Point: Oral Hypoglycemic Agents Should Not Be Used to Treat Diabetic Pregnant Women

Abstract

Studies in pregnancy indicate that the most important glucose concentration throughout the day is the peak postprandial glucose response; i.e., it is the highest blood glucose of the day, not the average, that predicts risk of untoward effects. The Diabetes in Early Pregnancy (DIEP) Study was a multicenter, case-controlled trial of type 1 diabetic women compared with healthy control women throughout pregnancy. Along with the primary objective of relating maternal glucose to risk of spontaneous abortions and malformations, they also studied the relationship between maternal postprandial glucose concentrations and risk of neonatal macrosomia (1). The DIEP Study identified 28.5% of infants from diabetic mothers who were above the 90th percentile of infant birth weight. Birth weight correlated positively with first-trimester maternal fasting blood glucose and A1C. When adjusted for fasting blood glucose and A1C, the 1-h postprandial maternal blood glucose concentration in the third trimester was an even stronger predictor of infant birth weight and fetal macrosomia. In addition, they reported that the risk of macrosomia is a continuum. They showed that any postprandial glucose peak was associated with an increased risk of macrosomia above the 10% risk seen in the general population. Combs et al. (2) confirmed the findings of the DIEP Study and added the observation that elevated postprandial glucose was associated with an increased rate of macrosomia when higher maternal postprandial glucose concentrations were observed between weeks 29 and 32 of gestation. In a study of gestational diabetic women who failed a trial of diet and thus required insulin therapy, De Veciana et al. (3) described improved fetal outcome with less risk of neonatal hypoglycemia, macrosomia, and Caesarean delivery in women with gestational diabetes mellitus (GDM) when the women were managed by controlling 1-h postprandial glucose concentrations as opposed to action only based on preprandial glucose concentrations. …