The morning-after pill may not work for you if you weigh more than 165 pounds—and that's distressing news, considering the average American woman weighs more than that. HRA Pharma, the French manufacturer of an emergency contraceptive called Norlevo, is set to start warning women that the pill starts becoming less effective at that weight, and loses its effectiveness entirely in women who weigh more than 176 pounds. Norlevo is identical in dosage and chemical makeup to some of the most popular morning-after pills in the US, including Plan B, Mother Jones reports.
Norlevo, Plan B, and other similar over-the-counter pills use levonorgestrel, and are the best emergency contraceptives you can get without a prescription. And while Norlevo will see its packaging changed to reflect the new information, so far no changes are planned to packaging for any of the US pills. It's not yet clear whether a levonorgestrel pill can be adjusted to work in women with higher body mass indexes, and an HRA Pharma rep recommends heavier women "discuss alternative emergency contraceptive options with their physician: IUD or alternative oral emergency contraceptive." For your reference, an IUD can cost as much as $900 to have inserted.