Learning About Emergency Contraception Pills

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What is emergency contraception?

Emergency contraception is used to prevent pregnancy. You can use it if you were raped or you had unprotected sex. Or you can use it if you think your birth control didn't work. For example, you may use it if a condom breaks.

If you had sex without birth control, you could get pregnant. This is true even if you have not started your periods yet or are close to menopause.

If you use emergency contraception right away, it can prevent an unwanted pregnancy. It can also keep you from worrying while you wait for your next period.

Do not use emergency contraception pills as your only form of birth control. They do not work as well as other types of birth control. Talk to your doctor about the best kind of regular birth control for you.

How well does it work?

Progestin-only emergency contraception pills, such as Plan B or Next Choice, prevent about 74% of expected pregnancies. This means that out of 100 women who may expect to get pregnant, 74 did not.

If you weigh 75 to 80 kg, emergency contraceptive pills may not work as well to prevent a pregnancy. Emergency contraceptive pills will not prevent a pregnancy in women who weigh over 80 kg. Talk with your doctor about methods of emergency contraception that aren't affected by a woman's weight, such as the copper IUD.

NOTE: This information focuses on using progestin-only pills that are packaged specially for use as emergency contraception. These are often called "morning-after pills." Regular birth control pills or a copper IUD can also be used as emergency contraception. But they are not covered in this information.

How do you use emergency contraception pills?

  • Always follow the directions in the package. In general:
    • The pills come in 1-pill or 2-pill packages. If you choose the package with 2 pills, you can take both pills at the same time. Or you can take 1 pill right away and the second pill 12 hours later.
    • You can use these pills up to 5 days after unprotected sex. But it works best if you take them right away or within 48 hours.
    • The pills won't protect you for the rest of your cycle. Use your regular method of birth control. Or use condoms until you have a period.

What else do you need to know?

  • If you are already pregnant, emergency contraception pills won't hurt the baby.
  • After you use the pills, your next period may be early or late. If your next period does not start within 3 weeks, call your doctor or nurse call line for a pregnancy test. Or you can take a home pregnancy test.
  • The pills do not protect you from sexually transmitted infections (STIs), such as herpes or HIV/AIDS.
  • The pills may cause spotting or mild side effects like those of birth control pills. They usually don't cause nausea. Call your doctor or nurse call line if you have a headache, feel dizzy, or have belly pain that is severe or that lasts longer than 1 week.
  • You can get emergency contraception without a prescription at most drugstores.

Where can you learn more?

Go to https://www.healthwise.net/patientEd

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