Glycohemoglobins in Normal and Diabetic Pregnancy

ABSTRACT

Glycosylated hemoglobin (HbA₁) concentration was measured in 155 pre- and 30 postpartum patients to study its correlation with glucose metabolism and perinatal outcome in patients suspected of carbohydrate intolerance during pregnancy. Though the mean HbA₁ values were significantly higher in gestational diabetics compared to normal pregnant controls, the large overlap between HbA₁ levels of diabetic patients and levels in the of normal range, make HbA₁ an unreliable screening device for diabetes. However, if the HbA₁ level was elevated in patients suspected of carbohydrate intolerance, but who had a normal glucose tolerance test, the perinatal outcome in terms of macrosomia and neonatal metabolic abnormalities was similar to that of the group with gestational diabetes. HbA₁ measurements should be obtained in these women, and, if elevated, maternal and fetal surveillance is recommended. HbA₁ level is not a useful predictor of birthweight, though may be of value as a postpartum screen for unrecognized diabetes and may help discriminate between a constitutionally large but otherwise normal newborn and a large infant of a diabetic mother.