A multi-state analysis on the effect of deprivation and race on PICU admission and mortality in children receiving Medicaid in United States (2007-2014).

INTRODUCTION: In the United States (US), racial and socioeconomic disparities have been implicated in pediatric intensive care unit (PICU) admissions and outcomes, with higher rates of critical illness in more deprived areas. The degree to which this persists despite insurance coverage is unknown. We investigated whether disparities exist in PICU admission and mortality according to socioeconomic position and race in children receiving Medicaid. METHODS: Using Medicaid data from 2007-2014 from 23 US states, we tested the association between area level deprivation and race on PICU admission (among hospitalized children) and mortality (among PICU admissions). Race was categorized as Black, White, other and missing. Patient-level ZIP Code was used to generate a multicomponent variable describing area-level social vulnerability index (SVI). Race and SVI were simultaneously tested for associations with PICU admission and mortality. RESULTS: The cohort contained 8,914,347 children (23·0% Black). There was no clear trend in odds of PICU admission by SVI; however, children residing in the most vulnerable quartile had increased PICU mortality (aOR 1·12 (95%CI 1·04-1·20; p = 0·0021). Black children had higher odds of PICU admission (aOR 1·04; 95% CI 1·03-1·05; p < 0·0001) and higher mortality (aOR 1·09; 95% CI 1·02-1·16; p = 0·0109) relative to White children. Substantial state-level variation was apparent, with the odds of mortality in Black children varying from 0·62 to 1·8. CONCLUSION: In a Medicaid cohort from 2007-2014, children with greater socioeconomic vulnerability had increased odds of PICU mortality. Black children were at increased risk of PICU admission and mortality, with substantial state-level variation. Our work highlights the persistence of sociodemographic disparities in outcomes even among insured children.

County-level Structural Vulnerabilities in Maternal Health and Geographic Variation in Infant Mortality.

OBJECTIVE: To evaluate whether community factors that differentially affect the health of pregnant people contribute to geographic differences in infant mortality across the United States. STUDY DESIGN: This retrospective cohort study sought to characterize the association of a novel composite measure of county-level maternal structural vulnerabilities, the Maternal Vulnerability Index (MVI), with risk of infant death. We evaluated 11,456,232 singleton infants born at 22 0/7 through 44 6/7 weeks' gestation from 2012 to 2014. Using county-level MVI, which ranges from 0-100, multivariable mixed effects logistic regression models quantified associations per 20-point increment in MVI, with odds of death clustered at the county level and adjusted for state, maternal, and infant covariates. Secondary analyses stratified by the social, physical, and health exposures that comprise the overall MVI score. Outcome was also stratified by cause of death. RESULTS: Odds of death were higher among infants from counties with the greatest maternal vulnerability (0.62% in highest quintile vs 0.32% in lowest quintile, [p<0.001]). Odds of death increased 6% per 20-point increment in MVI (aOR: 1.06, 95% CI 1.04, 1.07). The effect estimate was highest with theme of mental health and substance use (aOR 1.08; 95% CI 1.06, 1.09). Increasing vulnerability was associated with six of seven causes of death. CONCLUSIONS: Community-level social, physical, and healthcare determinants indicative of maternal vulnerability may explain some of the geographic variation in infant death, regardless of cause of death. Interventions targeted to county-specific maternal vulnerabilities may reduce infant mortality.

The Association of NICU Strain with Neonatal Mortality and Morbidity.

Objective: To examine the association of admission NICU strain with neonatal mortality and morbidity. Study Design: 2008-2021 South Carolina cohort using linked vital statistics and discharge data of 22-44 weeks GA infants, born at hospitals with ≥ level 2 unit and ≥5 births of infants <34 weeks GA/year. The exposure was tertiles of admission NICU strain, defined as the sum of infants <44 weeks GA with a congenital anomaly plus all infants born <33 weeks GA at midnight on the day of birth. We used Poisson generalized linear mixed models to examine the association of exposure to strain with the primary outcome of a composite of mortality and term and preterm morbidities adjusting for patient and hospital characteristics. Results: We studied 64,647 infants from 30 hospitals. High strain was associated with increased risk of mortality and morbidity adjusting for patient/hospital factors (aIRR 1.07, 95% CI 1.01 - 1.12). Conclusion: NICU strain is associated with increased adverse outcomes.

Racial and ethnic disparities in severe maternal morbidity from pregnancy through 1-year postpartum.

BACKGROUND: Previous studies examining racial and ethnic disparities in severe maternal morbidity (SMM) have mainly focused on intrapartum hospitalization. There is limited information regarding the racial and ethnic distribution of SMM occurring in the antepartum and postpartum periods, including SMM occurring beyond the traditional 6 weeks postpartum period. OBJECTIVE: To examine the racial and ethnic distribution of SMM during antepartum, intrapartum, and postpartum hospitalizations through 1-year postpartum, overall and stratified by maternal sociodemographic factors, and to estimate the percent increase in SMM by race and ethnicity and maternal sociodemographic factors within each racial and ethnic group after accounting for both antepartum and postpartum SMM through 1-year postpartum rather than just SMM occurring during the intrapartum hospitalization. STUDY DESIGN: We conducted a retrospective cohort study using birth and fetal death certificate data linked to hospital discharge records from Michigan, Oregon, and South Carolina from 2008-2020. We examined the distribution of non-transfusion SMM and total SMM per 10,000 cases during antepartum, intrapartum, and postpartum hospitalizations through 365 days postpartum by race and ethnicity and by maternal education and insurance type within each racial and ethnic group. We subsequently examined "SMM cases added" by race and ethnicity and by maternal education and insurance type within each racial and ethnic group. The "SMM cases added" represent cases among unique individuals that are identified by considering the antepartum and postpartum periods but that would be missed if only the intrapartum hospitalization cases were included. RESULTS: Among 2,584,206 birthing individuals, a total of 37,112 (1.4%) individuals experienced non-transfusion SMM and 64,661 (2.5%) experienced any SMM during antepartum, intrapartum, and/or postpartum hospitalization. Black individuals had the highest rate of antepartum, intrapartum, and postpartum non-transfusion and total SMM followed by American Indian individuals. Asian individuals had the lowest rate of non-transfusion and total SMM during antepartum and postpartum hospitalizations while White individuals had the lowest rate of non-transfusion and total SMM during the intrapartum hospitalization. Black individuals were 1.9 times more likely to experience non-transfusion SMM during the intrapartum hospitalization than White individuals, which increased to 2.8 times during the antepartum period and to 2.5 times during the postpartum period. Asian and Hispanic individuals were less likely to experience SMM in the postpartum period than White individuals. Including antepartum and postpartum hospitalizations resulted in disproportionately more cases among Black and American Indian individuals than among White, Hispanic, and Asian individuals. The additional cases were also more likely to occur among individuals with lower educational levels and individuals on government insurance. CONCLUSION: Racial disparities in SMM are underreported in estimates that focus on the intrapartum hospitalization. Additionally, individuals with low socio-economic status bear the greatest burden of SMM occurring during the antepartum and postpartum periods. Approaches that focus on mitigating SMM during the intrapartum period only do not address the full spectrum of health disparities. El resumen está disponible en Español al final del artículo.

Who's in the NICU? A population-level analysis.

OBJECTIVE: To understand the characteristics of infants admitted to US NICUs. STUDY DESIGN: 2006-2014 linked birth certificate and hospital discharge data for potentially viable deliveries in Pennsylvania and South Carolina were used. NICU admissions were identified using revenue codes. NICU-admitted infants were categorized by gestational age (GA), birthweight, and condition severity (for GA 35+ weeks). We also assessed total patient days and trends over time. RESULTS: 12% of infants were admitted to a NICU; 13.6% were GA < 32 weeks (45.3% of total days); 36.1% were GA 32-36 weeks (31.2% of total days); and 50.4% were GA 37+ weeks (23.5% of total days). 20% of admissions were for infants with GA 35+ weeks and mild conditions. Admissions increased numerically from 11.2% (2006) to 13.0% (2014), with increases among infants 35+ weeks. CONCLUSION: Most NICU admissions are for infants 35+ weeks GA, many with mild conditions who may be accommodated in well-baby units.

Severe maternal morbidity from pregnancy through 1 year postpartum.

BACKGROUND: Few recent studies have examined the rate of severe maternal morbidity occurring during the antenatal and/or postpartum period to 42 days after delivery. However, little is known about the rate of severe maternal morbidity occurring beyond 42 days after delivery. OBJECTIVE: This study aimed to examine the distribution of severe maternal morbidity and its indicators during antenatal, delivery, and postpartum hospitalizations to 365 days after delivery and to estimate the increase in severe maternal morbidity rate and its indicators after accounting for antenatal and postpartum severe maternal morbidity to 365 days after delivery. STUDY DESIGN: This was a retrospective cohort study using birth and fetal death certificate data linked to hospital discharge records from Michigan, Oregon, and South Carolina from 2008 to 2020. This study examined the distribution of severe maternal morbidity, nontransfusion severe maternal morbidity, and severe maternal morbidity indicators during antenatal, delivery, and postpartum hospitalizations to 365 days after delivery. Subsequently, this study examined "severe maternal morbidity cases added," which represent cases among unique individuals that are included by considering the antenatal and postpartum periods but that would be missed if only the delivery hospitalization cases were included. RESULTS: A total of 64,661 (2.5%) individuals experienced severe maternal morbidity, whereas 37,112 (1.4%) individuals experienced nontransfusion severe maternal morbidity during antenatal, delivery, and/or postpartum hospitalization. A total of 31% of severe maternal morbidity cases were added after accounting for severe maternal morbidity occurring during the antenatal or postpartum hospitalization to 365 days after delivery, whereas 49% of nontransfusion severe maternal morbidity cases were added after accounting for nontransfusion severe maternal morbidity occurring during the antenatal or postpartum periods. Severe maternal morbidity occurring between 43 and 365 days after delivery contributed to 12% of all severe maternal morbidity cases, whereas nontransfusion severe maternal morbidity occurring between 43 and 365 days after delivery contributed to 19% of all nontransfusion severe maternal morbidity cases. CONCLUSION: Our study showed that a total of 31% of severe maternal morbidity and 49% of nontransfusion severe maternal morbidity cases were added after accounting for severe maternal morbidity occurring during the antenatal or postpartum hospitalization to 365 days after delivery. Our findings highlight the importance of expanding the severe maternal morbidity definition beyond the delivery hospitalization to better capture the full period of increased risk, identify contributing factors, and design strategies to mitigate this risk. Only then can we improve outcomes for mothers and subsequently the quality of life of their infants.

The impact of volume and neonatal level of care on outcomes of moderate and late preterm infants.

OBJECTIVE: Evaluate the relationship of neonatal unit level of care (LOC) and volume with mortality or morbidity in moderate-late preterm (MLP) (32-36 weeks' gestation) infants. DESIGN: Retrospective cohort study of 650,865 inborn MLP infants in 4976 hospitals-years using 2003-2015 linked administrative data from 4 states. Exposure was combined neonatal LOC and MLP annual volume. The primary outcome was death or morbidity (respiratory distress syndrome, severe intraventricular hemorrhage, necrotizing enterocolitis, sepsis, infection, pneumothorax, extreme length of stay) with components as secondary outcomes. Poisson regression models adjusted for patient characteristics with a random effect for unit were used. RESULTS: In adjusted models, high-volume level 2 units had a lower risk of the primary outcome compared to low-volume level 3 units (aIRR 0.90 [95% CI 0.83-0.98] vs. aIRR 1.13 [95% CI 1.03-1.24], p < 0.001) CONCLUSION: MLP infants had improved outcomes in high-volume level 2 units compared to low-volume level 3 units in adjusted analysis.

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.

The association of maternal country/region of origin and nativity with infant mortality rate among Hispanic preterm infants.

OBJECTIVES: Among US-born preterm infants of Hispanic mothers, we analyzed the unadjusted and adjusted infant mortality rate (IMR) by country/region of origin and maternal nativity status. STUDY DESIGN: Using linked national US birth and death certificate data (2005-2014), we examined preterm infants of Hispanic mothers by subgroup and nativity. Clinical and sociodemographic covariates were included and the main outcome was death in the first year of life. RESULTS: In our cohort of 891,216 preterm Hispanic infants, we demonstrated different rates of infant mortality by country and region of origin, but no difference between infants of Hispanic mothers who were US vs. foreign-born. CONCLUSION: These findings highlight the need to disaggregate the heterogenous Hispanic birthing population into regional and national origin groups to better understand unique factors associated with adverse perinatal outcomes in order to develop more targeted interventions for these subgroups.

Association between stillbirth and severe maternal morbidity.

BACKGROUND: Severe maternal morbidity has been increasing in the past few decades. Few studies have examined the risk of severe maternal morbidity among individuals with stillbirths vs individuals with live-birth deliveries. OBJECTIVE: This study aimed to examine the prevalence and risk of severe maternal morbidity among individuals with stillbirths vs individuals with live-birth deliveries during delivery hospitalization as a primary outcome and during the postpartum period as a secondary outcome. STUDY DESIGN: This was a retrospective cohort study using birth and fetal death certificate data linked to hospital discharge records from California (2008-2018), Michigan (2008-2020), Missouri (2008-2014), Pennsylvania (2008-2014), and South Carolina (2008-2020). Relative risk regression analysis was used to examine the crude and adjusted relative risks of severe maternal morbidity along with 95% confidence intervals among individuals with stillbirths vs individuals with live-birth deliveries, adjusting for birth year, state of residence, maternal sociodemographic characteristics, and the obstetric comorbidity index. RESULTS: Of the 8,694,912 deliveries, 35,012 (0.40%) were stillbirths. Compared with individuals with live-birth deliveries, those with stillbirths were more likely to be non-Hispanic Black (10.8% vs 20.5%); have Medicaid (46.5% vs 52.0%); have pregnancy complications, including preexisting diabetes mellitus (1.1% vs 4.3%), preexisting hypertension (2.3% vs 6.2%), and preeclampsia (4.4% vs 8.4%); have multiple pregnancies (1.6% vs 6.2%); and reside in South Carolina (7.4% vs 11.6%). During delivery hospitalization, the prevalence rates of severe maternal morbidity were 791 cases per 10,000 deliveries for stillbirths and 154 cases per 10,000 deliveries for live-birth deliveries, whereas the prevalence rates for nontransfusion severe maternal morbidity were 502 cases per 10,000 deliveries for stillbirths and 68 cases per 10,000 deliveries for live-birth deliveries. The crude relative risk for severe maternal morbidity was 5.1 (95% confidence interval, 4.9-5.3), whereas the adjusted relative risk was 1.6 (95% confidence interval, 1.5-1.8). For nontransfusion severe maternal morbidity among stillbirths vs live-birth deliveries, the crude relative risk was 7.4 (95% confidence interval, 7.0-7.7), whereas the adjusted relative risk was 2.0 (95% confidence interval, 1.8-2.3). This risk was not only elevated among individuals with stillbirth during the delivery hospitalization but also through 1 year after delivery (severe maternal morbidity adjusted relative risk, 1.3; 95% confidence interval, 1.1-1.4; nontransfusion severe maternal morbidity adjusted relative risk, 1.2; 95% confidence interval, 1.1-1.3). CONCLUSION: Stillbirth was found to be an important contributor to severe maternal morbidity.

Inter-hospital Variation in COVID-19 Era Pediatric Hospitalizations by Age Group and Diagnosis.

BACKGROUND: Mitigation strategies and public responses to coronavirus disease 2019 (COVID-19) varied geographically and may have differentially affected burden of pediatric disease and hospitalization practices. We aimed to quantify hospital-specific variation in hospitalizations during the COVID-19 era. METHODS: Using Pediatric Health Information Systems data from 44 Children's Hospitals, this retrospective multicenter analysis compared hospitalizations of children (1 day-17 years) from the COVID-19 era (March 1, 2020-June 30, 2021) to prepandemic (January 1, 2017-December 31, 2019). Variation in the magnitude of hospital-specific decline between eras was determined using coefficients of variation (CV). Spearman's test was used to assess correlation of variation with community and hospital factors. RESULTS: The COVID-19 era decline in hospitalizations varied between hospitals (CV 0.41) and was moderately correlated with declines in respiratory infection hospitalizations (r = 0.69, P < .001). There was no correlation with community or hospital factors. COVID-19 era changes in hospitalizations for mental health conditions varied widely between centers (CV 2.58). Overall, 22.7% of hospitals saw increased admissions for adolescents, and 29.5% saw increases for newborns 1 to 14 days, representing significant center-specific variation (CV 2.30 for adolescents and 1.98 for newborns). CONCLUSIONS: Pandemic-era change in hospitalizations varied across institutions, partially because of hospital-specific changes in respiratory infections. Residual variation exists for mental health conditions and in groups least likely to be admitted for respiratory infections, suggesting that noninfectious conditions may be differentially and uniquely affected by local policies and hospital-specific practices enacted during the COVID-19 era.

Perinatal Care Measures Are Incomplete If They Do Not Assess The Birth Parent-Infant Dyad As A Whole.

Measures of perinatal care quality and outcomes often focus on either the birth parent or the infant. We used linked vital statistics and hospital discharge data to describe a dyadic measure (including both the birth parent and the infant) for perinatal care during the birth hospitalization. In this five-state cohort of 2010-18 births, 21.6 percent of birth parent-infant dyads experienced at least one complication, and 9.6 percent experienced a severe complication. Severe infant complications were eight times more prevalent than severe birth parent complications. Among birth parents with a severe complication, the co-occurrence of a severe infant complication ranged from 2 percent to 51 percent, whereas among infants with a severe complication, the co-occurrence of a severe birth parent complication was rare, ranging from 0.04 percent to 5 percent. These data suggest that measures, clinical interventions, public reporting, and policies focused on either the birth parent or the infant are incomplete in their assessment of a healthy dyad. Thus, clinicians, administrators, and policy makers should evaluate dyadic measures, incentivize positive outcomes for both patients (parent and infant), and create policies that support the health of the dyad.

Chronic Hypertension in Pregnancy and Racial-Ethnic Disparities in Complications.

OBJECTIVE: To evaluate whether there are individual- and population-level associations between chronic hypertension and pregnancy complications, and to assess differences across seven racial-ethnic groups. METHODS: This population-based study used linked vital statistics and hospitalization discharge data from all live and stillbirths in California (2008-2018), Michigan (2008-2020), Oregon (2008-2020), Pennsylvania (2008-2014), and South Carolina (2008-2020). We used multivariable log-binomial regression models to estimate risk ratios (RRs) and population attributable risk (PAR) percentages with 95% CIs for associations between chronic hypertension and several obstetric and neonatal outcomes, selected based on prior evidence and pathologic pathways. We adjusted models for demographic factors (race and ethnicity, payment method, educational attainment), age, body mass index, obstetric history, delivery year, and state, and conducted analyses stratified across seven racial-ethnic groups. RESULTS: The study included 7,955,713 pregnancies, of which 168,972 (2.1%) were complicated by chronic hypertension. Chronic hypertension was associated with several adverse obstetric and neonatal outcomes, with the largest adjusted PAR percentages observed for preeclampsia with severe features or eclampsia (22.4; 95% CI 22.2-22.6), acute renal failure (13.6; 95% CI 12.6-14.6), and pulmonary edema (10.7; 95% CI 8.9-12.6). Estimated RRs overall were similar across racial-ethnic groups, but PAR percentages varied. The adjusted PAR percentages (95% CI) for severe maternal morbidity-a widely used composite of acute severe events-for people who were American Indian or Alaska Native, Asian, Black, Latino, Native Hawaiian or Other Pacific Islander, White, and Multiracial or Other were 5.0 (1.1-8.8), 3.7 (3.0-4.3), 9.0 (8.2-9.8), 3.9 (3.6-4.3), 11.6 (6.4-16.5), 3.2 (2.9-3.5), and 5.5 (4.2-6.9), respectively. CONCLUSION: Chronic hypertension accounts for a substantial fraction of obstetric and neonatal morbidity and contributes to higher complication rates, particularly for people who are Black or Native Hawaiian or Other Pacific Islander.

Obstetric Volume and Severe Maternal Morbidity Among Low-Risk and Higher-Risk Patients Giving Birth at Rural and Urban US Hospitals.

Importance: Identifying hospital factors associated with severe maternal morbidity (SMM) is essential to clinical and policy efforts. Objective: To assess associations between obstetric volume and SMM in rural and urban hospitals and examine whether these associations differ for low-risk and higher-risk patients. Design, Setting, and Participants: This retrospective cross-sectional study of linked vital statistics and patient discharge data was conducted from 2022 to 2023. Live births and stillbirths (≥20 weeks' gestation) at hospitals in California (2004-2018), Michigan (2004-2020), Pennsylvania (2004-2014), and South Carolina (2004-2020) were included. Data were analyzed from December 2022 to May 2023. Exposures: Annual birth volume categories (low, medium, medium-high, and high) for hospitals in urban (10-500, 501-1000, 1001-2000, and >2000) and rural (10-110, 111-240, 241-460, and >460) counties. Main Outcome and Measures: The main outcome was SMM (excluding blood transfusion); covariates included age, payer status, educational attainment, race and ethnicity, and obstetric comorbidities. Analyses were stratified for low-risk and higher-risk obstetric patients based on presence of at least 1 clinical comorbidity. Results: Among more than 11 million urban births and 519 953 rural births, rates of SMM ranged from 0.73% to 0.50% across urban hospital volume categories (high to low) and from 0.47% to 0.70% across rural hospital volume categories (high to low). Risk of SMM was elevated for patients who gave birth at rural hospitals with annual birth volume of 10 to 110 (adjusted risk ratio [ARR], 1.65; 95% CI, 1.14-2.39), 111 to 240 (ARR, 1.37; 95% CI, 1.10-1.70), and 241 to 460 (ARR, 1.26; 95% CI, 1.05-1.51), compared with rural hospitals with greater than 460 births. Increased risk of SMM occurred for low-risk and higher-risk obstetric patients who delivered at rural hospitals with lower birth volumes, with low-risk rural patients having notable discrepancies in SMM risk between low (ARR, 2.32; 95% CI, 1.32-4.07), medium (ARR, 1.66; 95% CI, 1.20-2.28), and medium-high (ARR, 1.68; 95% CI, 1.29-2.18) volume hospitals compared with high volume (>460 births) rural hospitals. Among hospitals in urban counties, there was no significant association between birth volume and SMM for low-risk or higher-risk obstetric patients. Conclusions and Relevance: In this cross-sectional study of births in US rural and urban counties, risk of SMM was elevated for low-risk and higher-risk obstetric patients who gave birth in lower-volume hospitals in rural counties, compared with similar patients who gave birth at rural hospitals with greater than 460 annual births. These findings imply a need for tailored quality improvement strategies for lower volume hospitals in rural communities.

Association of Sickle Cell Disease With Racial Disparities and Severe Maternal Morbidities in Black Individuals.

Importance: Little is known about the association between sickle cell disease (SCD) and severe maternal morbidity (SMM). Objective: To examine the association of SCD with racial disparities in SMM and with SMM among Black individuals. Design, Setting, and Participants: This cohort study was a retrospective population-based investigation of individuals with and without SCD in 5 states (California [2008-2018], Michigan [2008-2020], Missouri [2008-2014], Pennsylvania [2008-2014], and South Carolina [2008-2020]) delivering a fetal death or live birth. Data were analyzed between July and December 2022. Exposure: Sickle cell disease identified during the delivery admission by using International Classification of Diseases, Ninth Revision and Tenth Revision codes. Main Outcomes and Measures: The primary outcomes were SMM including and excluding blood transfusions during the delivery hospitalization. Modified Poisson regression was used to estimate risk ratios (RRs) adjusted for birth year, state, insurance type, education, maternal age, Adequacy of Prenatal Care Utilization Index, and obstetric comorbidity index. Results: From a sample of 8 693 616 patients (mean [SD] age, 28.5 [6.1] years), 956 951 were Black individuals (11.0%), of whom 3586 (0.37%) had SCD. Black individuals with SCD vs Black individuals without SCD were more likely to have Medicaid insurance (70.2% vs 64.6%), to have a cesarean delivery (44.6% vs 34.0%), and to reside in South Carolina (25.2% vs 21.5%). Sickle cell disease accounted for 8.9% and for 14.3% of the Black-White disparity in SMM and nontransfusion SMM, respectively. Among Black individuals, SCD complicated 0.37% of the pregnancies but contributed to 4.3% of the SMM cases and to 6.9% of the nontransfusion SMM cases. Among Black individuals with SCD compared with those without, the crude RRs of SMM and nontransfusion SMM during the delivery hospitalization were 11.9 (95% CI, 11.3-12.5) and 19.8 (95% CI, 18.5-21.2), respectively, while the adjusted RRs were 3.8 (95% CI, 3.3-4.5) and 6.5 (95% CI, 5.3-8.0), respectively. The SMM indicators that incurred the highest adjusted RRs included air and thrombotic embolism (4.8; 95% CI, 2.9-7.8), puerperal cerebrovascular disorders (4.7; 95% CI, 3.0-7.4), and blood transfusion (3.7; 95% CI, 3.2-4.3). Conclusions and Relevance: In this retrospective cohort study, SCD was found to be an important contributor to racial disparities in SMM and was associated with an elevated risk of SMM among Black individuals. Efforts from the research community, policy makers, and funding agencies are needed to advance care among individuals with SCD.

County-Level Maternal Vulnerability and Preterm Birth in the US.

Importance: Appreciation for the effects of neighborhood conditions and community factors on perinatal health is increasing. However, community-level indices specific to maternal health and associations with preterm birth (PTB) have not been assessed. Objective: To examine the association of the Maternal Vulnerability Index (MVI), a novel county-level index designed to quantify maternal vulnerability to adverse health outcomes, with PTB. Design, Setting, and Participants: This retrospective cohort study used US Vital Statistics data from January 1 to December 31, 2018. Participants included 3 659 099 singleton births at 22 plus 0/7 to 44 plus 6/7 weeks of gestation born in the US. Analyses were conducted from December 1, 2021, through March 31, 2023. Exposure: The MVI, a composite measure of 43 area-level indicators, categorized into 6 themes reflecting physical, social, and health care landscapes. Overall MVI and theme were stratified by quintile (very low to very high) by maternal county of residence. Main Outcomes and Measures: The primary outcome was PTB (gestational age <37 weeks). Secondary outcomes were PTB categories: extreme (gestational age ≤28 weeks), very (gestational age 29-31 weeks), moderate (gestational age 32-33 weeks), and late (gestational age 34-36 weeks). Multivariable logistic regression quantified associations of MVI, overall and by theme, with PTB, overall and by PTB category. Results: Among 3 659 099 births, 298 847 (8.2%) were preterm (male, 51.1%; female, 48.9%). Maternal race and ethnicity included 0.8% American Indian or Alaska Native, 6.8% Asian or Pacific Islander, 23.6% Hispanic, 14.5% non-Hispanic Black, 52.1% non-Hispanic White, and 2.2% with more than 1 race. Compared with full-term births, MVI was higher for PTBs across all themes. Very high MVI was associated with increased PTB in unadjusted (odds ratio [OR], 1.50 [95% CI, 1.45-1.56]) and adjusted (OR, 1.07 [95% CI, 1.01-1.13]) analyses. In adjusted analyses of PTB categories, MVI had the largest association with extreme PTB (adjusted OR, 1.18 [95% CI, 1.07-1.29]). Higher MVI in the themes of physical health, mental health and substance abuse, and general health care remained associated with PTB overall in adjusted models. While the physical health and socioeconomic determinant themes were associated with extreme PTB, physical health, mental health and substance abuse, and general health care themes were associated with late PTB. Conclusions and Relevance: The findings of this cohort study suggest that MVI was associated with PTB even after adjustment for individual-level confounders. The MVI is a useful measure for county-level PTB risk that may have policy implications for counties working to lower preterm rates and improve perinatal outcomes.

Racial and Ethnic Disparities in Sudden Unexpected Infant Death Among US Infants Born Preterm.

OBJECTIVE: To investigate among US infants born at <37 weeks gestation (a) racial and ethnic disparities in sudden unexpected infant death (SUID) and (b) state variation in SUID rates and non-Hispanic Black (NHB)-non-Hispanic White (NHW) SUID disparity ratio. METHODS: In this retrospective cohort analysis of linked birth and death certificates from 50 states from 2005 to 2014, SUID was defined by the following International Classification of Diseases, 9th or 10th edition, codes listed on death certificates: (7980, R95 or Recode 135; ASSB: E913, W75 or Recode 146; Unknown: 7999 R99 or Recode 134). Multivariable models were used to assess the independent association between maternal race and ethnicity and SUID, adjusting for several maternal and infant characteristics. The NHB-NHW SUID disparity ratios were calculated for each state. RESULTS: Among 4 086 504 preterm infants born during the study period, 8096 infants (0.2% or 2.0 per 1000 live births) experienced SUID. State variation in SUID ranged from the lowest rate of 0.82 per 1000 live births in Vermont to the highest rate of 3.87 per 1000 live births in Mississippi. Unadjusted SUID rates across racial and ethnic groups varied from 0.69 (Asian/Pacific Islander) to 3.51 (NHB) per 1000 live births. In the adjusted analysis, compared with NHW infants, NHB and Alaska Native/American Indian preterm infants had greater odds of SUID (aOR, 1.5;[95% CI, 1.42-1.59] and aOR, 1.44 [95% CI, 1.21-1.72]) with varying magnitude of SUID rates and NHB-NHW disparities across states. CONCLUSIONS: Significant racial and ethnic disparities in SUID among preterm infants exist with variation across US states. Additional research to identify the drivers of these disparities within and across states is needed.

Changes in prenatal testing during the COVID-19 pandemic.

Objective: The coronavirus disease 2019 (COVID-19) pandemic disrupted healthcare delivery, including prenatal care. The study objective was to assess if timing of routine prenatal testing changed during the COVID-19 pandemic. Methods: Retrospective observational cohort study using claims data from a regional insurer (Highmark) and electronic health record data from two academic health systems (Penn Medicine and Yale New Haven) to compare prenatal testing timing in the pre-pandemic (03/10/2018-12/31/2018 and 03/10/2019-12/31/2019) and early COVID-19 pandemic (03/10/2020-12/31/2020) periods. Primary outcomes were second trimester fetal anatomy ultrasounds and gestational diabetes (GDM) testing. A secondary analysis examined first trimester ultrasounds. Results: The three datasets included 31,474 pregnant patients. Mean gestational age for second trimester anatomy ultrasounds increased from the pre-pandemic to COVID-19 period (Highmark 19.4 vs. 19.6 weeks; Penn: 20.1 vs. 20.4 weeks; Yale: 18.8 vs. 19.2 weeks, all p < 0.001). There was a detectable decrease in the proportion of patients who completed the anatomy survey <20 weeks' gestation across datasets, which did not persist at <23 weeks' gestation. There were no consistent changes in timing of GDM screening. There were significant reductions in the proportion of patients with first trimester ultrasounds in the academic institutions (Penn: 57.7% vs. 40.6% and Yale: 78.7% vs. 65.5%, both p < 0.001) but not Highmark. Findings were similar with multivariable adjustment. Conclusion: While some prenatal testing happened later in pregnancy during the pandemic, pregnant patients continued to receive appropriately timed testing. Despite disruptions in care delivery, prenatal screening remained a priority for patients and providers during the COVID-19 pandemic.

Perinatal outcomes for rural obstetric patients and neonates in rural-located and metropolitan-located hospitals.

OBJECTIVE: To compare rural obstetric patient and neonate characteristics and outcomes by birth location. METHODS: Retrospective observational cohort study of rural residents' hospital births from California, Pennsylvania, and South Carolina. Hospitals in rural counties were rural-located, those in metropolitan counties with ≥10% of obstetric patients from rural communities were rural-serving, metropolitan-located, others were non-rural-serving, metropolitan-located. Any adverse obstetric patient or neonatal outcomes were assessed with logistic regression accounting for patient characteristics, state, year, and hospital. RESULTS: Of 466,896 rural patient births, 64.3% occurred in rural-located, 22.5% in rural-serving, metropolitan-located, and 13.1% in non-rural-serving, metropolitan-located hospitals. The odds of any adverse outcome increased in rural-serving (aOR 1.27, 95% CI 1.10-1.46) and non-rural-serving (aOR 1.35, 95% CI 1.18-1.55) metropolitan-located hospitals. CONCLUSION: One-third of rural obstetric patients received care in metropolitan-located hospitals. These patients have higher comorbidity rates and higher odds of adverse outcomes likely reflecting referral for higher baseline illness severity.