Plasma glucose and plasma insulin values during the 75g glucose tolerance test (75g GTT) in pregnancy.

Abstract

Summary : The 75 g GTT was performed on 722 pregnant women to clarify the glucose tolerance during pregnancy. The results were as follows : (1) Plasma glucose values after 75g GTT were the same in category A (with potential diabetes or glycosuria) before and after 28 weeks of pregnancy, but for women in categories B (without potential diabetes and glycosuria) and C (excluding the neonatal complications in category B), the plasma glucose values were higher during or after 28 weeks of pregnancy than before the 28th week. (2) The plasma glucose after glucose loading was higher in category A than in category B or C, but there was no difference between category B and C. (3) The plasma insulin values in category B were the same before and after 28 weeks of pregnancy; but for women in categories A and C, the values were significantly higher after 28 weeks of pregnancy.(4) The incidence of a low insulinogenic index was 12.1% in category A, which was significantly higher than the indexes for categories B and C. These results may be useful to establish the normal limit of glucose values after 75g glucose loading during pregnancy.