By DR. SWATI SHROFF and DR. TIFFANY CHAO, ABC News Medical Unit

Missouri Representative Todd Akin contradicted medical statistics with his statement that "women who are victims of 'legitimate rape' rarely get pregnant."

After a media storm - during which Mitt Romney called his words "indefensible" and President Obama said "rape is rape" - Akin has now released an ad in which he admits, "The fact is, rape can lead to pregnancy."

There are also numerous studies regarding rape and pregnancy. Some data show that rape can not only result in pregnancy, but it may even lead to higher rates of pregnancy than consensual sex.

The Rape, Abuse & Incest National Network (RAINN) reports someone in the United States is sexually assaulted every two minutes, and on average there are 207,754 victims (age 12 or older) of sexual assault every year.

How many become pregnant? A 1996 study in the American Journal of Obstetrics and Gynecology reported that "among adult women an estimated 32,101 pregnancies result from rape each year." This study said the rate of becoming pregnant after sexual assault is considerable, estimating that "the national rape-pregnancy rate is 5.0 percent per rape among victims of reproductive age (aged 12 to 45)."

In response to Akin's comments, the American Congress of Obstetricians and Gynecologists (ACOG) released a statement on Monday: "Each year in the U.S., 10,000-15,000 abortions occur among women whose pregnancies are a result of reported rape or incest."

The statement said this is a fraction of the total number of rape-pregnancies, given that "an unknown number of pregnancies resulting from rape are carried to term."

A 2003 study using data from the United States National Violence Against Women survey found that the rate at which women get pregnant after an incident of sexual assault is more than double that of a single act of consensual sex. In this report, published in the journal Human Nature, the per-incident rape-pregnancy rate was 6.42 percent, and as high as 7.98 percent with statistical correction. Of women having consensual sex, the per-incident pregnancy rate was 3.1 percent.

Dr. Lauren Streicher, an assistant professor at the Feinberg School of Medicine at Northwestern University in Chicago, said she was not surprised by the data.

"Women that have consensual sex are usually aware of where they are in a cycle…part of consensual sex is being able to say no. It makes sense," she said.

In response to Akin's statement that "If it's a legitimate rape, the female body has ways to shut that whole thing down," Streicher said, "You let me know if you find the doctor that knows how a uterus knows which sperm to ward off."

In its statement, ACOG refuted Akin's original comment: "To suggest otherwise contradicts basic biological truths."