Comparison of Universal and Risk Factor Based Screening Strategies for Gestational Diabetes Mellitus.

Early diagnosis of gestational diabetes mellitus (GDM) can avoid some diabetes-related complications. To compare the results of oral glucose challenge test (OGCT) in high risk group with low risk group in Iran. In a prospective study, universal screening for GDM was performed on all pregnant women with a 50 g OGCT with 140 mg/dl cut-off point. Data were analyzed between positive and negative groups. A positive 50 g OGCT was obtained in 16.7% of the women. In 4% of women, a diagnosis of GDM was established by the subsequent OGTT 75g. 50.7% of patients with positive OGCT 50 g would not have risk factors. Maternal age>30 years (P<0.0001), recurrent abortion (p=0.04), family history of diabetes (p=0.0004), history of diabetes in previous pregnancies (P<0.0001), glucosuria (P<0.0001), macrosomia (p=0.02) and previous congenital fetal malformation (p=0.001) were significantly different between the positive GCT group and the normal pregnant women. But the mean number of parity, gestational age, hypertention and still birth were not significantly different between the positive GCT group and the other group. The results suggest that the incidence of abnormal OGCT and prevalence of GDM in Iran is comparable to the reported range in other countries and most but not all of the worldwide recognized risk factors were valid for our population. Therefore, universal screening for GDM identify a higher number of GDM than risk factor based screening.