They are abortifacients. Like other methods of abortion, they end the life of a developing child in the womb. In some cases, the way in which a device or drug works which is intended as a contraceptive has been a mystery. There is still debate in the medical community over exactly how contraceptive pills work and whether they are truly contraceptive or instead act to prevent the fertilized ovum from implanting in the wall of the uterus. One prominent newspaper account described the effect of the drug as preventing fertilization.
Advocates often tout the drug as a method of reducing abortions.
Obstetrician and gynecologist Dr. William J. Hogan writes, When a woman's egg is fertilized in the fallopian tube, she is pregnant. Five to seven days after fertilization, the new human being arrives in the cavity of the uterus and implants there. Therefore, it does not reduce the number of abortions but increases it. Contraceptives are used in preparation for intercourse in an effort to prevent union of sperm with egg.