Efficacy of metformin combined with vitamin D in the treatment of polycystic ovarian syndrome: A meta-analysis

Polycystic ovary syndrome (PCOS), as an endocrine and metabolic disorder, affects approximately 6% -20% of women of childbearing age. This study aims to assess the therapeutic effects of Metformin combined with vitamin D in PCOS patients. Eight databases were searched to obtain randomized controlled trials, both domestically and internationally, on the effects of Metformin combined with vitamin D in patients with PCOS. Data analysis was performed using RevMan 5.3 software. Nine studies were ultimately included in this meta -analysis. Six studies reported the homeostatic model assessment for insulin resistance of the test group and the control group, which was significantly lower (SMD: -0.23; 95% Cl: -0.42,-0.04; P<0.05) than the control group, body mass index (BMI) (SMD: -1.86; 95% Cl: -2.77,-0.96; P<0.01), Serum 25 (OH) D (SMD: 14.28; 95% Cl: 12.26,16.29; P<0.01), testosterone (SMD: -0.11; 95% Cl: -0.15,-0.07; P<0.01) and regulated menstrual cycles (OR: 1.27; 95% Cl: 0.99,1.63; P=0.063). Our meta -analysis of nine trials demonstrates significant reductions in insulin resistance, BMI, and testosterone levels, along with increased serum vitamin D levels and improved menstrual cycle regulation after Metformin and vitamin D treatment. These findings suggest the potential of this combined therapy in managing the multifaceted aspects of PCOS.