Excessive gestational weight gain is associated with long-term body fat and weight retention at 7 y postpartum in African American and Dominican mothers with underweight, normal, and overweight prepregnancy BMI.

Background: Excessive gestational weight gain (GWG) is associated with postpartum weight retention (PPWR) and abdominal adiposity, but long-term effects are understudied in low-income and minority populations at high risk of obesity and associated sequelae.

Objective: We examined associations between GWG and long-term PPWR and adiposity in a prospective cohort of African American and Dominican mothers in the Bronx and Northern Manhattan.

Methods: Women (n = 302) were enrolled during pregnancy and were followed for 7 y postpartum. Linear regression was used to relate excessive GWG [greater than 2009 Institute of Medicine (IOM) guidelines] to outcomes [percentage body fat and long-term PPWR (change in weight from prepregnancy to 7 y postpartum)], adjusting for covariates and included an interaction term between prepregnancy body mass index (BMI; in kg/m(2)) and GWG.

Results: Mean ± SD prepregnancy BMI and total GWG were 25.6 ± 5.8 (42% of women had BMI ≥25) and 16.6 ± 7.8 kg (64% of women had total GWG greater than IOM guidelines), respectively. Associations between GWG and long-term PPWR and the percentage body fat varied by prepregnancy BMI (P-interaction ≤ 0.06); excessive GWG was associated with a higher percentage body fat and greater long-term PPWR in mothers with lower prepregnancy BMI. To illustrate the interaction, a predicted covariate-adjusted model, which was used to derive estimates for the percentage body fat and PPWR associated with excessive GWG, was estimated for 2 prepregnancy BMI examples. For a woman with prepregnancy BMI of 22, excessive GWG was associated with 3.0% higher body fat (P < 0.001) and a 5.6-kg higher PPWR (P < 0.001); however, for a woman with a prepregnancy BMI of 30, excessive GWG was associated with 0.58% higher body fat (P = 0.55) and 2.06 kg PPWR (P = 0.24).

Conclusions: Long-term adiposity and PPWR in low-income African American and Dominican mothers were predicted by interacting effects of prepregnancy BMI and excessive GWG. The provision of support for mothers to begin pregnancy at a healthy weight and to gain weight appropriately during pregnancy may have important lasting implications for weight-related health in this population. This study was registered at clinicaltrials.gov as NCT00043498.