The morning-after pill is a type of emergency birth control (contraception). The purpose of emergency contraception is to prevent pregnancy after a woman has had unprotected sex. Morning-after pills contain either levonorgestrel (Plan B One-Step, Next Choice) or ulipristal (Ella).
Plan B One-Step, Next Choice and Ella are the only morning-after pills that have Food and Drug Administration approval in the U.S. However, other brands of morning-after pills are available around the world.
Plan B One-Step is available over-the-counter without prescription. Next Choice is available over-the-counter for women age 17 and older. Ella is available only with a prescription from your doctor or health care provider.
Plan B One-Step
Plan B One-Step is a type of morning-after pill that can be used after unprotected sex to prevent pregnancy. Plan B One-Step contains the hormone levonorgestrel — a progestin — which can ...
Why it's done
Morning-after pills 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.
Morning-after pills can prevent pregnancy because 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 reach an egg. As a result, using emergency contraception soon after unprotected sex isn't too late to prevent pregnancy.
Morning-after pills do not end a pregnancy that has implanted. Depending on where you are in your menstrual cycle, morning-after pills may act by one or more of the following actions: delaying or preventing ovulation, blocking fertilization, or keeping a fertilized egg from implanting in the uterus. However, recent evidence strongly suggests that Plan B One-Step and Next Choice do not inhibit implantation. It's not clear if the same is true for Ella.
Keep in mind that the morning-after pill isn't the same as mifepristone (Mifeprex), also known as RU-486 or the abortion pill. Mifeprex terminates an established pregnancy — one in which the fertilized egg has attached to the uterine wall and has already begun to develop.
Emergency contraception is an effective option for preventing pregnancy after unprotected sex, but it isn't as effective as other methods of contraception and isn't recommended for routine use. The morning-after pill also doesn't offer protection from sexually transmitted infections.
An estimated 1 to 2 women will become pregnant out of 100 women who have unprotected sex one time and correctly use the morning-after pill.
The morning-after pill isn't appropriate for everyone. Tell your health care provider if:
In addition, make sure you're not pregnant before using Ella. The effects of Ella on a developing baby are unknown. However, if you're already pregnant when you take Plan B One-Step or Next Choice, the treatment will simply be ineffective and won't harm the developing baby.
Side effects of the morning-after pill typically last only a few days and may include:
How you prepare
For maximum effectiveness, emergency contraception should be started as soon as possible after unprotected intercourse, and within 120 hours. You can take emergency contraceptive pills anytime during your menstrual cycle.
If you're age 17 or older, Plan B One-Step and Next Choice are available over-the-counter at most pharmacies. If you're age 16 or younger or you want to use Ella, you'll need a prescription from your health care provider. Some health care providers may provide an advance prescription for emergency contraception, just in case.
Remember to talk to your health care provider about any other medications you're taking.
What you can expect
To use the morning-after pill:
Using the morning-after pill may delay your period by up to one week. If your period is more than one week late, take a pregnancy test.
If you have bleeding or spotting that lasts longer than a week or develop severe lower abdominal pain three to five weeks after taking the morning-after pill, contact your health care provider. These may be signs or symptoms of a miscarriage or an ectopic pregnancy — when the fertilized egg implants outside the uterus, usually in a fallopian tube.
Last Updated: 2013-06-28
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