Objective: Our aim was to study whether universal screening of all pregnant women by Oral Glucose Challenge Test (OGCT) would identify a higher number of women with Gestational Diabetes (GDM) than risk factor based screening. Study design: A 50 g OGCT test was performed prospectively in 532 unselected women at 26- 28 weeks of gestation. The 1h venous plasma glucose concentration of >7.3 mmol/l was considered as a positive screening result. Patients with a positive OGCT underwent a 75 g 2- h OGTT, which was used as the actual diagnostic test for GDM. When two or all three of the glucose concentrations in OGTT (measured at fasting state and1and 2h afterthe 75g glucose load) were above the 97.5th percentile the patient was considered as having GDM. In addition, women with risk factors for GDM also underwent a 75 g OGTT regardless of the result of the OGCT. Results: A positive 50 g OGCT was obtained in 123 (23% ) of the women. In 15 (12% ) of these, a diagnosis of GDM was established by the subsequent OGTT. Out of the 409 remaining women with a normal OGCT, 148 (36% ) had risk factors for GDM. An OGTT performed in these patients identified 4 additional women with a GDM. Seventy-nine percent of GDM was thus found with 50 g OGCT without regarding risk factors. Forty-seven percent of the women with GDM would have been missed in screening by risk factors only. Conclusions: In our population 50 g OGCT appears to identify a higher number of GDM than risk factor based screening. Combined with risk factor screening a few more cases of GDM would be found. Objective: Our objective was to study whether universal screening of all pregnant women by Oral Glucose Challenge Test (OGCT) would identify a higher number of women with Gestational Diabetes (GDM) than risk factor based screening. Study design: A 50 g OGCT test was The prospectively in 532 unselected women at 26- 28 weeks of gestation. The 1h venous plasma glucose concentration> 7.3 mmol / l was considered as a positive screening result. Patients with a positive OGCT underwent a 75 g 2- h OGTT, which was used as the actual diagnostic test for GDM. When two or all three of the glucose concentrations in OGTT (measured at fasting state and 1 and 2h afterthe 75g glucose load) were above 97.5th percentile the patient was considered as having having GDM. with risk factors for GDM also underwent a 75 g OGTT regardless of the result of the OGCT. Results: A positive 50 g OGCT was obtained in 123 (23%) of the women. In 15 (12%) of these, a diagnosis of GDM was established by th Out of the 409 remaining women with a normal OGCT, 148 (36%) had risk factors for GDM. An OGTT performed in these patients identified 4 additional women with a GDM. Seventy-nine percent of GDM was thus found with 50 g OGCT without regarding risk factors. Forty-seven percent of the women with GDM would have been missed in screening by risk factors only. Conclusions: In our population 50 g OGCT appears to identify a higher number of GDM than risk factor based screening. Combined with risk factor screening a few more cases of GDM would be found.