Weight gain in women with gestational diabetes.

OBJECTIVE: To evaluate weight gain during pregnancy in women with gestational diabetes, and to determine whether there was a stronger or weaker correlation of maternal weight gain with neonatal birth weight in women with gestational diabetes as compared with a control group.
METHODS: At delivery, 78 women with gestational diabetes and 312 control subjects were evaluated and classified according to pregravid weight for height (underweight, average weight, and overweight). Weight gain during pregnancy and neonatal birth weight in the women with gestational diabetes and in the control group were compared using analysis of covariance, controlling for selected covariables. A weight gain curve for each patient was generated to assess the rate of weight gain during early, middle, and late gestation. Linear regression analysis was used to correlate maternal weight gain and birth weight.
RESULTS: Weight gain was 2.5 kg less in the women with gestational diabetes as compared with the controls (P = .0006). When adjusted for pregravid weight, maternal age, and gestational age at delivery, only underweight women with gestational diabetes persisted in having significantly less weight gain as compared with the control subjects (P = .035). There were no significant differences in infant birth weight between any gestational diabetes and control weight categories. The rate of weight gain was decreased in over-weight women with gestational diabetes versus control subjects in late pregnancy (P = .05). There was a significant correlation between maternal weight gain and birth weight in underweight (r = 0.46, P = .0001) and average-weight (r = 0.17, P = .02) control women but not in overweight controls or in any patients with gestational diabetes.
CONCLUSION: Weight gain in women with gestational diabetes is less than in control patients, primarily because of greater pregravid weight, and does not correlate with neonatal birth weight.