Endometriosis

Endometriosis is usually a long-lasting (chronic) disease. Some women have no symptoms or problems. Others develop mild to severe symptoms or infertility. There is no way to predict whether endometriosis will get worse, will improve, or will stay the same until menopause.

Endometrial growths (implants) can develop on the ovaries or fallopian tubes, the outer surface of the uterus, the bowels, or other abdominal organs. In rare cases, it can affect other organs and structures in the body.

Endometriosis implants go through the same growing, breaking down, and bleeding that the uterine lining (endometrium) goes through with each menstrual cycle. This is why endometriosis pain may start as mild discomfort a few days before the menstrual period, and usually goes away by the time the period ends. But if an implant grows in a sensitive area, it can cause constant pain or pain during certain activities, such as sex, exercise, or bowel movements.

Endometriosis symptoms often get better during pregnancy, and they usually disappear after menopause. These are times when estrogen levels are low, which slows or stops endometriosis growth.³ For most women, endometriosis symptoms also improve with hormonal treatments that lower estrogen levels.

Ovarian cancer risk is higher in women with endometriosis.² This type of ovarian cancer is most commonly seen in women older than 60.

• Birth control pill use for 5 or more years lowers ovarian cancer risk.⁴
• Danazol, sometimes used to treat endometriosis, may increase ovarian cancer risk.⁵

Infertility and endometriosis

Between 20% and 40% of women who are infertile have endometriosis (some have more than one possible cause of infertility).¹ Experts do not fully understand how endometriosis causes infertility. Explanations include the following:⁶

• Scar tissue (adhesions) may form at the sites of implants and change the shape or function of the ovaries, fallopian tubes, or uterus. Scar tissue can:
  • Block the fallopian tubes, preventing or slowing the movement of eggs (ova) from the ovaries to the uterus.
  • Surround the ovaries, preventing eggs from moving to the fallopian tubes.
• The endometrial implants may change the chemical and hormonal makeup in the fluid that surrounds the organs in the abdominal cavity (peritoneal fluid). Such a change can:
  • Interfere with or prevent the release of eggs from the ovaries (ovulation). Some women with endometriosis do not ovulate.
  • Interfere with the fallopian tubes' ability to help an egg move toward the uterus.
  • Prevent a pregnancy in the uterus.
  • Change the menstrual cycle.

Infertility caused by endometriosis can sometimes be successfully treated with surgery, fertility drug treatment and insemination, in vitro fertilization, or a combination of these.

Ovarian endometrioma

A common complication of endometriosis is the development of a cyst on an ovary. This blood-filled growth is called an ovarian endometrioma, or an endometrial cyst. Endometriomas can be as small as 1 mm or more than 10 cm (3.9 in) across.³

Ovarian endometriomas may not cause specific symptoms. The symptoms may be the same as those of endometriosis, since the endometrioma may not be the only site of endometriosis. Your health professional may be able to feel an endometrioma during a gynecologic exam. A large endometrioma is usually surgically removed.