Emergency contraception is birth control that prevents pregnancy after sex, which is why it is sometimes called "the morning after pill," "the day after pill," or "morning after contraception." You can use emergency contraception right away - or up to five days after sex - if you think your birth control failed, you didn't use contraception, or you were forced to have sex.
Emergency contraception makes it much less likely you will get pregnant. But emergency contraceptives are not as effective as birth control that's used before or during sex, like the pill or condoms. So if you are sexually active or planning to be, don't use emergency contraception as your only protection against pregnancy. Also, emergency contraception does not protect against sexually transmitted infections, like HIV (only condoms do). - Slides
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