Condition Comparison

Uterine Fibroid vs Ovarian Cyst

Same symptoms, different conditions: here's exactly how to tell them apart.

Uterine Fibroid

Benign (non-cancerous) muscle tumours that grow in or on the wall of the uterus. Very common in Black African women aged 30–50. Usually multiple.

VS

Ovarian Cyst

A fluid-filled or semi-solid sac that forms on or inside an ovary. Most are functional (harmless, resolve on their own); some are pathological.

Side-by-Side Comparison

FeatureUterine FibroidOvarian Cyst
LocationIn the uterine wall, cavity, or protruding outward from uterusOn or inside one or both ovaries
Tissue typeSolid muscle (smooth muscle cells)Usually fluid-filled sac; occasionally solid (dermoid, endometrioma)
Effect on periodsHeavy, prolonged bleeding; flooding; clotsOften no effect unless large or on both ovaries
Pain patternPelvic pressure, heavy dragging ache; sharp pain if degenerationOften none; sudden severe pain if rupture or torsion
Fertility impactCan block tubes or distort uterine cavityEndometriomas reduce ovarian reserve; torsion risks the ovary
Who gets itPredominantly Black women, 30–50; hormone-sensitive (oestrogen)Any woman of reproductive age; some post-menopause
Scan appearanceSolid hypoechoic mass within/attached to uterusAnechoic (dark) simple cyst or complex cyst on ovary
Risk of cancerUterine sarcoma is rare (<0.5%); most fibroids are benignMost cysts are benign; complex cysts in post-menopausal women need evaluation
TreatmentHormonal therapy, Ulipristal, myomectomy, UAE, hysterectomyWatchful waiting for functional cysts; surgery for large or complex cysts

Symptoms They Share

⚠️ Both conditions can cause:

  • Pelvic fullness, heaviness or bloating
  • Lower abdominal pain or discomfort
  • Pressure on the bladder (frequent urination)
  • Difficulty getting pregnant
  • Abdominal swelling if large

The Key Difference

💡 How to tell them apart

Location on ultrasound tells the story instantly. A fibroid is attached to or within the uterine wall, the sonographer will trace it as part of the uterus. An ovarian cyst sits separately on an ovary and has its own blood supply. Clinically: heavy, prolonged periods with clots and a dragging pelvic ache in a 30–50-year-old Black Nigerian woman strongly suggests fibroids. A sudden sharp one-sided pain in a younger woman, especially mid-cycle, leans toward an ovarian cyst, particularly a ruptured follicular cyst or ovarian torsion (which is an emergency).

Which Tests Diagnose Each?

🧪 Pelvic Ultrasound (Abdominal + Transvaginal)
The definitive test for both. A skilled sonographer can distinguish a fibroid from an ovarian cyst with high accuracy, map fibroid number/size/position (submucosal, intramural, subserosal), and classify cysts by their internal structure (simple, complex, dermoid, endometrioma).
🧪 CA-125 Blood Test
Ordered if an ovarian cyst looks complex or suspicious, to help assess the risk of malignancy, especially in post-menopausal women. Not useful for fibroid diagnosis.
🧪 Full Blood Count (FBC)
Checks for anaemia caused by heavy fibroid-related bleeding. A low haemoglobin level guides urgency of treatment.
🧪 MRI Pelvis
Used pre-operatively to map fibroid size and type precisely, or to characterise complex ovarian masses when ultrasound is inconclusive.

Frequently Asked Questions

Can a fibroid be mistaken for an ovarian cyst on scan?
Rarely, if a fibroid is pedunculated (growing on a stalk from the outer uterine surface) and sits near an ovary, it can be confused with an ovarian mass. An experienced sonographer will trace the stalk back to the uterus to confirm. A second opinion scan is worth seeking if the report is uncertain.
Do fibroids become cancer?
Uterine fibroids are almost always benign. Uterine sarcoma, a malignant tumour, can resemble a fibroid on scan but is rare (less than 1 in 1,000). Rapid fibroid growth after menopause, extreme pain, or a very large soft mass warrants further evaluation.
Will my ovarian cyst go away on its own?
Simple functional cysts (follicular or corpus luteum cysts), which form as part of the normal menstrual cycle, typically resolve within 4–8 weeks without treatment. Complex cysts (dermoids, endometriomas, haemorrhagic cysts) are less likely to resolve and often require monitoring or surgery.
Can I get pregnant with fibroids or a cyst?
Yes, many women conceive naturally despite fibroids or cysts. However, submucosal fibroids (inside the uterine cavity) significantly reduce implantation success and often need to be removed before IVF. Large ovarian endometriomas reduce ovarian reserve and may need surgical treatment before fertility treatment.

Not sure which one you have?

Our doctors will review your symptoms and order exactly the right tests, no guesswork, no delay.

Last updated 16 October 2026.