Early gestational diabetes mellitus and the effect of metformin use on perinatal outcomes: a systematic review.

Introduction: The objective of this study was to perform a systematic review to assess whether metformin therapy in patients diagnosed with gestational diabetes mellitus (GDM) in early pregnancy is associated with improved perinatal outcomes. We searched Ovid MEDLINE, Scopus, and Cochrane library (inclusive of ClinicalTrials.gov) from inception through November 29, 2023. We included all randomized trials that assessed metformin use in early GDM.

Evidence acquisition: The 3665 results produced from the database searches were imported into Covidence, a systematic review screening tool, and duplicates were removed. The remaining 2731 citations were screened by title and abstract against predetermined inclusion and exclusion criteria by 2 independent reviewers with discrepancies resolved after group discussion. After screening was completed, 46 studies underwent full text review, with 1 study eligible for inclusion.

Evidence synthesis: The included study showed no difference in a composite adverse perinatal outcome between those diagnosed with early GDM and treated with metformin (59.3%) vs. placebo (57.1%).

Conclusions: There is a paucity of data regarding the management of early GDM and the lack of standardization in its definition for this condition.