Todd Akin's most recently unearthed gaffe - the statement, from a 2008 speech, that doctors "give abortions to women who are not actually pregnant" - has caused widespread puzzlement.

Here's the quote:

You find that along with the culture of death go all kinds of other law-breaking: Not following good sanitary procedure, giving abortions to women who are not actually pregnant, cheating on taxes, all these kinds of things.

Seems like a bit of a tricky thing for a doctor to do. Almost impossible, in fact. But Akin isn't alone in having this thought. Amongst anti-choice activists, it's a fairly widespread "fact".

According to a testimonial by Carol Everett, a clinic worker turned strident anti-choice activist, the phenomenon happens regularly:

There are two other things I'd like to talk about. There are women who come in and have abortions but aren't pregnant. You may say, "Oh, that doesn't happen." Maybe you say that. It does happen. First of all, this woman thinks she's pregnant. She's scheduled herself for an abortion. She's come in and her pregnancy test is negative. They have a woman that they have paid their advertising dollars to get in there. They want to do that abortion if there is any way.

So they do everything they can to prove that she's pregnant or has been pregnant. You say "has been pregnant?" Yes, if they can convince her that she has been pregnant, that she's had a spontaneous abortion. She's going to have to go into the hospital to have a D&C to remove the rest of the contents of her uterus. They will convince her to go ahead and have a procedure she doesn't need that day. And it happens. Channel four [Dallas-FortWorth] got it on tape -- a woman that went directly from our office to a doctor's office and the doctor told her that she was and had never been pregnant, and we had tried to do an abortion on her. I don't know what percentage that is. I have no idea...

Her story has been vigorously denied by former colleagues, but the trope is a common one in anti-abortion campaigning. Here's Wendy Wright of Concerned Women for America in support of an anti-abortion bill in Ohio:

Would abortionists do abortions on women who are not pregnant? Numerous reports from investigative journalists, state inspectors, and abortion providers have revealed abortionists who routinely committed abortions on Women who were not pregnant.

There's no firm evidence for the practice, and it's an odd thing for anti-abortionists to flag up (as there's no potential child involved). But it does play into more general ideas of women as victims of abortion and doctors as keen advocates. It's not just a gaffe this time - it's a recurring theory.