A large body of evidence indicates that conditions in-utero and health at birth matter for individuals' long-run outcomes, suggesting potential value in programs aimed at pregnant women and young children. This paper uses a novel identification strategy and data from birth and administrative records over 2005-2009 to provide causal estimates of the effects of geographic access to the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). My empirical approach uses within-ZIP-code variation in WIC clinic presence together with maternal fixed effects, and accounts for the potential endogeneity of mobility, gestational-age bias, and measurement error in gestation. I find that access to WIC increases food benefit take-up, pregnancy weight gain, birth weight, and the probability of breastfeeding initiation at the time of hospital discharge. The estimated effects are strongest for mothers with a high school education or less, who are most likely eligible for WIC services.
Keywords: WIC; health at birth; low-income women and children; pregnancy; public programs.