Emergency contraception (Plan B) is most effective if taken within how many hours after unprotected intercourse?

Emergency contraception (Plan B) is most effective if taken within how many hours after unprotected intercourse?

• A. Within 72 hours after unprotected intercourse.
• B. Within 24 hours after unprotected intercourse.
• C. Within 96 hours after unprotected intercourse.
• D. Within 48 hours after unprotected intercourse.

Answer: (A)

Emergency contraception with Plan B works best when taken as soon as possible after unprotected intercourse because its effect hinges on preventing ovulation or fertilization. The effectiveness window for levonorgestrel-based emergency contraception is within 72 hours after intercourse, with protection strongest the earlier you take it. While taking it within 24 hours offers the highest chance of preventing pregnancy, the option set shows 72 hours as the latest time still considered effective. Beyond 72 hours, the likelihood of preventing pregnancy drops considerably, making a 96-hour window not appropriate for this method.

Emergency contraception with Plan B works best when taken as soon as possible after unprotected intercourse because its effect hinges on preventing ovulation or fertilization. The effectiveness window for levonorgestrel-based emergency contraception is within 72 hours after intercourse, with protection strongest the earlier you take it. While taking it within 24 hours offers the highest chance of preventing pregnancy, the option set shows 72 hours as the latest time still considered effective. Beyond 72 hours, the likelihood of preventing pregnancy drops considerably, making a 96-hour window not appropriate for this method.