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Why it's doneBy Mayo Clinic staff
It's always a good idea to make a decision about birth control before having sex. However, the morning-after pill can help prevent pregnancy if you've had unprotected sex — whether you didn't use birth control, you missed a birth control pill or your method of birth control failed.
Conception typically doesn't occur immediately after sex. Instead, it may happen up to several days later. During the time between sex and conception, sperm travel through the fallopian tubes until they potentially meet up with an egg. As a result, taking emergency birth control soon after unprotected sex isn't too late to prevent pregnancy.
It's safe to use the morning-after pill during breast-feeding.
Keep in mind that the morning-after pill isn't the same as mifepristone (Mifeprex), also known as RU-486 or the abortion pill. The morning-after pill can prevent pregnancy. If you're already pregnant when you take the morning-after pill, the treatment will be ineffective and won't harm the developing baby. The abortion pill terminates an established pregnancy — one in which the fertilized egg has attached to the uterine wall and has already begun to develop.
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