The obese woman with gestational diabetes: effects of body mass index and weight gain in pregnancy on obstetric and glycaemic outcomes.

BACKGROUND

Obese women with gestational diabetes mellitus (GDM) represent a high-risk group in pregnancy, although the effects of increasing degrees of obesity and weight gain in pregnancy in this group is poorly defined.

METHODS

We performed a retrospective analysis of 375 singleton pregnancies complicated by maternal obesity and GDM. Women with a body mass index (BMI) of 30-35 kg/m(2) were compared with those with a BMI of ≥ 35 kg/m(2). Additionally, women were categorized according to weight gain in pregnancy: Group A (<0.18 kg/week), Group B (0.18-0.27 kg/week), Group C (>0.27 kg/week).

RESULTS

Obstetric outcomes did not differ between the groups; however, postpartum dysglycaemia was more likely in women with a BMI ≥ 35 kg/m(2) (odds ratio [OR] 3.2, 95% confidence interval [CI]: 1.2-8.9). Group B and Group C had higher odds of LGA (OR 3.8, 95% CI: 1.3-11.3; OR 5.0, 95% CI: 2.0-12.1, respectively) compared with Group A. Group C also had a lower risk of SGA (OR 0.4, 95% CI: 0.2-1.0) and a higher risk of postpartum dysglycaemia (OR 6.8, 95% CI: 1.7-26.9) compared with Group A.

CONCLUSION

Greater degrees of obesity are associated with higher risk of abnormal metabolic outcomes after pregnancy. Excessive weight gain in pregnancy in obese women increases adverse obstetric and glycaemic outcomes. Our findings suggest that targets for weight gain in pregnancy for obese women should be reduced from current recommendations.