Wen Q, et al. - Via performing two meta-analyses with different indicators, researchers examined the role of metformin in reducing the risk of gynecological cancers. The first meta-analysis comprising 7 studies including a total of 1,710,080 patients revealed that metformin reduces the risks significantly among Asians, for ovarian cancer, and for cervical cancer, but not in Caucasians or for endometrial cancer. Meanwhile, in 8 studies, another total of 8,335,332 cumulative follow-up years, person-years, were carried out revealing no statistical significance in general, and no difference in Caucasians, endometrial cancer or ovarian cancer. However, in the subgroup analyses, apparent significance results were noted in Asians and cervical cancer. These findings suggest the potential anticarcinogenic effect of metformin for gynecological cancers’ prevention, especially for Asians and cervical cancer.