Prediction of Gestational Diabetes Mellitus By Different Obesity Indices

Abstract Background: The incidence rate of obesity and gestational diabetes mellitus (GDM) is increasing in parallel. This study aimed to evaluate the relationship between different obesity indices including pre-pregnancy body mass index(preBMI), the first trimester abdominal circumference (AC), the first trimester abdominal circumference/height ratio (ACHtR) and GDM, and the efficacy of these three indices in predicting GDM.Methods: A total of 15472 pregnant women gave birth to a single child at the Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China. Weight before pregnancy, height and AC were asked and measured at the first prenatal examination at 11-13+6 gestational weeks. GDM was diagnosed through a 75g oral glucose tolerance test at 24–28 gestational weeks. Using receiver operator characteristic (ROC) curve analysis, we evaluated the association between the obesity indices and GDM. Results: Multivariate logistic regression analysis showed that AC, the ACHtR，and preBMI（P＜0.001） were all independent risk factors for the development of GDM. In the normal BMI population, the higher the AC or the ACHtR, the more likely the pregnant women were to suffer from GDM. The area under the ROC curve (AUC) was 0.63 (95% CI 0.62-0.64) for AC ,0.64 (95% CI 0.63-0.65) for the ACHtR and 0.63 (95% CI 0.62-0.64) for preBMI. An AC ≥ 80.25cm(sensitivity 61.6%, specificity 57.9%), an ACHtR of ≥0. 49 (sensitivity 67.3%, specificity 54%), and a preBMI ≥22.74 (sensitivity 48.4%, specificity 71.8%) were determined to be the best cut-off levels for identifying subjects with GDM. Conclusions: AC, the ACHtR and preBMI had value in predicting GDM. The increase in AC and the ACHtR in the first trimester of pregnancy and preBMI could be independent risk factors for GDM. Even in the normal BMI population, the higher the AC is, the more likely the pregnant women are to suffer from GDM.