title: Effect of advancing pregnancy on the glucose tolerance test and on the 50-g oral glucose load screening test for gestational diabetes.
abstract: To determine the validity of the 50-g, one-hour glucose screening test for gestational diabetes in relation to the duration of pregnancy, 101 patients from a high-risk population had the screening test in the first trimester and glucose tolerance tests (GTT) in the second and third trimesters. The sensitivity (88%) and specificity (82%) of the screening test were similar to values reported when the test is performed later in pregnancy. However, immediate follow-up GTTs in the second trimester revealed only 25% instead of 88% of the gestational diabetic patients uncovered by the positive screening tests. Guidelines for screening for gestational diabetes should include follow-up with a third-trimester GTT on all patients who have positive screening tests even in the presence of normal follow-up second trimester GTTs.
mesh_terms: D001786:Blood Glucose / Q000032:analysis*; D005188:False Negative Reactions; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood / Q000175:diagnosis*; D013997:Time Factors
chemical_list: D001786:Blood Glucose