Obstetrics and Gynecology· Topic 11.3 Uterine and cervical disorders· 11.3.1

Uterine fibroids

Uterine leiomyomas are benign monoclonal smooth-muscle tumors of the myometrium that cause heavy menstrual bleeding, bulk symptoms, and reproductive dysfunction; management ranges from expectant care to hormonal bleeding control to fertility-sparing or definitive surgery.

13 min read9 practice questions8 key factsSubscriber article
  • Topic review
    The full article, organized the way the exam asks it.
  • ABIM-format MCQs
    Vignettes with an explanation for every wrong answer.
  • Key facts
    The numbers and thresholds worth memorizing, up front.
  • AI tutor
    MedBrain answers the question you're stuck on.

What this article covers

  • Overview

    Benign monoclonal smooth-muscle tumor: uterine leiomyomas (fibroids or myomas) arise from myometrial smooth muscle and are the most common benign neoplasm of the female genital tract, presenting as…

  • Epidemiology

    Very common, age-related: fibroids occur in 50% to 80% of women, most prevalent during the reproductive years, typically regressing after menopause.

  • Risk factors

    Reproductive age: the peak incidence window; risk falls sharply after menopause.

  • Pathophysiology

    Monoclonal smooth-muscle proliferation: each fibroid arises from a single myometrial smooth-muscle cell with a somatic mutation, proliferating clonally, so one uterus can carry multiple genetically distinct tumors.

  • Clinical features

    Majority asymptomatic: most fibroids are incidental findings on exam or imaging for another reason.

  • Differential diagnosis

    Adenomyosis: cyclic but heavy, prolonged menses with severe cramping and dyspareunia; uterus is uniformly, symmetrically enlarged, globular, and boggy rather than irregular and nodular, with…

  • Diagnosis

    Confirmatory basis, exam first then confirmed by imaging: an enlarged, irregular, firm, nontender uterus on bimanual exam suggests fibroids; the diagnosis is confirmed by transvaginal ultrasound…

  • Management

    First, if fibroids are asymptomatic, treat with expectant observation only: annual pelvic examination and CBC as clinically indicated; routine surveillance imaging is not required.

  • Complications

    Iron deficiency anemia: the most common clinically significant complication, from chronic heavy blood loss; confirm with CBC and iron studies and treat with oral iron replacement as above.

  • Prognosis

    Favorable overall course: most fibroids remain asymptomatic or minimally symptomatic and regress after menopause; most women require no intervention.

  • Prevention

    No proven primary prevention: no screening test or intervention prevents fibroid formation; efforts focus on early symptom recognition and modifiable risk-factor reduction.

Read the whole article

Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.