Endometriosis
Surgery is more effective than medicinal intervention for addressing infertility associated with endometriosis. Surgery attempts to remove endometrial tissue and preserve the ovaries without damaging normal tissue. In-vitro fertilization (IVF) procedures are effective in improving fertility in many women with endometriosis.
Dienogest
Dienogest is described as "special" progestogen, possessing low or moderate antigonadotropic efficacy but strong or very strong endometrial efficacy. Specifically in relation to endometrial activity, dienogest is said to be one of the strongest progestogens available. The high endometrial activity of dienogest underlies its ability to stabilize the menstrual cycle when combined with either ethinylestradiol or estradiol valerate in birth control pills, and also its use in the treatment of endometriosis. The combination of most other progestins with estradiol as birth control pills failed due to a high incidence of irregular menstrual bleeding. This is a property that ethinylestradiol does not share with estradiol, because of its resistance to metabolism in the endometrium and hence its greater relative effects in this part of the body. In contrast to other progestins, due to its high endometrial efficacy, the combination of dienogest with estradiol valerate in birth control pills is able to prevent breakthrough bleeding, and is uniquely able to treat heavy menstrual bleeding. The absence of withdrawal bleedings, otherwise known as "silent menstruations", also may occur.