WIC in your neighborhood: New evidence on the impacts of geographic access to clinics

• I study the causal effects of geographic access to WIC.
• WIC is the major U.S. nutrition program for low-income women and children.
• I find that zip-code-level WIC clinic presence increases food benefit take-up.
• WIC clinic access affects pregnancy behaviors, birth weight, and breastfeeding.

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.