Keywords
Insulin
Glucose intolerance
Pregnancy
Preeclampsia
Risk
Incidence
How to Cite
Abstract
Context: Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy, with most cases resolving after delivery. Adequate glycemic control is essential to reduce the risk of maternal and fetal complications. Historically, insulin has been the standard therapy, but recently, metformin has emerged as an alternative treatment.
Objectives: This meta-analysis aims to evaluate maternal outcomes in gestational diabetes mellitus patients treated with insulin versus metformin.
Methods: A systematic search was performed in PubMed, Embase, and Cochrane databases. Randomized controlled trials (RCTs) were included.
Results: Nineteen randomized controlled trials comprising 4,320 patients were analyzed, evaluating six maternal outcomes. Metformin was associated with a reduced risk of gestational hypertension (RR: 0.65; 95% CI: 0.49–0.87; P=0.77; I²=0%) and preeclampsia (RR: 0.57; 95% CI: 0.46–0.72; P=0.08; I²=39%). The risk of lower cesarean section rates (LCLS) was also reduced with metformin (RR: 0.92; 95% CI: 0.85–0.99; P=0.0002; I²=63%). Induced labor was less frequent with metformin (RR: 0.85; 95% CI: 0.76–0.95; P=0.01; I²=57%). The incidence of spontaneous vaginal delivery was higher in the metformin group (56.1%) (RR: 1.09; 95% CI: 1.03–1.17; P=0.002; I²=61%). No statistically significant difference was found in preterm birth rates between groups (RR: 0.91; 95% CI: 0.74–1.13; P=0.002; I²=60%).
Conclusion: This meta-analysis provides evidence supporting the use of metformin in the management of gestational diabetes mellitus, showing significant benefits in reducing rates of preeclampsia, gestational hypertension, and cesarean delivery, while also increasing spontaneous vaginal deliveries. Insulin may still be required in selected cases but appears to be associated with less favorable maternal outcomes.
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