Background
Gestational diabetes (GDM) in the third trimester is associated with adverse pregnancy outcomes and appropriate management improves these outcomes. There is comparatively little known about the outcomes of GDM diabetes in the first or second trimester. The objective of our study was to assess whether high-risk women with early HDM experienced worse maternal and neonatal outcomes compared to women with third trimester GDM and women who never developed GDM.
Methods
A total of 888 pregnant women who underwent a GTT prior to 20 weeks gestation were respectively recruited into the study. Women were grouped based on their GDM status: early GDM (diagnosis prior to 20 weeks 0 days gestation), late GDM (diagnosis after 20 weeks gestation) or no GDM. Outcomes were adjusted for maternal BMI, age, country of birth and parity.
Results
There was no difference in the obstetric composite between groups. Women with early and late GDM experienced greater incidence of the fetal composite compared to women with no GDM. Once broken down into its components, neonatal hypoglycaemia was found to be the significant contributing outcome within the composite. There was no difference in pre-eclampsia, PPH or HDU admission between groups. Women with early and late GDM experienced greater induction of labour compared to women with no GDM.
Conclusion
In this retrospective cohort, early diagnosis of DDM was not associated with adverse obstetric outcomes compared to women with normal glucose tolerance or late GDM after adjustment for maternal factors. This may be due to well-controlled GDM, or because in high-risk women, early GDM does not increase adverse outcomes. Rates of neonatal hypoglycaemia were increased, which may be an effect of increased diagnostic testing.