From the American Cancer Society: http://www.cancer.org/cancer/ovariancancer/overviewguide/ovarian-cancer-overview-found-early
Screening
Screening tests and exams are used to find a disease such as cancer in people who don’t have any symptoms. Women with a very high risk of ovarian cancer (such as those with a strong family history of the disease) may be screened with ultrasound and with a certain blood test. But studies of women at average risk of ovarian cancer show that these tests did not lower the number of deaths caused by ovarian cancer. For this reason, these tests are not used to look for ovarian cancer in women who aren’t high risk.
Ways to help find ovarian cancer early
Regular women’s health exams
During a pelvic exam the doctor will feel the woman’s organs to check their size and shape. But most ovarian tumors are hard to find early because the ovaries are deep within the body and it isn’t easy for the doctor to feel them. The Pap test helps to find cervical cancer early, but it is not really useful for finding ovarian cancer early.
See a doctor if you have symptoms
Symptoms of ovarian cancer can include swelling or bloating, pain in the belly, trouble eating, and bladder symptoms (feeling as if you have to go often or always feeling as if you have to go).
These symptoms are most often caused by something besides ovarian cancer. Sometimes when ovarian cancer is the cause, the symptoms are more severe, but that isn’t always true. What is most important is that they are a change from how a woman usually feels.
Still, early cancers of the ovaries often cause no symptoms.
I expect that the "certain blood test" referred to in the screening paragraph is the CA-125 test.
Lots of information about the test here,
Questions and Answers About the CA-125 Test, from Johns Hopkins Pathology, including this:
CA-125, cancer antigen-125, is a protein that is found at levels in most ovarian cancer cells that are elevated compared to normal cells. CA-125 is produced on the surface of cells and is released in the blood stream.
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The CA-125 test only returns a true positive result for about 50% of Stage I ovarian cancer patients. The CA-125 test is not an adequate early detection tool when used alone.
The CA-125 test has an 80% chance of returning true positive results from stage II, III, and IV ovarian cancer patients. The other 20% of ovarian cancer patients do not show any increase in CA-125 concentrations.
Best wishes. Good fortune. Safe home.
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