Uterine fibroids are non-cancerous tumors that develop within or attach to the wall of the uterus, a female reproductive organ. Alternative name include leiomyomas, fibromyomas, and myomas.
Causes, Incidence, and Risk Factors
Uterine fibroids are the most common pelvic tumor. The cause of uterine fibroid tumors is unknown. Oral contraceptives and pregnancy lower the risk of developing new fibroid tumors.
Fibroids may be present in 15 - 20% of women in their reproductive years -- the time after starting menstruation for the first time and before menopause. Fibroids may affect 30 - 40% of women over age 30. Fibroids occur 2 to 3 times more frequently in African-American women than in Caucasian women.
The growth of a fibroid depends on the hormone estrogen. As long as a woman with fibroids is menstruating, the fibroids will probably continue to grow, usually slowly. Fibroids rarely affect females younger than 20 or who are postmenopausal.
Fibroids begin as small seedlings that spread throughout the muscular walls of the uterus. They can be so tiny that you need a microscope to see them. However, they can also grow very big. They may fill the entire uterus, and may weigh several pounds. Although it is possible for just one fibroid to develop, usually there is more than one.
Sometimes, a fibroid hangs from a long stalk, which is attached to the outside of the uterus. Such a fibroid is called a pedunculated fibroid. It can become twisted and cause a kink in blood vessels feeding the tumor. This type of fibroid may require surgery.
It is possible to have fibroids and have no symptoms. If you have symptoms, they can include the following:
A sensation of fullness or pressure in lower abdomen
Pelvic cramping or pain with menstrual periods
Abdominal fullness, gas
Increased urinary frequency
Heavy menstrual bleeding (menorrhagia), sometimes with the passage of blood clots
Sudden, severe pain due to the twisted stalk of a pedunculated fibroid
Signs and Tests
A pelvic examination may reveal an irregularly shaped, lumpy, or enlarged uterus. Frequently, diagnosis by pelvic exam is reliable. In some cases, diagnosis of fibroids is difficult, especially in obese women. Fibroid tumors have been mistaken for ovarian tumors, inflammation of the fallopian tubes, and pregnancy.
A transvaginal ultrasound or pelvic ultrasound may be performed to confirm the findings.
A D&C or a pelvic laparoscopy may be necessary to rule out potentially cancerous conditions.
Treatment depends on the severity of symptoms, the woman's age, whether or not she is pregnant, the desire for future pregnancies, her general health, and characteristics of the fibroids. Some women may just require monitoring of the fibroid. This requires pelvic exams or ultrasounds periodically to monitor the growth of the fibroid.
Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naprosyn may be recommended for women who have cramps or pain with menstruation. Birth control pills (oral contraceptives) may be used to help control heavy periods and to stop the fibroid from growing. Iron supplements may be given to prevent anemia in women with heavy periods.
In some cases, hormonal therapy involving drugs such as injectable Depo Leuprolide is prescribed to shrink the fibroids. This medicine reduces the production of the hormones estrogen and progesterone. The hormones create a situation in the body that is very similar to menopause. Side effects can be severe and may include hot flashes, vaginal dryness, and loss of bone density.
Hormone treatment may last several months. Fibroids will begin to grow again as soon as treatment stops. In some cases, hormone therapy is used for a short period of time before surgery or when the woman is expected to reach menopause soon.
Hysteroscopic resection of fibroids (an outpatient surgical procedure) may be needed for women with fibroids growing inside 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 at preventing the need for major surgery. The method stops the blood supply that makes fibroids grow. The long-term effects of this procedure are still unknown, and the safety of pregnancy after this procedure is questionable.
A myomectomy is a surgical procedure to remove just the fibroids. It is frequently the chosen treatment for premenopausal women who want to have children, because it usually can preserve fertility. Another advantage of a myomectomy is that it controls pain or excessive bleeding that some women with uterine fibroids have..
If all else fails, hysterectomy (removal of the uterus) may be necessary
Prior to menopause, fibroids are likely to grow slowly.
As a general rule, fibroids don't interfere with fertility. However, a tumor sometimes blocks the fallopian tubes and prevents sperm from reaching and fertilizing eggs. In some cases, fibroids may prevent a 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.
Cesarean section may be needed for delivery since fibroid tumors can occasionally block the birth canal or cause the baby to be positioned incorrectly. After menopause, new fibroids rarely develop and those already present usually shrink to their pre-pregnancy size.
Fibroids may cause infertility. They may also cause premature delivery.
Severe pain or excessively heavy bleeding with fibroids may require emergency surgery.
In rare cases, cancerous changes may occur. These usually take place after menopause. The most common warning sign is rapid growing of a fibroid. A definitive diagnosis is usually not made until the time of surgery.
Calling Your Doctor
Call your doctor if gradual changes in your menstrual pattern occur (heavier flow, increased cramping, bleeding between periods), or if fullness or heaviness develops in your lower abdomen. Frequently there is associated pressure or discomfort and occasionally interference with normal urination frequency.
This posting is based on information from the National Institutes of Health.
Share the health.
Deborah White, MD, MBA