After a sperm fertilizes an egg, cells divide in a stage called a blastocyst. Doctors say pregnancy doesn't start until the blastocyst implants into the woman's uterus. iStockphoto.com hide caption

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House Speaker John Boehner speaks to the media Wednesday after meeting with the president about the debt limit. "We know what the problems are — let's not kick the can down the road one more time," he said. Saul Loeb/AFP/Getty Images hide caption

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Former Alaska Gov. Sarah Palin, center, visits a Civil War-era cemetery, Tuesday, May 31, 2011, at Gettysburg National Military Park. Timothy Jacobsen/AP hide caption

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Asma Jehangir, a human rights advocate and lawyer in Lahore, Pakistan, is an outspoken critic of the military. Jim Wildman/NPR hide caption

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