Birthweight of children of immigrants by maternal duration of residence in the United States

► We find that associations between duration of residence in the U.S. and birthweight of immigrant women's children are not monotonically negative as acculturation theory suggests. ► There appears to be an initial improvement in birthweight during the first few years that immigrant women spend in the U.S., followed by a subsequent decline. ► The findings are consistent across 3 national studies, for all immigrants and for Hispanic immigrants, and for birthweight and low birthweight. ► There does not appear to be a convergence over time in the prenatal health behaviors (smoking, drinking, drug use) of immigrant and native-born mothers.