Immigration and Low Birthweight in the U.S.: The Role of Time and Timing

Lisa M. Bates, Columbia University
Julien O. Teitler, Columbia University

In the growing literature on the “epidemiologic paradox” among immigrants, particularly of Hispanic origin, and on the effects of acculturation or assimilation processes on health, there is surprisingly little attention to the role of immigrants’ age at arrival as a potential determinant of these adaptive processes and subsequent health outcomes. There is also a lack of explicit recognition that observed health effects of “duration in the US” in cross-sectional studies may actually be reflecting the effects of age at arrival. We pool two birth cohort studies and link birth certificate and survey data to create a uniquely nationally representative sample of over 13,000 births and examine the associations between low birthweight and mother’s nativity, duration in the US, and age at immigration. Our findings support our hypothesis that, due to critical developmental periods in adolescence, immigration before or during this life stage may be associated with worse health outcomes.