progestogen only pill and breast cancer

Last reviewed 03/2021

The excess number of breast cancer diagnoses in recent and current users of the progestogen only pill (POP) users is small in relation to the overall risk of breast cancer, possibly of similar magnitude to that associated with the combined oral contraceptive pill (1)

• in comparison to never-users, among 10,000 women who use POPs for up to 5 years but stop by age 20, the evidence suggests there would be less than 1 extra case of breast cancer diagnosed up to 10 years afterwards
  
  
• in comparison to never-users, among 10,000 women who use POPs for 5 years but stop by age 30, there would be an estimated 2-3 extra cases diagnosed up to 10 years afterwards
  
  
• in comparison to never-users, among 10,000 women who use POPs for 5 years but stop by the age of 40, there would be an estimated extra 10 cases diagnosed up to 10 years afterwards

A more recent review states '..The available evidence does not support an association between breast cancer and use of a POP. However, due to the limited available evidence, an increased risk cannot be completely excluded. Any increased risk is likely to be small and to reduce with time after stopping...' (2)

Reference:

• Current Problems in Pharmacovigilance (1998), 24, 1.
• FSRH (March 2015). Progestogen-only pills.