Experts do not know exactly what causes ovarian cancer. Genetics, such as DNA changes, are a risk factor for some women.

A family history of ovarian or breast cancer is found in 10% to 20% of women with ovarian cancer.¹ In general, fewer than 2 out of 100 women (less than 2%) will get ovarian cancer in their lifetime. That risk goes up to 4 or 5 out of 100 if one family member has had ovarian cancer, and 7 out of 100 if two relatives have had it. But if at least two first-degree relatives (meaning mother, sister, or daughter) have had ovarian cancer, the risk is 25 to 50 out of 100 (25% to 50%).²

Women who inherit changes (genetic mutations) in the BRCA1 and BRCA2 genes have a higher chance of developing ovarian cancer and breast cancer. Women who inherit the gene change in BRCA1 have a lifetime chance of 20 to 60 out of 100 of getting ovarian cancer. For women who inherit the gene change in BRCA2, the lifetime chance is 10 to 35 out of 100.³

You have a higher chance of developing ovarian cancer if you:

• Are unable to become pregnant (infertility).
• Have never had a baby.
• Have not used hormonal birth control methods. Hormonal methods change the normal cycle of the female hormones, estrogen and progesterone, so ovulation does not occur each month.

If you have a strong family history of ovarian or breast cancer, you may want to talk with your doctor or a genetic counselor about having a blood test to look for BRCA1 and BRCA2 gene changes. Women who inherit these changes in one or both of these genes have a higher chance of developing ovarian cancer, breast cancer, or both.