Comparative Study of Maternal and Fetal Outcomes in Patients with Gestational Diabetes Mellitus Treated with Insulin or Metformin

Abstract

Introduction: Gestational Diabetes Mellitus (GDM) is increasing globally, linked to obesity, age, and lifestyle changes. While insulin is the standard treatment, metformin is emerging as a safe, effective alternative. It improves insulin sensitivity and may reduce maternal and fetal complications. This study compares outcomes in GDM pregnancies treated with insulin versus metformin. Aims: To compare maternal and fetal outcomes in patients with gestational diabetes mellitus treated with Insulin or Metformin. Materials and Methods: This prospective observational comparative study was conducted from December 2022 to November 2023 at the OPD, antenatal, and postnatal wards of the Department of Obstetrics and Gynaecology, Chittaranjan Seva Sadan College of Obstetrics, Gynaecology and Child Health. A total of 106 pregnant women diagnosed with Gestational Diabetes Mellitus were included. The study aimed to compare maternal and fetal outcomes between insulin and metformin treatments. Results: In this study, insulin and metformin provided similar glycemic control in women with GDM. However, metformin was associated with significantly fewer neonatal complications such as hypoglycaemia (p=0.002), NICU admission (p=0.019), and respiratory distress (p=0.022). Neonatal birth weight was also lower in the metformin group (p=0.037), indicating a potentially safer neonatal profile. Conclusion: Untreated Gestational Diabetes Mellitus (GDM) can lead to serious maternal and neonatal complications. While insulin is the standard treatment, metformin has emerged as an effective and cost-efficient alter-native. Widely accepted in the West and increasingly used in India, metformin effectively controls blood sugar levels in GDM. It is also linked to fewer pregnancy complications and better neonatal outcomes. These findings support metformin as a safe and effective option for GDM management.