Cause
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.