Maternal glucose metabolism and infant birth weight: a study in healthy pregnant women.

An intravenous glucose tolerance test (IVGTT) with serum insulin determinations was performed at week 37 of pregnancy in 52 healthy primiparae, selected to provide an increased variation in infant birth weight. A significant relationship was found between infant birth weight and both fasting blood glucose and t1/2 of glucose. Infant skinfold thickness, however, was not correlated independently to any of the parameters of the IVGTT. There was a significant correlation between maternal lean body mass and glucose metabolism, but this could not fully explain the relation between lean body mass and infant birth weight. Maternal fat mass was not significantly correlated to infant birth weight, though it was correlated with serum insulin levels. In the investigated population, fasting blood glucose, t1/2 of glucose, and maternal lean body mass accounted for 27% of the variation in infant birth weight.