The intervention is a multi-component program designed to prevent excessive gestational weight gain in overweight and obese women and to promote weight loss in their non-pregnant overweight and obese partners through modifications of diet, exercise, and behavioral strategies during pregnancy.

Rate of gestational weight gain will be computed as difference between weights measured at study entry and gestational week 35; this difference will be divided by the number of weeks of observation during pregnancy (i.e., weeks between study entry and final pregnancy assessment). If gestational week 35 is unavailable, most proximal clinic visit weight will be used.

Weight lost by the non-pregnant partner during the study will be assessed by subtracting their weight at the 35 week gestation visit from their study entry weight.