Maternal Nativity, Race, and Ethnicity and Infant Mortality in the US

Importance: Racial disparities in infant mortality in the US are well-established, but the associations among maternal nativity status, race, ethnicity, and infant mortality remain understudied. Objective: To examine the associations among maternal nativity status and infant mortality by maternal race and ethnicity in the US, and to assess whether these associations differ by gestational age. Design, Setting, and Participants: This retrospective, population-based cohort study used linked birth and infant death records for all recorded US live births from 2016 to 2022. Births to foreign residents and those with missing data on maternal nativity, race, ethnicity, or gestational age were excluded. Exposure: Maternal nativity status (US born vs non-US born). Main Outcomes and Measures: The primary outcome was infant mortality, defined as death within 364 days of life. Logistic regression was used to quantify the association between maternal nativity status and infant mortality, adjusting for maternal and infant characteristics. Leading causes of death among preterm (