Two thousand seventy-seven women attending a university-based prenatal clinic were screened for gestational diabetes. The patients were divided into two groups. Group 1 consisted of 959 patients with historic or clinical factors traditionally employed to identify patients as being at high risk for the occurrence of gestational diabetes. Group 2 consisted of the remaining 1118 patients. The O'Sullivan 50-g 1-h test, with an upper limit of normal for serum glucose of 150 mg/dl, was employed as the initial screening procedure. Patients with an abnormal screening test underwent a 3-h oral glucose tolerance test (GTT) with a 100-g load. The values recommended by the First American Diabetes Association Workshop-Conference on Gestational Diabetes were employed for interpretation. Group 1 patients underwent screening at their initial visit and again at 28 wk gestation. Group 2 patients underwent an identical screening sequence between 28 and 32 wk gestation. Cost analysis was performed.
The prevalences of positive screening tests were 7.2% and 6.1%, and the frequencies of abnormal GTTs were 1.5% and 1.4% among group 1 and group 2 patients, respectively. These rates were not statistically significantly different. Overall, 46.7% and 53.5% of the cases of gestational diabetes were identified among the patients with and without risk factors, respectively. The total cost of the screening program was $9869.00. The cost per patient screened and the cost per case of gestational diabetes identified were $4.75 and $328.96, respectively. These results reemphasize the inadequacy of screening only those patients with traditional risk factors for gestational diabetes and demonstrate the feasibility of implementing a program of universal glucose screening among, a large obstetric population. The observed cost compares favorably with screening tests employed for other diseases during pregnancy.