Do pregnancy outcomes of women with false-positive early gestational diabetes mellitus differ from those of women with normal glucose tolerance?

Background: To investigate whether false-positive early gestational diabetes mellitus (GDM) women can be managed similarly as normal glucose tolerance (NGT) women.

Methods: This retrospective study was conducted at a tertiary care center in Japan. Pregnancy and neonatal outcomes of 67 singleton pregnancies with false-positive early GDM and 1774 singleton pregnancies with NGT who delivered after 22 weeks of gestation were compared. GDM was diagnosed according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria (patients having one or more of the following: fasting plasma glucose ≥ 92 mg/dL and a 75 g oral glucose tolerance test (OGTT) value ≥ 180 mg/dL at 1 h, or ≥ 153 mg/dL at 2 h). Pregnant women diagnosed with GDM in early pregnancy who did not meet the diagnostic criteria on the second OGTT were defined as having false-positive early GDM. Women with false-positive early GDM did not receive any therapeutic intervention during gestation.

Results: Maternal age, pre-pregnancy body mass index, and gestational weight gain were significantly higher in the false-positive GDM group than in the NGT group. No significant differences were found in pregnancy outcomes, including gestational age, birth weight, large for gestational age rate, and cesarean delivery rate. Except for a higher neonatal hypoglycemia rate in the false-positive early GDM group, no significant differences were found in neonatal outcomes.

Conclusions: There were no clinically significant differences between early GDM false-positive women exhibiting GDM patterns only during early pregnancy and NGT women. False-positive early GDM women can be managed similarly as NGT women, suggesting that World Health Organization diagnostic guidelines, applying the IADPSG criteria during early pregnancy, need revision.