To consider the mentionedstudy and association between the increased levelof peritoneal leptin with endometriosis and unexplainedinfertility, it can be proposed that leptinstimulates toxic factors in peritoneal fluid and alsodecreases the quality of oocyte in endometriosis.It should be noted that the cause of unexplainedinfertility needs to be identified with new advancesin infertility treatment and leptin is likely to beconsidered as one of the involved factors. Here, LEP is linked to Infertility.