Table 4 shows the incidence of GDM later in their pregnancy. The study group had a significantly greater incidence of GDM than the control group (21.9%and 1.8%, respectively, RR 12.5, 95%CI 3.0-51.5). All GDM cases were in class A1. Multiple logistic regression analysis was used to determine the association between abnormal 1 value of OGTT and the development of GDM, adjusted for age. The result shows that adjusted OR was 16.3 (95%CI 3.7-71.9). Women in the study group were 16.3 times more likely to develop GDM later in their pregnancy, compared with those in the control group.