Glycosylated hemoglobin (HbA1) assay as a test for detection and surveillance of gestational diabetes. A reappraisal.

Total glycosylated hemoglobin (HbA1) levels were measured in 96 gestational diabetics and 139 normal pregnant women in order to assess their usefulness in detection and monitoring of gestational diabetes. Different, although not significant, behaviour of HbA1 values was found in gestational diabetics and controls throughout pregnancy. Significantly higher (p less than 0.005) HbA1 values were found in gestational diabetics between the 24th and the 32nd week of gestation. In spite of this finding a low sensitivity in detecting gestational diabetes was confirmed. HbA1 values and OGTT parameters did not correlate. Delivery of a large-for-date (LGA) baby was not associated with higher HbA1 levels. Overlapping HbA1 levels were found in gestational diabetics and normal pregnant women. This study confirm the low predictive value of HbA1 assay in gestational diabetes.