Intersectional Disparities in Severe Maternal Morbidity Across the Perinatal Continuum: A Population-Based Analysis

This study aimed to estimate the risk of severe maternal morbidity (SMM) by race/ethnicity and physical disability status across the perinatal continuum using an intersectional framework.

We conducted a retrospective cohort study of 1 327 862 singleton births in Massachusetts (1999-2019) using the Pregnancy to Early Life Longitudinal Data System. SMM was identified using the 20 indicators defined by the Centers for Disease Control and Prevention, with a secondary analysis including transfusion. We examined 3 mutually exclusive time periods: prenatal (non-delivery prenatal hospitalizations), delivery, and postpartum (≤365 days after delivery discharge). Modified Poisson regression models estimated unadjusted and adjusted relative risks of SMM by race/ethnicity and physical disability status, with non-disabled White birthing persons serving as the reference. Additive interaction was assessed using the relative excess risk due to interaction and the attributable proportion.

SMM rates were 10.1 per 10 000 prenatal hospitalizations, 43.2 per 10 000 delivery hospitalizations, and 14.3 per 10 000 postpartum hospitalizations. Compared with non-disabled White birthing persons, Black and Hispanic birthing persons with physical disabilities had the highest adjusted risks across all periods: prenatal (adjusted relative risk [aRR] 9.93, 95% confidence interval [CI] 7.32-13.47; aRR 5.67, 95% CI 4.18-7.69; respectively), delivery (aRR 4.65, 95% CI 3.73-5.81; aRR 3.14, 95% CI 2.51-3.93), and postpartum (aRR 4.86, 95% CI 3.44-6.85; aRR 3.50, 95% CI 2.56-4.76). Values of relative excess risk due to interaction indicated significant super-additive interaction, suggesting compounded effects of race/ethnicity and disability.

This population-based study provides evidence that multiply marginalized birthing persons experience compounded health disparities that persist even after adjusting for sociodemographic and clinical factors. Efforts are needed to ensure that persons with multiple marginalized identities have access to comprehensive, accessible, disability-competent, and culturally sensitive maternal and perinatal health care services.