Adenomyosis is a condition in which tissue that normally lines the uterus (endometrium) also grows within the muscular walls of the uterus. This is most likely to happen late in your childbearing years and after you’ve had children.
Adenomyosis isn’t the same as endometriosis — a condition in which the uterine lining becomes implanted outside the uterus — although women with adenomyosis often also have endometriosis. The cause of adenomyosis remains unknown, but the disease typically disappears after menopause. For women who experience severe discomfort from adenomyosis, there are treatments that can help, but hysterectomy is the only cure.
Although adenomyosis can be quite painful, the condition is generally harmless. Learn more about adenomyosis, including its signs and symptoms, when you should see a doctor and what the best treatment might be for you.
In some women, adenomyosis is “silent” — causing no signs or symptoms — or only mildly uncomfortable. But other women with adenomyosis may experience:
- Heavy or prolonged menstrual bleeding
- Severe cramping or sharp, knife-like pelvic pain during menstruation (dysmenorrhea)
- Menstrual cramps that last throughout your period and worsen as you get older
- Pain during intercourse
- Bleeding between periods
- Passing blood clots during your period
Your uterus may increase to double or triple its normal size. Although you might not know if your uterus is enlarged, you may notice that your lower abdomen seems bigger or feels tender.
The cause of adenomyosis isn’t known. Some experts believe that adenomyosis results from the direct invasion of endometrial cells into the uterine walls. Sometimes an operation, such as a Caesarean section (C-section), can make this invasion of cells easier. Other experts speculate that adenomyosis originates within the uterine walls (myometrium) from endometrial tissue deposited there when the uterus was first forming in the female fetus.
Another theory suggests a link between adenomyosis and childbirth — that an inflammation of the uterine lining (endometritis) during the postpartum period might cause a break in the normal boundary of the cells of the uterus. Regardless of how adenomyosis develops, its growth depends on the circulating estrogen in a woman’s body. When estrogen disappears at menopause, adenomyosis resolves.
Women who have had prior uterine surgery, such as a C-section or fibroid removal, are at greater risk of adenomyosis. Also, adenomyosis is more common among women who have given birth to at least one child.
Your doctor may suspect adenomyosis based on:
- Signs and symptoms
- A pelvic examination, which reveals an enlarged uterus that’s tender to touch
- Ultrasound imaging of the uterus
- Magnetic resonance imaging (MRI) of the uterus
In rare instances, your doctor may take a biopsy of endometrial tissue — a sample of cells from your uterine lining for testing — to verify that your abnormal uterine bleeding isn’t associated with any other serious condition. However, such a biopsy won’t help your doctor confirm a diagnosis of adenomyosis. The only way to establish the diagnosis of adenomyosis is to examine uterine tissue using a microscope after removal of the uterus (hysterectomy).
Many women have other uterine diseases that cause signs and symptoms similar to adenomyosis, making adenomyosis more difficult to diagnose. Such conditions include fibroid tumors (leiomyomas), uterine cells growing outside the uterus (endometriosis) and growths in the uterine lining (endometrial polyps). Your doctor may diagnose adenomyosis only after he or she determines there are no other causes for your signs and symptoms.
Although a blood test won’t indicate whether you have adenomyosis, your doctor may suggest testing to assess your menstrual blood loss.
Adenomyosis usually resolves after menopause, so treatment may depend on how close you are to that stage of life.
Treatment options for adenomyosis include:
- Anti-inflammatory drugs. If you’re nearing menopause, your doctor may have you try anti-inflammatory medications, such as ibuprofen (Advil, Motrin, others), to control the pain. By starting an anti-inflammatory medicine two to three days before your period begins and continuing to take it during your period, you can reduce menstrual blood flow in addition to relieving pain.
- Hormone therapy. Controlling your menstrual cycle through combined estrogen-progestin oral contraceptives, hormone-containing patches or vaginal rings may lessen the heavy bleeding and pain associated with adenomyosis. Progestin-only contraception, such as an intrauterine device containing progestin or a continuous-use birth control pill, often leads to amenorrhea — the absence of your menstrual periods — which may provide relief.
- Hysterectomy. If your pain is severe and menopause is years away, your doctor may suggest surgery to remove your uterus (hysterectomy). Removing your ovaries isn’t necessary to control adenomyosis.
Although not harmful, the pain and excessive bleeding associated with adenomyosis can have a negative effect on your lifestyle. You may find yourself avoiding activities that you previously enjoyed because you have no idea when or where you might start bleeding. Painful periods can cause you to miss work or school and can strain relationships. Recurring pain can lead to depression, irritability, anxiety, anger and feelings of helplessness. That’s why it’s important to seek medical evaluation if you suspect you may have adenomyosis.
Unlike endometriosis, adenomyosis doesn’t usually affect fertility. However, if you experience prolonged, heavy bleeding, chronic anemia may result.