Bachmann: ‘I have no idea’ if HPV vaccine causes mental retardation

Michele Bachmann is backing away from remarks she made on Monday suggesting that a vaccine that Rick Perry tried to make mandatory in Texas could cause "mental retardation." She said Tuesday she "had no idea" if that were true.

During Monday night's Republican presidential debate, Bachmann, a Republican representative from Minnesota, criticized Perry, the governor of Texas, for signing an executive order mandating that all girls entering the sixth grade in his state receive a vaccination for human papillomavirus (HPV), a sexually transmitted disease that can result in cervical cancer.

After the debate, the Minnesota congresswoman said she met a mother in the audience who told her that the drug had severe side effects for her daughter. "There's a woman who came up crying to me tonight after the debate," Bachmann said in an interview with Fox News. "She said her daughter was given that vaccine. She told me her daughter suffered mental retardation as a result of that vaccine."

When pressed by Sean Hannity the next day on his radio show her remarks--which she had just repeated on The Today Show earlier Tuesday morning--Bachmann said she didn't know if the drug could cause such side effects.

"I have no idea," Bachmann said, before repeating the story about the woman. "I am not a doctor. I am not a scientist. I am not a physician. All I was doing was reporting what a woman told me last night at the debate."

"The criticisms, congresswoman, is that there's no evidence that the vaccine causes mental retardation," Hannity replied.

The evidence backs up Hannity's skepticism. No such link has been proven, medical experts say.

"There is zero credible scientific evidence that vaccines cause mental retardation or autism," Evan Siegfried, a spokesman for the Global and Regional Asperger Syndrome Partnership told Politico's Ben Smith. "She should cease trying to foment fear in order to advance her political agenda."

The Center for Disease Control mentions no such side effects to the drug, listing only "fainting, pain, and swelling at the injection site."

Even on the right, Bachmann isn't finding many defenders. Talk radio host Rush Limbaugh echoed Hannity's skepticism, saying that Bachmann had "jumped the shark."

Ed Morrissey, a writer for Hot Air, one of the largest conservative blogs online, isn't buying it either. "It looks more like Bachmann sensed that she had won a point and wanted to go in for the kill, didn't bother to check the facts, and didn't care that she was stoking an anti-vaccination paranoid conspiracy theory, either," Morrissey wrote. "Neither shines a particularly favorable light on Bachmann."

The exchange between Bachmann and Hannity was first reported by Tom Scheck of Minnesota Public Radio.

Watch the latest developments from the NBC Today Show below.