Timing of gestational weight gain in relation to weight retention and body composition at 6- and 12-months postpartum

Gestational weight gain contributes to postpartum weight retention and may also influence body composition in the first year postpartum, a critical time for weight stabilization post pregnancy. Furthermore, timing of gestational weight gain may influence postpartum weight and body composition, which is a better predictor of long-term health. To examine gestational weight gain (GWG) (total and by trimester) in relation to weight and adiposity-related outcomes in the postpartum. In a U.S. pregnancy cohort ( n = 174), we examined weight, body mass index (BMI), and body composition (total and truncal adiposity percentage, visceral adiposity rating) using Bioelectrical Impedance Analysis at 6- and 12- months postpartum in relation to total and trimester specific GWG (in kg), adjusting for covariates. Forty-four percent of participants gained within Institute of Medicine guidelines; 39% gained above the guidelines; and 17% gained below the guidelines. Total GWG was positively associated with BMI and adiposity measures at 6- and 12-months postpartum. For example, GWG was associated with higher BMI at 6- (β = 0.20; 95%CI: 0.15, 0.26) and 12-months (β = 0.18, 95%CI: 0.11, 0.26) postpartum. Postpartum visceral adiposity was associated with weight gain in every trimester, whereas total adiposity (β = 0.29, 95%CI: 0.04, 0.53) and truncal adiposity (β = 0.32; 95%CI: 0.00, 0.64) percentages were associated with 3rd trimester weight gain specifically. For women with obesity, weight gain in every trimester was associated with BMI (β = 0. 25; 95%CI: 0.16, 0.34) and visceral adiposity ratings (β = 0.15; 95%CI: 0.09, 0.21) at 6-months postpartum and visceral adiposity ratings (β = 0.09; 95%CI: 0.03, 0.16) at 12-months postpartum. GWG may influence BMI and body composition in the first year postpartum, particularly for women with obesity. Patterns of GWG may have implications for postpartum body composition and cardiometabolic health.