Although oral contraceptives can have a downside or even be inadvisable for women with certain health problems, they are mostly without any significant drawbacks to daily, continuous use. There is no need for, nor benefit of taking a "pill holiday." Researchers feel that it is the continuous suppression of the normal ovarian cyclic function that accrues cancer risk. The specific type of pill and dose of estrogen or progestin does not seem to make a difference. The relationship between oral contraceptive use and breast cancer is muddy, and there are a few studies that show some increase in risk and others that show absolutely no change in overall risk. The NIH published a nice fact-sheet on this.
For women who have a first degree relative with ovarian cancer (mother or sister), getting genetic testing for BRCA 1 and 2 gene mutation is an option. The presence of this BRCA mutation greatly increases the risk of breast and ovarian malignancy in that woman's lifetime. She may be recommended to have removal of both ovaries at a relatively young age (once childbearing is complete if desired) in an effort to reduce the risk. Some of those at-risk women are placed on birth control pills until such time as they want to conceive because of the clear benefit for the rest of her life.
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