The secondary aim is to estimate the effect of IPT integrated into usual prenatal care, in comparison to usual care only, on key healthcare outcomes grounded in the theoretical framework, including perinatal social functioning, perceived stress, depression symptoms, eating behavior, physical activity, sleep, GWG, delivery outcomes, and at 3-months postpartum, maternal weight retention, maternal/infant adiposity, and maternal insulin sensitivity. This evidence concerns the gene INS and depressive disorder.