CA 125 — The Ovarian Health Checkpoint

CA 125 is a protein produced by cells of the ovaries, uterus and the lining of the abdominal cavity. It is raised in many women with ovarian cancer, but also in endometriosis, fibroids, pelvic inflammatory disease, liver cirrhosis, pregnancy and during menstruation. Because so many benign conditions raise it, the value is interpreted alongside examination and imaging and never on its own.

Why Test CA 125?

The CA 125 test helps doctors evaluate suspected ovarian cancer, keep tabs on treatment response in women already diagnosed, and spot recurrences after treatment. It can also be relevant for other gynaecological cancers and some gastrointestinal and lung cancers — though it is not cancer-specific on its own.

What Do High CA 125 Levels Mean?

High CA 125 (typically above 35 kU/L) may point to ovarian cancer, especially when combined with symptoms or imaging findings. But elevated levels also show up in uterine, pancreatic, lung, or breast cancer — and in non-malignant conditions like endometriosis, liver cirrhosis, or pelvic inflammatory disease. A high number does not equal a cancer diagnosis. It means it is time to dig deeper with imaging and possibly a biopsy.

What Do Low CA 125 Levels Mean?

A normal CA 125, typically below 35 kU/L, makes significant disease activity less likely and, during treatment, suggests it is working. Not all ovarian cancers produce CA 125, particularly at an early stage, so a normal value does not exclude cancer. The test is most informative when tracked over time in someone with a known raised level.

Symptoms to Watch For

Persistent bloating or abdominal swelling
Pelvic or abdominal pain
Difficulty eating or feeling full quickly
Unexplained weight loss or gain
Changes in bowel or urinary habits

Who Should Get Tested?

People being investigated for ovarian cancer after a doctor's assessment or an imaging finding
People monitoring treatment for a known ovarian cancer
People in follow-up after treatment
Not recommended as a screening test without symptoms: it has not been shown to reduce deaths from ovarian cancer, and false positives lead to unnecessary surgery

How to Prepare for Your Test

No special prep needed. Just bring valid ID to your appointment.

Order Your Blood Test

Test your CA 125 levels with an accredited Swedish laboratory. Results within days, reviewed by Wellth.

Ovarian Cancer Test →

Frequently Asked Questions

Is CA 125 a reliable screening test for ovarian cancer?

No. It is raised in too many benign conditions to be useful for screening the general population, and trials have not shown that screening reduces deaths from ovarian cancer. Its established uses are monitoring known cancer, detecting recurrence, and assessing symptoms alongside examination and imaging.

Can CA 125 be elevated without cancer?

Absolutely. Endometriosis, fibroids, pelvic inflammatory disease, liver cirrhosis, and even menstruation or pregnancy can all push CA 125 up.

How often is CA 125 monitored during cancer treatment?

Your oncologist will typically check it before each treatment cycle or at regular intervals to see how things are going and to catch any signs of progression early.

Does a normal CA 125 level mean I am cancer-free?

Not necessarily. Some ovarian cancers do not produce CA 125, especially in early stages. A normal result is encouraging but should always be considered alongside other diagnostic findings.

Reviewed by

Wellth Team

Wellth

Our content is written and reviewed by Wellth, and fact-checked against peer-reviewed research and current Swedish clinical guidelines.

Learn more about our team →

Medical Disclaimer

The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.