Ovarian cancer is rare in young women, but the incidence starts to rise sharply after menopause.

There is a clear genetic predisposition for ovarian cancer, so that women who have a first-degree relative with ovarian cancer are much more likely to get this tumour themselves. Other familial cancers that have been co-related with an increased risk of ovarian cancer include breast cancer, uterine cancer, colon cancer, and prostate cancer. The risk of ovarian cancer is also increased in women who have had breast cancer, likely as a result of carrying one of the BRCA genes.

A diet high in meat raises the risk, while a diet high in fruits and veggies seems to protect against ovarian cancer, but perhaps only if such a diet is followed from the teen years on. It's less clear that a "good" diet helps reduce the risk of ovarian cancer if it's begun during midlife.

There is a significantly lower incidence of ovarian cancer in women who take contraceptive pills, a beneficial effect that kicks in very quickly after a woman starts on the pill, so that taking the pill for only 3 years reduces a woman's chance of developing ovarian cancer by up to 50%. Pills with higher doses of progestin in them may provide better protection than pills with less progestin.

Pregnancy lowers the risk of ovarian cancer, as does tubal ligation, and recent studies suggest that other types of birth control such as barrier methods and vasectomy may also reduce the risk somewhat.

Long-term use of hormone replacement therapy (HRT) increases the risk of ovarian cancer, with the risk climbing the longer a woman is on HRT.

There is some evidence that long-term use of ASA lowers the risk of ovarian cancer, leading to the theory that at least part of the reason cancer develops in the ovaries is through inflammation, which is suppressed by ASA.

Although studies have suggested that infertility and the use of fertility medications might raise the risk of ovarian cancer, more recent studies have failed to confirm those links.

Art Hister, MD 
in association with the MediResource Clinical Team