Trusted medical advice from the
American Academy of Family Physicians.

Emergency Contraception

Emergency contraception is a form of birth control. It can help prevent pregnancy if used within 5 days of having unprotected sex. If you are pregnant, emergency contraception pills will not stop or harm your pregnancy.

Emergency contraception is used in certain situations, including:

  • You had unprotected sex.
  • You had unprotected sex and forgot to take your birth control pills.
  • Your partner’s condom broke or slipped off during sex.
  • Your diaphragm or sponge came out of place during sex.
  • You were raped.

Types of emergency contraception

There are 2 types of emergency contraception available. One option is medicine, which is often known as “the morning-after pill.” In the United States, pills that contain levonorgestrel (Plan B One-Step®) do not require a prescription from your doctor. You can purchase them over the counter at a pharmacy. Pills that contain ulipristal acetate (ella®) do require a prescription.

The second option is to use an intrauterine device (IUD) that contains copper (ParaGard). You must go to a doctor to have an IUD inserted.

Emergency contraceptive pills can be very effective if they are used in time. The pills are most effective when taken within 24 hours of having sex. They are still effective when taken up to five days after having sex. Ulipristal acetate pills reduce your risk of pregnancy more than levonorgestrel pills. The pills cannot prevent pregnancy if you have unprotected sex after taking them.

ParaGard, an IUD, is a small, T-shaped device that is placed inside your uterus. Unlike pills, IUDs don’t stop your ovaries from releasing an egg. They can prevent an egg from being fertilized or implanted. An IUD is very effective for emergency contraception. It can reduce your risk of pregnancy by more than 99%. This is true if your doctor inserts it within 5 days of sex. This IUD can be left in your body for up to 10 years to prevent pregnancy. Some women use IUDs as their regular form of birth control. Common side effects of a ParaGard IUD are heavier, longer periods and spotting or cramping between periods. Symptoms usually improve in the first 3 to 6 months.

Where to get emergency contraception

Places to get emergency contraception include:

  • Your primary care doctor’s office.
  • College/university and women’s health centers.
  • Public health departments.
  • Hospital emergency departments.
  • Planned Parenthood centers.

Path to improved health

Emergency contraception can prevent pregnancy by:

  • Stopping ovulation (the release of an egg from your ovaries).
  • Stopping sperm from fertilizing an egg.
  • Stopping a fertilized egg from implantation (attaching itself to the wall of your uterus).

Emergency contraception cannot prevent or end pregnancy if a fertilized egg already is implanted. Because of this, emergency contraception is not a means of abortion.

Most medicine brands require a single dose of 1 pill. Some brands have 2 doses (1 pill followed by a second pill 12 hours later). Sometimes, you can take both pills together. Follow the instructions for each specific brand. The U.S. Food and Drug Administration (FDA) says that some brands of regular birth control pills can be used in increased doses for emergency contraception. However, this method is less effective. It can cause more side effects. Talk to your doctor to see if your birth control pills are safe for emergency use.

Some women feel nauseous after they take emergency contraceptive pills. This feeling should go away in about 2 days. Your doctor can give you medicine to reduce nausea. Other possible side effects include:

  • headache
  • cramping
  • tender breasts

Things to consider

Keep in mind, emergency contraception does not protect against sexually transmitted diseases (STDs). You should not use any emergency contraception if you know you are pregnant or are trying to get pregnant.

Women who are breastfeeding should not use pills that contain ulipristal acetate. Pills also are less effective for women who are overweight or have obesity. Instead, these women should use the ParaGard IUD. Do not get an IUD if you:

  • Have abnormal bleeding.
  • Have cancer of the cervix or uterus.
  • Have the AIDS infection.
  • Are allergic to copper.

Emergency contraceptive pills can affect your menstrual cycle. Talk to your doctor if you do not get your period within 1 month after taking them. Your doctor also can tell you when to start taking your regular form of birth control again. It will vary if you use a hormonal form, such as pills, shots, the patch, or a vaginal ring. If you use a barrier method, such as a diaphragm or condoms, you can start using it right away. If you do not use birth control, talk to your doctor about which method will work best for you.

Questions to ask your doctor

  • Which type of emergency contraceptive pills should I use?
  • What happens if I take extra regular birth control pills in an emergency?
  • How soon after unprotected sex should I take a pregnancy test?
  • Will emergency contraception cause an abortion?
  • Can I use emergency contraception even if I can’t normally tolerate birth control pills?

Resources

National Institutes of Health, MedlinePlus: Emergency contraception

U.S. Department of Health and Human Services, Office on Women’s Health: Emergency Contraception

 

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