A Postpartum Weight Loss-focused Stepped-care Intervention in a Military Population: A Randomized Controlled Trial

Abstract Objective Postpartum weight retention is associated with adverse health among both civilian and military women. Purpose The current study evaluated a stepped-care weight management intervention, Moms Fit 2 Fight, adapted for use in a pregnant and postpartum military population. Methods Active duty women and other TRICARE beneficiaries (N = 430) were randomized to one of three conditions: gestational weight gain only (GWG-only) intervention (n =144), postpartum weight loss only (PPWL-only) intervention (n =142), or a combined GWG + PPWL intervention (n = 144). Those participants who received the PPWL intervention (i.e., the PPWL-only and GWG+PPWL conditions) were combined consistently with the pre-registered protocol and compared to those participants who did not receive the PPWL intervention in the primary analyses. Primary outcome data (i.e., postpartum weight retention) were obtained at 6-months postpartum by unblinded data collectors, and intent-to-treat analyses were conducted. Results Retention at 6-months postpartum was 88.4%. Participants who received the PPWL intervention retained marginally less weight (1.31 kg) compared to participants that received the GWG-only intervention (2.39 kg), with a difference of 1.08 kg (p = .07). None of the measured covariates, including breastfeeding status, were significantly associated with postpartum weight retention. Of the participants who received the PPWL intervention, 48.1% participants returned to their pre-pregnancy weight at 6-months postpartum, with no significant differences compared to those who received the GWG-only intervention. Conclusions A behavioral intervention targeting diet and physical activity during the postpartum period had a trend for reduced postpartum weight retention. Clinical Trial information The trial is registered on clinicaltrials.gov (NCT 03057808). Lay Summary Since postpartum weight retention is associated with negative health outcomes among women in the military and women in the general population, the Moms Fit 2 Fight study evaluated a stepped-care weight management intervention among active duty women and other military health insurance beneficiaries. Participants (N = 430) were recruited in their first trimester of pregnancy and randomized to one of three conditions: pregnancy weight gain-only intervention, postpartum weight loss (PPWL)-only intervention, or a combined pregnancy weight gain and PPWL intervention. Participants who received the PPWL intervention (i.e