Uterine Fibroids

What are fibroids?

What causes fibroids?

Can fibroids become cancerous?

Who is at Risk for Uterine Fibroids?

What are the symptoms of fibroids?

What is the treatment for fibroids?

Return to Frequently Asked Questions Index

What are fibroids?

Uterine fibroids are nodules of smooth muscle cells and fibrous connective tissue that develop within the wall of the uterus (womb). Medically they are called uterine leiomyomata (singular: leiomyoma). Fibroids may grow as a single nodule or in clusters and may range in size from 1 mm to more than 20 cm (8 inches) in diameter. They may grow within the wall of the uterus or they may project into the interior cavity or toward the outer surface of the uterus. In rare cases, they may grow on stalks or peduncles projecting from the surface of the uterus. Fibroids are often referred to as tumors, but they are not cancerous.

What causes fibroids?

The cause of fibroid growth is not known. The vast majority of fibroids occur in women of reproductive age, and according to some estimates, they are diagnosed in black women two to three times more frequently than in white women. They are seldom seen in young women who have not begun menarche (menstruation) and they often stabilize or regress in women who have passed menopause.

Can fibroids become cancerous?

Fibroids are the most frequently diagnosed tumor of the female pelvis. It is important to know that these are benign tumors. They are not associated with cancer, they virtually never develop into cancer, and they do not increase a woman's risk for uterine cancer.

Who is at Risk for Uterine Fibroids?

No risk factors have been found for uterine fibroids other than being a female of reproductive age. However, some factors have been described that seem to be protective. In some studies (again, with small numbers of women) investigators found that as a group, women who have had two liveborn children have one-half the risk of having uterine fibroids compared to women who have had no liveborn children. It is not yet known whether having children actually protects a woman from developing fibroids or whether fibroids contributed to the infertility of women who had no children.

What are the symptoms of fibroids?

Most fibroids do not cause any symptoms and do not require treatment other than regular observation by a physician. Fibroids may be discovered during routine gynecologic examination or during prenatal care. Some women who have uterine fibroids, however, may experience symptoms such as excessive or painful bleeding during menstruation, bleeding between periods, a feeling of fullness in the lower abdomen, frequent urination resulting from a fibroid that compresses the bladder, pain during sexual intercourse, or low back pain. Reproductive symptoms such as infertility, recurrent spontaneous abortion, and early onset of labor during pregnancy have also been attributed to fibroids. In rare cases, a fibroid can compress and block the fallopian tube, preventing fertilization and migration of the ovum (egg); after surgical removal of the fibroid, fertility is generally restored.

What is the treatment for fibroids?

Until very recently, a woman with growing uterine fibroids was considered a candidate for hysterectomy (removal of the uterus). However, treatment by hysterectomy in a woman of reproductive age means that she will no longer be able to bear children and a hysterectomy may have other effects, both physical and psychological. A woman considering hysterectomy should discuss the pros and cons thoroughly with her physicians.

More and more, physicians are beginning to realize that uterine fibroids may not require any intervention or, at most, limited treatment. For a woman with uterine fibroids that are not symptomatic, the best therapy may be watchful waiting. Some women never exhibit any symptoms or have any problems associated with fibroids, in which case no treatment is necessary. For women who experience occasional pelvic pain or discomfort, a mild, over-the-counter anti-inflammatory or painkilling drug often will be effective. More bothersome cases may require stronger drugs available by prescription.

from The Office On Women's Health - US Department of Health and Human Services

Return to Frequently Asked Questions Index