Major congenital anomalies in infants and glycosylated hemoglobin levels in insulin-requiring diabetic mothers.

Glycosylated hemoglobin levels were obtained in 133 diabetic pregnancies. Nongestational diabetic mothers delivered of infants with major congenital anomalies had significantly higher glycosylated hemoglobin levels than the remaining nongestational diabetic mothers (P less than .001). The higher a mother's glycosylated hemoglobin level, the higher her risk of having a severely affected infant was. The positive predictive value for a nongestational diabetic mother having an infant with severe congenital anomalies was 26% if the glycosylated hemoglobin level was greater than or equal to 11%, 40% if the level was greater than or equal to 12%, and 56% if the level greater than or equal to 13%. However, high glycosylated hemoglobin levels in insulin-requiring gestational diabetic mothers were not predictive of major congenital anomalies.