IUD use attracts new opposition from anti-abortion groups https://t.co/JPfoN4NYOr pic.twitter.com/HCnNOpR9I3

— Reuters Legal (@ReutersLegal) December 1, 2015

A rapid increase in the number of U.S. women turning to intra-uterine devices to prevent pregnancy has prompted escalating attacks on the birth control method from groups that oppose abortion.

The next battle will be at the U.S. Supreme Court, which has agreed to consider a new religious challenge to contraceptives coverage under President Barack Obama’s healthcare law. Although the case deals broadly with whether religiously affiliated groups should be exempt from providing birth control coverage to their employees, some parties in the case have focused specifically on IUDs.

IUDs work primarily by preventing sperm from reaching an egg. But they have come under fire from anti-abortion groups because, in rare instances, they can prevent a fertilized egg from implanting in the uterus. Those who believe that life begins at conception consider blocking implantation to be terminating a pregnancy rather than preventing pregnancy.

“IUDs are a life-ending device,” said Mailee Smith, staff counsel for the Americans United for Life, which filed an amicus brief in support of the challenge before the high court. “The focus of these cases is that requiring any life-ending drug is in violation of the Religious Freedom Act.”

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