Abortion, Breast Cancer, and Epidemiology

In this issue of the Journal, ¹ Melbye et al. present substantial epidemiologic evidence that induced abortions do not affect a woman's risk of having breast cancer. In a linkage study, they compared the abortion histories of women with and without breast cancer in Denmark. The use of data on abortion obtained from population registries rather than from interviews, the large size of the study, the inclusion of one country's entire population of women, and the adjustment for other aspects of reproductive history all strengthen the credibility of the findings. The study thus provides important new evidence to resolve a controversy . . .