Early gestational diabetes mellitus versus late gestational diabetes mellitus: Maternal and neonatal outcomes in a retrospective cohort in Asian Indians.

Objective: The concept of early gestational diabetes mellitus (EGDM) diagnosed in early pregnancy is rapidly evolving, but there is a need for more data. We sought to compare the pregnancy outcomes between EGDM and late gestational diabetes mellitus (LGDM) in South Indians.

Methods: This retrospective observational study was carried out in the Department of Obstetrics and Gynecology of a tertiary care institute at Puducherry in South India. The study included a total of 2401 singleton pregnant women aged more than 18 years with gestational diabetes (GDM) diagnosed using International Association of the Diabetes and Pregnancy Study Group criteria. The study participants were divided into EGDM and LGDM groups depending on whether GDM was diagnosed before or at or after 24 weeks of gestation.

Results: Early gestational diabetes mellitus was observed in 482 and LGDM in 1919 women. EGDM women had a significantly higher mean maternal age (28.5 vs. 27.5 years, P < 0.001), body mass index ≥25 kg/m² (68.4% vs. 62%, P < 0.001), fewer education years (11.9 vs. 12.2, P = 0.015), and a lower spontaneous conception rate (93.2% vs. 96.7%, P < 0.001). Need for combined insulin and metformin therapy (12% vs. 3.2%, adjusted relative risk (aRR): 2.19, 95% confidence interval [CI]: 1.57-3.05, P < 0.001), metformin alone therapy (35.9% vs. 18.5%, aRR: 1.85, 95% CI: 1.58-2.16, P < 0.001), preterm birth (13.9% vs. 6.5%, aRR: 2.25, 95%CI: 1.69-3.01, P < 0.001), and low birth weight babies (24.5% vs. 17.6%, aRR:1.35, 95%CI: 1.11-1.64, P = 0.002) were significantly higher in women with EGDM relative to LGDM.

Conclusion: Women with EGDM have significantly worse metabolic profile, greater need for pharmacotherapy, and worse fetal outcomes compared to LGDM.