Adenomyosis

Date Updated: 09/11/2025

Overview

Adenomyosis (ad-uh-no-my-O-sis) is a condition that affects the uterus. The uterus is the hollow, pear-shaped organ where a baby grows during pregnancy. When someone has adenomyosis, the tissue that lines the inside of the uterus grows into the muscle wall of the uterus. This tissue is called endometrial tissue.

During a menstrual cycle, endometrial tissue thickens, breaks down and bleeds. Endometrial tissue that's present in the uterus wall also thickens, breaks down and bleeds. This can make the uterus get bigger. The condition can be painful, and periods can be heavy.

Experts aren't sure what causes adenomyosis, but symptoms often go away after menopause. Hormonal treatments can help with pain and heavy bleeding. Surgery to remove the uterus, called hysterectomy, can cure adenomyosis.

Symptoms

In some people, adenomyosis causes no signs or symptoms. Or it causes only mild discomfort. For others, adenomyosis symptoms can include:

Heavy or long-lasting periods.
Severe cramping or sharp pelvic pain during periods.
Pelvic pain that doesn't go away.
Painful sex.
A larger uterus, which might cause tenderness or pressure in the lower stomach area.

When to see a doctor

You should see a healthcare professional if you have heavy periods that last a long time or have severe cramping during your periods that get in the way of your daily activities.

Causes

The exact cause of adenomyosis isn't known, but theories about possible causes include:

Endometrial cells growing into the muscle wall of the uterus, possibly from cuts made in the uterus during surgery.
Endometrial tissue deposited in the uterus during fetal development.
Inflammation of the lining of the uterus after childbirth.
Bone marrow stem cells in the uterine muscle that transform and act like endometrial cells.
Retrograde menstruation, where blood during a period flows back from the uterus into the fallopian tubes and pelvic cavity instead of out of the body. This also may be a cause of a related condition called endometriosis.

No matter how adenomyosis develops, its growth depends on the female reproductive hormone estrogen.

Risk factors

Risk factors for adenomyosis include:

Prior uterine surgery, such as C-section, fibroid removal, or dilation and curettage.
Childbirth.
Middle age.

Most cases of adenomyosis occur in women in their 40s and 50s. Adenomyosis in women at this age could be related to more years of estrogen exposure compared with younger women. But current research suggests that the condition might also be common in younger women.

People with adenomyosis sometimes have other uterine conditions too. Adenomyosis often is present in women with endometriosis and uterine fibroids. When uterine conditions happen together, diagnosis may be harder because symptoms are often similar.

Complications

Heavy bleeding during periods from adenomyosis could lead to anemia. Anemia occurs when there aren't enough healthy red blood cells to carry oxygen to the body's tissues. This can make you feel tired and short of breath and cause other health problems.

Pain and bleeding associated with adenomyosis also can disrupt your lifestyle. You might avoid activities you've enjoyed in the past because you're in pain. Or you might worry about heavy bleeding that soaks through your underwear and clothes.

Adenomyosis may lead to problems during pregnancy, such as miscarriage, preterm birth and babies who are small for their gestational age. Adenomyosis also may be linked to infertility, but more studies are needed.

Diagnosis

Adenomyosis shares similar symptoms with other uterine conditions. These conditions include uterine fibroids, endometriosis and endometrial polyps. Uterine fibroids are tumors that aren't cancer that grow in the uterus. Endometriosis happens when cells similar to the lining of the uterus grow outside the uterus. Endometrial polyps are growths in the uterine lining.

Sometimes it's hard for healthcare professionals to know for certain that someone has adenomyosis. You may find out you have the condition only after you've been checked for other possible causes for your signs and symptoms. Testing for adenomyosis may include:

A pelvic exam. During this exam, a healthcare professional checks whether the uterus has gotten bigger or feels tender.
Ultrasound. An exam called transvaginal ultrasound uses a narrow device, called a transducer, that's inserted into the vagina. The transducer puts out sound waves to create images of the uterus, ovaries and other pelvic organs.
Magnetic resonance imaging. Magnetic resonance imaging also is called MRI. This test helps detect signs of adenomyosis or other possible conditions of the uterus.

In some cases, a healthcare professional might do an endometrial biopsy. A biopsy is a procedure to remove a sample of tissue for testing in a lab. The lab checks the tissue sample to make sure you don't have a more serious condition, such as cancer. But an endometrial biopsy won't help confirm a diagnosis of adenomyosis.

The only way to be certain of a diagnosis of adenomyosis is to look at the uterus after hysterectomy.

Treatment

The symptoms of adenomyosis often go away after menopause. Treatment might depend on how close you are to that stage of life.

Treatment options for adenomyosis include:

Anti-inflammatory drugs. Your healthcare professional might recommend an anti-inflammatory medicine, such as ibuprofen (Advil, Motrin IB, others). You may start taking the medicine 1 to 2 days before your period begins and continue taking it during your period. This can lessen menstrual blood flow and help relieve pain.
Hormone medicines. Combined estrogen-progestin birth control pills or hormone-containing patches or vaginal rings might ease heavy bleeding and pain. Progestin-only contraception, such as an intrauterine device, or continuous-use birth control pills often cause amenorrhea, which might provide some relief. Amenorrhea is when menstrual periods stop.
Hysterectomy. If you have a lot of pain and heavy bleeding with periods, and no other treatments have worked, your healthcare professional might suggest surgery to remove the uterus. Removing the ovaries isn't needed for adenomyosis.

Self care

To find some relief from the pelvic pain and cramping related to adenomyosis, you might try to:

Soak in a warm bath.
Use a heating pad on your lower stomach area.
Take an anti-inflammatory medicine, such as ibuprofen (Advil, Motrin IB, others).

Preparing for your appointment

For adenomyosis, you may have an appointment with either the healthcare professional who provides your primary care or a gynecologist. A gynecologist is a doctor who specializes in conditions that affect the female reproductive system.

What you can do

Before your appointment, make note of:

Your symptoms and when they began.
All medicines, vitamins and other supplements you take, including how much you take.
Medical information, such as details about your periods and whether you've given birth.
Questions to ask your healthcare professional.

Some questions you may want to ask include:

What's the most likely cause of my symptoms?
Are there any other possible causes?
Do I need to have any testing done?
Are there medicines I can take to help with my symptoms?
Do I need surgery?
Could my condition affect whether I can get pregnant?

Don't hesitate to ask other questions as they occur to you during your appointment.

What to expect from your doctor

You may be asked questions such as:

What symptoms do you have?
When do you usually have symptoms?
How bad are your symptoms?
When was your last period?
Could you be pregnant?
Are you using a birth control method? If so, which one?
Do your symptoms seem to be related to your periods?
Does anything seem to make your symptoms better?
Does anything make your symptoms worse?