The healthy migrant theory: Variations in pregnancy outcomes among US-born migrants

Various studies have observed that infants born to foreign-born women have better birth outcomes (lower rates of preterm, low birth weight, and infant mortality) than those delivered to US-born women. While much attention has been given to the “healthy migrant effect” as an explanation for these positive outcomes, this theory has not been examined in an internally migrant population. The purpose of this study is to examine the relationship between maternal mobility history and birth outcomes among infants born to US resident mothers of Mexican origin. The study used 1995–1999 National Center for Health Statistics (NCHS) live birth/infant death cohort files of singleton infants delivered in the US to white women of Mexican origin (n=2,446,253).