LONDON (AP) -- A commonly used morning-after pill is suitable for use by heavier women, the European Medicines Agency said Thursday after a review of the evidence sparked by the French manufacturer's declaration that the drugs didn't work in women weighing more than 80 kilograms (176 pounds).
Last November, HRA Pharma changed the labels on its morning-after pill Norlevo, marketed in 50 countries, saying it was ineffective in women over 80 kilograms after a study of levonorgestrel, one of the drug's active ingredients. Norlevo is not sold in the U.S. but another drug with the same main ingredient, Plan B One-Step, is widely available. The Food and Drug Administration said last year it was reviewing the issue to see if any label changes were needed.
In a statement on Thursday, the EMA said it had assessed all the available evidence and announced the data "are too limited and not robust enough to conclude with certainty" that the pill's efficacy is reduced in heavier women. It said the results of these studies should be included in the product information but that current warnings on Norlevo's packaging should be deleted.
The morning-after pill contains a higher dose of the hormone in regular birth control pills. Taking it within 72 hours of sexual intercourse can cut the chances of pregnancy by up to 89 percent but it works best within the first 24 hours. If a woman is already pregnant, the pill, which prevents ovulation or fertilization, has no effect.
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