How Plan B works

Pharyngula has a nice, simple explanation of how Plan B emergency contraception works, and how it can't remotely be construed as a form of abortion (unlike the use of RU-486, which is an abortifacient). The use of Plan B prevents ovulation--it doesn't do anything to an already fertilized egg. It thereby prevents the need for abortions when it's used effectively. Yet this timeline of events shows how the Republicans have been preventing it from being made available as an over-the-counter medicine.