To review recent literature on health outcomes associated with use of hormonal contraception with a focus on breast cancer.
A large cohort study documented an increased risk of breast cancer among hormonal contraceptive users compared to those who had never used hormonal contraception. The overall relative risk of breast cancer among current or recent users was 1.2 [95% confidence interval (CI), 1.14-1.26]. Overall, this translates into one additional case of breast cancer for every 7690 users of hormonal contraception. Recent publications have also documented a decrease in risk for endometrial, ovarian, and colorectal cancers among hormonal contraceptive users. Based on these data, it is estimated that a third of endometrial and ovarian cancers and a fifth of colorectal cancers were prevented with combined oral contraceptive use.
Several factors must be taken into consideration regarding the risk of breast cancer associated with hormonal contraceptive use. Contraceptive benefits related to preventing unintended pregnancy are protective against associated maternal morbidity and mortality. Noncontraceptive benefits of protecting against other types of cancers must also be considered. Overall, breast cancer risk is low among hormonal contraceptive users and women should be counseled accordingly.