Do low-income women attain their pre-pregnant weight by the 6th week of postpartum?

OBJECTIVES To assess the proportion of women attaining pre-pregnant weight, and to ascertain the predictors of amount of retained weight at 6 weeks postpartum, in a tri-ethnic sample of low-income women. DESIGN Short-term longitudinal design from post-delivery to 6 weeks postpartum. PARTICIPANTS 419 African-American, Hispanic, and White women receiving perinatal care funded by Medicaid. MAIN OUTCOME VARIABLES Proportion of women attaining pre-pregnant weight at 6 weeks postpartum; the amount of weight retained at 6 weeks postpartum. RESULTS Fifteen percent of women attained their pre-pregnant weight at 6 weeks postpartum. In multiple regression analysis, maternal weight gain during pregnancy was the predominant predictor (B=.88, SE=.02, P=.000). Hispanic ethnicity (B=.69, SE=.33, P=.039) and the interaction between maternal weight gain and gestational length (B=-.04, SE=.02, P=.032) made small, independent contributions to amount of retained weight at 6 weeks postpartum. The interaction of ethnicity and maternal age predicted 1.3% of the variance in retained weight, but this was not significant. Health practices were not associated significantly with the amount of weight retained at 6 weeks postpartum. CONCLUSIONS The majority of women did not return to their pre-pregnant weight by 6 weeks postpartum. The amount of retained weight after delivery is largely influenced by prenatal maternal weight gain.