Hyperinsulinaemia and normal glucose tolerance tests in pregnancy

Hyperinsulinaemia is a condition present during late pregnancy, returning to normal after delivery. Since some pregnant women are not able to adapt themselves to this high insulin secretion they could become gestational diabetics. We attempt here to describe the insulin metabolism during late pregnancy according to the women's levels of fasting insulin at six months postpartum. Sixty-seven pregnant women underwent a glucose tolerance test at weeks 20, 30 and 36 of pregnancy and at 6 months postpartum. Glucose and insulin values were measured. The women were classified as follows: group one, women who at 6 months postpartum had fasting insulin levels above the mean (13.5/dl) and group two, who fasting levels were below the mean. The significant difference between the groups was found at all points of the insulin curve at six months postpartum, but not for the glucose curve. During pregnancy, a difference in insulin was also found for weeks 20;30 and 36 but not for the glucose. Group one, whose insulin level were higher since week 20, presented with hyperinsulinaemia, while group two behaved as described in the literature, i.e., secreting more insulin as the pregnancy advanced. Women of group one are at major risk to develop diabetes mellitus, type II later in life (AU)