Maternal outcomes associated with weight change between pregnancies.

OBJECTIVE Weight change between pregnancies was examined to determine if there were an association between weight gain (or loss) and delivery by cesarean section, gestational diabetes or pregnancy-induced hypertension. METHODS A cohort study was conducted which included Nova Scotia residents with two or more singleton deliveries between 1988 and 1996. Weight change between pregnancies was calculated as the difference in weight from a woman's initial pre-pregnancy weight and the pre-pregnancy weight recorded from her final recorded pregnancy. RESULTS Weight change between pregnancies was examined in 19,932 women. Women in the highest weight gain category were at an increased risk for developing gestational diabetes (RR = 1.59, 95% CI 1.22-2.08), independent of their weight prior to the final pregnancy, and other confounders. Weight gain (or loss) between pregnancies was not associated with the other outcomes. INTERPRETATION Weight gain between pregnancy is an independent risk factor for gestational diabetes.