INTRODUCTION: This study assesses the impact of a culturally modified, motivationally targeted, individually tailored intervention on postpartum weight retention among Hispanic women with abnormal glucose tolerance during pregnancy. METHODS: Estudio Parto (Project Aiming to Reduce Type twO diabetes) was an RCT conducted in Western Massachusetts (collected 20132017, analyzed 2018-2020). Hispanic women with blood glucose > /=140 mg/dL (7.77 mmol/L) on routine nonfasting oral glucose challenge test were randomized to a Lifestyle Intervention (n=100) focusing on healthy exercise and diet or to a comparison Health and Wellness Intervention (n=104) with no mention of exercise or diet behavior changes. The primary outcome was change in weight, calculated as the difference between prepregnancy weight and 6-week, 6-month, and 12-month postpartum weight. The secondary outcome was achievement of weight reduction to prepregnancy weight if prepregnancy BMI was normal, or a 5% reduction if prepregnancy BMI was overweight/obese. RESULTS: In intent-to-treat analyses, there were no significant differences in weight change pattern between the intervention arms across all follow-up timepoints (beta=0.03, 95% CI= -3.38, 3.45). However, at 12 months postpartum, women in the Lifestyle Intervention arm had a statistically significant 2.5-fold higher odds of meeting the secondary weight reduction outcome (OR=2.52, 95% CI=1.09, 5.82) than women in the Health and Wellness arm. Regardless of intervention arm, women who reported higher levels of postpartum sports/exercise had a greater decrease in weight (beta= -2.39, 95% CI= -4.66, -0.13, p=0.04) than women reporting lower levels. CONCLUSIONS: In this randomized trial among Hispanic women, no significant overall differences in weight change pattern between intervention arms were observed. Higher levels of self-reported physical activity were associated with greater weight loss in both arms.