Residency · Residency · Obstetrics Gynecology

Uterine Fibroids: Medical and Surgical Management

Overview

Uterine fibroids (leiomyomas) are benign monoclonal neoplasms arising from myometrial smooth muscle. They are the most common pelvic tumor in women, with a prevalence of 70 to 80% by age 50 and symptoms in 25 to 50%. Black women have a 2- to 3-fold higher risk, with earlier onset and often more severe disease. Fibroids are estrogen- and progesterone-dependent, growing during the reproductive years and regressing after menopause.

Classification (FIGO Subclassification)

The FIGO system classifies fibroids by their relationship to the endometrial cavity and uterine serosa. Type 0 is a pedunculated intracavitary fibroid entirely within the cavity. Type 1 is submucosal with less than 50% intramural extension. Type 2 is submucosal with 50% or more intramural extension. Type 3 contacts the endometrium but is 100% intramural. Type 4 is entirely intramural with no endometrial or serosal involvement. Type 5 is subserosal with 50% or more intramural extension. Type 6 is subserosal with less than 50% intramural extension. Type 7 is a pedunculated subserosal fibroid. Type 8 encompasses other locations including cervical, parasitic, and broad ligament fibroids. Submucosal fibroids (types 0 through 2) are the most likely to cause abnormal uterine bleeding and affect fertility.

Clinical Presentation

Symptoms

Heavy menstrual bleeding is the most common symptom, presenting as prolonged, heavy periods often leading to iron-deficiency anemia. Bulk symptoms include pelvic pressure, urinary frequency or retention (from anterior fibroids compressing the bladder), constipation (from posterior fibroids), and rarely hydronephrosis. Pain may manifest as dysmenorrhea, dyspareunia, or acute pain with torsion of a pedunculated fibroid or red degeneration in pregnancy. Reproductive effects include infertility (particularly with submucosal and large intramural fibroids), recurrent pregnancy loss, preterm labor, and malpresentation. Many fibroids are asymptomatic and found incidentally.

Degeneration Patterns

Hyaline degeneration is the most common. Red (carneous) degeneration occurs during pregnancy and presents with acute pain and low-grade fever, managed conservatively with analgesics. Cystic degeneration and calcification (typically postmenopausal) also occur. Sarcomatous degeneration is extremely rare at less than 0.5%, and most uterine sarcomas arise de novo rather than from pre-existing fibroids.

<image>FIGO fibroid subclassification diagram showing a uterine cross-section with fibroids of each type labeled: Type 0 pedunculated intracavitary, Type 1 and 2 submucosal, Types 3-4 intramural, Types 5-6 subserosal, Type 7 pedunculated subserosal, and Type 8 cervical, with the endometrial cavity and serosal surface clearly delineated</image>

Evaluation

Physical exam reveals an enlarged, irregular, firm uterus. Transvaginal ultrasound is the first-line imaging study and identifies the number, size, and location of fibroids. Saline infusion sonohysterography delineates the intracavitary component of submucosal fibroids. MRI provides the most precise mapping before myomectomy, distinguishes fibroids from adenomyosis, and can evaluate for sarcoma (suggested by rapid growth, irregular borders, and high signal on diffusion-weighted imaging). Endometrial biopsy is indicated for abnormal uterine bleeding evaluation per age-based guidelines to rule out endometrial pathology. CBC and ferritin assess for iron-deficiency anemia.

Medical Management

Hormonal Therapies

The levonorgestrel IUD (Mirena or Liletta) reduces menstrual blood loss by 70 to 90%. It does not shrink fibroids but effectively treats the associated bleeding. It may be expelled if a large submucosal fibroid distorts the cavity. It is an excellent option for women with fibroids smaller than 5 cm without significant cavity distortion.

Combined hormonal contraceptives reduce menstrual blood loss but do not significantly shrink fibroids and may not be effective for large fibroids.

GnRH agonists such as leuprolide depot create a hypoestrogenic state that shrinks fibroids by 35 to 60% over 3 to 6 months. They are used preoperatively to reduce fibroid size, correct anemia, and facilitate surgery. Side effects include hot flashes, bone loss, and vaginal dryness. They cannot be used long-term without add-back therapy (norethindrone 5 mg daily), and fibroids regrow after discontinuation.

Oral GnRH antagonist combinations represent a major advance in medical management. Elagolix with add-back (Oriahnn) combines elagolix 300 mg twice daily with estradiol 1 mg and norethindrone acetate 0.5 mg daily as integrated add-back. The relugolix combination tablet (Myfembree) combines relugolix 40 mg with estradiol 1 mg and norethindrone 0.5 mg daily. These agents reduce heavy menstrual bleeding by 50 to 70%, can be used long-term (studied for up to 2 years), and maintain bone density with add-back therapy. They are the first effective long-term oral medical therapies for fibroids.

Non-Hormonal Therapies

Tranexamic acid at 1,300 mg three times daily during menses reduces blood loss by approximately 40%. NSAIDs provide modest reduction in menstrual blood loss. Iron supplementation, either oral or intravenous (ferric carboxymaltose, iron sucrose), addresses iron-deficiency anemia.

Surgical Management

Myomectomy

Myomectomy removes fibroids while preserving the uterus and is preferred for women desiring future fertility. Hysteroscopic myomectomy is performed for submucosal fibroids (types 0, 1, and 2). It is an outpatient procedure with no abdominal incision, using a resectoscope or morcellator to remove fibroid tissue. Type 0 fibroids are usually completed in one procedure, while type 2 fibroids may require staged procedures for large intramural components. Fluid deficit must be monitored closely because of the risk of hyponatremia with hypotonic distension media.

Laparoscopic or robotic myomectomy is used for subserosal and intramural fibroids. It offers less blood loss, shorter recovery, and fewer adhesions compared with open surgery. It requires morcellation for specimen removal. There may be a higher uterine rupture risk in subsequent pregnancy if the cavity was entered, though this remains controversial.

Abdominal myomectomy via laparotomy is appropriate for very large or numerous fibroids. It provides the best visualization and access for multiple deep intramural fibroids but involves higher blood loss and longer recovery. Multilayer myometrial closure is performed for future pregnancy safety.

After myomectomy, cesarean delivery is recommended if the myometrium was deeply incised, especially if the cavity was entered. A waiting period of 3 to 6 months before conceiving is advised. The uterine rupture risk is approximately 0.5 to 1%, with some series reporting higher rates after laparoscopic approaches.

Uterine Artery Embolization (UAE)

UAE is an interventional radiology procedure involving bilateral uterine artery catheterization and embolization with polyvinyl alcohol particles or microspheres. It causes fibroid ischemia and necrosis, with an average 40 to 60% volume reduction. It is effective for heavy menstrual bleeding (80 to 90% improvement) and bulk symptoms. It is not recommended for women desiring future fertility because of insufficient safety data and the risk of ovarian compromise. Complications include post-embolization syndrome (pain, fever, and nausea lasting 7 to 10 days), fibroid expulsion, amenorrhea (with risk increasing with age), and rarely infection.

MRI-Guided Focused Ultrasound (MRgFUS/HIFU)

This non-invasive technique uses focused ultrasound waves guided by MRI for thermal ablation of fibroids. It reduces fibroid volume by 20 to 40%. It is limited to fibroids with specific characteristics (accessible, not too large). Long-term data are limited, and retreatment may be needed. Fertility data are also limited.

Hysterectomy

Hysterectomy is the definitive treatment for symptomatic fibroids when fertility is not desired. It can be performed vaginally, laparoscopically, robotically, or via laparotomy, with the route depending on uterine size, surgical history, and surgeon expertise. It eliminates the possibility of fibroid recurrence. Concurrent bilateral salpingectomy should be considered for ovarian cancer risk reduction. Ovarian conservation is recommended in premenopausal women without ovarian pathology.

Power Morcellation Controversy

Power morcellation uses an electromechanical device to divide tissue for removal through small laparoscopic incisions. The concern is the risk of spreading undiagnosed leiomyosarcoma, with incidence estimates of approximately 1 in 340 to 500 hysterectomies. The FDA issued a boxed warning in 2014 against the use of power morcellation for most women with fibroids. Contained morcellation using a containment bag to prevent tissue dissemination has some supporting data. Mini-laparotomy for specimen extraction without morcellation is an alternative.

<image>Comparison of surgical and interventional approaches to uterine fibroids: hysteroscopic myomectomy for submucosal fibroids showing resectoscope in the uterine cavity, laparoscopic myomectomy with port placement and specimen in containment bag, uterine artery embolization showing catheter placement and embolized vessels, and total hysterectomy specimen</image>

Fibroids and Fertility

Submucosal fibroids significantly impair fertility and should be removed via hysteroscopic myomectomy. Intramural fibroids larger than 4 to 5 cm, especially those distorting the cavity, may reduce IVF success. Subserosal fibroids generally do not affect fertility. Myomectomy before IVF should be considered for submucosal and large cavity-distorting intramural fibroids. The recurrence rate after myomectomy is 15 to 30% at 5 years.

Clinical Pearls

Submucosal fibroids are the most clinically significant for abnormal uterine bleeding and infertility. Always assess the intracavitary component with SIS or hysteroscopy.

The levonorgestrel IUD is the most effective medical treatment for fibroid-related heavy menstrual bleeding but does not shrink fibroids.

Oral GnRH antagonist combinations (relugolix and elagolix with add-back) represent a paradigm shift as the first effective long-term oral medical therapies for fibroids.

Rapid fibroid growth is not a reliable indicator of sarcoma. Most rapidly growing fibroids are benign. However, new growth in a postmenopausal woman warrants further evaluation.

UAE is not recommended for women desiring future fertility. Myomectomy is preferred.

When morcellation is needed, use a containment bag to minimize the risk of tissue dissemination.

Black women have higher fibroid prevalence, earlier onset, and more severe symptoms. Be proactive in screening and treatment for this population.

References

• ACOG Practice Bulletin No. 228: Management of Symptomatic Uterine Leiomyomas (2021)
• ACOG Committee Opinion No. 822: Uterine Morcellation for Presumed Leiomyomas (2021)
• Stewart EA. Uterine fibroids. N Engl J Med. 2015;372:1646-1655
• Al-Hendy A et al. Relugolix combination therapy for fibroid-associated HMB (LIBERTY 1 and 2). N Engl J Med. 2021;384:630-642
• Gupta JK et al. Uterine artery embolization for symptomatic uterine fibroids. Cochrane Database Syst Rev. 2014
• Pritts EA et al. Fibroids and infertility: an updated systematic review of the evidence. Fertil Steril. 2009;91:1215-1223

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