Does Taking Birth Control Pills Really Raise the Risk of Breast Cancer by 50%?

Headlines around the world this week have focused on a new study that links the use of high-dose estrogen birth control pills within the past year to a 50% increased risk of developing breast cancer. But while the headline “Taking the Pill ‘raises the risk of breast cancer by 50 per cent’” might earn lots of clicks, is it an accurate portrayal of the study’s findings?

A few very important things to note:

  • The study only looked at women aged 20-49—an age group in which instances of breast cancer is very low. Even if taking certain oral contraceptives does raise the risk of breast cancer by 50%, the overall risk is still incredibly low—less than 1%.
  • The pills that were shown to raise the risk of 50% are high-estrogen pills and are not prescribed very often. In this particularly study, only 1% of the study’s participants took high-estrogen birth control pill within the past year.
  • Low-dose estrogen pills—those prescribed to 24% of the study’s participants were not associated with any increased risk of breast cancer.
  • Other studies have suggested that birth control pills can lower the risk of ovarian, endometrial, and colorectal cancers and help protect against pelvic inflammatory disease.

Once again, sensationalism trumps factual reporting. Even the lead author of the study says that the study shouldn’t discourage women from taking birth control pills. So the results should “trouble women on birth control pill”—they should keep in mind the words of UNC School of Medicine’s Dr. David Grimes: “The best studies, done by the Centers for Disease Control and funded by the National Institutes of Health, have consistently found no association between oral contraceptives and breast cancer.”