Mediterranean Diet and Metformin Effects on Gestational Diabetes: A Review and Meta-Analysis of Randomized Controlled Trials

Abstract

Gestational diabetes (GD) is a common and deadly disorder with deleterious effects on both the mother and fetus. The current review assessed the role of the Mediterranean diet and metformin in the prevention of GD. The PubMed, Medline, and Google Scholar databases were searched for relevant articles, and the keywords metformin, Mediterranean diet, and gestational diabetes prevention were used with the proteans AND and OR. Out of the 252 articles retrieved, 48 full texts were assessed, and only nine articles fulfilled the inclusion and exclusion criteria. A data extraction sheet was used to collect the author's name, year of publication, country, methods of the study, risk reduction, odds ratio, relative risk, 95% CI, and P values. Three (33.3%) articles assessed the effectiveness of metformin on GD, and another six (66.7%) investigated the effects of the MedDiet on GD. The studies on metformin showed no reduction in GD (odds ratio, 1.07, 0.79–1.44, P value for overall effect=0.65, I2 for heterogeneity=3%, P value=0.36. Chi-square=2.07, and the mean difference=2), while studies on the MedDiet showed a reduction in gestational diabetes risk ((odds ratio, 0.49, -0.32–0.73, P value for heterogeneity =0.0004, heterogeneity, I =278%, P value for overall effect=0.0005, Chi-square=22.40 and mean difference=5. The Mediterranean diet was effective in the prevention of GD; however, metformin showed no significant risk reduction as an interventional measure.