Fibroid Uterus
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Direct answer
Uterine leiomyomas (fibroids) are benign monoclonal smooth-muscle tumours — the commonest benign tumours of the uterus — that grow under oestrogen influence and shrink after menopause. Many are silent, but they commonly present with heavy or prolonged menstrual bleeding, pressure symptoms, or infertility and recurrent miscarriage when a submucous fibroid distorts the cavity. Treatment spans observation, medical suppression, myomectomy and hysterectomy.
What you must remember
- Types by position — intramural (commonest), submucous (most symptomatic, causing abnormal bleeding, infertility and miscarriage), subserosal (which may be pedunculated) and cervical.
- In the PALM-COEIN classification of abnormal uterine bleeding, fibroids form the L of the structural causes — polyp, adenomyosis, leiomyoma, malignancy.
- Degenerations — hyaline (commonest), cystic, fatty, calcific in older women, red or carneous in pregnancy (acute painful infarction), and rarely sarcomatous change.
- Fibroids are enclosed in a pseudocapsule of compressed myometrium, which allows enucleation at myomectomy; torsion of a pedunculated subserosal fibroid causes acute abdomen.
- Diagnosis — transvaginal ultrasound is first line; saline infusion sonography and hysteroscopy assess submucous lesions; MRI best maps multiple or complex fibroids before surgery.
- Management — asymptomatic fibroids are observed; medical options include tranexamic acid, the levonorgestrel intrauterine system for cycle control, and GnRH agonists which shrink fibroids for about three to six months (used pre-operatively, with hypo-oestrogenic side effects and regrowth on stopping).
- Surgery — hysteroscopic resection for submucous fibroids, myomectomy to preserve fertility, and hysterectomy as the definitive treatment when the family is complete; uterine artery embolisation suits selected women. Rapid enlargement after menopause should raise suspicion of rare sarcomatous change.
Common confusion
Fibroids and adenomyosis present with similar heavy bleeding and are frequently interchanged. Fibroids are discrete, capsulated masses that enlarge the uterus asymmetrically and are palpable as knobbed enlargement; adenomyosis is a diffuse, globular, often tender uterus with dysmenorrhoea and myometrial cysticity on ultrasound. Red degeneration in pregnancy is another trap — it presents with acute pain, tenderness and low-grade fever, mimicking torsion or appendicitis, and is managed conservatively.
Exam-focused takeaway
Type-versus-symptom matching is the standard stem — submucous with bleeding and infertility, subserosal with pressure or a palpable mass. Degeneration one-liners (hyaline commonest, red in pregnancy, calcific postmenopausal) recur, as does the PALM-COEIN "L" and the choice between myomectomy and hysterectomy based on fertility wishes.
Frequently asked questions
Which fibroids cause the most symptoms?
Submucous fibroids, because they distort the endometrial cavity — producing heavy or prolonged menstrual bleeding, infertility and pregnancy loss, often even when small.
What is red degeneration?
Acute ischaemic infarction of a fibroid, typically in pregnancy, causing sudden pain, tenderness and mild fever. It is managed conservatively with analgesia, and usually settles.
How are fibroids investigated?
Transvaginal ultrasound is the first-line imaging test. Hysteroscopy or saline infusion sonography evaluates submucous fibroids, and MRI maps complex or multiple fibroids before surgery.
When is myomectomy preferred over hysterectomy?
When the woman desires fertility or wishes to retain the uterus — understanding that fibroids can recur. Hysterectomy is definitive for women with severe symptoms who have completed their family.
Do fibroids turn cancerous?
Malignant transformation into leiomyosarcoma is rare. Rapid growth, postmenopausal enlargement or bleeding warrants careful evaluation to exclude it.