Respuesta :

at least 72 hours after
Hello!

Levonogestrel pills, including the brands Plan B One-Step and Next Choice One Dose, are up to 89 percent effective when taken within 72 hours (three days) after unprotected sex. They continue to reduce the risk of pregnancy up to 120 hours (five days) after unprotected sex, but they are less effective as time passes.

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