Uterine Fibroids

Uterine fibroids (leiomyomas) are benign smooth muscle tumors of the myometrium, the most common pelvic tumor in women, with prevalence increasing with age through the reproductive years and higher prevalence and earlier onset in women of African descent.

Classified by location: submucosal (projecting into the endometrial cavity, most strongly associated with heavy bleeding and subfertility), intramural (within the myometrium, the most common location), and subserosal (projecting outward from the uterine surface, more likely to cause bulk symptoms than bleeding).

Growth is estrogen and progesterone dependent, and fibroids typically regress after menopause.

Many fibroids are asymptomatic and identified incidentally.

Symptomatic disease presents with heavy menstrual bleeding (particularly with submucosal or larger intramural fibroids), bulk symptoms (abdominal or pelvic pressure, urinary frequency from bladder compression, constipation from rectal compression), and, less commonly, subfertility or recurrent miscarriage (particularly with submucosal fibroids distorting the endometrial cavity).

Acute severe pain can occur with fibroid degeneration (particularly "red degeneration" in pregnancy, from outgrowing its blood supply) or, rarely, torsion of a pedunculated subserosal fibroid.

Transvaginal ultrasound is first line, characterizing number, size, and location.

MRI provides more detailed mapping where surgical or interventional treatment is being planned, particularly for multiple or large fibroids, or where adenomyosis needs to be distinguished from fibroid disease.

Hysteroscopy allows direct visualization and, where appropriate, simultaneous resection of submucosal fibroids.

FBC to assess for anemia given the frequent association with heavy bleeding.

Management depends on symptom severity, fibroid size and location, and fertility desires.

• Asymptomatic fibroids: no treatment required, monitoring only
• Medical management of bleeding symptoms: as per the Menorrhagia and Abnormal Uterine Bleeding entries, tranexamic acid, NSAIDs, the levonorgestrel-releasing IUD (though less effective and higher expulsion risk with significant cavity distortion from submucosal fibroids), and combined oral contraceptive
• GnRH agonists (e.g. goserelin) or, increasingly, oral GnRH antagonist combinations (e.g. relugolix combined with estradiol and norethisterone, where available) provide effective medical shrinkage and symptom control, generally used short term (up to 6 months for standalone GnRH agonists without add-back) as a bridge to surgery or to manage perimenopausal symptoms until natural menopause
• Ulipristal acetate, previously widely used for fibroid-related bleeding and pre-surgical shrinkage, has had its use significantly restricted or withdrawn in several regulatory jurisdictions due to rare but serious hepatotoxicity, check current local guidance before use
• Uterine artery embolization: an interventional radiology procedure occluding the fibroid blood supply, effective for bleeding and bulk symptoms, uterus-preserving, though generally not recommended for women prioritizing future fertility given some evidence of reduced ovarian reserve and less certain impact on pregnancy outcomes compared with myomectomy
• Myomectomy (hysteroscopic for submucosal fibroids, or laparoscopic/open for intramural or subserosal fibroids): fertility-preserving surgical option, with a recognized risk of fibroid recurrence over time
• Hysterectomy: definitive treatment for women who have completed childbearing and have significant symptoms refractory to other measures, or very large or numerous fibroids
• Fibroids in pregnancy: most remain asymptomatic; red degeneration presents with acute, localized pain and is managed conservatively with analgesia (paracetamol and, if needed, opioids, avoiding NSAIDs particularly in the third trimester); fibroids can contribute to malpresentation, obstructed labor, or postpartum hemorrhage depending on size and location, requiring individualized delivery planning

Referral: gynecology for symptomatic fibroids requiring intervention; interventional radiology for uterine artery embolization; fertility services where subfertility is attributed to fibroid disease.