Uterine fibroids are benign (non-cancerous) growths that develop from the muscle tissue of the uterus. They also are called leiomyomas or myomas. The size, shape, and location of fibroids can vary greatly. They may be present inside the uterus, on its outer surface or within its wall, or attached to it by a stem-like structure. A woman may have only one fibroid or many of varying sizes. A fibroid may remain very small for a long time and suddenly grow rapidly, or grow slowly over a number of years.
Fibroids are most common in women aged 30–40 years, but they can occur at any age. Fibroids occur more often in African American women than in white women. They also seem to occur at a younger age and grow more quickly in African American women.
There are four types of fibroids and these are:
Intramural Fibroids – These are located in the wall of the uterus. These are the most common types of fibroids.
Subserosal Fibroids – These are located outside the wall of the uterus. They can develop into pedunculated fibroids (stalks). Subserosal fibroids can become quite large.
Submucosal Fibroids – These are located in the muscle beneath the lining of the uterus wall.
Cervical Fibroids – These are located in the neck of the womb (the cervix).
Most fibroids don’t cause symptoms – only 10 to 20 percent of women who have fibroids require treatment. Depending on size, location and number of fibroids, they may cause:
– Heavy, prolonged menstrual periods and unusual monthly bleeding, sometimes with clots; this can lead to anemia.
– Pelvic pain and pressure.
– Pain in the back and legs.
– Pain during sexual intercourse.
– Bladder pressure leading to a frequent urge to urinate.
– Pressure on the bowel, leading to constipation and bloating.
– Abnormally enlarged abdomen.
It is unclear why fibroids develop, but several factors may influence their formation.
Estrogen and progesterone are the hormones produced by the ovaries. They cause the uterine lining to regenerate during each menstrual cycle and may stimulate the growth of fibroids.
Fibroids may run in the family. If your mother, sister, or grandmother has a history of this condition, you may develop it as well.
Pregnancy increases the production of estrogen and progesterone in your body. Fibroids may develop and grow rapidly while you are pregnant.
Fibroids that are attached to the uterus by a stem may twist and can cause pain, nausea, or fever. Fibroids that grow rapidly, or those that start breaking down, also may cause pain. Rarely, they can be associated with cancer. A very large fibroid may cause swelling of the abdomen. This swelling can make it hard to do a thorough pelvic exam.
Fibroids also may cause infertility, although other causes are more common. Other factors should be explored before fibroids are considered the cause of a couple’s infertility. When fibroids are thought to be a cause, many women are able to become pregnant after they are treated.
The first signs of fibroids may be detected during a routine pelvic exam. A number of tests may show more information about fibroids:
– Ultrasonography uses sound waves to create a picture of the uterus and other pelvic organs.
– Hysteroscopy uses a slender device (the hysteroscope) to see the inside of the uterus. It is inserted through the vagina and cervix (opening of the uterus). This permits the doctor to see fibroids inside the uterine cavity.
– Hysterosalpingography is a special X-ray test. It may detect abnormal changes in the size and shape of the uterus and fallopian tubes.
– Sonohysterographyis a test in which fluid is put into the uterus through the cervix. Ultrasonography is then used to show the inside of the uterus. The fluid provides a clear picture of the uterine lining.
Laparoscopy uses a slender device (the laparoscope) to help the doctor see the inside of the abdomen. It is inserted through a small cut just below or through the navel. The doctor can see fibroids on the outside of the uterus with the laparoscope.
Imaging tests, such as magnetic resonance imaging and computed tomography scans, may be used but are rarely needed. Some of these tests may be used to track the growth of fibroids over time.
Drug therapy is an option for some women with fibroids. Medications may reduce the heavy bleeding and painful periods that fibroids sometimes cause. They may not prevent the growth of fibroids. Surgery often is needed later. Drug treatment for fibroids includes the following options:
– Birth control pills and other types of hormonal birth control methods – These drugs often are used to control heavy bleeding and painful periods.
– Gonadotropin – releasing hormone (GnRH) agonists – These drugs stop the menstrual cycle and can shrink fibroids. They sometimes are used before surgery to reduce the risk of bleeding. Because GnRH agonists have many side effects, they are used only for short periods (less than 6 months). After a woman stops taking a GnRH agonist, her fibroids usually return to their previous size.
– Progestin – releasing intrauterine device – This option is for women with fibroids that do not distort the inside of the uterus. It reduces heavy and painful bleeding but does not treat the fibroids themselves.
Myomectomy is the surgical removal of fibroids while leaving the uterus in place. Because a woman keeps her uterus, she may still be able to have children. Fibroids do not regrow after surgery, but new fibroids may develop. If they do, more surgery may be needed.
Hysterectomy is the removal of the uterus. The ovaries may or may not be removed. Hysterectomy is done when other treatments have not worked or are not possible or the fibroids are very large. A woman is no longer able to have children after having a hysterectomy.