Emergency Birth Control: Teen Version

What is emergency birth control used for?

Emergency birth control can prevent pregnancy if it is used very soon after you had unprotected sex. If you are already pregnant, emergency birth control will NOT stop the pregnancy. You may decide that you need emergency birth control if:

  • You had sex without using any birth control.
  • Your regular birth control method failed while you were having sex. For example, a condom broke or slipped off.
  • You had sex after missing 2 or more birth control pills in a row.
  • You were forced to have sex without protection (rape).

How does it work?

The 2 main forms of emergency birth control are:

  • Emergency birth control pills (ECP)
  • Copper IUD (intrauterine device)

Emergency birth control pills are also called morning-after pills and several brands are available. The pills contain female hormones. They may work in several ways to prevent pregnancy, such as:

  • Stopping the release of an egg from the ovary
  • Stopping fertilization (when the sperm joins with the egg)
  • Thickening the mucus of the cervix, making it hard for sperm to reach the egg
  • Keeping a fertilized egg from attaching to the womb

Emergency birth control pills should be taken as soon as possible after unprotected sex. Depending on the type of medicine in the pills, the pills need to be taken no later than 72 to 120 hours (3 to 5 days) after sex.

Most women do not get pregnant if they take the pills within 3 days after sex. The effectiveness is highest (98%) if the pills are taken within 12 hours after sex. This means that no more than 2 women of every 100 get pregnant after taking the pills.

A copper intrauterine device (IUD) may be put into the uterus after unprotected sex. It may prevent pregnancy by:

  • Stopping fertilization
  • Keeping a fertilized egg from attaching to the womb

A copper IUD is over 99% effective if the IUD is inserted within 5 days of unprotected sex. The IUD may then be left in the uterus as a regular method of birth control.

With either method of emergency birth control, you will usually have your next menstrual period at the expected time or within a week of the expected time.

What else do I need to know about this medicine?

  • You can buy some types of emergency birth control pills without a prescription. Carefully follow the package instructions or your healthcare provider’s directions for taking the pills.
  • This medicine does not keep you from getting AIDS or other sexually transmitted infections. Latex or polyurethane condoms are the only method of birth control that can protect against the HIV virus and AIDS.
  • Emergency birth control pills cannot be used as a regular birth control method. They are meant for infrequent emergency protection. They do not work as well as correct use of most other forms of birth control. If you need to use emergency birth control often, you should ask your healthcare provider about the best methods of birth control and prevention of sexually transmitted infections.
  • Follow the directions that come with your medicine, including information about food or alcohol. Make sure you know how and when to take your medicine. Do not take more or less than you are supposed to take. If you have unprotected sex again after taking the pills, the pills you took will not keep you from getting pregnant.
  • Many medicines have side effects. A side effect is a symptom or problem that is caused by the medicine. Ask your healthcare provider or pharmacist what side effects the medicine may cause and what you should do if you have side effects.
  • Try to get all of your prescriptions filled at the same place. Your pharmacist can help make sure that all of your medicines are safe to take together.
  • Keep a list of your medicines with you. List all of the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Tell all healthcare providers who treat you about all of the products you are taking.

If you have any questions, ask your healthcare provider or pharmacist for more information. Be sure to keep all appointments for provider visits or tests.

Developed by RelayHealth.
Pediatric Advisor 2015.1 published by RelayHealth.
Last modified: 2014-02-07
Last reviewed: 2014-02-05
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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