E-Bay Medical Licenses

Today's big political news was Missouri Republican Senate candidate Todd Akin's theory that women can't be impregnated (except very rarely) through rape.

I wonder how this is supposed to work. Does the egg somehow know that the sperms are released during a rape and then kick them out because it doesn't want to be fertilized because of that, or does a woman that are forced to have sex sends out some signal from her brain that activates some barrier that prevents sperms from reaching her eggs?

Anyway, what we do know for sure is that his theory is laughably false. He claims that he heard this from doctors. That leaves two options: either he is lying about that, or they do in fact sell medical licenses on E-bay....