Erosion of Advantage: Decomposing Differences in Infant Mortality Rates Among Older Non-Hispanic White and Mexican-Origin Mothers

We build on findings from recent research showing an erosion of infant survival advantage in the Mexican-origin population relative to non-Hispanic whites at older maternal ages, with patterns that differ by nativity. This runs counter to the well-documented Hispanic infant mortality paradox and suggests that weathering and/or other negative health selection mechanisms may contribute to increasing disadvantage at older maternal ages. Using the National Center for Health Statistics (NCHS) cohort-linked birth and infant death files, we decompose the difference in Mexican-origin non-Hispanic white infant mortality at older maternal ages to better understand the contribution of selected medical and social risk factors to components of the difference. We find differences in the distribution and effects of risk factors across the three populations of interest. The infant mortality rate (IMR) gap between Mexican-origin women and non-Hispanic whites can be attributed to numerous offsetting factors, with inadequate prenatal care standing out as a major contributor to the IMR difference. Equalizing access to and utilization of prenatal care may provide one possible route to closing the IMR gap at older maternal ages.