Pubmed puts the smackdown on that particular claim:

The national rape-related pregnancy rate is 5.0% per rape among victims of reproductive age (aged 12 to 45); among adult women an estimated 32,101 pregnancies result from rape each year. Among 34 cases of rape-related pregnancy, the majority occurred among adolescents and resulted from assault by a known, often related perpetrator. Only 11.7% of these victims received immediate medical attention after the assault, and 47.1% received no medical attention related to the rape. A total 32.4% of these victims did not discover they were pregnant until they had already entered the second trimester; 32.2% opted to keep the infant whereas 50% underwent abortion and 5.9% placed the infant for adoption; an additional 11.8% had spontaneous abortion.

Pregnancy from consensual sex comes in at about 2.5% to 3.1% per act of intercourse.

Akin’s ideas did not arise in isolation - websites like Christian health resources make this claim, as do various other anti-abortion websites in the US.

The claim is one that is associated with the Middle Ages – when it was used to argue that because the woman got pregnant, it wasn’t really rape. The sheer evil of that is staggering, and part of the importance Akin using the word “legitimate”.

I shudder to think of what this sort of thinking means on juries of rape trials.

It is also important because for a lot of other debates in US politics, children appear to be viewed as being purely the responsibility of their parents.

The right to life argument, for a lot of pro-life campaigners, ends once the child is out of the womb. Once the child is out the womb, the child is no longer the state’s problem according to a lot of US conservative arguments.

Due to the same wing of the Republican Party that is most actively “pro-life”, tying up the US congress’ funding debates – the children of US military personnel are at risk of getting a worse education.

The schools on US military bases don’t get funding from property taxes, they are funded by the government as a whole so when the US goes for an austerity budget, it means those schools end up dropping subjects.

Once the child is born – in conservative parlance there is no real consideration of that child’s welfare, it becomes an issue of “personal responsibility” and single mothers “should have abstained from sex” if they didn’t want children.

So those military kids aren't the government's responsibility under this sort of thinking, they are the responsibility of their parents.

Even if you accept that line of reasoning, which I don’t because I think it reduces children to punishments for “loose” behaviour, the existence of children by rape robs it of any moral force.

The politics of ‘personal responsibility’ require personal choice – and where that is not present you get a clear view of exactly how shallow and callous those arguments really are.

It is not simply about what rape means for the abortion argument, but what rape means for the public spending debate as a whole.

The basic assumption of choice at the heart of a lot of conservative arguments; is a dangerous mentality in a legislator and it is unfortunate how common it is.