METTL3 and Infertility: Our present study demonstrated that m6A and METTL3 were upregulated in the mid-secretory phase of endometria from women with endometriosis-related infertility compared to those in fertile women without endometriosis, and that the upregulation of METTL3 impaired the decidualization of endometrial stromal cells, thus contributing to defective uterine receptivity and poor embryo implantation.