The morning-after pill is a type of emergency birth control that contains the hormone levonorgestrel, a progestin, (Plan B One-Step, Next Choice) or ulipristal acetate, a progesterone agonist-antagonist, (Ella).
The morning-after pill can be used after you've had unprotected sex. Depending on where you are in your menstrual cycle, the morning-after pill can prevent or delay ovulation, block fertilization, or keep a fertilized egg from implanting in the uterus. Don't take the morning-after pill if you're already pregnant.
Plan B One-Step, Next Choice and Ella are the only morning-after pills that have Food and Drug Administration (FDA) approval in the U.S. (Plan B, which consists of two pills, is being phased out by its manufacturer.) However, many other brands of morning-after pills are available around the world.
If you're age 17 or older, Plan B One-Step and Next Choice are available over-the-counter at most pharmacies. If you are age 16 or younger or want to use Ella, you'll need a prescription from your 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
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.
The morning-after pill isn't appropriate for everyone. Your health care provider may discourage use of the morning-after pill if:
The morning-after pill may be an option if you have diabetes. You may need to work with your health care provider to manage your blood sugar level after taking the morning-after pill, however.
Consult your health care provider if you're breast-feeding. While Plan B One-Step and Next Choice are safe to use during breast-feeding, use of Ella isn't recommended.
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 may include:
Side effects typically last only a few days.
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.
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. An estimated 1 to 2 out of 100 women who have unprotected sex one time and correctly use the morning-after pill will get pregnant. The morning-after pill doesn't offer protection from sexually transmitted infections.
How you prepare
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 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:
If you vomit within two hours after taking the morning-after pill, contact your health care provider to discuss whether to repeat the dose.
Last Updated: 2010-08-19
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