The Impact of Maternal Age, Pre-Pregnancy Body Mass Index, Weight Gain and Parity on Glucose Challenge Test (GCT)

Background: Gestational diabetes mellitus (GDM) complicates 3-7% of all pregnancies and feto-maternal outcomes are strongly related to early diagnosis of GDM. The aim of this study was to determine the impact of risk factors in the prediction of an abnormal glucose challenge test (GCT). Materials and Methods: This was a prospective study conducted during 2009-2010 in two prenatal clinics in Rey, Iran. A total of 711 pregnant women who were in their first trimester of pregnancy and met the inclusion criteria were selected. The women were observed once every other week until 24-28 weeks of gestation. All patients at 24-28 weeks of gestation were screened with 50 g oral glucose GCT. The effects of pre-pregnancy body mass index (BMI), maternal age, and weight gain until the time of GCT, and parity on abnormal GCT were evaluated. All confident intervals were calculated at the 95% level. Data was analyzed using student's t test and the logistic regression test. Results: Maternal age (p<0.001), pre-pregnancy BMI (p<0.00), parity (p=0.05) and weight gain during pregnancy (p=0.05), were significantly higher in women with abnormal GCT compared to women who had normal GCT. Logistic regression analyses confirmed that pre-pregnancy BM I (OR=1.09), maternal age (OR=1.14), and weight gain during pregnancy (OR=1.13) were associated with abnormal GCT. Conclusion: Weight gain had a profound impact on the prevalence of abnormal GCT in our population. Therefore, we propose that pregnant women should only gain the recommended amount of weight during pregnancy.