As a guy with some experience prosecuting sexual assault cases, let me just say that anyone who thinks every allegation of rape is true is an idiot. Of course we know seabeyond is an idiot, but whatever. The majority of the claims are legitimate, of course, and initially all victims, of any crime, are entitled to have their complaint heard with compassion and the presumption they are telling the truth. Many, many times, though, there turns out to be a lot more to the story and an ulterior motive involved, like the victim making the claim to cover up for some misdeed of her own, advantage in an on-going dispute like custody, or even revenge.
Probably one of the things in the back of Akin's mind, which it would have been much better to just shut up about entirely, was the fact that if rape and incest were the only reasons an abortion could be had, there would naturally be a big increase in claims of rape with 'unknown perps' by 'victims' who decline decline to cooperate beyond getting the abortion (As well as a certain small number of alleged perps who are actually innocent and end up wrongly convicted), and then clam up and won't testify once the abortion is out of the way. This requirement, after all, adds a motive to lie for people who want a voluntary abortion, and yes, a lot of people are that low. But, trying to parse fake claims of rape from real claims of forcible or duress rape is a distinction that can't possibly survive the media spin machine, and it was incredibly foolhardy to even try to go down that road in public comments.