What Causes Ovarian Cancer?

This content has been reviewed and approved by

Maurie Markman, MD
Vice President, Clinical Research
MD Anderson Cancer Center
University of Texas

The exact cause of ovarian cancer is not known. But like other types of cancer, ovarian cancer develops when your body rapidly produces unnecessary cells. These out of control cells can form clumps (masses) inside of your ovary. Although many times the clumps (a benign mass) do not turn into cancer, cancer can form—most commonly in the epithelial cells on the surface of the ovary.

Doctors and researchers believe there are certain factors that raise your chances of getting the disease. These are called risk factors for ovarian cancer.

The chance of an individual developing cancer depends on both genes you inherit from your parents and environmental factors. Environmental factors may include diet, exercise, or exposure to other substances present in your surroundings.

Other cancers have no known environmental correlation, but are known to have a genetic (inherited) predisposition. A genetic predisposition means that a person may be at higher risk for a certain cancer if a family member has that type of cancer.

The following have been suggested as risk factors for ovarian cancer:

• Starting monthly periods early (before age 12)
• Late menopause (after 52 years old)
• Age (over 50)
• Hormone replacement therapy - some studies have suggested that women who use hormone replacement therapy after menopause may have a slightly increased risk of ovarian cancer
• Infertility (inability to become pregnant)
• Having a first child after 30
• Personal history of breast or colon cancer
• Family history
• First-degree relatives (such as mother, daughter, and sister) of a woman who has had ovarian cancer are at a risk for developing the disease. The risk increases if two or more first-degree relatives have had ovarian cancer. A family history of breast or colon cancer is also associated with an increased risk of developing ovarian cancer.
• Fertility drugs