title: Screening for carbohydrate intolerance in pregnancy: a comparison of two tests and reassessment of a common approach.
abstract: The usefulness of glycosylated hemoglobin as a prenatal screening test for carbohydrate intolerance was studied in 806 consecutive subjects by correlating glycosylated hemoglobin to 1-hour post-50 gm Glucola plasma glucose levels, 3-hour oral glucose tolerance tests, and perinatal and maternal outcomes. Sixty-seven subjects whose 1-hour post-50 gm Glucola plasma glucose levels were greater than or equal to 150 mg/100 ml underwent 3-hour oral glucose tolerance tests; 12 were diagnostic of carbohydrate intolerance. Compared to carbohydrate-tolerant control subjects, gravid patients with carbohydrate intolerance were older, more obese, had higher 1-hour post-50 gm Glucola plasma glucose and glycosylated hemoglobin levels, and infants with increased birth weight percentiles, depressed 5-minute Apgar scores, and an increased incidence of shoulder dystocia and perinatal mortality. Three of 10 carbohydrate-intolerant patients who were evaluated post partum were found to have previously undiagnosed diabetes. Division of measurements of 1-hour post-50 gm Glucola plasma glucose and glycosylated hemoglobin into normal, borderline, and suspicious groups demonstrated a reduction in discriminatory capability of glycosylated hemoglobin as compared to the 1-hour post-50 gm Glucola plasma glucose. We conclude that laboratory screening for carbohydrate intolerance should be a standard element of the prenatal evaluation; gravid patients found to have carbohydrate intolerance should be reevaluated post partum to rule out overt diabetes, and the 1-hour post-50 gm Glucola plasma glucose test is the preferred means of routine screening for carbohydrate intolerance in pregnancy.
mesh_terms: D000328:Adult; D001034:Apgar Score; D001724:Birth Weight; D001786:Blood Glucose / Q000032:analysis*; D050260:Carbohydrate Metabolism; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D007744:Obstetric Labor Complications; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood*; D011254:Pregnancy in Diabetics / Q000097:blood*
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin