge mortality or hospital readmission during the first year of life. Crude and adjusted risk ratio (aRR) with 95% CIs were calculated to quantify the risk for the primary outcome and to identify risk factors. RESULTS: Infants with PPHN (n = 7847) had an aRR of 3.5 (95% CI, 3.3-3.7) for the primary outcome compared with infants without PPHN (n = 3 974 536), and infants with only mild PPHN (n = 2477) had an aRR of 2.2 (95% CI, 2.0-2.5). Infants with congenital diaphragmatic hernia as the etiology for PPHN had an aRR of 8.2 (95% CI, 6.7-10.2) and infants with meconium aspiration syndrome had an aRR of 4.2 (95% CI, 3.7-4.6) compared with infants without PPHN. Hispanic ethnicity, small for gestational age, severe PPHN, and etiology of PPHN were risk factors for the primary outcome. CONCLUSIONS: The postdischarge morbidity burden of infants with PPHN is large. These findings extend to infants with mild PPHN and etiologies with pulmonary vascular changes that are thought to be short term and recoverable. These data could inform counseling of parents.

An Evaluation of Sexually Transmitted Infection and Odds of Preterm or Early-Term Birth Using Propensity Score Matching.

BACKGROUND: Few studies have examined the relationship between sexually transmitted infections (STIs) and preterm birth (<37 weeks gestation) by subtype (<32 weeks, 32-36 weeks, spontaneous, provider-initiated). Here, we evaluate the odds of preterm (by subtype) and early-term (37 and 38 weeks gestation) birth in women with an STI compared with a propensity score-matched reference population. METHODS: The sample was selected from California births in 2007 to 2012. Sexually transmitted infection was defined as a maternal diagnosis of chlamydia, gonorrhea, or syphilis in the birth certificate or hospital discharge record. A reference sample of women without an STI was selected using exact propensity score matching on maternal factors. Odds of preterm and early-term birth were calculated. RESULTS: Sixteen thousand three hundred twelve women were identified as having an STI during pregnancy and an exact propensity score-matched control was identified for 97.2% (n = 15,860). Women with an indication of syphilis during pregnancy were at 1.6 times higher odds of having a preterm birth and, in particular, at elevated odds of a birth less than 32 weeks due to preterm premature rupture of the membranes or provider-initiated birth (odds ratios 4.0-4.2). Women with gonorrhea were at increased odds of a preterm birth, a birth less than 32 weeks, or an early-term birth (odds ratios 1.2-1.8). Chlamydia did not raise the odds of either a preterm or early-term birth. CONCLUSIONS: Gonorrhea and syphilis increased the odds of a preterm birth. Gonorrhea also increased the odds of an early-term birth. Chlamydia did not raise the odds of an early birth.

High risk of spontaneous preterm birth among infants with gastroschisis.

We examined the association between gastroschisis and preterm birth (PTB, <37 weeks) by subtype. The sample was drawn from singleton live births in California from 2007 to 2012 contained in a birth cohort file maintained by the California Office of Statewide Health Planning and Development (n = 2,891,965; 1,421 with gastroschisis). Relative risks (RRs) and 95% confidence intervals (CIs) were calculated for PTB by gestational age (<34, 34-36, and any <37 weeks) and by type (spontaneous labor with intact membranes, preterm premature rupture of the membranes [PPROM], provider initiated) and were adjusted for maternal characteristics. Over 44.5% of infants with gastroschisis were born preterm because of spontaneous etiologies; notably, 8.4% of infants with gastroschisis were born <34 weeks because of spontaneous etiologies (adjusted RRs 9.1-12.2). Overall, 53.7% of infants with gastroschisis were born preterm compared with only 6.9% of infants without gastroschisis (adjusted RR 15.2, 95% CI 13.6-19.5) and are at particularly high risk of spontaneous PTB. Nearly 9% of infants with gastroschisis delivered <34 weeks, regardless of preterm etiology, indicating that these infants are at great risk for PTB morbidities in addition to the complications from gastroschisis.

Using Index of Concentration at the Extremes as Indicators of Structural Racism to Evaluate the Association with Preterm Birth and Infant Mortality-California, 2011-2012.

Disparities in adverse birth outcomes for Black women continue. Research suggests that societal factors such as structural racism explain more variation in adverse birth outcomes than individual-level factors and societal poverty alone. The Index of Concentration at the Extremes (ICE) measures spatial social polarization by quantifying extremes of deprived and privileged social groups using a single metric and has been shown to partially explain racial disparities in black carbon exposures, mortality, fatal and non-fatal assaults, and adverse birth outcomes such as preterm birth and infant mortality. The objective of this analysis was to assess if local measures of racial and economic segregation as proxies for structural racism are associated and preterm birth and infant mortality experienced by Black women residing in California. California birth cohort files were merged with the American Community Survey by zip code (2011-2012). The ICE was used to quantify privileged and deprived groups (i.e., Black vs. White; high income vs. low income; Black low income vs. White high income) by zip code. ICE scores range from - 1 (deprived) to 1 (privileged). ICE scores were categorized into five quintiles based on sample distributions of these measures: quintile 1 (least privileged)-quintile 5 (most privileged). Generalized linear mixed models were used to test the likelihood that ICE measures were associated with preterm birth or with infant mortality experienced by Black women residing in California. Black women were most likely to reside in zip codes with greater extreme income concentrations, and moderate extreme race and race + income concentrations. Bivariate analysis revealed that greater extreme income, race, and race + income concentrations increased the odds of preterm birth and infant mortality. For example, women residing in least privileged zip codes (quintile 1) were significantly more likely to experience preterm birth (race + income ICE OR = 1.31, 95% CI = 1.72-1.46) and infant mortality (race + income ICE OR = 1.70, 95% CI = 1.17-2.47) compared to women living in the most privileged zip codes (quintile 5). Adjusting for maternal characteristics, income, race, and race + income concentrations remained negatively associated with preterm birth. However, only race and race + income concentrations remained associated with infant mortality. Findings support that ICE is a promising measure of structural racism that can be used to address racial disparities in preterm birth and infant mortality experienced by Black women in California.

Previous Adverse Outcome of Term Pregnancy and Risk of Preterm Birth in Subsequent Pregnancy.

Objective Evaluate risk of preterm birth (PTB, < 37 completed weeks' gestation) among a population of women in their second pregnancy with previous full term birth but other adverse pregnancy outcome. Methods The sample included singleton live born infants between 2007 and 2012 in a birth cohort file maintained by the California Office of Statewide Health Planning and Development. The sample was restricted to women with two pregnancies resulting in live born infants and first birth between 39 and 42 weeks' gestation. Logistic regression was used to calculate the risk of PTB in the second birth for women with previous adverse pregnancy outcome including: small for gestational age (SGA) infant, preeclampsia, placental abruption, or neonatal death (≤ 28 days). Risks were adjusted for maternal factors recorded for second birth. Results The sample included 133,622 women. Of the women with any previous adverse outcome, 4.7% had a PTB while just 3.0% of the women without a previous adverse outcome delivered early (relative risk adjusted for maternal factors known at delivery 1.4, 95% CI 1.3-1.5). History of an SGA infant, placental abruption, or neonatal death increased the adjusted risk of PTB in their second birth by 1.5-3.7-fold. History of preeclampsia did not elevate the risk of a preterm birth in the subsequent birth. Conclusions for Practice The findings indicate that women with previous SGA infant, placental abruption, or neonatal death, despite a term delivery, may be at increased risk of PTB in the subsequent birth. These women may be appropriate participates for future interventions aimed at reduction in PTB.

An Online Geographic Data Visualization Tool to Relate Preterm Births to Environmental Factors.

Preterm birth (<37 weeks gestation) continues to be a significant cause of disease and death in the United States. Its complex causes are associated with several genetic, biological, environmental, and sociodemographic factors. Organizing and visualizing various data that may be related to preterm birth is an essential step for pattern exploration and hypothesis generation and presents an opportunity to increase public and stakeholder involvement. In this article, we describe a collaborative effort to create an online geographic data visualization tool using open software to explore preterm birth in Fresno County, where rates are the highest in California. The tool incorporates information on births, environmental exposures, sociodemographic characteristics, the built environment, and access to care. We describe data sets used to build the tool, the data-hosting platform, and the process used to engage stakeholders in its creation. We highlight an important example of how collaboration can increase the utility of geographic data visualization to improve public health and address health equity in birth outcomes.

Patterns of Preterm Birth among Women of Native Hawaiian and Pacific Islander Descent.

OBJECTIVE: To describe the characteristics and risk factors for preterm birth in Hawaiian and Pacific Islander women. STUDY DESIGN: Retrospective cohort study of 10,470 women of Hawaiian or Pacific Islander descent drawn from a population-based birth cohort dataset in California. Variables were examined across preterm birth subtype (spontaneous, provider initiated) and by gestational age grouping (early preterm birth and late preterm birth) and all preterm births. RESULTS: Hawaiian/Pacific Islander women were at higher risk for preterm birth when they had fewer than three prenatal visits; were underweight, reported tobacco, alcohol, or illicit drugs use in pregnancy; had a diagnosis of anemia, gestational diabetes, preexisting diabetes, or hypertension with or without pre-eclampsia; or had a history of previous preterm birth. Obesity was found to be protective for preterm birth. CONCLUSION: Women of Hawaiian and Pacific Islander descent demonstrate a similar yet unique constellation of risk and protective factors for preterm birth as compared with other groups at high risk for preterm birth. Interventions aimed to prevent preterm birth need to support the specific needs of this population.

Hypertensive Disorders of Pregnancy and Preterm Birth Rates among Black Women.

OBJECTIVE: The objective of this study was to investigate the role of gestational hypertension (gHTN) and chronic hypertension (cHTN) on rates of preterm birth (PTB) among black women. STUDY DESIGN: Singleton live births between 20 and 44 weeks' gestation among black women in California from 2007 to 2012 were used for analysis. Risk of PTB by subtype and gestational age among women with cHTN or gHTN, including preeclampsia, was calculated via Poisson's logistic regression modeling. Risks were adjusted for maternal factors associated with increased risk of PTB. RESULTS: A total of 154,950 women met the inclusion criteria. Of the 5,948 women in the sample with cHTN, 26.2% delivered preterm; for the 11,728 women with gHTN, 21.6% delivered preterm. Women with gHTN or cHTN had a higher risk of medically indicated and spontaneous PTB, both at less than 32 and 32 to 36 weeks, when compared with nonhypertensive women (adjusted relative risks [aRRs]: 3.4-11.6). Women with superimposed preeclampsia had higher risks of spontaneous (aRR: 2.8, 95% confidence interval [CI]: 2.3-3.4) and medically indicated PTB (aRR: 2.8, 95% CI: 2.0-3.8), especially PTB < 32 weeks, when compared with women with preeclampsia. CONCLUSION: Among black women, superimposed preeclampsia increased the risk for spontaneous and medically indicated PTB, especially PTB < 32 weeks.