Fibroids
Overview
Fibroids (uterine leiomyomata) are benign monoclonal smooth muscle tumours of the myometrium. Hormone-dependent (oestrogen + progesterone), presenting during reproductive years and regressing after menopause.
Classification
Location is the key determinant of symptoms and surgical approach: submucosal (distorts cavity - worst for bleeding/fertility), intramural (within myometrium), subserosal (projects outward - mass/pressure symptoms).
Presentation
•Menorrhagia - most common symptom; heavy, prolonged, often clotted bleeding
•Dysmenorrhoea - abnormal uterine contractions around fibroid
•Urinary frequency/urgency - anterior fibroids compress bladder
•Constipation - posterior fibroids compress rectum
•Subfertility - submucosal fibroids distort cavity impairing implantation; intramural fibroids may obstruct fallopian tube ostia
•Enlarged, irregular, non-tender uterus - firm, irregular suprapubic mass on bimanual examination
•Iron deficiency anaemia - secondary to chronic menorrhagia
Investigations
🥇 First-line
•transvaginal ultrasound (TVS) - identifies location, number, size; transabdominal if uterus large
•FBC - assess for iron deficiency anaemia
🥈 Second-line
•MRI pelvis - surgical planning, superior characterisation, excludes adenomyosis
•hysteroscopy - direct visualisation and characterisation of submucosal fibroids; allows simultaneous diagnosis and treatment
Management
Asymptomatic fibroids - reassurance and observation only. Symptomatic management guided by symptoms, fibroid characteristics, and desire for fertility/uterine preservation.
First-line · Medical
- 1Levonorgestrel intrauterine system (LNG-IUS) - first-line for menorrhagia; only if no significant cavity distortion (risk of expulsion)
- 2Tranexamic acid - antifibrinolytic; non-hormonal option for menorrhagia
- 3NSAIDs (e.g. mefenamic acid) - reduce prostaglandin-mediated menorrhagia and dysmenorrhoea
Second-line · Medical/Surgical
- 1Combined oral contraceptive pill or oral/injectable progestogens - hormonal cycle control
- 2GnRH analogues (e.g. goserelin) - shrink fibroids 30-50%; pre-operative use or approaching menopause; max ~6 months (bone density loss); add-back HRT may extend use
- 3Endometrial ablation - for completed family only; pregnancy contraindicated post-ablation; most effective when fibroids small and cavity not distorted
- 4Myomectomy - fertility-preserving surgical option; hysteroscopic (submucosal), laparoscopic, or open; recurrence ~15-33% within 5-10 years; ~10% ultimately require hysterectomy
Third-line
- 1Ulipristal acetate - selective progesterone receptor modulator; restricted use only (surgery/UAE unsuitable or failed); risk of serious hepatotoxicity/liver failure (MHRA 2021)
- 2Hysterectomy - definitive treatment; indicated when fibroids numerous, symptoms severe, or other treatments failed; ovarian conservation preferred
Interventional radiology
- 1Uterine artery embolisation (UAE) - femoral access, bilateral uterine artery occlusion with embolic particles (polyvinyl alcohol); fibroids undergo ischaemic necrosis and shrink; uterus-preserving
- 2UAE not recommended as primary option in women wishing to conceive - uncertain effects on ovarian reserve, obstetric outcomes; ~one third require re-intervention within 5 years
Complications
•Red degeneration - haemorrhagic infarction of fibroid during pregnancy (outstrips blood supply); presents with acute localised uterine pain, low-grade fever, leucocytosis in 2nd/3rd trimester; management is conservative (paracetamol first-line; NSAIDs with caution); resolves spontaneously
Referral thresholds
•Fibroids ≥3 cm diameter on imaging, or suspected submucosal fibroids
•Severe menorrhagia or compressive symptoms not controlled in primary care
•Suspected fertility or obstetric complications
•Rapid/unexpected growth post-menopause - urgent referral to exclude malignancy
•Women with symptomatic fibroids requesting HRT - specialist advice first (HRT may stimulate fibroid growth)