Metropolitan residential segregation and very preterm birth among African American and Mexican-origin women.

Residential segregation is associated with poor health-including poor birth outcomes-among African Americans in US cities and metropolitan areas. However, the few existing studies of this relationship among Mexican-origin women have produced mixed results. In this study, the relationship between segregation and very preterm birth was examined with National Center for Health Statistics (NCHS) data on singleton births to African American women (n = 400,718) in 238 metropolitan areas and to Mexican-origin women (n = 552,382) in 170 metropolitan areas. The study evaluated 1) whether residential segregation is positively associated with very preterm birth among both African American and Mexican-origin women and 2) if so, whether exposure to neighborhood poverty accounts for these associations. Results from multi-level analysis indicate that residential segregation is positively associated with very preterm birth among both groups of women. However, this association is robust across different measures of segregation only for African Americans. Conversely, differences across metropolitan areas in average levels of exposure to neighborhood poverty account for the positive association between segregation and very preterm birth among Mexican-origin women, but not among African American women.