Abortion Restrictiveness and Infant Mortality: An Ecologic Study, 2014-2018

Abstract

The United States (U.S.) has the highest infant mortality rate among peer countries. Restrictive abortion laws may contribute to poor infant health outcomes. This ecological study investigated the association between county-level infant mortality and state-level abortion access legislation in the U.S. from 2014 - 2018. A multivariable regression analysis with the outcome of county-level infant mortality rates (IMR), controlling for the primary exposure of state-level abortion laws, and county-level factors, county-level distance to an abortion facility, and state Medicaid expansion status was performed. Incidence rate ratios (IRR) and 95% confidence intervals (CI) were reported. Analyses were conducted from 2022-2023. There were 113,397 infant deaths among 19,559,660 live births (IMR 5.79 deaths/1,000 live births, 95%CI 5.75, 5.82). Black IMR (10.69/1,000) was more than twice that of White infants (4.87/1,000). In the multivariable model, increased IMR was seen in states with ≥ 8 restrictive laws, with the most restrictive (11-12 laws) having a 16% increased IMR (aIRR 1.162 (95%CI 1.103, 1.224). Increased IMRs were associated with increased county-level Black race individuals (aIRR 1.031, 95%CI 1.026, 1.037), high school education (aIRR 1.018, 95%CI 1.008, 1.029), maternal smoking (aIRR 1.025, 95%CI 1.018, 1.033), and inadequate prenatal care (aIRR 1.045, 95%CI 1.036, 1.055). State-level abortion law restrictiveness is associated with higher county-level infant mortality rates. The Supreme Court decision on Dobbs v. Jackson and changes in state laws limiting abortion may affect future infant mortality.