Adenomyosis (ad-en-oh-MY-oh-sis) is a condition where endometrial glands and supporting tissues are found in the muscular wall of the uterus where it would not occur normally. This extra tissue causes an enlarged uterus and painful, heavy periods. Adenomyosis is usually found in women in their 40s and 50s.

Adenomyosis is closely related to endometriosis. Endometriosis is a disease where the cells that normally line the inside of the uterus and are shed during menstruation, become implanted and grow outside of the uterus. Adenomyosis may also be found in women who have already been diagnosed with endometriosis. It usually occurs in the posterior wall of the uterus.

Adenomyosis is also called: endometriosis internal, uterine endometriosis, endometriosis of the uterus, and internal endometriosis.

Adenomyosis and cancer

Adenomyosis is a benign condition. Research shows that having it does not increase risks of developing cancer. However, both adenomyosis and cancer could coexist within the same endometrial tissue.

Signs and symptoms

The most common symptoms are:

  • abnormal uterine bleeding
  • large uterus (uterus is often 2-3 times the normal size)
  • pelvic pain during menstruation

Symptoms usually go away after menopause occurs. A hysterectomy will make symptoms go away.

Note: In many cases, the woman may not have any symptoms.

How does Adenomyosis occur?

Adenomyosis occurs when the old tissue and blood cannot escape the uterine muscle and flow out of the cervix as part of normal menses.


Currently, the exact cause of adenomyosis is unknown.

Treatment options

Some of the treatment options are: Hysterectomy and pain medication.

Risk factors for developing adenomyosis include:

  • prior uterine surgery, such as a C-section or fibroid removal
  • childbirth


Prolonged, heavy bleeding during your periods can cause chronic anemia, which causes fatigue and low levels of iron.