In a way this is because of how the medical profession has presented the risk of developing ovarian cancer. Everyone is scared of developing cancer but is the risk that great considering other illnesses that may also happen for example 20 in 100 women will die of lung cancer, and 33 in 100 will die of heart disease (figures are greater than the mortality from ovarian cancer
Ovarian cancer though relatively rare, is more common in women who have continued to produce eggs without interruption through their reproductive life. Factors that decrease ovulation help decrease the risk of ovarian cancer
What is the risk?
The lifetime risk of developing ovarian cancer in the general population is 1:70, put another way if a woman were to live to 90 the risk of developing ovarian cancer would be 1.4%.
About 1:100 women will develop ovarian cancer.
- If a first-degree relative e.g. sister has ovarian cancer that risk increases to about 5:100.
- If ones grandmother or aunt has or developed ovarian cancer the risk is about 3:100
- With 2 or more relatives with ovarian cancer the risk increases to 14:100
Factors that decrease the risk of ovarian cancer include:
1. Taking the oral contraceptive pill for more than a year decreases the lifetime risk to 1:140, decreasing the risk by about 10%. Taken for 5years or more it can decrease the risk by 50-70%
2. Late onset of periods decreases the risk to about 1:80
3. Menopause before the age of 45 years decreases the risk to about 1:85
4. Having one or more children decreases the risk to about 1:140
5. Breast feeding decreases the risk
6. Tubal sterilization decreases the risk by about 30%
7. Hysterectomy decreases the risk by 50%
A family history of ovarian cancer increases the risk, however this again needs to be taken in context as less than 10% of ovarian cancers are in women who are susceptible due to genetics. In women with the gene implicated in ovarian cancer may have up to a 50% chance of developing ovarian cancer and are sometimes advised to have their ovaries removed once they have completed their families.
The risk of ovarian cancer needs to be weighed against the risk of other things that can occur once the ovaries are removed. Therefore in the absence of a strong family history or in some cases severe endometriosis with pelvic pain, it is always better to keep ovaries.