The cause of fibroid tumors of the uterus is unknown. However, it is suggested that fibroids may enlarge with estrogen therapy (such as oral contraceptives) or with pregnancy.

Their growth seems to depend on regular estrogen stimulation, showing up only rarely before the age of 20 and shrinking after menopause. As long as a woman with fibroids is menstruating, the fibroids will probably continue to grow, although growth is usually quite slow.

Fibroids can be microscopic, but they can also grow to fill the uterine cavity, and may weigh several pounds. Uterine fibroids are the most common pelvic tumor and they may be present in 15 to 20% of reproductive-age women, and 30 to 40% of women over 30.

Fibroids occur 3 to 9 times more frequently in African-American women than in Caucasian women.

It is possible for a single fibroid to develop although normally there are a number of them, which begin as small seedlings spread throughout the muscular walls of the uterus.

They slowly enlarge and become more nodular, frequently intruding into the cavity of the uterus or growing out beyond the normal boundary of the uterus. Rarely, a fibroid will hang from a long stalk attached to the outside of the uterus. This is called a pedunculated fibroid.

• Sensation of fullness or pressure in lower abdomen
• Pelvic cramping or pain with periods
• Abdominal fullness, gaseous
• Increase in urinary frequency
• Heavy menstrual bleeding (menorrhagia), sometimes with the passage of blood clots, sometimes resulting in anemia (a low blood count)
• Sudden, severe pain (a pedunculated fibroid twists causing the blood vessels feeding the tumor to kink) -- hospitalization and surgery may be needed in this instance

Note: There are often no symptoms.

A pelvic examination reveals an irregularly shaped, lumpy, or enlarged uterus. Frequently, this diagnosis is reliable, however, on occasion, diagnosis is difficult, especially in obese women. Fibroid tumors have been mistaken for ovarian tumors, inflammatory processes of the tubes, and pregnancy.

A transvaginal ultrasound or pelvic ultrasound may be performed to confirm the findings.

A D and C procedure or a pelvic laparoscopy may be necessary to rule out other, potentially malignant, conditions.

Methods of treatment depend on the severity of symptoms, age, pregnancy status, desire for future pregnancies, general health, and characteristics of the fibroid(s). Treatment may consist of simply monitoring the fibroids, specifically their rate of growth, with periodic pelvic exams or ultrasound.

Nonsteroidal anti-inflammatory medications (like ibuprofen or naprosyn) may be recommended for lower abdominal cramping or pain with menses. Iron supplementation will help to prevent anemia in women with heavy periods. These methods are usually sufficient in pre-menopausal women.

Hormonal treatment, involving drugs such as injectable Depo Leuprolide, causes fibroids to shrink, but can also causes significant side effects. This method is sometimes used for short treatment periods before surgical procedures or when menopause is imminent.

The hormones produce an environment in the body that is very similar to that of menopause, with associated side effects like hot flashes, vaginal dryness, and loss of bone density.

The treatment lasts several months and during this time the reduction in estrogen concentration allows the fibroids to shrink. Fibroids will begin to enlarge as soon as treatment stops.

Hysteroscopic resection of fibroids (an outpatient surgical procedure) may be appropriate for women with fibroids largely growing within the uterine cavity. In this procedure, a small camera and instruments are inserted through the cervix into the uterus to remove the fibroid tumors.

Uterine artery embolization is a new procedure aimed to prevent the need for major surgery for uterine fibroids. Small catheters are placed through veins in the groins and advanced to the arteries that supply the uterus with blood.

Materials are then injected to block these arteries permanently. The decreased blood supply to the uterus may prevent further growth of the fibroids and may cause them to shrink. The long-term effects of this procedure are still unknown, and the safety of pregnancy after this procedure is questionable.

A myomectomy, which is a surgical procedure to remove just the fibroids, is frequently the chosen treatment for pre-menopausal women who want to bear more children, as it usually can preserve fertility.

Another advantage of a myomectomy is that it controls pain or excessive bleeding that some women with uterine fibroids experience. However, a myomectomy often cannot remove very small fibroids that may grow and cause symptoms again in the future.

A total hysterectomy, which involves removal of the uterus, is a curative option that is often chosen by older women.

Prior to menopause, fibroids are likely to grow slowly. Women with known fibroids, who choose to have children, may be counseled to become pregnant earlier in adulthood.

As a general rule, fibroids don't interfere with fertility. However, rarely a tumor will block the fallopian tubes and prevent sperm from reaching and fertilizing the egg. In some cases, fibroids may prevent the fertilized egg from implanting in the uterine lining. However, proper treatment may restore fertility.

After a pregnancy is established, existing fibroids may grow due to the increased blood flow and estrogen levels. These usually return to their original size after the baby has been delivered.

Most women are able to carry their babies to term, but some of them end up delivering prematurely because there is not enough room in the uterus to sustain full term.

Cesarean section may be needed for delivery since fibroid tumors can occasionally block the birth canal or cause the baby to be positioned abnormally. After menopause, new fibroids rarely develop and those already present usually shrink.

Fibroids may cause infertility because they can interfere with conception or implantation. They may cause premature delivery because of decreased area within the uterus. Severe pain or excessively heavy bleeding with fibroids may necessitate emergency surgery.

Rarely, malignant changes may occur. These usually take place in postmenopausal women. The most common warning sign is rapid enlargement of a fibroid and definitive diagnosis is usually not made until the time of surgery.