Severe Maternal Morbidity and Mortality Risk at the Intersection of Rurality, Race and Ethnicity, and Medicaid

  • Julia D. Interrante
    Correspondence to: Julia D. Interrante, MPH, University of Minnesota School of Public Health, Division of Health Policy and Management, 420 Delaware St. SE MMC 729, Minneapolis, MN 55455. Phone: (612) 624-6151; fax: (612) 624-2196.
    University of Minnesota Rural Health Research Center, Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, Minnesota
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  • Mariana S. Tuttle
    University of Minnesota Rural Health Research Center, Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, Minnesota
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  • Lindsay K. Admon
    Department of Obstetrics and Gynecology and the Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, Michigan
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  • Katy B. Kozhimannil
    University of Minnesota Rural Health Research Center, Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, Minnesota
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      We examined differences in rates of severe maternal morbidity and mortality (SMMM) among Medicaid-funded compared with privately insured hospital births through specific additive and intersectional risk by rural or urban geography, race and ethnicity, and clinical factors.


      We used maternal discharge records from childbirth hospitalizations in the Health care Cost and Utilization Project's National Inpatient Sample from 2007 to 2015. We calculated predicted probabilities using weighted multivariable logistic regressions to estimate adjusted rates of SMMM, examining differences in rates by payer, rurality, race and ethnicity, and clinical factors. To assess the presence and extent of additive risk by payer, with other risk factors, on rates of SMMM, we estimated the proportion of the combined effect that was due to the interaction.


      In this analysis of 6,357,796 hospitalizations for childbirth, 2,932,234 were Medicaid funded and 3,425,562 were privately insured. Controlling for sociodemographic and clinical factors, the highest rate of SMMM (224.9 per 10,000 births) occurred among rural Indigenous Medicaid-funded births. Medicaid-funded births among Black rural and urban residents, and among Hispanic urban residents, also experienced elevated rates and significant additive interaction. Thirty-two percent (Bonferroni-adjusted 95% confidence interval, 19%–45%) of SMMM cases among patients with chronic heart disease were due to payer interaction, and 19% (Bonferroni-adjusted 95% confidence interval, 17%–22%) among those with cesarean birth were due to the interaction.


      Heightened rates of SMMM among Medicaid-funded births indicate an opportunity for tailored state and federal policy responses to address the particular maternal health challenges faced by Medicaid beneficiaries, including Black, Indigenous, and rural residents.
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      Julia D. Interrante, MPH, is a doctoral candidate in the Division of Health Policy and Management at the University of Minnesota. Her work examines the impact of health policy on reproductive and maternal health.


      Mariana S. Tuttle, MPH, is a research and communications fellow at the University of Minnesota Rural Health Research Center. Her research focuses on rural health across the lifespan, from maternal and child health to aging and older adults.


      Lindsay K. Admon, MD, MSc, is an Assistant Professor and obstetrician-gynecologist at the University of Michigan. Her research addresses disparities in maternal health and the evaluation of strategies to improve maternal and child health outcomes.


      Katy B. Kozhimannil, PhD, MPA, is Distinguished McKnight Professor, University of Minnesota School of Public Health, and Director of the University's Rural Health Research Center. Her research contributes evidence for clinical and policy strategies advancing racial, gender, and geographic equity.