Uterine Fibroids

Common benign smooth muscle tumours originating in uterine myometrial cells. Affect 40–80% of women by age 50. Most common indication for hysterectomy, as symptoms can be very debilitating.

Malignancy risk

All uterine masses must be assessed for malignancy, particularly in the postmenopausal group — 1–2 in 1000 uterine masses are malignant. Suspicious features: rapid growth, particularly postmenopausal and not on HRT; tamoxifen use within 5 years carries a 3× higher risk of leiomyosarcoma. Preoperative differentiation between benign fibroids and uterine malignancy is difficult but important, since most women want to preserve their uterus — laparoscopic biopsy/resection is becoming more common.

Differential diagnosis:

• Uterine — pregnancy, haematoma, leiomyosarcoma.
• Extra-uterine — ovarian cyst, ovarian malignancy, ectopic pregnancy, pyosalpinx, hydrosalpinx, primary fallopian tube neoplasm, pelvic abscess, colorectal carcinoma, bladder carcinoma.

History and examination

Ask the same questions as for dysmenorrhoea/heavy menstrual bleeding — often presents with abnormal uterine bleeding (menorrhagia/dysmenorrhoea) and symptoms of anaemia/iron deficiency. Pressure symptoms: urinary frequency, retention, tenesmus. History of subfertility. Acute pelvic pain can occur when a fibroid outgrows its blood supply and degenerates/becomes necrotic.

Examination: abdominal and pelvic exam may reveal a firm, palpable uterine mass — larger fibroids distend the abdomen.

Investigations

No specific blood test diagnoses fibroids, but baseline bloods help differentiate: FBC, U&E, ferritin, TSH, FSH, LH, oestrogen, β-hCG. CA-125 is debatable in routine work-up, as elevated levels occur with benign large fibroids — tumour markers have a more accurate role in follow-up after treatment. Ultrasound (transvaginal and transabdominal); MRI is becoming more prominent and is more specific than CT.

Management

Conservative: appropriate for asymptomatic women or slow-growing fibroids — expectant management with annual review and serial ultrasound for those who decline treatment and have no significant complications.

Medical (for the associated menorrhagia, not the fibroid itself): tranexamic acid and NSAIDs give marginal benefit; an IUD can help, though insertion may be difficult depending on fibroid size/distortion; a GnRH agonist can reduce fibroid size/vascularity, but symptoms typically recur once treatment stops, and side effects limit use.

Surgical and procedural options

Uterine artery embolisation (UAE): contraindicated in current pregnancy or active/recent pelvic infection. Complication rates: minor ~30–45%, major (life-threatening/permanent sequelae/needing surgery) ~5%; VTE is rare (~0.3%); deaths are exceptionally rare (5 case reports across >11,000 patients in the literature, none since 2009).

Longer-term outcome data (EMMY trial, 10-year follow-up): ~35% of women who chose UAE eventually had a hysterectomy (5% for immediate failed bilateral UAE, a further 19% by 2 years for inadequate response, another 10% between 2–10 years for persisting symptoms) — i.e. ~65% avoid hysterectomy long-term, but the re-intervention rate is high enough to potentially offset UAE’s initial cost/recovery advantage. Counsel patients accordingly, and that they should be prepared to accept possible hysterectomy if complications occur.

Fertility caution: avoid routine UAE in young women who wish to conceive — the one RCT comparing UAE with myomectomy found higher pregnancy rates and lower miscarriage rates with myomectomy, and UAE’s effects on fertility/ovarian reserve (reduced AMH/antral follicle count post-procedure) remain uncertain. Myomectomy is preferred if future fertility is a priority; UAE should only proceed after fully informed discussion if a woman desiring pregnancy still wants it.

Pedunculated/narrow-stalked submucosal or subserosal fibroids can detach and slough post-UAE — plan for possible hysteroscopic/laparoscopic retrieval, or consider elective surgery instead for these.

MRI-guided focused ultrasound: a newer technique with promising trial data — focused heat denatures fibroid cells to reduce fibroid size.

Myomectomy: benefit depends on fibroid location, not just presence — submucosal fibroids reduce fertility and increase miscarriage risk, and hysteroscopic myomectomy likely improves outcomes; intramural fibroids may also reduce fertility, but evidence that myomectomy specifically helps is insufficient; subserosal fibroids don’t meaningfully affect fertility. MRI, sonohysterography or hysteroscopy are needed to assess cavity involvement accurately — transvaginal ultrasound and HSG aren’t sensitive/specific enough. New fibroids can regrow over time regardless of technique.

For women trying to conceive, medical management (including GnRH agonists) is not a fertility treatment — it delays conception attempts — though short-term pre-operative GnRH agonist use (anaemia correction, shrinking the fibroid before surgery) is reasonable. Ulipristal acetate is not recommended in infertile women, given significant adverse-effect risk (hepatotoxicity monitoring requirements).

Hysterectomy gives the best outcome for symptom reduction.