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In comments likely to stir controversy, Rep. Trent Franks, who has authored a measure banning all abortions after 20 weeks without exception, said the rate of pregnancies resulting from rape is "very low."

"The incidents of rape resulting in pregnancy are very low," Franks, R-Ariz., said during a Judiciary committee markup of his legislation today as he expressed his opposition to a Democratic amendment to allow exceptions for rape and incest.

"When you make that exception, there's usually a requirement to report the rape within 48 hours and, in this case, that's impossible because this is in the sixth month of gestation and that's what completely negates and vitiates the purpose of such an amendment."

It's unclear on what numbers Franks based his comments, but The Rape, Abuse & Incest National Network (RAINN) estimates that up to 5 percent of rape victims become pregnant.

Within hours of Franks' comments, the Democratic National Committee, Democratic Congressional Campaign Committee and an aide to House Minority Leader Nancy Pelosi each sent out email blasts capitalizing on news reports covering the Republican's remarks.

Franks' remarks harken back to the "legitimate rape" comments made last year by former Missouri Rep. Todd Akin, who failed in his bid for the Senate last fall after suggesting during a radio interview that a woman's body can shut itself down to prevent pregnancy.

Democrats believe a national 20-week abortion ban "represents a nationwide threat to the health and well-being of American women," a senior Democratic leadership aide said.

"I just find it astonishing to hear a phrase repeated that the incidence of pregnancy from rape is low," Rep. Zoe Lofgren, D-Calif., responded to Franks. "There's no scientific basis for that and the idea that the Republican men on this committee can tell the women of America that they have to carry to term the product of a rape is outrageous."

Franks' legislation later passed out of the Judiciary committee by a vote of 20-12 and is expected on the floor next week, a GOP leadership aide said.