Screening Tests for Ovarian Cancer

When you need them—and when you don’t

If a woman has symptoms that might be related to ovarian cancer, health care providers often order an ultrasound of the pelvic area and a blood test called a “CA-125.” However, these tests are not good for screening asymptomatic patients who are considered “low risk.” Here’s why:

The test results are not always correct.

About half of the women with early staged ovarian cancer have a normal CA-125 level, which could be falsely reassuring. CA-125 have low sensitivity and specificity. Women with a high CA-125 level don’t always have ovarian cancer. Instead, they may have another cancer or a different medical condition such as cirrhosis, pelvic inflammatory disease, fibroids, endometriosis, diverticulosis or congestive heart failure.

Ultrasounds are also not accurate at finding early ovarian cancer. They often show cysts that are benign (not cancer) and can lead to unnecessary surgery.

The tests can lead to risky procedures.

If a CA-125 test or an ultrasound shows something that isn’t normal, health care providers will consider surgery that may result in the ovary and/or other organs being removed. There’s a risk of injury, even with minimally invasive surgery done through a tiny cut with very small surgical tools.

Some women choose to have both ovaries removed during the procedure. This can cause early menopause, which can increase the risk of side effects related to early menopause such as hip fractures, heart attacks, and possibly dementia.

The tests and follow-up can be costly.

The tests can add costs and negatively affect your quality-of-life without any true/real benefits. A CA-125 blood test can cost $200 or more, while an ultrasound costs $150 to $250. Surgery costs a lot more. There may be added costs for hormone replacement therapy that may be used for many years depending on the individual’s age and symptoms.

When are the tests worth the risks?

The CA-125 test and an ultrasound may be helpful if you have symptoms of ovarian cancer such as abdominal bloating, early satiety, or pelvic pain.

Also, if your health care provider feels something abnormal on a physical exam, these tests may help diagnose the problem.

If you already have ovarian cancer, the CA-125 test can be helpful to see if treatment is working or if the cancer has come back.

So, what should I do instead?

You should talk to your health care provider if you believe you are at increased risk for ovarian cancer. People with family members who have been diagnosed with ovarian, breast, uterine, or colon cancer may be at higher risk, especially if they have multiple family members who have been affected. If you know relatives diagnosed with these cancers that have been found to have a genetic cause for their cancer, you should certainly speak with a health care provider about this.

In summary, CA-125 and pelvic ultrasounds are not good tools for low-risk women. They may be helpful for women with a known high risk of developing ovarian cancer. CA-125 is often used for women with known ovarian cancer to monitor treatment and watch for recurrence.


This report is for you to use when talking with your healthcare provider. It is not a substitute for medical advice and treatment. Use of this report is at your own risk.

© 2021 ABIM Foundation. Developed in cooperation with the Society of Gynecologic Oncology.