The birth control pill (BCP) or oral contraceptives, when used before age 20, significantly increase risk of early-onset breast cancer (diagnosed before age 36). If the BCP is used consistently for 10-20 years before the age of 45, it can cause a 42% increased risk of breast cancer in a user.
- Impact of teenage oral contraceptive use in a population-based series of early-onset breast cancer cases who have undergone BRCA mutation testing.
- Oral contraceptives and breast cancer: review of the epidemiologic literature.
- Oral contraceptive use at a young age and the risk of breast cancer: an Icelandic, population-based cohort study of the effect of birth year.
- Differences in reproductive risk factors for breast cancer in middle-aged women in Marin County, California and a sociodemographically similar area of Northern California.
- Reproductive and hormonal risk factors for ductal carcinoma in situ of the breast
- A case-control study of oral contraceptive use and incident breast cancer.