Risk for fetal malformations and unfavorable neonatal outcomes in early-onset gestational diabetes mellitus.

Background: Early-onset gestational diabetes mellitus (GDM) is diagnosed before the 24th gestational week. Since early GDM is associated with first trimester hyperglycemia, many clinicians treat these women as having pre-GDM. However, whether early GDM increases the risk for unfavorable pregnancy outcomes and particularly for fetal malformations to a greater extent than late-onset GDM were not studied sufficiently.

Markers for undiagnosed type 2 diabetes mellitus during pregnancy-A population-based retrospective cohort study.

Background: To examine possible markers for undiagnosed type 2 diabetes in early-onset gestational diabetes mellitus (GDM).

Methods: A population-based retrospective cohort study of women with GDM diagnosed prior to the 24th week, who delivered between 2005 and 2018, was conducted. The results of the 50-g glucose challenge test, 100-g oral glucose tolerance test, and the first available glycosylated hemoglobin (HbA1c) were examined as markers for type 2 diabetes diagnosed 6 to 12 weeks post pregnancy, which is suggestive of pregestational diabetes.