Clinical experience with a screening program for gestational diabetes.

Screening for abnormal glucose metabolism was carried out in 2,077 pregnant women. Historical or clinical risk factors for gestational diabetes were present in 959 women (group 1). The remaining 1,118 patients composed group 2. A 50 gm oral glucose load and a 1-hour serum glucose determination with a threshold of 150 mg/dl were used as a glucose challenge screening test (GCT). Patients with an abnormal GCT underwent an oral glucose tolerance test (GTT). Group 1 patients underwent screening at the initial clinic visit or when the clinical risk factor was first recognized, with repeat screening at 28 to 32 weeks if the initial testing was normal. Group 2 patients were screened at 28 to 32 weeks. In group 1, 69 patients (7.2%) exhibited an abnormal GCT and 14 (1.5%) demonstrated an abnormal GTT. In group 2, 68 patients (6.1%) exhibited an abnormal GCT and 16 (1.4%) demonstrated an abnormal GTT. These incidences are not statistically different. The estimated costs per patient screened and per case of gestational diabetes detected were $4.75 and $328.96, respectively.