Rethinking the Hispanic Paradox: Favorable Low Birth Weight Outcomes Obscure a Hidden Epidemic of Large-For-Gestational-Age Births

The Hispanic epidemiological paradox suggests that Mexican-born mothers deliver “healthier” babies after migrating to the U.S. based on their lower odds of delivering a low birth weight infant. However, measuring birth outcome using only the standard for low birth weight ignores the possibility that babies weighing more than 2500 grams are large-for-gestational-age (LGA). LGA babies suffer sequelae similar to low birth weight babies over the life course, such as obesity, diabetes, and cardiovascular disease. Analysis of a retrospective cohort of mothers of Mexican origin (N=85,755) delivering singletons in Colorado during 2000 – 2005 and qualitative interviews tested the social gradient of health and explored the healthy migrant and healthy immigrant hypotheses often posited to explain the paradox. Mexican-born mothers are 45% more likely to deliver an LGA baby in Colorado than mothers of Mexican origin born in the U.S. This result is not simply a shift in the population curve of birth weight. Rather this hidden epidemic of LGA babies among Mexican-born mothers is a function of structural barriers including poverty, lack of access to healthy foods, and abrupt changes in energy expenditure and diet, along with linguistic isolation upon immigration. Foreign-born immigrants are often under- or uninsured and do not have adequate access to prenatal care. Public health policy should broaden its approach to measures of weight-related birth outcomes to include LGA and should support greater outreach and prenatal care to foreign-born immigrants.