Influence of maternal and fetal glucokinase mutations in gestational diabetes.

We report 2 insulin-treated pregnancies in a mother with hyperglycemia resulting from a glucokinase gene mutation. The inheritance of a glucokinase mutation in 1 child reduced his intrauterine growth (birth weight less than first percentile) by reducing fetal insulin secretion. We discuss the implications for obstetric management of patients with glucokinase mutations.