Black-White disparities in maternal vulnerability and adverse pregnancy outcomes: an ecological population study in the United States, 2014–2018

Abstract

Systematic information on the association between community-level determinants and maternal health outcomes and disparities is needed. We aimed to investigate multi-dimensional place-based contributions to Black-White maternal health disparities in the United States. We constructed the Maternal Vulnerability Index, a geospatial measure of vulnerability to poor maternal health. The index was linked to 13m live births and maternal deaths to mothers aged 10-44 for 2014-2018 in the United States. We quantified racial disparities in exposure to higher risk environments, and used logistic regression to estimate associations between race, vulnerability, and maternal death (n=3633), low birthweight (n=1.1m), and preterm birth (n=1.3m). Black mothers lived in disproportionately higher maternal vulnerability counties, when compared to White mothers (median of 55 vs 36/100 points). Giving birth in the highest-quartile MVI counties was associated with an increase in the odds of poor outcomes when compared to the lowest-quartile (aOR 1.43 [95% CI 1.20-1.71] for mortality, 1.39 [1.37-1.41] for low birthweight and 1.41 [1.39-1.43] for preterm birth, adjusted for age, educational attainment level and race/ethnicity). Racial disparities exist in low- and high-vulnerability counties: Black mothers in the least vulnerable counties remain at higher risk of maternal mortality, preterm birth, and low birthweight as White mothers in the most vulnerable. Exposure to community maternal vulnerability is associated with increased odds of adverse outcomes, but the Black-White gap in outcomes remained under all vulnerability levels. Our findings suggest that locally-informed precision health interventions and further research into racism are needed to achieve maternal health equity. Bill & Melinda Gates Foundation(grant number INV-024583).