Racial/ethnic differences in impact of gestational weight gain on interconception weight change.

Describe the association between gestational weight gain (GWG) and interconception weight change within race/ethnic groups, and differences across them. Data are from linked New York City birth certificates 1994-2004. The sample comprised nulliparous women ages ≥18 with two consecutive singleton births (N = 115,651). The dependent variable was interconception weight change. Adjusted analyses were from ordinary least squares regression model fully interacted by race/ethnic group, controlling for covariates. Within race/ethnic groups, adjusted interconception weight change was calculated for each GWG level compared with GWG 20-24 pounds; across groups, weight change was calculated for each group compared with white non-Hispanics. GWG ≥40 pounds was 18 % for Asian Pacific Islanders, and 27-29 % for other race/ethnic groups. Interconception weight change >15 pounds was highest for black non-Hispanics (34 %) and lowest for Asian Pacific Islanders (17 %). In the multivariable analysis, mean interconception weight change increased with increasing GWG in all race/ethnic groups, an average of 1.5-1.6 pounds for each 5-pound GWG interval. Compared with white non-Hispanics, adjusted mean interconception weight change was higher at every GWG level for black non-Hispanics (3.5-5.1 pounds), and at every level except <15 pounds for Hispanics (1.6-3.0 pounds). GWG ≥40 pounds was prevalent in all groups. GWG contributes to long-term interconception weight change, and non-Hispanic blacks and Hispanics are at risk of greater weight change. Interventions at many levels, during and after pregnancy, are needed to support women to achieve healthy GWG and postpartum weight loss.