Immigration policy shocks and infant health.

This paper evaluates the effect of positive and negative immigration policy shocks on infant health outcomes in the U.S. I examine changes in mean birth weight and the incidence of low birth weight (LBW) at the metropolitan statistical area (MSA) level around two major institutional shocks: The 1986 Immigration Reform Act (IRCA), which favored immigrants, and the increase in Immigration and Customs Enforcement (ICE) agency arrests at the start of 2017 which might have put immigrants at greater risk of apprehension. It uses a triple difference approach, comparing birth outcomes of foreign-born mothers with U.S.-born mothers (relative to mothers living in MSAs with a higher and lower concentration of IRCA applications and an increase in ICE arrests) before and after the two immigration policies. I find that in MSAs that had higher IRCA applications, mean birth weight increased, and the incidence of LBW decreased by 3-6 percent for babies born to foreign-born mothers. By contrast, in MSAs that had higher ICE arrests starting in 2017, mean birth weight decreased, and the incidence of LBW increased by 3-7 percent for babies born to foreign-born mothers. The effect of the increase in ICE arrests was more pronounced among mothers who were born in Latin and Central American countries. Sub-sample analysis shows that the incidence of LBW increased by as much as 12 percent for babies born to foreign-born mothers of Hispanic origin.