Maternal hyperglycemia and the 100-g oral glucose tolerance test

To compare the characteristics of pregnant women with hyperglycemia according to the severity of glucose intolerance using the 100-g oral glucose tolerance test (OGTT) and to demonstrate the need to manage the condition of women with mild hyperglycemia.

In this retrospective cohort study, a total of 258 women at high risk of gestational diabetes (GDM) based on a positive 50-g oral glucose challenge test (OGCT) were classified into 0+, 1+, 2+, 3+, and 4+ groups according to the number of abnormal plasma glucose values on the 100-g OGTT. The clinical characteristics of the groups were compared.

The rates of advanced maternal age (≥ 35 years), multiparity, prior history of GDM, preterm birth, cesarean delivery, and elevated body mass index were all positively correlated with the number of abnormal plasma glucose values on the OGTT (p < 0.05 for all variables). After adjusting for confounding factors, the fasting plasma glucose levels predicted birth weight in 44.4%, 48.4%, and 58.6% of the women in the positive 50-g OGCT group, the 0+ group, and the 1+ group, respectively. Weight gain during pregnancy predicted birth weight in 42%, 44.6%, and 37.6% of the women in the positive 50-g OGCT group, the 0+ group, and the 2+ group, respectively (p < 0.001 in each case).

These data demonstrate that the detection and management of mild hyperglycemia below the current diagnostic criteria of GDM as well as GDM diagnosed using the 100-g OGTT are necessary for improving pregnancy outcomes.