Epidemiologic Findings
…snip…
Induced abortion is not associated with an increase in breast cancer risk. (1)

*Strength of Evidence Ratings Key

Strength of Evidence Ratings: Epidemiology
1 = Well established
2 = Weight of evidence favors
3 = Suggested from human population studies, but speculative
4 = Suggested from laboratory or theoretical considerations but essentially unevaluated in human populations

cancer.gov