How effective is Plan B?

The morning-after pill Plan B is most effective (>97%) when taken within 24 hours of unprotected sex and 75%-89% effective if you take it within three days.
Taking Plan B at the appropriate time after unprotected intercourse can help prevent unwanted pregnancies.

Is it time for Plan B?

Plan B Emergency Contraception, NYS Approved OB/GYN, Brooklyn, NYC

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Plan B might be less effective for women over a certain weight, but it's not worthless.

Emergency Contraceptives National Center for Health Research