Preconception dietary glycemic index and risk for large-for-gestational age births.

OBJECTIVES: Diets with a high glycemic index (GI) leading to elevated postprandial glucose levels and hyperinsulinemia during pregnancy have been inconsistently linked to an increased risk for large-for-gestational-age (LGA) births. The effects of prepregnancy dietary GI on LGA risk are, to our knowledge, unknown. We examined the association of prepregnancy dietary GI with LGA births and joint associations of GI and maternal overweight/obesity and infant sex with LGA births among 10 188 infants born without congenital anomalies from 1997 to 2011, using data from the National Birth Defects Prevention Study (NBDPS). The aim of this study was to investigate this association among infants without major congenital anomalies (controls) who participated in the NBDPS and to evaluate how prepregnancy BMI and infant sex may modify this association on the additive scale. METHODS: Dietary intake was ascertained using a 58-item food frequency questionnaire. We dichotomized dietary GI into high and low categories using spline regression models. Infants with a birth weight at or above the 90th percentile for gestational age and sex, according to a U.S. population reference, were considered LGA. We used logistic regression to obtain odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of the infants, 859 (9%) had a high dietary GI (cut-point: 59), and 1244 infants (12%) were born LGA. Unadjusted analysis suggested an inverse association between high dietary GI and LGA (OR, 0.79; 95% CI, 0.62-0.99). No association was observed in multivariable models when comparing high dietary GI intake between LGA births and all other births (OR, 0.94; 95% CI, 0.74-1.20) or when excluding small-for-gestational-age (SGA) births (OR, 0.94; 95% CI, 0.73-1.19). No joint associations with maternal overweight/obesity or infant sex were observed. CONCLUSION: High prepregnancy maternal GI was not associated with LGA births independently of or jointly with other factors.

Validity of Birth Certificate Data Compared With Hospital Discharge Data in Reporting Maternal Morbidity and Disparities.

A growing number of studies are using birth certificate data, despite data-quality concerns, to study maternal morbidity and associated disparities. We examined whether conclusions about the incidence of maternal morbidity, including Black-White disparities, differ between birth certificate data and hospitalization data. Using linked birth certificate and hospitalization data from California and Michigan for 2018 (N=543,469), we found that maternal morbidity measures using birth certificate data alone are substantially underreported and have poor validity. Furthermore, the degree of underreporting in birth certificate data differs between Black and White individuals and results in erroneous inferences about disparities. Overall, Black-White disparities were more modest in the birth certificate data compared with the hospitalization data. Birth certificate data alone are inadequate for studies of maternal morbidity and associated racial disparities.

Structural Racism, Mass Incarceration, and Racial and Ethnic Disparities in Severe Maternal Morbidity.

Importance: Racial and ethnic inequities in the criminal-legal system are an important manifestation of structural racism. However, how these inequities may influence the risk of severe maternal morbidity (SMM) and its persistent racial and ethnic disparities remains underinvestigated. Objective: To examine the association between county-level inequity in jail incarceration rates comparing Black and White individuals and SMM risk in California. Design, Setting, and Participants: This population-based cross-sectional study used state-wide data from California on all live hospital births at 20 weeks of gestation or later from January 1, 1997, to December 31, 2018. Data were obtained from hospital discharge and vital statistics records, which were linked with publicly available county-level data. Data analysis was performed from January 2022 to February 2023. Exposure: Jail incarceration inequity was determined from the ratio of jail incarceration rates of Black individuals to those of White individuals and was categorized as tertile 1 (low), tertile 2 (moderate), tertile 3 (high), with mean cutoffs across all years of 0 to 2.99, 3.00 to 5.22, and greater than 5.22, respectively. Main Outcome and Measures: This study used race- and ethnicity-stratified mixed-effects logistic regression models with birthing people nested within counties and adjusted for individual- and county-level characteristics to estimate the odds of non-blood transfusion SMM (NT SMM) and SMM including blood transfusion-only cases (SMM; as defined by the Centers for Disease Control and Prevention SMM index) associated with tertiles of incarceration inequity. Results: This study included 10 200 692 births (0.4% American Indian or Alaska Native, 13.4% Asian or Pacific Islander, 5.8% Black, 50.8% Hispanic or Latinx, 29.6% White, and 0.1% multiracial or other [individuals who self-identified with ≥2 racial groups and those who self-identified as "other" race or ethnicity]). In fully adjusted models, residing in counties with high jail incarceration inequity (tertile 3) was associated with higher odds of SMM for Black (odds ratio [OR], 1.14; 95% CI, 1.01-1.29 for NT SMM; OR, 1.20, 95% CI, 1.01-1.42 for SMM), Hispanic or Latinx (OR, 1.24; 95% CI, 1.14-1.34 for NT SMM; OR, 1.20; 95% CI, 1.14-1.27 for SMM), and White (OR, 1.02; 95% CI, 0.93-1.12 for NT SMM; OR, 1.09; 95% CI, 1.02-1.17 for SMM) birthing people, compared with residing in counties with low inequity (tertile 1). Conclusions and Relevance: The findings of this study highlight the adverse maternal health consequences of structural racism manifesting via the criminal-legal system and underscore the need for community-based alternatives to inequitable punitive practices.

Trends and Disparities in Severe Maternal Morbidity Indicator Categories during Childbirth Hospitalization in California from 1997 to 2017.

OBJECTIVE: Severe maternal morbidity (SMM) is increasing and characterized by substantial racial and ethnic disparities. Analyzing trends and disparities across time by etiologic or organ system groups instead of an aggregated index may inform specific, actionable pathways to equitable care. We explored trends and racial and ethnic disparities in seven SMM categories at childbirth hospitalization. STUDY DESIGN: We analyzed California birth cohort data on all live and stillbirths ≥ 20 weeks' gestation from 1997 to 2017 (n = 10,580,096) using the Centers for Disease Control and Prevention's SMM index. Cases were categorized into seven nonmutually exclusive indicator categories (cardiac, renal, respiratory, hemorrhage, sepsis, other obstetric, and other medical SMM). We compared prevalence and trends in SMM indicator categories overall and by racial and ethnic group using logistic and linear regression. RESULTS: SMM occurred in 1.16% of births and nontransfusion SMM in 0.54%. Hemorrhage SMM occurred most frequently (27 per 10,000 births), followed by other obstetric (11), respiratory (7), and sepsis, cardiac, and renal SMM (5). Hemorrhage, renal, respiratory, and sepsis SMM increased over time for all racial and ethnic groups. The largest disparities were for Black individuals, including over 3-fold increased odds of other medical SMM. Renal and sepsis morbidity had the largest relative increases over time (717 and 544%). Sepsis and hemorrhage SMM had the largest absolute changes over time (17 per 10,000 increase). Disparities increased over time for respiratory SMM among Black, U.S.-born Hispanic, and non-U.S.-born Hispanic individuals and for sepsis SMM among Asian or Pacific Islander individuals. Disparities decreased over time for sepsis SMM among Black individuals yet remained substantial. CONCLUSION: Our research further supports the critical need to address SMM and disparities as a significant public health priority in the United States and suggests that examining SMM subgroups may reveal helpful nuance for understanding trends, disparities, and potential needs for intervention. KEY POINTS: · By SMM subgroup, trends and racial and ethnic disparities varied yet Black individuals consistently had highest rates.. · Hemorrhage, renal, respiratory, and sepsis SMM significantly increased over time.. · Disparities increased for respiratory SMM among Black, U.S.-born Hispanic and non-U.S.-born Hispanic individuals and for sepsis SMM among Asian or Pacific Islander individuals..

Assessing the relationship between census tract rurality and severe maternal morbidity in California (1997-2018).

PURPOSE: Recent studies have demonstrated an increased risk of severe maternal morbidity (SMM) for people living in rural versus urban counties. Studies have not considered rurality at the more nuanced subcounty census-tract level. This study assessed the relationship between census-tract-level rurality and SMM for birthing people in California. METHODS: We used linked vital statistics and hospital discharge records for births between 1997 and 2018 in California. SMM was defined by at least 1 of 21 potentially fatal conditions and lifesaving procedures. Rural-Urban Commuting Area codes were used to characterize census tract rurality dichotomously (2-category) and at 4 levels (4-category). Covariates included sociocultural-demographic, pregnancy-related, and neighborhood-level factors. We ran a series of mixed-effects logistic regression models with tract-level clustering, reporting risk ratios and 95% confidence intervals (CIs). We used the STROBE reporting guidelines. FINDINGS: Of 10,091,415 births, 1.1% had SMM. Overall, 94.3% of participants resided in urban/metropolitan and 5.7% in rural tracts (3.9% micropolitan, 0.9% small town, 0.8% rural). In 2-category models, the risk of SMM was 10% higher for birthing people in rural versus urban tracts (95% CI: 6%, 13%). In 4-category models, the risk of SMM was 16% higher in micropolitan versus metropolitan tracts (95% CI: 12%, 21%). CONCLUSION: The observed rurality and SMM relationship was driven by living in a micropolitan versus metropolitan tract. Increased risk may result from resource access inequities within suburban areas. Our findings demonstrate the importance of considering rurality at a subcounty level to understand locality-related inequities in the risk of SMM.

Periconceptional intakes of methyl donors and other micronutrients involved in one-carbon metabolism may further reduce the risk of neural tube defects in offspring: a United States population-based case-control study of women meeting the folic acid recommendations.

BACKGROUND: Neural tube defects (NTDs) still occur among some women who consume 400 µg of folic acid for prevention. It has been hypothesized that intakes of methyl donors and other micronutrients involved in one-carbon metabolism may further protect against NTDs. OBJECTIVES: To investigate whether intakes of vitamin B6, vitamin B12, choline, betaine, methionine, thiamine, riboflavin, and zinc, individually or in combination, were associated with NTD risk reduction in offspring of women meeting the folic acid recommendations. METHODS: Data were from the National Birth Defects Prevention Study (United States population-based, case-control). We restricted deliveries between 1999 and 2011 with daily periconceptional folic acid supplementation or estimated dietary folate equivalents ≥400 µg. NTD cases were live births, stillbirths, or terminations affected by spina bifida, anencephaly, or encephalocele (n = 1227). Controls were live births without a major birth defect (n = 7095). We categorized intake of each micronutrient as higher or lower based on a combination of diet (estimated from a food frequency questionnaire) and periconceptional vitamin supplementation. We estimated NTD associations for higher compared with lower intake of each micronutrient, individually and in combination, expressed as odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age, race/ethnicity, education, and study center. RESULTS: NTD associations with each micronutrient were weak to modest. Greater NTD reductions were observed with concurrent higher-amount intakes of multiple micronutrients. For instance, NTD odds were ∼50% lower among participants with ≥4 micronutrients with higher-amount intakes than among participants with ≤1 micronutrient with higher-amount intake (adjusted OR: 0.53; 95% CI: 0.33, 0.86). The strongest reduction occurred with concurrent higher-amount intakes of vitamin B6, vitamin B12, choline, betaine, and methionine (adjusted OR: 0.26; 95% CI: 0.09, 0.77) compared with ≤1 micronutrient with higher-amount intake. CONCLUSIONS: Our findings support that NTD prevention, in the context of folic acid fortification, could be augmented with intakes of methyl donors and other micronutrients involved in folate metabolism.

Neighborhood gentrification, displacement, and severe maternal morbidity in California.

Gentrification, a racialized and profit-driven process in which historically disinvested neighborhoods experience an influx of development that contributes to the improvement of physical amenities, increasing housing costs, and the dispossession and displacement of existing communities, may influence the risk of severe maternal morbidity (SMM). Leveraging a racially diverse population-based sample of all live hospital births in California between 2006 and 2017, we examined associations between neighborhood-level gentrification and SMM. SMM was defined as having one of 21 procedures and diagnoses, as described in the SMM index developed by Centers for Disease Control and Prevention. We compared three gentrification measures to determine which operationalization best captures aspects of gentrification most salient to SMM: Freeman, Landis 3-D, and Urban Displacement Project Gentrification and Displacement Typology. Descriptive analysis assessed bivariate associations between gentrification and birthing people's characteristics. Overall and race and ethnicity-stratified mixed-effects logistic models assessed associations between gentrification and SMM, adjusting for individual sociodemographic and pregnancy factors while accounting for clustering by census tract. The study sample included 5,256,905 births, with 72,718 cases of SMM (1.4%). The percentage of individuals living in a gentrifying neighborhood ranged from 5.7% to 11.7% across exposure assessment methods. Net of individual and pregnancy-related factors, neighborhood-level gentrification, as measured by the Freeman method, was protective against SMM (OR = 0.89, 95% CI: 0.86-0.93); in comparison, gentrification, as measured by the Gentrification and Displacement Typology, was associated with greater risk of SMM (OR = 1.18, 95% CI: 1.14-1.23). These associations were significant among non-Hispanic White, non-Hispanic Black, and Hispanic individuals. Findings demonstrate that gentrification plays a role in shaping the risk of SMM among birthing people in California. Differences in how gentrification is conceptualized and measured, such as an emphasis on housing affordability compared to a broader characterization of gentrification's multiple aspects, may explain the heterogeneity in the directions of observed associations.

Racial and Ethnic Disparities in Anemia and Severe Maternal Morbidity.

OBJECTIVE: To evaluate antepartum anemia prevalence by race and ethnicity, to assess whether such differences contribute to severe maternal morbidity (SMM), and to estimate the contribution of antepartum anemia to SMM and nontransfusion SMM by race and ethnicity. METHODS: We conducted a population-based cohort study using linked vital record and birth hospitalization data for singleton births at or after 20 weeks of gestation in California from 2011 through 2020. Pregnant patients with hereditary anemias, out-of-hospital births, unlinked records, and missing variables of interest were excluded. Antepartum anemia prevalence and trends were estimated by race and ethnicity. Centers for Disease Control and Prevention criteria were used for SMM and nontransfusion SMM indicators. Multivariable logistic regression modeling was used to estimate risk ratios (RRs) for SMM and nontransfusion SMM by race and ethnicity after sequential adjustment for social determinants, parity, obstetric comorbidities, delivery, and antepartum anemia. Population attributable risk percentages were calculated to assess the contribution of antepartum anemia to SMM and nontransfusion SMM by race and ethnicity. RESULTS: In total, 3,863,594 births in California were included. In 2020, Black pregnant patients had the highest incidence of antepartum anemia (21.5%), followed by Pacific Islander (18.2%), American Indian-Alaska Native (14.1%), multiracial (14.0%), Hispanic (12.6%), Asian (10.6%), and White pregnant patients (9.6%). From 2011 to 2020, the prevalence of anemia increased more than100% among Black patients, and there was a persistent gap in prevalence among Black compared with White patients. Compared with White patients, the adjusted risk for SMM was high among most racial and ethnic groups; adjustment for anemia after sequential modeling for known confounders decreased SMM risk most for Black pregnant patients (approximated RR 1.47, 95% CI 1.42-1.53 to approximated RR 1.27, 95% CI 1.22-1.37). Compared with White patients, the full adjusted nontransfusion SMM risk remained high for most groups except Hispanic and multiracial patients. Within each racial and ethnic group, the population attributable risk percentage for antepartum anemia and SMM was highest for multiracial patients (21.4%, 95% CI 17.5-25.0%), followed by Black (20.9%, 95% CI 18.1-23.4%) and Hispanic (20.9%, 95% CI 19.9-22.1%) patients. The nontransfusion SMM population attributable risk percentages for Asian, Black, and White pregnant patients were less than 8%. CONCLUSION: Antepartum anemia, most prevalent among Black pregnant patients, contributed to disparities in SMM by race and ethnicity. Nearly one in five to six SMM cases among Black, Hispanic, American Indian-Alaska Native, Pacific Islander, and multiracial pregnant patients is attributable in part to antepartum anemia.

Neighborhood Deprivation and Neural Tube Defects.

BACKGROUND: Individual measures of socioeconomic status (SES) have been associated with an increased risk of neural tube defects (NTDs); however, the association between neighborhood SES and NTD risk is unknown. Using data from the National Birth Defects Prevention Study (NBDPS) from 1997 to 2011, we investigated the association between measures of census tract SES and NTD risk. METHODS: The study population included 10,028 controls and 1829 NTD cases. We linked maternal addresses to census tract SES measures and used these measures to calculate the neighborhood deprivation index. We used generalized estimating equations to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) estimating the impact of quartiles of census tract deprivation on NTDs adjusting for maternal race-ethnicity, maternal education, and maternal age at delivery. RESULTS: Quartiles of higher neighborhood deprivation were associated with NTDs when compared with the least deprived quartile (Q2: aOR = 1.2; 95% CI = 1.0, 1.4; Q3: aOR = 1.3, 95% CI = 1.1, 1.5; Q4 (highest): aOR = 1.2; 95% CI = 1.0, 1.4). Results for spina bifida were similar; however, estimates for anencephaly and encephalocele were attenuated. Associations differed by maternal race-ethnicity. CONCLUSIONS: Our findings suggest that residing in a census tract with more socioeconomic deprivation is associated with an increased risk for NTDs, specifically spina bifida.

Is gastroschisis associated with county-level socio-environmental quality during pregnancy?

BACKGROUND: Gastroschisis prevalence more than doubled between 1995 and 2012. While there are individual-level risk factors (e.g., young maternal age, low body mass index), the impact of environmental exposures is not well understood. METHODS: We used the U.S. Environmental Protection Agency's Environmental Quality Index (EQI) as a county-level estimate of cumulative environmental exposures for five domains (air, water, land, sociodemographic, and built) and overall from 2006 to 2010. Adjusted odds ratios (aOR) and 95% confidence interval (CI) were estimated from logistic regression models between EQI tertiles (better environmental quality (reference); mid; poorer) and gastroschisis in the National Birth Defects Prevention Study from births delivered between 2006 and 2011. Our analysis included 594 cases with gastroschisis and 4105 infants without a birth defect (controls). RESULTS: Overall EQI was modestly associated with gastroschisis (aOR [95% CI]: 1.29 [0.98, 1.71]) for maternal residence in counties with poorer environmental quality, compared to the reference (better environmental quality). Within domain-specific indices, only the sociodemographic domain (aOR: 1.51 [0.99, 2.29]) was modestly associated with gastroschisis, when comparing poorer to better environmental quality. CONCLUSIONS: Future work could elucidate pathway(s) by which components of the sociodemographic domain or possibly related psychosocial factors like chronic stress potentially contribute to risk of gastroschisis.

Are individual-level risk factors for gastroschisis modified by neighborhood-level socioeconomic factors?

BACKGROUND: Two strong risk factors for gastroschisis are young maternal age (<20 years) and low/normal pre-pregnancy body mass index (BMI), yet the reasons remain unknown. We explored whether neighborhood-level socioeconomic position (nSEP) during pregnancy modified these associations. METHODS: We analyzed data from 1269 gastroschisis cases and 10,217 controls in the National Birth Defects Prevention Study (1997-2011). To characterize nSEP, we applied the neighborhood deprivation index and used generalized estimating equations to calculate odds ratios and relative excess risk due to interaction. RESULTS: Elevated odds of gastroschisis were consistently associated with young maternal age and low/normal BMI, regardless of nSEP. High-deprivation neighborhoods modified the association with young maternal age. Infants of young mothers in high-deprivation areas had lower odds of gastroschisis (adjusted odds ratio [aOR]: 3.1, 95% confidence interval [CI]: 2.6, 3.8) than young mothers in low-deprivation areas (aOR: 6.6; 95% CI: 4.6, 9.4). Mothers of low/normal BMI had approximately twice the odds of having an infant with gastroschisis compared to mothers with overweight/obese BMI, regardless of nSEP (aOR range: 1.5-2.3). CONCLUSION: Our findings suggest nSEP modified the association between gastroschisis and maternal age, but not BMI. Further research could clarify whether the modification is due to unidentified biologic and/or non-biologic factors.

Oxidative balance scores and neural crest cell-related congenital anomalies.

Oxidative stress and redox imbalance adversely affect embryonic development. We developed two oxidative balance scores (OBS) that include dietary and nondietary exposures. We hypothesized that higher scores (i.e., lower oxidative stress) would be associated with lower risk of neural tube defects, orofacial clefts, conotruncal heart defects, and limb deficiencies. We used data from the National Birth Defects Prevention Study to create a dietary OBS based on intake of 13 nutrients and an overall OBS that included the 13 nutrients and eight additional nondietary factors related to oxidative balance (e.g., smoking). We used logistic regression to examine odds ratios associated with having low or high scores (i.e., <10th or >90th percentiles). Continuous models indicated reduced odds associated with high versus low scores (i.e., comparing odds at the 90th versus 10th percentile values of the distribution) on the overall OBS for cleft lip with or without cleft palate [adjusted odds ratio (aOR) 0.72, 95% confidence interval (CI) 0.63-0.82], longitudinal limb deficiency (aOR 0.73, CI 0.54-0.99), and transverse limb deficiency (aOR 0.74, CI 0.58-0.95); increased odds for anencephaly (aOR 1.40, CI 1.07-1.84); and primarily nonsignificant associations with conotruncal heart defects. Results for the dietary OBS were similar. This study provides some evidence that oxidative stress contributes to congenital anomalies related to neural crest cell development.

Early Postpartum Hospital Encounters among Patients with Genitourinary and Wound Infections during Hospitalization for Birth.

OBJECTIVES: This study aimed to assess the associations between genitourinary and wound infections during the birth hospitalization and early postpartum hospital encounters, and to evaluate clinical risk factors for early postpartum hospital encounters among patients with genitourinary and wound infections during the birth hospitalization. STUDY DESIGN: We conducted a population-based cohort study of births in California during 2016 to 2018 and postpartum hospital encounters. We identified genitourinary and wound infections using diagnosis codes. Our main outcome was early postpartum hospital encounter, defined as a readmission or emergency department (ED) visit within 3 days after discharge from the birth hospitalization. We evaluated the association of genitourinary and wound infections (overall and subtypes) with early postpartum hospital encounter using logistic regression, adjusting for sociodemographic factors and comorbidities and stratified by mode of birth. We then evaluated factors associated with early postpartum hospital encounter among patients with genitourinary and wound infections. RESULTS: Among 1,217,803 birth hospitalizations, 5.5% were complicated by genitourinary and wound infections. Genitourinary or wound infection was associated with an early postpartum hospital encounter among patients with both vaginal births (2.2%; adjusted risk ratio [aRR[: 1.26; 95% confidence interval [CI]: 1.17-1.36) and cesarean births (3.2%; aRR: 1.23; 95% CI: 1.15-1.32). Patients with a cesarean birth and a major puerperal infection or wound infection had the highest risk of an early postpartum hospital encounter (6.4 and 4.3%, respectively). Among patients with genitourinary and wound infections during the birth hospitalization, factors associated with an early postpartum hospital encounter included severe maternal morbidity, major mental health condition, prolonged postpartum hospital stay, and, among cesarean births, postpartum hemorrhage (p-value < 0.05). CONCLUSION: Genitourinary and wound infections during hospitalization for birth may increase risk of a readmission or ED visit within the first few days after discharge, particularly among patients who have a cesarean birth and a major puerperal infection or wound infection. KEY POINTS: · In all, 5.5% of patients giving birth had a genitourinary or wound infection (GWI).. · A total of 2.7% of GWI patients had a hospital encounter within 3 days of discharge after birth.. · Major puerperal infection and wound infection had the highest risk of an early hospital encounter.. · Among GWI patients, several birth complications were associated with an early hospital encounter..

Exome-wide assessment of isolated biliary atresia: A report from the National Birth Defects Prevention Study using child-parent trios and a case-control design to identify novel rare variants.

The etiology of biliary atresia (BA) is unknown, but recent studies suggest a role for rare protein-altering variants (PAVs). Exome sequencing data from the National Birth Defects Prevention Study on 54 child-parent trios, one child-mother duo, and 1513 parents of children with other birth defects were analyzed. Most (91%) cases were isolated BA. We performed (1) a trio-based analysis to identify rare de novo, homozygous, and compound heterozygous PAVs and (2) a case-control analysis using a sequence kernel-based association test to identify genes enriched with rare PAVs. While we replicated previous findings on PKD1L1, our results do not suggest that recurrent de novo PAVs play important roles in BA susceptibility. In fact, our finding in NOTCH2, a disease gene associated with Alagille syndrome, highlights the difficulty in BA diagnosis. Notably, IFRD2 has been implicated in other gastrointestinal conditions and warrants additional study. Overall, our findings strengthen the hypothesis that the etiology of BA is complex.

Neighborhood disinvestment and severe maternal morbidity in the state of California.

BACKGROUND: Social determinants of health, including neighborhood context, may be a key driver of severe maternal morbidity and its related racial and ethnic inequities; however, investigations remain limited. OBJECTIVE: This study aimed to examine the associations between neighborhood socioeconomic characteristics and severe maternal morbidity, as well as whether the associations between neighborhood socioeconomic characteristics and severe maternal morbidity were modified by race and ethnicity. STUDY DESIGN: This study leveraged a California statewide data resource on all hospital births at ≥20 weeks of gestation (1997-2018). Severe maternal morbidity was defined as having at least 1 of 21 diagnoses and procedures (eg, blood transfusion or hysterectomy) as outlined by the Centers for Disease Control and Prevention. Neighborhoods were defined as residential census tracts (n=8022; an average of 1295 births per neighborhood), and the neighborhood deprivation index was a summary measure of 8 census indicators (eg, percentage of poverty, unemployment, and public assistance). Mixed-effects logistic regression models (individuals nested within neighborhoods) were used to compare odds of severe maternal morbidity across quartiles (quartile 1 [the least deprived] to quartile 4 [the most deprived]) of the neighborhood deprivation index before and after adjustments for maternal sociodemographic and pregnancy-related factors and comorbidities. Moreover, cross-product terms were created to determine whether associations were modified by race and ethnicity. RESULTS: Of 10,384,976 births, the prevalence of severe maternal morbidity was 1.2% (N=120,487). In fully adjusted mixed-effects models, the odds of severe maternal morbidity increased with increasing neighborhood deprivation index (odds ratios: quartile 1, reference; quartile 4, 1.23 [95% confidence interval, 1.20-1.26]; quartile 3, 1.13 [95% confidence interval, 1.10-1.16]; quartile 2, 1.06 [95% confidence interval, 1.03-1.08]). The associations were modified by race and ethnicity such that associations (quartile 4 vs quartile 1) were the strongest among individuals in the "other" racial and ethnic category (1.39; 95% confidence interval, 1.03-1.86) and the weakest among Black individuals (1.07; 95% confidence interval, 0.98-1.16). CONCLUSION: Study findings suggest that neighborhood deprivation contributes to an increased risk of severe maternal morbidity. Future research should examine which aspects of neighborhood environments matter most across racial and ethnic groups.

Neighborhood-level Socioeconomic Position During Early Pregnancy and Risk of Gastroschisis.

BACKGROUND: Neighborhood-level socioeconomic position has been shown to influence birth outcomes, including selected birth defects. This study examines the un derstudied association between neighborhood-level socioeconomic position during early pregnancy and the risk of gastroschisis, an abdominal birth defect of increasing prevalence. METHODS: We conducted a case-control study of 1,269 gastroschisis cases and 10,217 controls using data from the National Birth Defects Prevention Study (1997-2011). To characterize neighborhood-level socioeconomic position, we conducted a principal component analysis to construct two indices-Neighborhood Deprivation Index (NDI) and Neighborhood Socioeconomic Position Index (nSEPI). We created neighborhood-level indices using census socioeconomic indicators corresponding to census tracts associated with addresses where mothers lived the longest during the periconceptional period. We used generalized estimating equations to estimate odds ratios (ORs) and 95% confidence intervals (CIs), with multiple imputations for missing data and adjustment for maternal race-ethnicity, household income, education, birth year, and duration of residence. RESULTS: Mothers residing in moderate (NDI Tertile 2 aOR = 1.23; 95% CI = 1.03, 1.48 and nSEPI Tertile 2 aOR = 1.24; 95% CI = 1.04, 1.49) or low socioeconomic neighborhoods (NDI Tertile 3 aOR = 1.28; 95% CI = 1.05, 1.55 and nSEPI Tertile 3 aOR = 1.32, 95% CI = 1.09, 1.61) were more likely to deliver an infant with gastroschisis compared with mothers residing in high socioeconomic neighborhoods. CONCLUSIONS: Our findings suggest that lower neighborhood-level socioeconomic position during early pregnancy is associated with elevated odds of gastroschisis. Additional epidemiologic studies may aid in confirming this finding and evaluating potential mechanisms linking neighborhood-level socioeconomic factors and gastroschisis.

Linked birth cohort files for perinatal health research: California as a model for methodology and implementation.

PURPOSE: Rigorous perinatal epidemiologic research depends on population-based parental and neonatal sociodemographic and clinical data. Here we describe the creation of linked birth cohort files, an enriched data source that combines information from vital records with maternal delivery and infant hospital encounter records. METHODS: Probabilistic linkage techniques were used to link vital records (i.e., birth and fetal death certificates) from the California Department of Public Health with hospital inpatient, ambulatory surgery and emergency department encounter data for mothers and infants from the California Department of Health Care Access and Information. RESULTS: From 2012 to 2018, 95% of live birth records were successfully linked to maternal and newborn hospital records while 85% of fetal death records were linked to a maternal delivery record. Overall, 93% of postnatal hospital encounters of infants (i.e., <1 year old) were matched to a linked record. CONCLUSIONS: The linked birth cohort files is a rich resource opening many possibilities for understanding perinatal health outcomes and opportunities for linkage to longitudinal, social determinant, and environmental data. To optimally use this file for research, analysts should evaluate possible shortcomings or biases of the data sources being linked.

Factors Associated with Transfer Distance from Birth Hospital to Repair Hospital for First Surgical Repair among Infants with Myelomeningocele in California.

OBJECTIVE: The objective of our study was to examine factors associated with distance to care for first surgical repair among infants with myelomeningocele in California. STUDY DESIGN: A total of 677 eligible cases with complete geocoded data were identified for birth years 2006 to 2012 using data from the California Perinatal Quality Care Collaborative linked to hospital and vital records. The median distance from home to birth hospital among eligible infants was 9 miles, and from birth hospital to repair hospital was 15 miles. We limited our analysis to infants who lived close to the birth hospital, creating two study groups to examine transfer distance patterns: "lived close and had a short transfer" (i.e., lived <9 miles from birth hospital and traveled <15 miles from birth hospital to repair hospital; n = 92), and "lived close and had a long transfer" (i.e., lived <9 miles from birth hospital and traveled ≥15 miles from birth hospital to repair hospital; n = 96). Log-binomial regression was used to estimate crude and adjusted risk ratios (aRRs and 95% confidence intervals (CIs). Selected maternal, infant, and birth hospital characteristics were compared between the two groups. RESULTS: We found that low birth weight (aRR = 1.44; 95% CI = 1.04, 1.99) and preterm birth (aRR = 1.41; 95% CI = 1.01, 1.97) were positively associated, whereas initiating prenatal care early in the first trimester was inversely associated (aRR = 0.64; 95% CI = 0.46, 0.89) with transferring a longer distance (≥15 miles) from birth hospital to repair hospital. No significant associations were noted by maternal race-ethnicity, socioeconomic indicators, or the level of hospital care at the birth hospital. CONCLUSION: Our study identified selected infant factors associated with the distance to access surgical care for infants with myelomeningocele who had to transfer from birth hospital to repair hospital. Distance-based barriers to care should be identified and optimized when planning deliveries of at-risk infants in other populations. KEY POINTS: · Low birth weight predicted long hospital transfer distance.. · Preterm birth was associated with transfer distance.. · Prenatal care was associated with transfer distance..

Prepregnancy body mass index and gestational diabetes mellitus across Asian and Pacific Islander subgroups in California.

BACKGROUND: The American College of Obstetricians and Gynecologists recommends early screening for gestational diabetes mellitus among pregnant Asian people with a prepregnancy body mass index ≥23.0 kg/m2, in contrast with the recommended screening at a body mass index ≥25 kg/m2 for other races and ethnicities. However, there is significant heterogeneity within Asian and Pacific Islander populations, and gestational diabetes mellitus and its association with body mass index among Asian and Pacific Islander subgroups may not be uniform across all groups. OBJECTIVE: This study aimed to analyze the association between body mass index and gestational diabetes mellitus among Asian and Pacific Islander subgroups in California, specifically gestational diabetes mellitus rates among those with a body mass index above vs below 23 kg/m2, which is the cutoff point for the designation of being overweight among Asians populations. STUDY DESIGN: Using a linked delivery hospitalization discharge and vital records database, we identified patients who gave birth in California between 2007 and 2017 and who self-reported to be 1 of 13 Asian and Pacific Islander subgroups, which was collected from birth and fetal death certificates. In each subgroup, we evaluated the association between body mass index and gestational diabetes mellitus using multivariable logistic regression models adjusted for age, education, parity, payment method, the trimester in which prenatal care was initiated, and nativity. We fit body mass index nonlinearly with splines and categorized body mass index as being above or below 23 kg/m2. Predicted probabilities of gestational diabetes mellitus with 95% confidence intervals were calculated across body mass index values using the nonlinear regression models. RESULTS: The overall prevalence of gestational diabetes mellitus was 14.3% (83,400/584,032), ranging between 8.4% and 17.1% across subgroups. The highest prevalence was among Indian (17.1%), Filipino (16.7%), and Vietnamese (15.5%) subgroups. In these subgroups, gestational diabetes mellitus was diagnosed in 10% to 13% of those with a body mass index <23.0 kg/m2 and in 22% of those with a body mass index ≥23 kg/m2. Gestational diabetes mellitus was least common among Korean (8.4%), Japanese (9.0%), and Samoan (9.8%) subgroups with a gestational diabetes mellitus rate of 5% to 7% among those with a body mass index <23.0 kg/m2 and in 10% to 15% among those with a body mass index ≥23 kg/m2. Although Samoan patients had the highest rate of obesity, defined as body mass index ≥30 kg/m2 (57.4%), they had the third lowest prevalence of gestational diabetes mellitus. Conversely, Vietnamese patients had the second lowest rate of obesity (2.4%) but the highest rate of gestational diabetes mellitus at a body mass index of ≥23 kg/m2 (22.3%). CONCLUSION: Gestational diabetes mellitus and its association with body mass index varied among Asian subgroups but increased as body mass index increased. Subgroups with the lowest prevalence of obesity trended toward a higher prevalence of gestational diabetes mellitus and those with a higher prevalence of obesity trended toward a lower prevalence of gestational diabetes mellitus.