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Ovarian Cancer - Prevention

There is no sure-fire method of preventing ovarian cancer. There is also no foolproof screening test to detect ovarian cancer. The best method of defense against ovarian cancer is a yearly pelvic exam beginning at age 18. Physicians perform pelvic exams to check for abnormalities in the size or shape of the uterus, vagina, ovaries, Fallopian tubes, bladder, and rectum. Many women mistakenly believe that the Pap smear exam screens for ovarian cancer; however, the Pap smear is a screening exam for cervical cancer. The Pap smear may occasionally detect ovarian cancer but usually only after it has progressed to advanced stages.

Women should also be aware of their family history and inform their physicians of any risk factors that may put them at higher risk for ovarian cancer. Because the symptoms of ovarian cancer can be subtle, many cases of ovarian cancer are not diagnosed until late stages when the chances for survival are much lower. Therefore, it is important for women to become familiar with the symptoms of ovarian cancer so they can report them to their physicians. Click here to learn more about symptoms of ovarian cancer.

Genetic testing is available to determine whether women carry mutations of the BRCA1 (breast cancer gene 1) or BRCA2 (breast cancer gene 2) genes. Mutations of these genes put women at higher risk of developing both ovarian cancer and breast cancer. The decision to undergo genetic testing is a personal one and should be made carefully with input from physicians and family members. Many women also undergo genetic counseling before the test.

While some women do not wish to know if they carry mutations of genes that put them at higher risk of ovarian cancer, the test does help some women to weigh options to reduce their risk of developing ovarian cancer. Women should discuss the benefits and risks of these preventive options with their physicians before pursuing them; they should also be aware that no option can eliminate the chances of developing ovarian cancer.

The following have been shown to provide some protective effect against ovarian cancer. However, some of these options should obviously not be pursued for the sole purpose of preventing ovarian cancer.

Pregnancy and breast-feeding: Pregnancy seems to decrease the risk of both ovarian and breast cancer if a woman becomes pregnant with her first child before age 30. This is because there is an interruption of menstrual cycles during pregnancy. Women who never become pregnant are at a higher risk of ovarian cancer and breast cancer than those who have a child before age 30. Likewise, breast-feeding also decreases the risk of ovarian and breast cancer because menstruation is interrupted.

While pregnancy at a young age decreases ovarian cancer and breast cancer risk, pregnancy after age 30 appears to increase the risk of ovarian cancer and breast cancer. The older a woman is, the more likely her ovarian and breast tissues have already been exposed to some cancer-causing substances called carcinogens. Therefore, exposure to elevated hormone levels during pregnancy at a later age may stimulate the growth of abnormal ovarian or breast tissue.

Birth control pills: Research shows that women who take birth control pills (oral contraceptives) seem to be at lower risk for ovarian cancer. The risk appears to be greater the longer a woman takes birth control pills. The American Cancer Society estimates that women who take birth control pills for at least five years decrease their chances of ovarian cancer by 60%.

Tubal ligation or hysterectomy: Procedures to tie the Fallopian tubes (tubal ligation) or remove the uterus (hysterectomy) lower the risk of ovarian cancer. However, because of the risks and potential complications of these procedures, they should only be performed for medical reasons and not solely to reduce the risk of ovarian cancer.

Removal of the ovaries: Removing the ovaries (oophorectomy) may decrease the risk of ovarian cancer and breast cancer. However, the procedure remains controversial and is not commonly performed. The theory is that removing the body’s main source of estrogen (the ovaries) helps reduce the chances of developing both ovarian and breast cancer since many of these cancers depend on estrogen for growth and survival. A 2010 study published in the Journal of the American Medical Association showed a reduced risk of ovarian cancer among women at genetically high risk of developing the disease who underwent oophorectomies. Early research, published in 2011 in the journal Human Reproduction, however finds that researchers may eventually be able to leave the ovaries in tact. The researchers found that removing the removing a layer of cells on which ovarian cancer cells tend to form reduced cancer risk while maintaining fertility. Further research is needed to verify the findings in humans.

Updated: June 2011