Uterine Fibroids




Uterine fibroids are among the most common tumors in women. These noncancerous growths of the uterus may appear during your childbearing years. Also called fibromyomas, leiomyomas or myomas, uterine fibroids aren't associated with an increased risk of uterine cancer and almost never develop into cancer. Most of the time, uterine fibroids aren't harmful.

As many as three out of four women have uterine fibroids, but most are unaware of them as they often cause no signs or symptoms. Your doctor may discover them incidentally during a pelvic exam or prenatal ultrasound. Fibroids cause problems for about one in four women, most frequently during their 30s or 40s.

Fibroids can require emergency treatment if they cause sudden, sharp pelvic pain. But this is rare. In general, fibroids cause no problems and seldom require treatment. Medical therapy and surgical procedures can shrink or remove fibroids if they cause discomfort or troublesome symptoms.

Signs and Symptoms

When signs and symptoms of uterine fibroids are present, the most common include: Rarely, a fibroid can cause acute pain when it outgrows its blood supply. Deprived of nutrients, the fibroid begins to die. Byproducts from a degenerating fibroid can seep into surrounding tissue, causing pain and fever. A fibroid that hangs by a stalk inside or outside the uterus (pedunculated fibroid) can trigger pain by turning on its stalk.

Fibroid location influences your signs and symptoms. Fibroids that grow into the inner cavity of the uterus (submucosal fibroids) are thought primarily responsible for prolonged, heavy menstrual bleeding. Fibroids that project to the outside of the uterus (subserosal fibroids) can press on your bladder or ureters, causing you to experience urinary symptoms. If fibroids bulge from the back of your uterus, they can press either on your rectum, causing constipation, or on your spinal nerves, causing backache.

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Causes

Uterine fibroids develop from the smooth muscular tissue of the uterus (myometrium). A single cell reproduces repeatedly, eventually creating a pale, firm, rubbery mass distinct from neighboring tissue. Fibroids range in size from seedlings, undetectable by the human eye, to bulky masses that can distort and enlarge the uterus. They can be single or multiple, in extreme cases expanding the uterus so much that it reaches the rib cage.

Doctors don't know why fibroids occur, but research and clinical experience point to several factors:
  • Genetic alterations. Many fibroids contain alterations in genes that code for uterine muscle cells.
  • Hormones. Estrogen and progesterone, two reproductive hormones produced by the ovaries that stimulate development of the uterine lining in preparation for a possible pregnancy, appear to promote the growth of fibroids. Fibroids contain more estrogen and estrogen receptors than do normal uterine muscle cells.
  • Other chemicals. Substances that help the body maintain tissues, such as insulin-like growth factor, may affect fibroid growth.
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Risk Factors

There are few known risk factors for uterine fibroids, other than being a woman of reproductive age. Heredity probably plays a role. If your mother or sister had fibroids, you're at increased risk of also developing them. Black women are more likely to have fibroids than are women of other racial groups. In addition, black women have fibroids at younger ages, and they're also likely to have more or larger fibroids.

Research examining other potential risk factors has been inconclusive. Although some studies have suggested that obese women are at higher risk of fibroids, other studies have not shown a link. In addition, limited studies once suggested that women who take oral contraceptives and athletic women may have a lower risk of fibroids, but later research failed to establish this connection. Researchers have also looked at whether pregnancy and giving birth may have a protective effect, but results remain unclear.

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Screening and Diagnosis

Your doctor will likely determine if uterine fibroids are in fact the cause of your symptoms. Disorders with similar signs and symptoms include:
  • Adenomyosis. In this condition, glands normally located in the uterine lining penetrate the muscular wall of your uterus. Pain results when displaced glandular tissue develops during your menstrual cycle and then attempts to slough off during menstruation. Abnormal bleeding results when the tissue builds up and blood seeps from the muscle. Treatment is surgery or hormonal therapy.

  • Hormonal dysfunction. Abnormal hormone signals that accompany lack of ovulation can cause heavy bleeding and a thickened uterine lining.

  • Uterine (endometrial) polyps. These growths, usually noncancerous (benign), extend from the lining of your uterus. They may cause heavy menstrual bleeding, spotting after your menstrual period or spotting not related to menstruation.
Your doctor will likely ask about your signs and symptoms and perform a pelvic exam. He or she may order a complete blood count (CBC) to determine if you have iron deficiency anemia because of chronic blood loss. Your doctor might order blood tests to rule out bleeding disorders and to determine the levels of reproductive hormones produced by your ovaries.

To look for other causes of abnormal bleeding, such as uterine cancer, your doctor might remove a sample of cells from the lining of your uterus for laboratory analysis. This procedure is called an endometrial biopsy. Your doctor can perform it in his or her office. Anesthesia usually isn't necessary.

Your doctor may need images of your uterus to detect the fibroids. Ultrasound - a painless exam that uses sound waves to obtain a picture of your uterus - maps and measures fibroids. A doctor or technician moves the ultrasound device (transducer) over your abdomen (transabdominal) or places it inside your vagina (transvaginal) to obtain images of your uterus. Transvaginal ultrasound provides more detail because the probe is closer to the uterus. Transabdominal ultrasound visualizes a larger anatomic area.

Your doctor may order other imaging studies, such as:
    Hysterosonography. This diagnostic technique uses an ultrasound probe to obtain images of the uterine cavity.
    Hysterosalpingography. This technique uses a dye to highlight the uterine cavity and fallopian tubes on X-ray images.
    Hysteroscopy. Your doctor inserts a small, lighted telescope called a hysteroscope through your cervix into your uterus. The tube releases a gas or liquid to expand your uterus, allowing your doctor to examine the walls of your uterus and the openings of your fallopian tubes. A hysteroscopy can be performed in your doctor's office.
Other imaging techniques that may be necessary to diagnose fibroids include computerized tomography (CT) and magnetic resonance imaging (MRI). Your doctor may order an MRI to diagnose adenomyosis.

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Complications

Although fibroids usually aren't dangerous, they can cause discomfort and may lead to complications such as anemia from heavy blood loss. Fibroids usually don't interfere with conception and pregnancy, but they can occasionally affect fertility. They may distort or block your fallopian tubes, or interfere with the passage of sperm from your cervix to your fallopian tubes. Submucosal fibroids may prevent implantation and growth of an embryo. Pregnant women with fibroids are at slightly increased risk of miscarriage, premature labor and delivery, abnormal fetal position, and separation of the placenta from the uterine wall.

In rare instances, fibroid tumors can grow out of your uterus on a stalk-like projection. If the fibroid twists on this stalk, you may develop a sudden, sharp, severe pain in your lower abdomen. If so, seek medical care right away. You may need surgery.

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Treatment

There's no single best approach to treating uterine fibroids. Many treatment options exist.

Watchful waiting
If you're like most women with uterine fibroids, you have no signs or symptoms. In your case, watchful waiting (expectant management) could be the best course. Fibroids aren't cancerous. They rarely interfere with pregnancy. They usually grow slowly and tend to shrink after menopause when levels of reproductive hormones drop. This is the best treatment option for most women with uterine fibroids.

Hysterectomy
This operation - the removal of the uterus - remains the only proven permanent solution for uterine fibroids. But hysterectomy is major surgery. It ends your ability to bear children, and if you elect to have your ovaries removed also, it brings on menopause and the question of whether you'll take hormone replacement therapy.

Medications Medications for uterine fibroids target hormones that regulate your menstrual cycle, treating symptoms such as heavy menstrual bleeding and pelvic pressure. They don't eliminate fibroids, but may shrink them. Medications include:
  • Gonadotropin-releasing hormone (Gn-RH) agonists. To trigger a new menstrual cycle, your hypothalamus - an area at the base of your brain that acts as a control center for your body - manufactures gonadotropin-releasing hormone (Gn-RH). The substance travels to your pituitary gland, a tiny gland also located at the base of your brain, and sets in motion events that stimulate your ovaries to produce estrogen and progesterone. Medications called Gn-RH agonists (Lupron, Synarel, others) act at the same sites that Gn-RH does. But when taken as therapy, a Gn-RH agonist produces the opposite effect to that of your natural hormone. Estrogen and progesterone levels fall, menstruation stops, fibroids shrink and anemia often improves.

  • Androgens. Your ovaries and your adrenal glands, located above your kidneys, produce androgens, the so-called male hormones. Given as medical therapy, androgens can relieve fibroid symptoms. Danazol, a synthetic drug similar to testosterone, has been shown to shrink fibroid tumors, reduce uterine size, stop menstruation and correct anemia. However, occasional unpleasant side effects such as weight gain, dysphoria (state of feeling depressed, anxious or uneasy), acne, headaches, unwanted hair growth and a deeper voice, make many women reluctant to take this drug.

  • Other medications. Oral contraceptives or progestins can help control menstrual bleeding, but they don't reduce fibroid size. Nonsteroidal anti-inflammatory drugs (NSAIDs), which are not hormonal medications, are effective for heavy vaginal bleeding unrelated to fibroids, but they don't reduce bleeding caused by fibroids.
Myomectomy In this surgical procedure, your surgeon removes the fibroids, leaving the uterus in place. If you want to bear children, you might choose this option.

Uterine artery embolization
Small particles injected into the arteries supplying the uterus cut off blood flow to fibroids, causing them to shrink. This technique is proving effective in shrinking fibroids and relieving the symptoms they can cause. Advantages over surgery include:
    No incision
    Shorter recovery time
Complications may occur if the blood supply to your ovaries or other organs is compromised.

Focused ultrasound surgery
MRI-guided focused ultrasound surgery (FUS), approved by the Food and Drug Administration in October 2004, is a newer treatment option for women with fibroids. Unlike other fibroid treatment options, FUS is noninvasive and preserves your uterus.

This procedure is performed while you're inside of a specially crafted MRI scanner that allows doctors to visualize your anatomy, and then locate and destroy (ablate) fibroids inside your uterus without making an incision. Focused high-frequency, high-energy sound waves are used to target and destroy the fibroids. A single treatment session is done in an on- and off-again fashion, sometimes spanning several hours. Initial results with this technology are promising, but its long-term effectiveness is not yet known.

Variations of myomectomy - in which uterine fibroids are destroyed surgically without actually removing them - include:
  • Myolysis. In this procedure, an electric current destroys the fibroids and shrinks the blood vessels that feed them.
  • Cryomyolysis. This approach uses liquid nitrogen to "freeze" the fibroids.
The safety, effectiveness and recurrence of risks of myolysis and cryomyolysis have yet to be determined.
  • Endometrial ablation. This treatment involves removal of the lining of your uterus, either ending menstruation or reducing your menstrual flow. Endometrial ablation is effective in stopping abnormal bleeding, but doesn't affect fibroids outside the interior lining of the uterus.
You may have seen on the Internet, or in books focusing on women's health, alternative treatments, such as certain dietary recommendations or homeopathy (practicing stress reduction techniques and taking herbal preparations). More research is necessary to determine whether dietary practices or other methods can help prevent or treat fibroids. So far, there's no scientific evidence to support the effectiveness of these techniques.

Because fibroids aren't cancerous and usually grow slowly, you have time to gather information before making a decision about treatment. The option that's right for you depends on a number of factors, including the severity of your signs and symptoms, your plans for childbearing, how close you are to menopause, and your feelings about surgery. Before making a decision, consider the pros and cons of all available treatment options in relation to your particular situation. Remember, most women don't need any treatment for uterine fibroids.

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Prevention

Although researchers continue to study the causes of fibroid tumors, little scientific advice is available on how to prevent them. Preventing uterine fibroids may not be possible, but you can take comfort in the fact that only a small percentage of these tumors require treatment.

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Information obtained from National Institute of Health
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