Early gestational diabetes(GDM) is associated with worse pregnancy outcomes compared to GDM diagnosed at 24-28weeks gestation despite early treatment.

BACKGROUND: Gestational Diabetes Mellitus (GDM) is associated with adverse pregnancy outcomes compared to women with normal glucose tolerance in pregnancy. The WHO recommends screening at 24-28weeks gestation for GDM. Women who are diagnosed before 24-28weeks gestation have a longer intervention period which may impact positively on pregnancy outcomes. AIM: This study aimed to examine pregnancy outcomes of women with GDM diagnosed <24weeks gestation compared to those diagnosed at 24-28 weeks in a large Irish cohort. METHODS: A retrospective cohort study of 1,471 pregnancies in women with GDM diagnosed using IADPSG criteria between September 2012- April 2016 was conducted. At GDM diagnosis, women were classified as early GDM <24 weeks or standard GDM 24-28weeks gestation. RESULTS: Women with early GDM had a significantly greater risk of pregnancy induced hypertension (12.4% v 5.3% p < 0.05), post-partum haemorrhage(8.7% v 2.4% p < 0.05) and post-partum glucose abnormalities (32% v15.6% p < 0.05).Their offspring had a greater risk of prematurity (10.9% v6.6% p < 0.05) stillbirth (1.4% v 0.5%p<0.05), large for gestational age 19.1% v 13.4% p < 0.05 and need neonatal intensive care30.7% v 22.1% p < 0.05 compared to offspring of women with standard GDM. Rates of C-section and prematurity were still higher in the early GDM group when the two groups where compared based on their postnatal OGTT. CONCLUSION: Early GDM women and their offspring are at greater risk of an adverse pregnancy outcome compared to those diagnosed at 24-28 weeks. In view of the abnormal post-natal glucose findings early GDM may reflect a more advanced state in diabetes pathogenesis.