What Blood Test Tests for Ovarian Cancer? Guide

A blood test for ovarian cancer does not exist as a standalone screening tool, but several biomarker tests—such as CA-125, HE4, and the ROMA index—are used to assess risk and guide diagnosis. Today, these tests remain the most common blood-based options for evaluating ovarian cancer, though they are often combined with imaging and pelvic exams for a complete picture. This guide explains the key blood tests, their accuracy, and when you might consider them.

Understanding Blood Tests for Ovarian Cancer

Ovarian cancer is often called the “silent killer” because symptoms are vague and appear late. Blood tests that measure specific proteins (biomarkers) can help detect cancer early or monitor treatment. Here are the primary options:

CA-125 Blood Test

CA-125 (cancer antigen 125) is the most well-known biomarker. Elevated levels may indicate ovarian cancer, but also benign conditions like endometriosis, pregnancy, or pelvic inflammatory disease. It is most useful for monitoring women already diagnosed with ovarian cancer, not for general screening.

HE4 and the ROMA Index

HE4 (human epididymis protein 4) is more specific than CA-125 for ovarian cancer, especially for epithelial tumors. The ROMA (Risk of Ovarian Malignancy Algorithm) index combines CA-125 and HE4 levels with menopausal status to calculate risk. This improves accuracy and reduces false positives.

OVA1 and Multivariate Assays

OVA1 is a panel of five biomarkers (CA-125, beta-2 microglobulin, transferrin, prealbumin, and apolipoprotein A1) analyzed by a proprietary algorithm. It is approved for women with a pelvic mass to determine if surgery is needed. Similar tests like Overa and Multivariate Index Assay (MIA) are also used.

When Are These Blood Tests Recommended?

Blood tests are not recommended for routine screening in average-risk women due to low sensitivity and specificity. However, they are used in specific scenarios:

For Women with Symptoms

If you have persistent bloating, pelvic pain, difficulty eating, or urinary urgency, a doctor may order a blood test along with a transvaginal ultrasound. This combined approach helps differentiate benign from malignant masses.

As Part of a Screening Strategy for High-Risk Women

Women with a strong family history of ovarian or breast cancer, or those with BRCA1/BRCA2 mutations, may benefit from regular blood tests and imaging starting at age 30-35. The goal is early detection, though no national guidelines recommend universal screening.

Other Diagnostic Tools for Ovarian Cancer

• Transvaginal ultrasound: Visualizes ovarian masses and evaluates their structure.
• Pelvic exam: Manual examination to detect lumps or enlargement.
• Biopsy: Surgical removal of tissue for definitive diagnosis.
• Genetic testing: Identifies inherited mutations that increase risk.

Comparison of Common Blood Tests

How to Prepare for Your Blood Test

Most ovarian cancer blood tests require no special preparation, but check with your lab. Avoid strenuous exercise 24 hours before—it can spike CA-125. Inform your doctor about any medications or supplements. Fasting is not typically needed, but follow specific instructions if you’re taking a multi-marker panel.

Take the Next Step with AnyLabTestNow

If you're concerned about ovarian cancer risk, talk to your healthcare provider. They can order the appropriate blood test based on your symptoms and history. For convenient, affordable testing, visit our ovarian cancer blood test order page to learn more about available panels and how to get tested without a doctor’s referral in most states. Early detection saves lives—take control of your health today.