Efficacy: 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 can reduce chance of pregnancy by up to 95% if used within 24 hours. 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.
Answered 11/19/2014
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A doctor has provided 1 answer
A doctor has provided 1 answer
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