Assessment and management of pregnancies complicated by pregestational and gestational diabetes mellitus.

Diabetes mellitus is a commonly encountered medical complication of pregnancy that affects more than 100,000 pregnancies annually. The discovery of insulin and numerous scientific advances, including both fetal heart rate and glucose monitoring, dramatically improved the outlook for women with diabetes and their offspring. However, despite these recent advances, women with diabetes and their infants still remain at higher risk for a number of complications. Pregnancy has frequently been characterized as having a diabetogenic effect on normal carbohydrate metabolism, as evidenced by hyperglycemia and hyperinsulinemia in response to feeding. This leads to gestational diabetes in 2% to 3% of women and a worsened metabolic state in women with insulin-dependent diabetes mellitus. Since the availability of nutrients for the fetus is primarily dependent on the maternal metabolic state, these aberrations in fuel metabolism are believed to result in a host of perinatal complications, including diabetic embryopathy. In fact, the frequency of congenital anomalies is increased among infants of women with diabetes; they are responsible for approximately 40% of all perinatal deaths. Recent evidence suggests that normalization of blood glucose levels coupled with contemporary management strategies can reduce the frequency of congenital anomalies as well as improve maternal and neonatal outcomes. However, to impact on the congenital anomalies, euglycemia must begin in the preconceptual period and continue throughout organogenesis. Preconception counseling and intensive therapy regimens remain the focus of management programs targeted at women with diabetes.