 Dydrogesterone has been found to adequately induce bleeding within a sufficiently estrogen-primed endometrium.When estradiol levels are found to be low, dydrogesterone treatment is more effective when supplemented with estrogens.Endometriosis is a chronic disease which can cause severe, progressive, and at times, incapacitating dysmenorrhea, pelvic pain, dyspareunia and infertility.