The tissue that normally lines the inside of the uterus is called the endometrium. In some women endometrium grows within the muscle cells (myometrium) of the uterus. When this happens a woman has a condition called adenomyosis. This condition is similar to endometriosis where the endometrium is found outside the uterus but with adenomyosis, the endometrium is limited to the uterine musculature. This misplaced tissue responds to the hormones of the menstrual cycle and bleeds each month in the same way the lining of the uterus responds to hormones. However, if the tissue is not within the cavity of the uterus, the blood shed from the tissue has no way to leave the body. When the tissue bleeds, cysts, adhesions, and scar tissue form and the area around the endometrium thickens.

How does it occur?

Why some women develop adenomyosis is not known. There are many theories, but none of them explains all cases. One theory suggests that in some women the barrier between the endometrium and myometrium, the barrier that normally prevents invasion of endometrial glands is compromised allowing invasion to occur. Adenomyosis most commonly affects women between the ages of 35 and 50 years. It is almost always associated with a past history of multiple childbirths.

How common is it?

Adenomyosis is a condition that is considerably more common than is generally appreciated, occurring in 15 – 25% of women in the reproductive age group. Microscopic analysis of hysterectomy specimens discloses an even higher incidence of the condition, as high as 65%, suggesting that many patients experience no symptoms from the process.

What are the symptoms?

Some women have no symptoms. If symptoms occur they may include:

• Abnormal or heavy menstrual flow

• Back or flank pain before or during the menstrual period

• Progressively worsening painful menstrual cramps

• Painful intercourse around the time of menses

• Pelvic pain, especially before or during the menstrual period

How is it diagnosed?

First, the doctor will ask you about your symptoms. You will need a pelvic exam to check for cysts or nodules or any abnormal tenderness or thickening in your pelvic area. Usually, the doctor will detect a tender uterus on palpation of the uterus during his/her pelvic exam. The closer to the woman’s menses, the more tender is the exam. Often, the diagnosis is suspected by using an ultrasound exam that reveals enlarged venous (blood vessel) sinuses within the uterine musculature. Tenderness over these areas during a transvaginal ultrasound exam can also be used to confirm the diagnosis short of microscopic confirmation after hysterectomy. The diagnosis is confirmed by microscopic examination of the uterus after a hysterectomy. Many symptoms and signs may suggest the process but the pathologist examining the uterine muscles after removal of the uterus determines confirmation.

Is it associated with other uterine disorders?

Adenomyosis can be associated with other uterine disorders. More than 80% of women with adenomyosis have another pathologic process in the uterus. Many of these women have fibroids (benign smooth muscle cell tumors of the uterus), some have associated endometriosis, and others have endometrial polyps (excess growth of the endometrial lining).

How is it treated?

In a patient with symptomatic adenomyosis, hysterectomy with preservation of the ovaries when appropriate is the treatment of choice. It is a disease that can get more severe as you grow older. Treatments short of hysterectomy include birth control pills, progesterone therapy, and Lupron Depo. These options exist to lessen the symptoms and complications. The treatment depends on the severity of the symptoms, the degree of adenomyosis, your age, and your plans for childbearing.

How long will the effects last?

No treatment has been found yet that is 100% effective except for hysterectomy. All current therapy offers at least some relief from the symptoms but not a cure. If your uterus is removed, you can never become pregnant.

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Robert B. McWilliams, MD Reproductive Endocrinology and Gynecology

Adenomyosis

Robert B. McWilliams, MD
Reproductive Endocrinology
and Gynecology