Uterine fibroids are benign uterine tumors of smooth muscle origin. Fibroids frequently cause abnormal vaginal bleeding (eg, menorrhagia, menometrorrhagia), pelvic pain and pressure, urinary and intestinal symptoms, and pregnancy complications. Diagnosis is by pelvic examination and ultrasonography. Treatment of symptomatic patients depends on the patient's desire for fertility and desire to keep her uterus and may include oral contraceptives, brief presurgical gonadotropin-releasing hormone therapy to shrink fibroids, and more definitive surgical procedures (eg, hysterectomy, myomectomy, endometrial ablation).
Uterine fibroids are the most common pelvic tumor, occurring in about 70% of women by age 45. However, many fibroids are small and asymptomatic. About 25% of white and 50% of black women have symptomatic fibroids. Fibroids are more common among women who have a high body mass index. Potentially protective factors include parturition and cigarette smoking.
Most fibroids in the uterus are subserous, followed by intramural, then submucosal. Occasionally, fibroids occur in the broad ligaments (intraligamentous), fallopian tubes, or cervix. Some fibroids are pedunculated. Most fibroids are multiple and develop from a single monoclonal smooth muscle cell. Because they have estrogen receptors, fibroids tend to enlarge during the reproductive years and regress after menopause.
Large fibroids may outgrow their blood supply and degenerate. Degeneration is described as hyaline, myxomatous, calcific, cystic, fatty, red (usually only during pregnancy), or necrotic. Although patients are often concerned about cancer in fibroids, sarcomatous change is extremely rare.
Symptoms and Signs
Fibroids can cause menorrhagia or menometrorrhagia. If fibroids grow, degenerate, or hemorrhage or if pedunculated fibroids twist, severe acute or chronic pressure or pain can result. Urinary symptoms (eg, urinary frequency or urgency) can result from bladder compression, and intestinal symptoms (eg, constipation) can result from intestinal compression.
Fibroids may prevent pregnancy; during pregnancy, they may cause recurrent spontaneous abortion, premature contractions, or abnormal presentation or make cesarean delivery necessary.
The diagnosis is likely if bimanual pelvic examination detects an enlarged, mobile, irregular uterus that is palpable above the pelvic symphysis. Confirmation requires imaging, usually with ultrasonography or sonohysterography. In sonohysterography, saline is instilled into the uterus, enabling the sonographer to more specifically locate the fibroid in the uterus. If ultrasonography is inconclusive, MRI, the most accurate imaging test, is done.
Asymptomatic fibroids do not require treatment. Patients are reevaluated periodically (eg, every 6 to 12 mo).
For symptomatic fibroids, medical options, including suppression of ovarian hormones to stop the bleeding, are suboptimal and limited. However, menorrhagia or menometrorrhagia should be treated before surgery is considered. GnRH analogs are commonly given before surgery to shrink fibroid tissues, often stopping menses and allowing blood counts to increase. In postmenopausal women, expectant management can be tried because symptoms may resolve as fibroids regress.
Several drugs are used to relieve symptoms, reduce fibroid growth, or both.
GnRH analogs given IM or sc (eg, leuprolide 3.75 mg IM q mo, goserelin 3.6 mg sc q 28 days), as a subdermal pellet, or as nasal spray can decrease estrogen production. These drugs are most commonly used. GnRH analogs are most helpful when given preoperatively to reduce fibroid and uterine volume, making surgery technically more feasible and reducing blood loss. In general, these drugs should not be used in the long term because rebound growth to pretreatment size within 6 mo is common and bone demineralization may occur.
Exogenous progestins can partially suppress estrogen stimulation of uterine fibroid growth. Medroxyprogesterone acetate 5 to 10 mg po once/day or megestrol acetate 10 to 20 mg po once/day given 10 to 14 days each menstrual cycle can limit heavy bleeding, beginning after 1 or 2 treatment cycles. Alternatively, oral therapy every day of the month (continuous therapy) may be given; it often reduces bleeding and provides contraception. Depot medroxyprogesterone acetate 150 mg IM q 3 mo has effects similar to those of continuous oral therapy. Before IM therapy, oral progestins should be tried to determine whether patients can tolerate the adverse effects (eg, weight gain, depression, irregular bleeding). Progestin therapy causes fibroids to grow in some women.
Antiprogestins (eg, mifepristone) can also help reduce fibroid growth. The dose is 5 to 50 mg (once/day for 3 to 6 mo), which is lower than the 200-mg dose used for termination of pregnancy; thus, it must be mixed specially by the pharmacy and may not always be available.
Selective estrogen receptor modulators (SERMs; eg, raloxifene) may help reduce fibroid growth. However, whether efficacy in reducing symptoms is comparable to that of other drugs is unclear.
Danazol, an androgenic agonist, can suppress fibroid growth but has a high rate of adverse effects (eg, weight gain, acne, hirsutism, edema, hair loss, deepening of the voice, flushing, sweating, vaginal dryness) and is thus often less acceptable to patients.
NSAIDs can be used to treat pain but probably do not decrease bleeding.
Surgery is usually reserved for women with any of the following:
Hysterectomy or myomectomy is traditionally done; both are major surgery and have similar indications. Hysterectomy is the definitive treatment. After myomectomy, new fibroids may begin another growth phase, and about 25% of women who have a myomectomy have a hysterectomy about 4 to 8 yr later. However, if women desire pregnancy or want to keep their uterus, myomectomy is used. In about 55% of women with infertility due to fibroids alone, myomectomy can restore fertility, resulting in pregnancy after about 15 mo. Multiple myomectomy can be much more difficult to do than hysterectomy. Patient choice is important but must be based on full information about anticipated difficulties and sequelae of myomectomy vs hysterectomy.
Newer procedures may relieve symptoms, but duration of symptom relief and efficacy of the procedures in restoring fertility have not been evaluated. Such procedures include laparoscopic and hysteroscopic myomectomy (using an instrument with a wide-angle telescope and electrical wire loop for excision), high-intensity focused sonography, cryotherapy, and radiofrequency ablation. Complication rates after laparoscopic myomectomy may be higher, but rates appear to be operator-dependent. Uterine artery embolization has been used with the aim of causing infarction of fibroids throughout the uterus while preserving normal uterine tissue. After this procedure, women recover more quickly than after hysterectomy or myomectomy, but rates of complications and return visits tend to be higher.
Choice of treatment:
Treatment should be individualized, but some factors can help with the decision:
Last full review/revision December 2008 by Bryan D. Cowan, MD
Content last modified February 2012