Scientists have found that certain risk factors increase a woman's chance of developing the most common type of ovarian cancer, epithelial ovarian carcinoma, although in most cases this increased risk is very small. Most ovarian cancer cannot be explained by any known risk factors. More research in this area is needed to help determine why some women develop the disease and others do not.
If your mother, sister or daughter has had ovarian cancer, especially if they developed it at a young age, you are considered to have an increased risk of developing the disease yourself.
About 7 percent to 10 percent of ovarian cancers result from an inherited tendency to develop the disease. The same genetic abnormality that occurs in breast cancer (BRCA1, and to a lesser extent BRCA2) may also be found in ovarian cancers.
Most epithelial ovarian cancers develop after menopause. Menopause is considered to have occurred when a woman goes one year without a menstrual period. On average, menopause occurs at age 51 in the United States. Half of all ovarian cancers are found in women over the age of 60.
Although ovarian cancer is rare in younger women, the types that do occur tend to be easier to treat than the epithelial tumors that affect older women. This is in contrast to breast cancer, which tends to be more difficult to treat in younger women.
There seems to be a relationship between the number of menstrual cycles that occur in a woman's lifetime and her risk of developing ovarian cancer. For this reason, starting menstruation at an early age (before age 12), not having children or having your first child after age 30, and experiencing menopause after age 50 may increase your risk of ovarian cancer.
By the same reasoning, using oral contraceptives (birth control pills) appears to reduce the risk of ovarian cancer, especially after five years of use, perhaps because it stops the ovulation process. Having a hysterectomy, or surgical removal of the uterus, or tubal ligation (tying the tubes to prevent pregnancy) also seems to reduce the ovarian cancer risk.
Breast feeding slightly lowers the ovarian cancer risk, most likely because breast feeding may delay the start of the menstrual period after pregnancy.
If you have had breast cancer, your risk for developing ovarian cancer is increased. This may be because inherited mutations of certain genes may increase your risk of both types of cancers, or because of other common risk factors.
Some studies suggest that long-term use of a fertility drug (clomiphene citrate) may increase a woman's risk of developing borderline (grade 0) EOC, but this is still under investigation. Some research suggests that it is not the drug itself, but the underlying infertility, that increases the EOC risk.
It has been suggested that talcum powder applied directly to the genital area or on sanitary napkins may cause ovarian cancer, but this link is not well documented. The finding in some studies may relate to the fact that in the past talcum powder was sometimes contaminated with asbestos, a known cancer-causing mineral.
Reviewed by health care specialists at UCSF Medical Center.
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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