Uterine fibroids Health Article

Definition

Uterine fibroids are noncancerous (benign) tumors that develop in the uterus (womb), a female reproductive organ.

Alternative Names

Leiomyoma; Fibromyoma; Myoma; Fibroids

Causes, incidence, and risk factors

Uterine fibroids are the most common pelvic tumor. As many as 1 in 5 women may have fibroids during their childbearing years (the time after starting menstruation for the first time and before menopause).

Fibroids usually affect women over age 30. They are rare in women under 20, and often shrink and cause no symptoms in women who have gone through menopause. They are more common in African Americans than Caucasians.

The cause of uterine fibroid tumors is unknown. However, fibroid growth seems to depend on the hormone estrogen. As long as a woman with fibroids is menstruating, a fibroid will probably continue to grow, usually slowly.

Fibroids can be so tiny that you need a microscope to see them. However, they can grow very large. They may fill the entire uterus, and may weigh several pounds. Although it is possible for just one fibroid to develop, usually there are more than one.

Fibroids are often described by their location in the uterus:

• Myometrial -- in the muscle wall of the uterus
• Submucosal -- just under the surface of the uterine lining
• Subserosal -- just under the outside covering of the uterus
• Pendunculated -- occurring on a long stalk on the outside of the uterus or inside the cavity of the uterus

Symptoms

More common symptoms of uterine fibroids are:

• Abdominal fullness, gas, or constipation
• Bleeding between periods
• Increase in urinary frequency
• Heavy menstrual bleeding (menorrhagia), sometimes with the passage of blood clots
• Menstrual periods that may last longer than normal
• Pelvic cramping or pain with periods
• Sensation of fullness or pressure in lower abdomen
• Pain during intercourse

Note: There are often no symptoms.