Prenatal Drug Use and the Production of Infant Health

We estimate the effect of illicit drug use during pregnancy on low birth weight. We use data from a national longitudinal study of urban parents that includes post-partum interviews with mothers, hospital medical record data on the mother and newborn, extensive demographic information on both parents, and information about the city where the mother resides. We address the potential endogeneity of prenatal drug use and present estimates using alternative measures of prenatal illicit drug use. Depending on how drug use is measured, we find deleterious effects of illicit drug use on low birth weight that range from 3 to 5 percentage points.