Reduced short-term variability of fetal heart rate in association with maternal hyperglycemia during pregnancy in insulin-dependent diabetic women.

The differential index, which describes the short-term component of fetal heart rate variability, and maternal blood glucose levels were measured 109 times in 19 insulin-dependent diabetic mothers in the second half of gestation. An abnormal differential index was observed more often with maternal hyperglycemia (11/45) than with normoglycemia (5/64). A significant negative linear correlation was found between the differential index and the blood glucose level of the mother.