Previous research has generally found exclusive breastfeeding to protect against asthma in young children. However, maternal nativity in a Latina population has not been assessed as a potential confounder or effect modifier. Using cross-sectional data restricted to Latina mothers (n = 704) from a birth cohort in Los Angeles interviewed in 2003 and 2006, we estimated risk ratios (RR) for exclusive breastfeeding and asthmatic symptoms in the offspring. 56 children (8%) had asthmatic symptoms at age 3.5 years. We found a 49% reduction in risk of asthmatic symptoms with >3 months of exclusive breastfeeding (aRR 0.51, 95% CI 0.28, 0.90). Foreign-born Latinas were more likely to initiate and continue breastfeeding for at least 3 months compared with US-born Latinas. Three or more months of exclusive breastfeeding reduced the risk of asthmatic symptoms in the offspring of Latinas, and maternal nativity did not confound or modify this association.
Keywords: Asthma; Breastfeeding; Epidemiology; Immigrant health; Maternal nativity.