I have heard it said on multiple shows of Catholic Answers Live and read on Pro Life websites that abortion (and the Pill) increase the risk of breast cancer. Browsing about, I was led to the Wikipedia article on abortion which has a section about this. It reads:
Some purported risks of abortion are promoted primarily by anti-abortion groups, but lack scientific support. For example, the question of a link between induced abortion and breast cancer has been investigated extensively. Major medical and scientific bodies (including the World Health Organization, the US National Cancer Institute, the American Cancer Society, the Royal College of Obstetricians and Gynaecologists and the American Congress of Obstetricians and Gynecologists) have concluded that abortion does not cause breast cancer, although such a link continues to be promoted by anti-abortion groups.
The studies mentioned are all linked there. Since these names are really big ones, and they have concluded abortion does not further the risk of breast cancer, how come many Pro Lifers still make this claim? Is there any good reason? :shrug: