Uterine fibroids are tumors made of connective tissue and smooth muscle. They grow slowly within the wall of the uterus or attach to the uterine wall. Most fibroids are non cancerous, but in some rare cases they may become cancerous. This occurs in less than 1% of fibroids.

A uterine fibroid may be as small as a pea or as large as a grapefruit. As the fibroid grows, the uterus may become deformed or pushed aside. When the uterus is deformed or blocked by a growth, the resulting pressure may cause symptoms in the bladder or intestine, such as increased urination, constipation, or pain. If pregnant, fibroids can cause uterine pain and even increase the risk of miscarriage.

Other terms used for a uterine fibroid are leiomyoma or myoma of the uterus.

How do they occur?

The cause of uterine fibroids is known to be genetic in nature. In Caucasian women, the possibility of having fibroids is approximately 20-30%. In Black women, the incidence is as high as 50-70%. Growth of fibroids appears to be related to changes in estrogen levels. For example, pregnancy, use of high-estrogen birth control pills, and estrogen replacement therapy may speed the growth of fibroids. On the other hand, low dose birth control pills or when estrogen levels are low like during the menopause, fibroids tend to shrink.

Fibroids rarely occur in women younger than 20. They occur most frequently in women in their childbearing years. As a woman approaches menopause, these tumors usually shrink.

What are the symptoms?

Often there are no symptoms. When there are symptoms they may be:

painful menstrual periods
heavy menstrual bleeding with clots
more frequent or uncomfortable urination
backache
constipation
pelvic pain or pressure
infertility
miscarriage.

How are they diagnosed?

Fibroids are usually found during routine pelvic exams.

If you have severe menstrual symptoms or other pelvic problems, your health care provider may recommend an ultrasound scan or D&C (dilatation and curettage) to determine the cause of the problems.

How are they treated?

Most fibroids do not need treatment. Your health care provider will evaluate your condition and make a recommendation based on:

the amount of blood loss and pain during menstrual periods
the rate of growth of the fibroid
the absence or presence of cancer
your age, physical condition, and desire for more children.

For fibroids that require treatment, your doctor may suggest a myomectomy or hysterectomy. A myomectomy is a type of surgery used to remove the fibroids without having to remove the uterus. A myomectomy is usually done when the possibility of having children after the surgery is planned. In a hysterectomy, the surgeon removes the uterus. By removing the uterus, the possibility of fibroids returning is zero. A myomectomy can be technically more difficult than a hysterectomy and can lead to greater blood loss. The chance of fibroids returning is dependent on the number of fibroids a patient develops in the first place. It appears that the more fibroids a woman’s uterus develops, the more likely they are to return after a myomectomy.

Before you have a myomectomy or hysterectomy, you may be given a medication for 2 to 3 months to shrink the fibroid. This will make the operation easier to perform and often, decreases the amount of blood lost at the time of surgery. Furthermore, if a patient has developed anemia from heavy, recurrent menstrual cycles, medications can prevent menses while helping shrink the fibroids prior to surgery.

How long will the effects last?

Small fibroids that don't grow usually have no lasting effects. If you have symptoms caused by growing or enlarged fibroids, the symptoms will probably continue until the growths are removed surgically, or until they begin to shrink and disappear after menopause.

How can I take care of myself?

Call your health care provider if pain or bleeding continues to be a problem, or if you notice any worsening of your symptoms. In addition: • Take aspirin, acetaminophen, or ibuprofen for cramps and body aches. • Rest in bed when symptoms are worst. • Eat foods high in iron and take iron pills (if your health care provider recommends it) if you bleed heavily during your periods. • Put a heating pad at a low setting on your abdomen to help relieve cramps or pain. • Follow your health care provider's recommendation for follow-up visits to see if the fibroid is growing.

What can be done to help prevent uterine fibroids?

No sure way is known to prevent fibroids from developing or recurring.

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Robert B. McWilliams, MD Reproductive Endocrinology and Gynecology

Uterine Fibroids

Robert B. McWilliams, MD
Reproductive Endocrinology
and Gynecology