Why Is There No Routine Screening for Ovarian Cancer?

It is incredibly frustrating that we do not have a routine screening test for ovarian cancer like we do for breast or cervical cancer. The short answer is that large, rigorous studies have proven that screening women at average risk does not save lives, but it does cause significant harm ^[1][2][3]. The tests currently available—specifically the CA-125 blood test and transvaginal ultrasound—generate too many false alarms in healthy women ^[4]. These false positives lead women to undergo unnecessary and risky surgeries to remove their ovaries, without ultimately preventing ovarian cancer deaths in the population ^[5][1].

What the Major Clinical Trials Showed

For years, doctors hoped that checking CA-125 levels and performing regular ultrasounds could catch ovarian cancer early enough to make a difference. To test this, researchers conducted two massive clinical trials:

• The UKCTOCS Trial: This UK study tracked over 200,000 women for more than 16 years ^[1]. While the screening did find some cancers earlier, it did not significantly reduce the number of women who died from the disease ^[1].
• The PLCO Trial: A similar massive study in the United States, called the Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial, also found no difference in ovarian cancer mortality between women who were screened and those who received usual care ^[2].

Because of these findings, major medical organizations, including the US Preventive Services Task Force (USPSTF), strongly recommend against routine ovarian cancer screening for women at average risk, concluding that the harms far outweigh the benefits ^[6][7].

The Problem of False Positives

A false positive happens when a test suggests you might have cancer, but you actually do not. Both CA-125 and transvaginal ultrasounds are highly prone to false positives in average-risk women ^[3].

• CA-125 is a protein found in the blood. While ovarian cancer can cause it to rise, many common, non-cancerous conditions—like endometriosis, fibroids, or even a normal menstrual cycle—can also cause high CA-125 levels ^[8][4]. Because it lacks specificity, relying on it as a standalone screening test in the healthy population is ineffective ^[4][9]. (Note: While CA-125 is not a good screening tool for healthy women, it is a highly effective and standard test for monitoring women who have already been diagnosed with ovarian cancer.)
• Transvaginal ultrasounds are good at spotting masses or cysts on the ovaries, but they cannot tell whether a mass is harmless (benign) or cancerous (malignant).

Because these tests raise so many false alarms, many women end up needing surgery just to find out for sure what the tests found.

Unnecessary Surgeries and Hidden Harms

When a screening test comes back abnormal, the only way to definitively diagnose or rule out ovarian cancer is to perform surgery to remove the ovary (an oophorectomy) and examine the tissue under a microscope.

Because of the high rate of false positives, routine screening causes many healthy women to undergo major surgery for harmless cysts ^[3][10]. These unnecessary surgeries carry real risks, including:

• Blood loss and infections ^[5]
• Bowel or organ injuries ^[11]
• Long-term complications from sudden surgical menopause ^[5]

The trials showed that a significant number of women suffered major complications from surgeries triggered by false positive screening tests ^[10].

Exceptions for High-Risk Women

It is important to note that these guidelines apply to women at average risk. If you have a strong family history (such as having a mother, sister, or daughter diagnosed with ovarian cancer or early-onset breast cancer), or if you carry a known genetic mutation like BRCA1, BRCA2, or Lynch syndrome, the rules are different ^[12].

For women at elevated risk, doctors often recommend intensified surveillance, genetic counseling, or risk-reducing surgeries (like removing the ovaries and fallopian tubes) ^[12][13].

What to Do Instead of Screening

If you are concerned about your risk, the best approach is to talk to your doctor about your family history. More importantly, pay attention to persistent changes in your body. Warning signs of ovarian cancer are often vague but include:

• Persistent bloating
• Pelvic or abdominal pain
• Difficulty eating or feeling full quickly
• Urinary urgency or frequency

If you experience these symptoms consistently for more than a few weeks, you should not ask for a “routine screening.” Instead, tell your doctor about your symptoms and ask for a diagnostic evaluation. This shifts the context from checking a healthy person to investigating a specific medical problem, which is exactly what these tests are designed to do.