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.
Adenomyosis
Adenomyosis happens when tissue that lines the uterus grows into the muscle wall of the uterus. During a menstrual cycle, the tissue thickens, breaks down and bleeds. Painful periods with heavy bleeding can result.
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.
Women’s health topics – straight to your inbox
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.
