Diabetes and Pregnancy

Endocrine Society Symposium
Wednesday, June 16, 2004
9:30-11:00 am

Reviewed by Aric Fader, PhD

The goals of this symposium were to review the clinical impact of diabetes and the potential effects that treatment can have on pregnant patients and their fetuses. Mean blood glucose is correlated with infant mortality. This finding is related to the fact that maternal glucose, but not insulin, crosses the placenta. Recent studies have demonstrated that oral metformin can cross the placenta and can result in lowering of lipids, although the effect on fetuses is not established.  Therefore, metformin is not considered a standard of care. However, treatment of insulin resistance is essential, and therefore glucose should be measured consistently throughout pregnancies. Data have shown that breast feeding can result in as much as a 5 mg decrease in blood glucose in mothers, as well as the fact that it reduces the risk for diabetes among their children. Maternal diabetes does increase the risk for birth defects. One recently conducted study showed that no birth defects occurred among newborn children whose mothers were patients with type 1 diabetes who had A1C normalized at roughly 5.5% beginning 6 weeks after initiation of pregnancy and maintained for the duration. The final conclusions from that study also revealed that delivery of insulin does not result in harm to fetuses.