Uterine fibroids

Related Terms

Endometrial ablation, fibromyomas, focused ultrasound surgery, hysterectomy, intramural fibroids, leiomyomas, leiomyosarcoma, myomas, myomectomy, pedunculated fibroids, submucosal fibroids, subserosal fibroids, tumors, uterine fibroid embolization, uterine leiomyomata, uterus.

Background

Uterine fibroids are tumors, or growths, made up of muscle and other tissues that grow in the uterus. They may develop in the uterine wall, inside the lining of the uterus, or outside of the uterus. They occur in 20-25% of women of childbearing age, and up to 80% of women will suffer from fibroids at some point in their lives. A single fibroid may develop or several may develop in groups. Fibroids range in size from less than one inch to larger than the size of a grapefruit. Other names for fibroids are uterine leiomyomata, fibromyomas, leiomyomas, and myomas.
Many women with fibroids do not experience any symptoms and are unaware that they have fibroids. However, about one in four women may have heavy bleeding, pain, and urinary problems that require treatment. Fibroids are almost always benign (not harmful) and very rarely develop into cancer. Fewer than 0.1% of fibroid cases become cancerous. Other complications may include infertility, pregnancy problems, and anemia.
Any woman can develop fibroids; they are most common among African American women. The cause is unknown and there are no known ways to prevent them.
Fibroids are classified based on their location in the uterus and can be submucosal, intramural, subserosal, and pedunculated. Symptomatic fibroids can be treated with medications, surgeries, and other procedures. The most invasive surgery available, called a hysterectomy, completely removes the uterus and is the only treatment that completely prevents fibroids from growing back. One-third of hysterectomies in the United States are due to uterine fibroids.

Signs and symptoms

General: It is estimated that about 80-90% of women who have fibroids do not have any symptoms. However 10-20% may experience menstrual problems, pain, urinary/bowel problems, and a feeling of fullness in the lower abdomen. The size, location, and number of fibroids also plays a role in the types of symptoms a woman experiences.
Menstrual problems: A woman with fibroids may have heavy bleeding and periods that are more painful and longer than normal. Fibroids may cause blood to stay in the uterus long enough for clots to form, which may then cause severe menstrual cramping. Patients with fibroids may experience bleeding in between periods. These symptoms are more common with fibroids that grow inside the uterus (submucosal fibroids).
Pain: Pain and pressure may be felt in the pelvis (lower abdomen) of women with fibroids. The pain is sometimes caused when the fibroid starts to die off due to lack of nutrients and its byproducts are absorbed into the tissues. Some women experience pain in their backs or legs as well as pain during sexual intercourse. Bleeding during sexual intercourse has also been reported.
Urinary/bowel problems: If the fibroids are located on the outside of the uterus (subserosal fibroids), they may put pressure on the bladder and may cause urinary and bladder problems. Some women feel like they have to urinate frequently and some have urinary incontinence, which is the inability to hold urination. Other women may have constipation or develop hemorrhoids if the fibroids are putting pressure on the rectum.

Diagnosis

General: Most fibroids are found during routine pelvic exams. The doctor is usually able to feel if the uterus is an irregular shape or size, which may indicate a fibroid. Imaging tests and a hysteroscopy are two ways to find fibroids and look at them in more detail.
Imaging: An ultrasound uses sound waves to create a picture when a wand-like device (called a transducer) moves over the abdomen (transabdominal). A doctor may place the transducer inside the vagina (transvaginal) to get a more detailed picture of the uterus and the fibroids.
Hysterosonography is another type of ultrasound in which saline is used in the uterine cavity in order to obtain inside images of the uterus. This ultrasound can be used when a transvaginal ultrasound is not sufficient.
A hysterosalpingography is a type of X-ray image that uses a dye to highlight the uterus and fallopian tubes. A doctor uses this if it is suspected that the woman is infertile because it shows fibroids and whether the fallopian tubes are open.
Other imaging tests that are used include X-rays, which use radiation to see inside the body; computerized tomography (CT) scans, which take many pictures at different angles; and magnetic resonance imaging (MRI), which uses magnets and radio waves to produce a picture.
Hysteroscopy: A hysteroscopy is a procedure where a hysteroscope, or small telescope, is put into the uterus through the vagina. There is a tube that releases gas or liquid to expand the uterus to look at the uterine walls and the fallopian tubes. Unlike the other procedures, this procedure can be done at the doctor's office.

Complications

General: Most fibroids are benign and may not cause any symptoms or complications. Some women may have problems with pregnancy. Pregnancy complications, like symptoms, depend on the size, location, and number of fibroids a woman has. It is even less likely that the fibroids will become cancerous.
Anemia: Because heavy bleeding is a common symptom of fibroids, losing a lot of blood may lead to anemia. The most common anemia is a deficiency in iron. A doctor may recommend iron supplements to correct this anemia.
Cancer: Cancer is not likely to develop in women with fibroids, with a rate of less than 0.1%. However, one in every 1,000 women with fibroids can develop a form of cancer called leiomyosarcoma. Leiomyosarcoma is a rare cancer of the smooth muscle, which is found in the uterus. A fibroid may be malignant if it is growing rapidly or growing after menopause. Having fibroids does not seem to increase the risk of developing other cancers.
Infertility: Fibroids can cause infertility in some women. Fibroids may cause a distortion in the fallopian tubes or block them completely. This may also interfere with sperm passing into the fallopian tubes. Submucosal fibroids may prevent the embryo from implanting and growing by affecting the surrounding endometrial lining.
Pregnancy problems: If a woman with fibroids becomes pregnant, a number of problems may occur. There may be an increased risk of miscarriage, premature labor, abnormal fetal position, and placenta abruption (placenta separating from the uterine wall). However, studies have not confirmed these associations. Localized, benign pain during the first and second trimesters is the most common pregnancy complication. This pain could be due to fibroids growing larger, putting pressure on surrounding tissues, or pedunculated fibroids twisting around their stalks.

Treatment

General: Most women with fibroids do not have any symptoms or complications and therefore, do not need treatment. If symptoms do develop, doctors may recommend watchful waiting. A doctor and patient may consider treating fibroids depending on the symptoms, size of the fibroids, location of the fibroids, age, and whether a patient wants to get pregnant.
Medications: Most medications are given to treat the symptoms of fibroids rather than the fibroids themselves. Over-the-counter medications, such as ibuprofen (Motrin?), an anti-inflammatory, or acetaminophen (Tylenol?), may be given to help relieve pain. Birth control pills may be prescribed to help alleviate symptoms and regulate the menstrual period.
Gonadotropin releasing hormone (Gn-RH) agonists, such as leuprolide (Lupron?, Eliguard?), nafarelin (Synarel?), and goserelin (Zoladex?), may help decrease the size of fibroids. They are often given before surgery to make fibroids smaller and easier to remove. Gn-RH usually triggers a new menstrual cycle, while Gn-RH agonists do the opposite. Gn-RH agonists cause estrogen and progesterone levels to fall, which causes menstruation to stop and fibroids to shrink. Hot flashes and depression may occur because of the drop in estrogen.
Mifepristone is an anti-hormonal agent that may help stop or slow the growth of fibroids. This agent only provides temporary relief of symptoms.
Danazol is a man-made androgen, or male hormone, known to relieve fibroid symptoms. It may help decrease uterine size, stop menstruation, and reverse anemia. However, this is not commonly used among women because it can cause facial hair growth, weight gain, acne, headache, and deepening of voice.
Myomectomy: Myomectomy is a surgery that removes the fibroids but keeps the uterus in place. This may be a good option for patients who plan on having children. The size, location, and number of fibroids a person has will determine whether the surgery will be minor, performed in an outpatient setting, or major, requiring a patient to stay in the hospital for a few days. Because the uterus is left intact, fibroids may eventually grow back with this treatment. There is a 10-30% chance that fibroids will grow back. Some studies saw a 50% re-growth rate in African American women.
An abdominal myomectomy, in which the abdomen is opened up, is used in cases in which the fibroids are large and deep. A laparoscopic myomectomy, which uses a camera to locate the fibroids and a small instrument to remove the fibroids, is used for smaller fibroids and only requires small abdominal cuts. When fibroids are inside the uterus, a hysteroscopic myomectomy is conducted. The doctor places a hysteroscope through the cervix and removes the fibroids with the aid of a camera. About 20-40% of women have complications from myomectomies. Minor complications include bruising, mild infection, and fever. Bleeding and abdominal pain is expected after these procedures until a full recovery is made.
Two variations of a myomectomy, myolysis and cyromyolysis, have also been used. These procedures do not remove the fibroid but cut off the blood supply causing the fibroid to shrink and die. Myolysis uses a needle and electrical currents to destroy the vessels of the fibroids, thereby cutting off their blood supply. Cryomyolysis is similar but uses liquid nitrogen to freeze the fibroids. There is a risk of uterine rupture, so this procedure is not recommended in patients that want to get pregnant. Fibroids may not shrink with these treatments, and in some cases, cryomyolysis may cause the fibroids to increase in size. The overall safety, effectiveness, and risk of recurrence have not been determined.
Endometrial ablation: This surgery uses a hysteroscope and heat to destroy the inner lining of the uterus, known as the endometrial lining. This may help patients who have heavy bleeding, but it will not be effective for fibroids outside the uterine lining. Women are not able to have children after this procedure because the endometrial lining is needed to nourish a growing fetus.
Hysterectomy: A hysterectomy is the complete removal of the uterus and the only complete and permanent cure for fibroids. It is an invasive surgery and should only be done when the patient is not planning on having children afterwards. Removal of the ovaries is uncommon for women with fibroids, but if the ovaries are removed, menopause will be induced and a patient may have to decide if she wants hormone replacement therapy. There are many side effects after a hysterectomy, including hot flashes, weight gain, urinary incontinence, osteoporosis, and low sex drive. It is important to consider the risks and benefits of a hysterectomy.
Uterine fibroid embolization (UFE): UFE is a newer, non-surgical procedure that an interventional radiologist performs. A catheter is placed into the artery that supplies blood to the uterus and the fibroids. Tiny particles are released and the blood flow to the uterus is cut off, causing the fibroids to shrink. The procedure takes about an hour and most women stay one night in the hospital. The patient is conscious, but sedated, during the procedure and given narcotics for the pain. UFE treats all types of fibroids and is a good option for women who do not want to undergo surgery. A complication of this procedure is infection, which may affect the ovaries. Infections are typically treated with antibiotics. UFE is only suggested to those women that do not want children because the effect it has on fertility is not known. However, there have been women who have had successful pregnancies following UFE. There is some evidence suggesting that fibroids will not grow back, but more long-term data are needed.
Focused ultrasound surgery: Focused ultrasound surgery (FUS) uses a special MRI scanner to guide the doctor to the location of the fibroid. Once the fibroids are found, high-frequency, high-energy sound waves destroy the fibroids, so no incision is needed. Women who wish to avoid surgery and to preserve their uterus may benefit from this option. One treatment may last up to several hours and the long-term effects are not known.

Integrative therapies

Unclear or conflicting scientific evidence:
Traditional Chinese medicine: Chinese medicine is a broad term encompassing many different modalities and traditions of healing. These modalities share a common heritage of technique or theory rooted in ancient Chinese philosophy (Taoism) and date back more than 5,000 years. TCM practitioners may call upon a wide range of other modalities as well, from meditation and martial arts to feng shui. Human studies using TCM for fibroids have been conducted but have been of poor quality. Limited human data has shown that TCM was effective at shrinking fibroids or preventing them from growing.
There have been reports of manufactured or processed Chinese herbal products being tainted with toxins or heavy metals or not containing the listed ingredients. There have also been reports of adverse effects. Chinese herbs can interact with drugs, interfering with or exaggerating their effects. In particular, ma huang should not be taken with caffeine. Certain modalities and herbs should be avoided in pregnancy and lactation. Consumers should consult with medical professionals, including pharmacists, for recommendations on safe herbal products, dosage, and interactions with other medications.
Magnet therapy: The use of magnets to treat illness has been described historically in many civilizations and was suggested by ancient Egyptian priests and in the 4th Century BC by Hippocrates. Many different types, sizes, and strengths of magnets are available. Magnet therapy may be administered by a healthcare professional or used by individuals on their own. Constant (static) magnets or pulsed electromagnetic fields may be applied to areas of the body affected by illness or to the entire body. Early research reports reductions of pain in women with chronic refractory pelvic pain using magnet therapy. Well-designed studies are needed in this area before a conclusion can be drawn.
People with implantable medical devices, such as heart pacemakers, defibrillators, insulin pumps, or hepatic artery infusion pumps, should avoid exposure to magnets, as magnets may affect the functioning of some equipment. Some publications discourage the use of static magnets or electromagnetic field therapy during pregnancy. Some publications also suggest that magnets may cause dizziness or nausea or may prolong poor wound healing or bleeding. Scientific research is limited in these areas.
Traditional or theoretical uses lacking sufficient evidence:
Acupuncture: The practice of acupuncture originated in China 5,000 years ago. Today, acupuncture is widely used throughout the world and is one of the main pillars of traditional Chinese medicine (TCM). Acupuncture has become integrated with Western medicine as well, and it is often referred to as medical acupuncture in that context. Acupuncture has been suggested as a possible treatment for fibroids, but research is currently lacking in this area.
When performed by an experienced practitioner using standard sterile techniques, very few serious complications have been documented, despite millions of treatments conducted every year. Observational studies and randomized trials reviewing thousands of treatments have not noted any serious adverse reactions.
American pennyroyal: American pennyroyal is an herb in the mint family. Although American pennyroyal has been suggested as a possible treatment for fibroids, research is lacking in this area.
The essential oil of pennyroyal is toxic, and death has been reported after consumption of one half-ounce (15 milliliters) of the oil. Dangerous reactions may occur if pennyroyal is taken by mouth or is used on the skin. Avoid if allergic to pennyroyal or any of its components, including pulegone. Use cautiously with prescription drugs that control blood sugar levels.
Black cohosh: Black cohosh is one of the highest selling herbs in the United States and is popularly used as an alternative to hormonal therapy in the treatment of menopausal (climacteric) symptoms such as hot flashes, mood disturbances, sweating, palpitations, and vaginal dryness. Several controlled trials and case series have reported that black cohosh improved menopausal symptoms for up to six months. Although these initial studies are suggestive, they have been few in number and have universally suffered from methodological weaknesses.
Avoid if allergic to black cohosh or other members of the Ranunculaceae (buttercup or crowfoot) family. Reviews of the literature have reported black cohosh to be generally well tolerated in recommended doses for up to six months. The most common side effects seem to be gastrointestinal upset and rash. The potential effects of black cohosh on estrogen-sensitive conditions, such as breast cancer, uterine cancer, or endometriosis, are not known.
Detoxification therapy: Detoxification is a broad concept that encompasses many different modalities and substances used in cleansing the body's systems and organs. Detoxification regimes primarily target heavy metals, chemical toxins, microbial compounds, and by-products of protein metabolism. Detoxification therapy has been proposed as a treatment for fibroids. However, human studies are currently lacking.
Side effects and warnings depend on the specific therapy used. During some detoxification processes, toxins may be released from tissues and then build up in the bloodstream en route to being excreted, temporarily causing a worsening of symptoms before they are completely excreted. This is called the Herxheimer reaction and it is most often associated with die-off of toxin-producing organisms, such as yeasts, fungi, parasites, and bacteria, but it may theoretically occur with the release of other kinds of toxins.

Prevention

Current research is focused on the cause of fibroids. Currently there is limited data available on how a woman can prevent fibroids.
Weight control and diet may help to decrease the risk of fibroids. A diet that limits red meat and is rich in green, leafy vegetables, fruit, and fish may be beneficial. These are theoretical preventive measures because the exact cause of fibroids has not been reported in the available literature.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

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Causes

General: The cause of fibroids remains unknown. There are some theories, but researchers are continuing to study what exactly causes the growth. The cause may be genetic, hormonal, environmental, or a combination of all of these factors.
Genetics: A specific gene causing fibroids has not been identified. However, if a person has a grandmother, mother, or sister who suffers from fibroids, she is twice as likely to develop them.
Hormones: Researchers have observed that fibroids grow during pregnancy because there is an abundance of estrogen and progesterone, and shrink after menopause, when there are very low levels of estrogen and progesterone. Although hormones may contribute to the growth of fibroids, their exact role is not known.
Growth factors: Growth factors are proteins that regulate a process known as angiogenesis, which is the growth of new blood vessels from pre-existing ones. The new blood vessels then allow blood to flow to any existing growth, including fibroids. Growth factors may play a role in fibroid development.

Risk factors

General: There is ongoing research to find the cause of and risk factors for fibroids. Women of childbearing age are most likely to develop fibroids, but symptoms usually do not appear until a woman is between 35 and 50 years old. Even though fibroids tend to run in families, it is unclear if the condition is hereditary because no genetic patterns have been observed. A few risk factors have been identified.
Diet: According to recent research, eating red meat, such as beef and ham, is associated with the presence of fibroids. Eating green vegetables, fruit, and fish, on the other hand, is associated with a reduced risk for fibroids.
Hormone levels: Hormone levels may have an impact on the development of uterine fibroids. It is believed that estrogen and progesterone, two female hormones, may cause an increase in fibroid growth. When a woman is pregnant, fibroids grow more rapidly because of increased hormone levels, and the fibroids shrink after menopause because of decreased hormone levels.
Obesity: Women who are overweight or obese also tend to have a slightly higher risk for fibroid growth.
Ethnicity: African American women have an increased risk of developing fibroids, and they are 2-3 times more likely to develop symptomatic fibroids. They are also more likely to experience symptoms at an earlier age than other women, which could be due to the fact they usually have larger and more numerous fibroids. Asian women are least likely to have uterine fibroids, according to recent research.

Types of the disease

General: Fibroids are classified by where they grow in relation to the uterus. There are subserosal fibroids (outside the uterus), intramural fibroids (in the middle of the uterus), and submucosal fibroids (inside of the uterus, near the endometrial lining). Peduncles are stalks that can grow on the surface of the uterus, and they can develop fibroids themselves known as pedunculated fibroids. Pedunculated fibroids are sometimes a subclassification of subserosal or submucosal fibroids, but some doctors classify them as in their own group. A woman can have one type of fibroid, a couple of types, or all the types of fibroids.
Subserosal fibroids: These fibroids grow on the outside of the uterus and, as they grow, they expand further out into the uterine cavity. Subserosal fibroids generally have no effect on menstrual flow, but they may cause lower back pain, pelvic pain, increased urination, and constipation if they push onto the surrounding tissues/organs. Subserosal fibroids account for about 20% of all fibroid cases.
Intramural fibroids: In this type, the fibroids grow from within the uterine wall and they expand inward, causing the uterus to bulge. A doctor may suspect intramural fibroids if the uterus feels larger than normal during an examination. Intramural fibroids are the most common, accounting for about 70% of all fibroid cases, and they can potentially cause any of the symptoms associated with fibroids.
Submucosal fibroids: Fibroids that grow just under the inner lining of the uterine cavity (called the endometrial lining) are called submucosal fibroids. They are the least common type of fibroid, accounting for only 5% of all cases. But even a small submucosal fibroid may cause symptoms of heavy bleeding and prolonged menstrual periods.
Pedunculated fibroids: Peduncles are stalk-like growths on the inside or the outside of the uterus where a fibroid can grow and hang off. When a fibroid grows on a peduncle, it is called a pedunculated fibroid. If the fibroid is growing on the inside of the uterus, it is considered a pendunculated submucosal fibroid. If it is growing on the outside of the uterus, it is a pendunculated subserosal fibroid. The stalks on pedunculated fibroids have the ability to twist, which may cause severe or chronic pain or pressure on surrounding tissues.