A European manufacturer of an emergency contraceptive pill identical in chemical composition to Plan-B One Step and other generic brands has issued an alarming warning about the effectiveness of the morning-after pill in women who weigh more than 165 pounds.

According to HRA Pharma, the French manufacturer of the emergency contraceptive Norlevo, the drug begins to lose its effectiveness for women who weigh more than 165 pounds and is completely ineffective for women who weigh more than 176 pounds. European pharmaceutical regulators have updated the packaging of the drug to reflect the weight limits.

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Norlevo is sold throughout Europe, Australia, parts of China and Africa and elsewhere in the world, but this news, if true, also has major implications for women who take emergency contraceptive pills identical in chemical makeup and dosage to Norlevo in the United States.

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