Uterine leiomyoma

Last updated: October 12, 2021

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Uterine leiomyomas (fibroids) are benign, hormone-sensitive uterine neoplasms. These tumors are classified as either submucosal (beneath the endometrium), intramural (within the muscular uterine wall of the uterus), or subserosal (beneath the peritoneum). Symptoms depend on the location, size, and number of myomas, and include menstrual abnormalities (menorrhagia), features of mass effects (e.g., back/abdominal/pelvic pain or bladder and bowel dysfunction), and infertility. Physical examination and sonohysterography are used to establish the diagnosis. Treatment for symptomatic patients includes surgery (myomectomy or hysterectomy) as well as interventional (uterine artery embolization) and/or medical therapy (GnRH agonists).

Predisposing factors


Leiomyomas are classified according to their location. [3]

  • Subserosal leiomyoma: located in the outer uterine wall beneath the peritoneal surface
  • Intramural leiomyoma (most common): growing from within the myometrium wall
  • Submucosal leiomyoma: located directly below the endometrial layer (uterine mucosa)
  • Cervical leiomyoma: located in the cervix
  • Diffuse uterine leiomyomatosis: The uterus is grossly enlarged due to the presence of numerous fibroids.

Most women have small, asymptomatic fibroids. Symptoms depend on the number, size, and location of leiomyomas.


  • Macroscopic
    • Grayish-white surface
    • Homogeneous; tissue bundles on cross-section partly in a whorled pattern
    • Some leiomyomas may involve regressive changes: scar formation, calcification, and cysts
  • Microscopic: Smooth muscle tissue in a whorled pattern with well-demarcated borders, consisting of monoclonal cells interspersed with connective tissue


Differential diagnosis of uterine leiomyoma
Factors Uterine leiomyoma (fibroids) Adenomyosis Endometriosis Uterine polyps Uterine leiomyosarcoma [6][7]
  • Overgrowth of localized endometrial tissue attached to the inner wall of the uterus, usually benign [8]
Risk factors
Clinical features
  • Symptoms similar to uterine fibroids
  • Menstrual irregularities
  • Postmenopausal bleeding
  • Pelvic pain
Uterine findings
  • Irregularly enlarged, firm
  • Uniformly enlarged
  • Typically not enlarged
  • Typically not enlarged
  • Rapidly enlarging

The differential diagnoses listed here are not exhaustive.

Treatment should only be considered in symptomatic patients because of the side effects of medical therapy and surgery. The goal is to relieve symptoms. Perimenopausal women warrant expectant management in most cases.

Asymptomatic fibroids

  • Do not require treatment
  • Frequent follow-ups (approx. every 6–12 months) with pelvic ultrasonography and symptom monitoring
  • Patients should be counseled to contact their physician if new symptoms develop.

Symptomatic fibroids

The choice of treatment modality depends on the patient's desire to preserve fertility, other personal preference, comorbidities (e.g., contraindications to surgery), and severity of symptoms.

Postmenopausal patients and those who do not wish to conceive in the future are eligible for all forms of treatment, i.e., medical therapy, interventional therapy, and surgery. The options available to patients who wish to conceive in the future are medical therapy and myomectomy.

Treatment options that preserve fertility

Treatment options that will affect fertility

  • Interventional therapy
    • Uterine artery embolization: a percutaneous, radiologic procedure in which an embolic agent is injected into the uterine artery in order to block the blood supply to the fibroid(s)
      • Procedure
        • Injection of polyvinyl alcohol (PVA) into the arteries that supply the fibroid, causing it to shrink
        • 25% of patients require further invasive treatment (e.g., hysterectomy) due to failed embolization or recurrent symptoms
      • Indications
        • Recurrent refractory heavy bleeding and/or severe pain unresponsive to medical treatment
        • Contraindications to surgery or personal preference to avoid surgery
        • No desire to preserve fertility, but wish to preserve the uterus
    • Magnetic resonance-guided focused ultrasound surgery (MRgFUS): a procedure that utilizes MRI and ultrasound waves to destroy fibroids
  • Surgery: hysterectomy with/without bilateral salpingo-oophorectomy (definitive treatment) )

We list the most important complications. The selection is not exhaustive.

Uterine leiomyomas during pregnancy


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  4. Uterine leiomyoma. https://radiopaedia.org/articles/uterine-leiomyoma. Updated: February 17, 2017. Accessed: February 17, 2017.
  5. Uterus Stromal tumors Leiomyoma. http://www.pathologyoutlines.com/topic/uterusleiomyoma.html. Updated: February 9, 2017. Accessed: March 14, 2017.
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  8. Wethington SL, Herzog TJ, Burke WM, et al. Risk and Predictors of Malignancy in Women with Endometrial Polyps. Ann Surg Oncol. 2011; 18 (13): p.3819-3823. doi: 10.1245/s10434-011-1815-z . | Open in Read by QxMD
  9. Stewart E. Uterine adenomyosis. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/uterine-adenomyosis?source=search_result&search=adenomyosis&selectedTitle=1~51#H6.Last updated: February 9, 2017. Accessed: February 17, 2017.
  10. Oliva E. Practical issues in uterine pathology from banal to bewildering: the remarkable spectrum of smooth muscle neoplasia. Modern Pathology. 2015; 29 (S1): p.S104-S120. doi: 10.1038/modpathol.2015.139 . | Open in Read by QxMD
  11. Ouyang DW, Norwitz ER. Pregnancy in Women with Uterine Leiomyomas (Fibroids). In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/pregnancy-in-women-with-uterine-leiomyomas-fibroids.Last updated: December 19, 2017. Accessed: February 21, 2018.
  12. Bharambe BM, Deshpande KA, Surase SG, Ajmera AP. Malignant transformation of leiomyoma of uterus to leiomyosarcoma with metastasis to ovary. J Obstet Gynaecol India. 2012; 64 (1): p.68-69. doi: 10.1007/s13224-012-0202-4 . | Open in Read by QxMD

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