WIC Participation and the Education-Related Gap in Adverse Neonatal Outcomes: A Population-Based Cohort Study

BACKGROUND: Lower maternal educational attainment is associated with adverse neonatal outcomes, including lower birthweight, low birthweight, and neonatal intensive care unit (NICU) admission. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) is intended to improve nutritional and pregnancy outcomes among socioeconomically vulnerable mothers, but whether WIC participation attenuates education-related neonatal disparities remains uncertain. OBJECTIVE: To examine whether WIC participation is associated with narrowing of the neonatal outcome gap between mothers with lower and higher educational attainment. METHODS: We conducted a population-based retrospective cohort study using the 2024 United States Natality Public Use File. The analysis was restricted to singleton live births with maternal education and WIC status. Lower education was defined as high school/GED or less, and higher education as bachelor's degree or higher. Outcomes were birthweight, low birthweight (<2500 g), and NICU admission. Crude outcomes were compared across four education-WIC groups. Multivariable generalized linear models adjusted for maternal age, race and Hispanic origin, marital status, prenatal care timing, prepregnancy body mass index, smoking, maternal medical risk factors, live-birth order, and infant sex. The primary parameter was the education-by-WIC interaction. RESULTS: The analytic cohort included 2,570,707 births. In crude analyses, the low-vs-high education gap in low birthweight was 3.56 percentage points among non-WIC births and 1.78 percentage points among WIC births; corresponding NICU admission gaps were 2.03 and 0.77 percentage points. In adjusted models, lower education was associated with lower birthweight and higher risks of low birthweight and NICU admission. WIC participation attenuated these disparities: the education-by-WIC interaction was +21.3 g for birthweight, -0.9 percentage points for low birthweight, and -0.7 percentage points for NICU admission (all p<.001). CONCLUSION: WIC participation was associated with smaller education-related disparities in birthweight, low birthweight, and NICU admission. These findings support WIC as a populationlevel mechanism for reducing neonatal outcome disparities.