Diabetic pregnancy: is it time to enjoy the fruits of our labors?

Before insulin therapy, the diabetic pregnancy was a consummate disaster for mother and child. Maternal mortality approached 30%, and survival of the offspring was uncommon (1). Although in 1988 diabetic mothers and their offspring clearly benefit from better perinatal care, many of the improvements shown to decrease maternal and perinatal morbidity have yet to be incorporated into the routine health care of all diabetic women. Far too often, a successful outcome is simply assumed to be a viable newborn. This view overlooks the long-term health of the mother and her offspring, both of which depend on quality care before conception and in the years after delivery. Congenital anomalies in the offspring of diabetic women are two to three times that of nondiabetic women (2); however, recent experience indicates that this rate can be reduced to that of the general population. The reduction is accomplished by tight glucose control during the first trimester or period of organogenesis (3). Neonatal macrosomia continues to be a source of morbidity for both mother and child. Shoulder dystocia, brachial plexus injury, and bone fracture are encountered more commonly during vaginal delivery of the macrosomic fetus (4). In light of this, some authors recommend primary cesarean section in all pregnant diabetic women suspected of having a macrosomic fetus (>4000 g; 5). Thus, macrosomia contributes to the increased rate of cesarean section (33-69 vs. 20% among nondiabetic mothers; 6,7) and may be thought of as yet another consequence of less than optimal diabetic control. A better solution would be the prevention of fetal ma-crosomia. Tight control may be necessary during early gestation because near-normal glycemia late in pregnancy has been shown to have a poor correlation with neonatal weight (8). In this issue, Mazze and Langer (p. 263) report that early identification and treatment of women with diabetes resulted in a decrease from 34 to 15% in the incidence of macrosomia and an impressive cesarean section rate of only 16%. What is not understood by many is the rigorous degree of glycemic control needed throughout pregnancy to achieve these results. The goal is fasting and pre-prandial blood glucose concentrations in the range of 4-5 mM and 2-h postprandial values <6.7 mM, representing the upper limits of normal glucose concentrations in the pregnant nondiabetic woman (9). This impressive degree of glucose control is realistic and effective not just for women attending tertiary centers but also for women included …