Condition Basics

What is emergency contraception?

Emergency contraception is a way to prevent pregnancy after unprotected vaginal sex. For example, you can use it if:

• You had sex without using birth control. There is a chance that you could get pregnant even if you haven't started having periods yet or you are getting close to menopause.
• Your birth control method failed. Maybe you forgot to take your pill or get your shot. Or maybe the condom broke or came off, or your diaphragm slipped.
• You used a birth control method that isn't very reliable, or you didn't use it the right way.
• You were sexually assaulted. Even if you were using birth control, emergency contraception can help decrease your chance of getting pregnant.

There are two types of emergency contraception: pills or an intrauterine device (IUD). Using emergency contraception right away can prevent an unwanted pregnancy. And it can keep you from worrying while you wait for your next period to start.

What are the types?

There are two main types of emergency contraception: pills and intrauterine devices (IUDs). Pills work well, don't cost a lot, and are usually easy to get. The IUD works very well, but it has to be inserted by a doctor.

• Pills used for emergency contraception are sometimes called "morning-after pills." They can be used up to 5 days after unprotected sex.
  • The most common option contains a progestin hormone called levonorgestrel. Progestin is a synthetic version of the hormone progesterone.
  • Another option is a medicine called ulipristal (for example, Ella). It affects the progesterone in your body.
  • Some birth control pills are also used. These often contain a combination of the hormones estrogen and progestin. If you already take birth control pills, you may be able to use the pills you have as emergency contraception. Talk to your doctor to find out the correct doses.
• An IUD is a small, T-shaped plastic device that is inserted into your uterus. It can be placed up to 5 days after unprotected sex to prevent pregnancy.
  • A copper IUD is a common option. Copper wire is wound around the stem of the T-shaped IUD. The copper IUD is approved by the U.S. Food and Drug Administration (FDA) to be used for up to 10 years. But studies show that extended use of the copper IUD safely prevents pregnancy for up to 12 years. Talk to your doctor about what might be right for you.
  • A hormonal IUD can also be used. This type releases levonorgestrel, which is a form of the hormone progestin. The hormonal IUD used for emergency contraception can prevent pregnancy for up to 8 years. Talk to your doctor about how long you can use it.

How does it work?

Emergency contraception pills work by preventing ovulation, fertilization, or implantation.

The hormones in these pills may prevent fertilization by stopping the ovary from releasing an egg (ovum). They also make the fallopian tubes less likely to move an egg toward the uterus. The pills are also thought to thin the lining of the uterus, or endometrium. The thickened endometrium is where a fertilized egg would normally implant and grow.

An IUD for emergency contraception may prevent fertilization or implantation.

Where can you get emergency contraception?

Where you get emergency contraception may depend on which type you use.

Emergency contraception pills

You can get emergency contraception pills without a prescription at most drugstores.

Some types of emergency contraception, such as ulipristal acetate (for example, Ella) are available only from family planning clinics or with a prescription from a doctor.

Birth control pills

If you already have birth control pills on hand, you may be able to use them for emergency birth control. To find out which brands of pills work and how to take them, go to www.plannedparenthood.org for emergency contraception information.

IUD

You can get an IUD from many doctors, from college and public health clinics, and in most hospital emergency rooms. An IUD has to be inserted by a doctor or other health professional.

What to do if you can't find emergency contraception

Some pharmacists won't sell emergency contraception or fill prescriptions for birth control pills. If this happens to you, ask for the location of a pharmacist who will, or go to or call the Planned Parenthood clinic nearest you.

How to Use It

How you use emergency contraception depends on which type you use.

Emergency contraception pills

The pills come in 1-pill or 2-pill packages. Follow the directions in the package, or take them as your doctor directs you to.

You can take emergency contraception up to 5 days after unprotected vaginal sex. But the sooner you take them, the more likely they are to prevent pregnancy.

Birth control pills as emergency contraception

For most regular birth control pills, you take one dose of 2 to 5 pills as soon as you can. Then you take a second dose 12 hours later. The dose depends on the type of pill.

If you use birth control pills for emergency contraception, keep these things in mind:

• Birth control pills can cause nausea. Take an antinausea medicine such as Dramamine with the first dose and again 1 hour before the second dose.
• If you vomit within 2 hours after you take the pills, call your doctor for advice. You may need to repeat the dose.
• Be sure you take the active hormone pills. In a 28-day pack, the first 21 pills contain hormones. The last 7 pills (the ones you take during your period) don't contain any hormones. If you use 21-day packs, all of the pills contain hormones.

Intrauterine device (IUD)

A doctor or other health professional has to insert an IUD.

How Well It Works

Overall, emergency contraception works well to prevent pregnancy.

An IUD is the most effective form of emergency contraception. It is inserted by a doctor and can almost always prevent pregnancy.

With emergency contraception pills, the sooner you take them the more likely they are to prevent pregnancy. A prescription pill with ulipristal acetate (such as Ella) works better in most cases to prevent pregnancy than the pill with levonorgestrel. Levonorgestrel pills may not be as effective. But they are available without a prescription at most drugstores.

If you are at a higher weight, emergency contraception pills may not work as well to prevent a pregnancy. Talk with your doctor about methods that aren't affected by your weight, such as an IUD.

Your doctor may suggest that you have a pregnancy test about 3 weeks after using emergency contraception.

Emergency contraception is not a replacement for regular birth control

Unless you get an IUD, emergency contraception doesn't take the place of regular birth control. Emergency contraception pills do not work as well as other regular types of birth control.

Emergency contraception pills won't protect you for the rest of your cycle. If you want to continue to prevent pregnancy, talk to your doctor about a birth control method to use regularly that will work for you. If you usually use a hormonal method of birth control, such as birth control pills, the vaginal ring, or the patch, check with your doctor about when to start using it again.

But accidents can happen. It is a good idea to keep a set of emergency contraception pills on hand in case you ever need it.

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Side Effects

Emergency contraception may cause some side effects.

• Emergency contraception pills can cause light bleeding (spotting). They can also cause your next period to start a few days earlier or later than you expect. Sometimes a headache, nausea, belly pain, dizziness, or fatigue can also happen.
• An intrauterine device (IUD) may cause cramping and bleeding during the first few days after it's inserted.

Call your doctor if you have side effects that don't get better.

If you're already pregnant:

• Emergency contraception pills should not harm the pregnancy.
• An IUD could cause problems with the pregnancy.