Women’s Health · Test Results

Raised CA-125 — Why a Pelvic Ultrasound Comes First

A raised CA-125 is frightening to read and frequently means something entirely benign. Here is what the number is, what raises it, and why imaging is the next step rather than the last word.

Woman holding a mug in a calm consultation room by a window

CA-125 is a protein measured in blood. It rises in some ovarian cancers, which is why the test exists — and it also rises in a long list of ordinary conditions, which is why a raised result on its own diagnoses nothing.

The single most useful thing to understand: CA-125 is not a screening test for ovarian cancer. It is not offered to the general population, because in women without symptoms it produces far more false alarms than genuine findings. It is used to help interpret symptoms, alongside imaging — never as a standalone verdict.

Context

What raises CA-125 besides cancer

Cause Notes
Endometriosis A common cause of a raised result, sometimes markedly so
Fibroids Frequently associated with mild elevation
Ovarian cysts, including benign ones Particularly when large or irritated
Menstruation and early pregnancy Normal physiological rises
Pelvic infection Inflammation of any kind can raise it
Liver disease, heart failure, recent abdominal surgery Conditions well outside the pelvis raise it too

Two further points that get lost. CA-125 is less reliable before menopause, because so many of the causes above are common in younger women. And it can be normal in some ovarian cancers — a normal result never overrides persistent symptoms.

The Pathway

Why the scan is the sensible next step

A blood number cannot tell you what is in your pelvis. An ultrasound can: it shows whether the ovaries look normal, whether a cyst is present, and if so whether it looks simple and benign or has features needing further assessment. It also finds the fibroids, endometriomas and other benign explanations that account for a great many raised results.

That is why the standard route after a raised CA-125 is imaging, interpreted together with the blood result and your symptoms — often using a calculated risk score that combines CA-125, the ultrasound appearance and menopausal status. The scan is the part that turns an ambiguous number into something a clinician can act on.

Your GP stays in charge of this

A raised CA-125 should be followed up with the GP who ordered it — they can arrange NHS imaging and, where indicated, refer you on an urgent pathway. A private scan can give you the imaging answer within days and a report to take with you, but it does not replace that appointment.

See your GP promptly regardless of any blood result if you have persistent bloating, feeling full quickly or loss of appetite, pelvic or abdominal pain, or needing to pass urine more often — particularly if these are new and happening most days. Those symptoms drive the pathway, not the number.

At IUS London

What the scan assesses

  1. 1
    BookingNo referral needed, and appointments are usually available within days. Bring your blood result if you have it. 30 minutes.
  2. 2
    The scanA transvaginal scan gives the clearest view of the ovaries and is the standard approach; transabdominal is available if you prefer, and both are often used together.
  3. 3
    What we assessBoth ovaries in detail, any cyst measured and characterised by its features, the womb and lining, fibroids and endometriomas, and free fluid in the pelvis.
  4. 4
    ResultsExplained on screen as we scan, with the written report usually with you within two hours — written so your GP or gynaecologist can act on it directly.
FAQs

Your questions answered

Does a raised CA-125 mean I have ovarian cancer?
No. Endometriosis, fibroids, benign cysts, infection, menstruation and conditions outside the pelvis all raise it. That is precisely why the result is interpreted alongside imaging and your symptoms rather than on its own.
How high is too high?
There is no single threshold that decides anything. What matters is the number read together with the ultrasound appearance, your menopausal status and your symptoms — which is why clinicians use a combined risk assessment rather than the value alone.
Should I ask for CA-125 as a screening test?
It is not recommended for screening women without symptoms, and screening the general population with it has not been shown to save lives. It generates false alarms that lead to anxiety and sometimes to surgery in healthy women.
Can CA-125 be normal with ovarian cancer?
Yes, in some cases. A normal result is reassuring but does not override persistent symptoms — report those to your GP whatever the number says.
How quickly should I have the scan?
Reasonably promptly, so the result stops being an open question. Speak to your GP about NHS imaging; if that involves a wait and you would rather not sit with the uncertainty, a private scan within days is a reasonable use of one.
What if the scan finds a cyst?
Most cysts are benign. The report describes its size and features — simple, complex, or with characteristics needing further assessment — which is what determines whether it needs monitoring, referral, or nothing at all.
Related

Where to go from here

SymptomsPelvic Pain — When to Scan

What the pattern of pain suggests and when it is urgent.

Read the guide →Your ScanTransabdominal or Transvaginal?

How the two approaches differ, and why the choice is yours.

Read the guide →FibroidsMonitoring Fibroids

When fibroids need watching and how surveillance works.

Read the guide →

Turn the number into an answer

Both ovaries assessed in detail with any cyst measured and characterised, plus the womb, lining and pelvis — explained on screen as we scan, with the written report usually within two hours to take to your GP.

From £159
Pelvic scan

Pelvic scan

5a Lucerne Mews
Kensington, London W8 4ED
3 mins from Notting Hill Gate

This article is general information about CA-125 results, not individual medical advice. A raised result should be followed up with the GP who ordered it, and persistent bloating, early fullness, pelvic pain or urinary changes need GP assessment whatever the number — see NHS guidance on ovarian cancer. CA-125 is not a screening test. We do not offer blood tests.

Written and clinically reviewed by the HCPC-registered sonographers who perform this scan at IUS London — a CQC-registered diagnostic ultrasound clinic (Provider ID 1-2775844974). Your own findings are explained to you at the scan and set out in your report.

Author: Yianni Kiromitis, Senior Sonographer, HCPC RA38415 — over 20 years’ experience in NHS and private ultrasound
Medically reviewed: 9 August 2026