Poster session II Clinical obstetrics, diabetes, labor, medical-surgical-disease, physiology/endocrinology, prematurity: Abstracts 237 - 386| Volume 208, ISSUE 1, SUPPLEMENT , S112, January 01, 2013

244: Risk of gestational diabetes mellitus analysed by the rate of weight gain before screening


      While maternal obesity increases the risk of Gestational Diabetes Mellitus (GDM), there is little evidence that decreased Gestational Weight Gain (GWG) in obese women (according to the Institute of Medicine revised recommendations) improves glucose tolerance. Also, previous studies use Total GWG rather than the rate of GWG before the Glucose Tolerance Test (GTT) was performed. This prospective observational study compared the incidence of GDM in women with a GWG/week > the mean with that in women with a GWG/week < the mean before their GTT for each Body Mass Index (BMI) category.

      Study Design

      All women had a dating ultrasound and weight and height measured in the first trimester. They were enrolled at their convenience when undergoing selective screening for GDM at 28 weeks gestation with a 100g oral GTT. Clinical and demographic details were recorded.


      Of the 499 women, the mean age was 31.0 years and 39.5% (n=197) were primigravidas. The number of obese women was 35.7% (n=178) which was high because obesity is an indication for selective screening. The incidence of GDM was 16.2% in obese women compared with 10.4% in women with a normal BMI (p<0.05). The overall mean GWG/week was 0.45kg (p<0.05); with mean GWG/week being 0.5 kg in the normal and overweight BMI groups but only 0.4kg in the obese group. The risk of GDM analysed by the rate of GWG/week before the GTT is shown in the Table.
      Tabled 1Risk of gestational diabetes mellitus analysed by mean GWG/week before screening
      Table thumbnail grr7


      Although obese women put on less GWG/week before the GTT than non-obese women, they were more likely to develop GDM. In each BMI category, the risk of GDM was not significantly increased in women who put on more than the mean GWG/week before their GTT was performed, compared with women who put on less. Thus, to prevent GDM developing efforts should focus on modifying pre-pregnancy weight excess, rather than excessive GWG.