Perinatal Risk and Outcomes Among Individuals Insured by Medicare

Abstract Pregnant Medicare beneficiaries are typically individuals with chronic conditions causing disability or end-stage organ disease, which may increase obstetric risk. Few studies have examined this population. We compared medical comorbidities and perinatal outcomes between Medicare-insured and non-Medicare-insured obstetric patients. We performed a cross-sectional analysis of the 2019 Healthcare Cost and Utilization Project National Inpatient Sample, including singleton deliveries (Major Diagnostic Category 14). Using discharge weights, strata, and hospital clusters, we compared Medicare with all other payers across maternal demographics, chronic conditions, and perinatal outcomes, including severe maternal morbidity (SMM). Relative risks (RR) were estimated from survey-weighted log-link quasi-Poisson models; a two-sided α < 0.05 indicated significance. Of 3,697,605 deliveries, 28,855 were Medicare-insured. Medicare beneficiaries were more likely to be Black (33.3 vs. 9.5%) and of advanced maternal age (25.4 vs. 23.4%) and had higher rates of chronic kidney disease, prepregnancy hypertension and diabetes, cesarean delivery (37.7 vs. 35.1%), and preterm birth (13.6 vs. 7.5%) than privately insured patients (all p < 0.001). Relative to Medicare, privately insured patients had lower risk of SMM (RR: 0.28; 95% confidence interval: 0.25–0.32). Pregnant Medicare beneficiaries enter pregnancy with a higher chronic disease burden and experience worse maternal and perinatal outcomes, highlighting the need for targeted support of this vulnerable population.