Background <p>Infant mortality remains a critical public health concern in the United States, with disparities by race and maternal marital status. In response, Alabama implemented a pilot initiative in 2019 to reduce the state’s high infant mortality rate (IMR). This study evaluates the program’s effectiveness in mitigating IMR disparities across race and marital status.</p> Methods <p>We utilized linked birth and infant death certificate data from 2014 to 2023 to assess program impact. A difference-in-differences (DiD) design and synthetic control approach were applied to a sample of over 400,000 births, comparing two pilot counties (Montgomery and Macon) to the rest of Alabama. Outcomes were stratified by maternal race (Black, White) and marital status (married, single).</p> Results <p>Causal evidence from both the DiD and synthetic control analyses indicates that the program reduced IMR among White married mothers (–0.0016; –39.8%, <i>p</i> = 0.001). In contrast, Black married mothers experienced an increase in IMR (+ 0.0043; + 54.7%, <i>p</i> = 0.014) that was not statistically robust in DiD but confirmed by the synthetic control method, suggesting a likely causal adverse effect. No significant changes in IMR were detected for Black single (<i>p</i> = 0.862) or White single mothers (<i>p</i> = 0.777).</p> Conclusions <p>The pilot program produced improvements only for White married mothers. Disaggregated analysis revealed the necessity of jointly considering race and marital status to understand and address infant health inequities.</p> Public health implications <p>Efforts to reduce IMR disparities must integrate both racial and social determinants—such as marital status. Resource allocation and program design should combine clinical services with broader social supports and prioritize the most vulnerable populations to effectively close persistent gaps in IMR.</p>