Maternal Morbidity and Mortality by Race and Insurance Status

Key Takeaways

• In a U.S. obstetric-delivery sample, 43.8% of deliveries were covered by Medicaid. Medicaid coverage was 66.7% among Black patients, 66.6% among Hispanic patients, 67.6% among Native American patients, 32.3% among White patients, and 27.9% among Asian patients.
• Every race-insurance intersectional group was reported to have higher adjusted odds of severe maternal morbidity than White patients with private insurance, and those differences were statistically significant.
• Within each racial category, Medicaid-covered patients were also reported to have higher severe maternal morbidity odds than privately insured patients, and the maternal mortality pattern was described as primarily tied to Medicaid rather than race.

In a national serial cross-sectional study of severe maternal morbidity and mortality by race and insurance status, investigators analyzed U.S. obstetric deliveries in the National Inpatient Sample from 2015 to 2022, representing 23.5 million weighted deliveries. Severe maternal morbidity (SMM) complications were defined with ICD-10 codes.

Ten interaction terms compared Medicaid with private insurance across White, Black, Hispanic, Asian, and Native American groups. Demographics were compared with bivariate testing using p<0.05 and standardized differences >0.2. Multivariable logistic regression estimated odds ratios and 95% confidence intervals after adjustment for preexisting and gestational comorbidities, year, cesarean section, and hospital region.

Insurance distribution differed markedly across racial groups, with Medicaid covering 66.7% of Black patients, 66.6% of Hispanic patients, and 67.6% of Native American patients. That distribution concentrated public coverage in groups already central to U.S. obstetric inequity.

Among White and Asian patients, Medicaid accounted for 32.3% and 27.9% of deliveries, respectively. For severe maternal morbidity and in-hospital maternal mortality, adjusted comparisons showed higher SMM odds in every race-insurance intersectional group than in White patients with private insurance (all p<0.001). Within each racial category, Medicaid-covered patients also had higher SMM odds than privately insured patients, and increased in-hospital maternal mortality odds were observed primarily with Medicaid rather than by race.

Because this was an observational inpatient analysis, the findings support adjusted associations rather than causation between insurance status, race, and delivery outcomes. The authors interpreted the pattern as suggesting that racial disparities in SMM are amplified among patients with public insurance and framed equitable coverage reform as relevant to obstetrical inequities.

Clinician Questions

How was severe maternal morbidity defined in the race and insurance analysis of U.S. births?

Investigators defined severe maternal morbidity complications using ICD-10 codes in U.S. obstetric deliveries captured in the National Inpatient Sample.

What was the reference group for severe maternal morbidity comparisons across race and insurance status?

Adjusted severe maternal morbidity comparisons used White patients with private insurance as the reference group, and ten interaction terms compared Medicaid versus private insurance across White, Black, Hispanic, Asian, and Native American groups.

Which factors were included in the adjusted models for severe maternal morbidity and in-hospital maternal mortality?

Multivariable logistic regression estimated odds ratios and 95% confidence intervals after adjustment for preexisting and gestational comorbidities, year, cesarean section, and hospital region.