The move is the latest chapter in a 10-year, controversial debate about who should have access to the drug and why.
Plan B prevents implantation of a fertilized egg in a woman's uterus through use of levonorgestrel, a synthetic form of the hormone progesterone used for decades in birth control pills. Plan B contains 1.5 milligrams of levonorgestrel, more than "the Pill" contains. It is considered a form of birth control, not abortion.
Women's health advocates praised the FDA decision.
"While there are still practical questions to resolve, this is an important step forward to expand access to emergency contraception and for preventing unintended pregnancy," Cecile Richards, president of Planned Parenthood Federation of America, said in a news release.
"Emergency contraception is a safe and effective form of birth control that can prevent pregnancy if taken within five days of unprotected sex," she added. "This decision will eliminate some of the biggest barriers and hurdles that women face in getting emergency contraception when they need it, which means many more women will be able to prevent unintended pregnancy."
But not everyone is likely to be pleased with the move.
Earlier this month, Janice Shaw Crouse -- director and senior fellow at the Beverly LaHaye Institute, the think tank for the conservative women's group Concerned Women for America -- called Korman's ruling "a political decision, made by those who stand to profit financially from an action that puts ideology ahead of the nation's girls and young women."
"It is irresponsible to advocate over-the-counter use of these high-potency drugs, which would make them available to anyone -- including those predators who exploit young girls," Shaw Crouse said.
In his ruling, Korman was dismissive of the government's arguments and, in particular, previous decisions by U.S. Health and Human Services Secr
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