To determine the association between Medicaid expansion and infant mortality rate (IMR) in the United States.
State‐level aggregate data on US IMR, race, and sex were abstracted from the US Center for Disease Control and Prevention's Wide‐ranging Online Data for Epidemiologic Research.
The association between Medicaid expansion and IMR adjusted for race and sex was assessed with multiple linear regression models using difference‐in‐differences estimation and Huber‐White robust standard errors.
Difference‐in‐differences regression found no association between Medicaid expansion status and change in national IMR from 2010 to 2017 (Coef. = 0.04; 95% CI: −0.39, 0.46). However, among Hispanics, the program was found to be associated with reduction in IMR (Diff‐in‐Diff Coef. = −0.53; 95% CI: −1.02, −0.03).
Overall, the Affordable Care Act–induced Medicaid expansion was not associated with IMR reduction in expansion states relative to nonexpansion states. However, the program was associated with a significant IMR decline among Hispanics.