Emergency Contraception (EC) – Center for Young Women's Health

Emergency contraception (EC) is a backup method of birth control for preventing pregnancy after unprotected PIV (penis-in-vagina) sex. Even though it’s commonly called the “morning-after pill,” EC includes both pills and an intrauterine device (IUD) that can actually be used within 5 days (120 hours) of unprotected intercourse. The sooner you take the medication or insert an IUD, the more likely they will prevent pregnancy.

When should a person use emergency contraception?

Emergency contraception (EC) should be used if:

You had unprotected PIV sex, which means your partner did not use a condom and you are not using another method of birth control (pill, IUD, Nexplanon arm implant, etc).
You forgot to take your birth control pills on time (and you’ve been having PIV sex).
You forgot to change or insert your hormonal ring, or apply your birth control patch (and you’ve been having PIV sex).
Your partner’s condom broke or slipped off while you were having sex.
You were forced to have unprotected intercourse (rape).

How does emergency contraception work?

EC medications work by giving a short, strong burst of hormones that changes your menstrual cycle and prevents ovulation (the time in your cycle when you are most likely to become pregnant). The copper and hormonal IUDs work by preventing fertilization of the egg. If left in the uterus, a copper IUD will continue to protect against pregnancy for up to 10 years or until removed by a health care provider.

It’s important to remember that EC doesn’t continue to protect against pregnancy during the rest of the menstrual cycle. You should always try to use birth control when having sex. If you have a uterus and are planning to or currently having penetrative sex with a person with a penis, make a plan to get on birth control if you would like to avoid an unintended pregnancy. Talk to your provider about which option is best for you! Remember to always use a condom for added protection against pregnancy and sexually transmitted illnesses.

Does emergency contraception (EC) cause an abortion?

No. Emergency contraception (EC) does not work if a person is already pregnant. EC will NOT cause an abortion.

Names of EC you should be familiar with:

Levonorgestrel (1.5mg pills) Plan B One-Step®,Next Choice One Dose®, MyWay®, AfterPill™. These are available over-the-counter without a prescription. The directions say to use medication within 3 days (72 hours) but it has been shown to be effective up to 5 days after unprotected PIV intercourse. However, EC is most effective when taken as early as possible.
Ulipristal acetate (30mg) includes Ella™ (ulipristal acetate or UPA). This is one pill (one dose) that can be taken up to 5 days or 120 hours after unprotected PIV intercourse. A prescription is often needed for this pill, but in some states a pharmacist can dispense Ella™ without a prescription. Ella™ may also be purchased online after a telephone consultation; however, it is likely to be more expensive and you may need to factor in overnight shipping. Please be aware that online pharmacies cannot mail Ella™ to certain states, including Arkansas, Missouri, North Carolina, and Oregon. Your health care provider can write you an “advanced prescription” for Ella™ so it will be available for you if you have unprotected sex in the future. Talk to your provider about this option.
Copper Intrauterine Device: ParaGard®. This IUD is a small copper device placed in your uterus (through your vagina). It can be used to prevent pregnancy after unprotected PIV sex and future pregnancies for up to 10 years as long as it remains in place. IUDs are the most effective of all EC options. The copper IUD can be inserted in a person’s uterus at most family planning clinics. If the person has no signs of vaginal or uterine infection, the IUD can be inserted right away.
Other Oral Contraceptive Pills. Some oral contraceptive pills may be prescribed in two high doses (12 hours apart) by a health care provider. This type of EC must be taken within 72 hours of unprotected PIV intercourse. However, this form of EC is the least effective, and can cause nausea and vomiting.
Mirena® Hormonal Intrauterine Device (52 mg levonorgestrel). The Mirena IUD appears to be an effective option for EC. When placed in your uterus (through your vagina), this hormonal IUD may prevent pregnancy after unprotected PIV sex and future pregnancies for up to 8 years.

How effective is emergency contraception?

It’s important to remember that EC doesn’t guarantee that pregnancy will be prevented. The risk of pregnancy depends on the type of EC used, when in your menstrual cycle you had sex, and what kind of birth control you use. You’re more likely to get pregnant around the time when the ovary releases an egg (ovulation). The pregnancy rate is less than 2% after ulipristal acetate use, 2-2.5% with levonorgestrel (Plan B), and 0-2% after IUD insertion.

Weight has been shown to affect the efficacy of medication EC. If you weigh over 165 pounds, levonorgestrel EC may be less effective, and if you weigh 195 points or more, ulipristal acetate may be less effective. You may want to consider an IUD instead of medication EC.

The best way to prevent pregnancy is to use a reliable regular birth control method such as condoms, birth control pills, vaginal ring, patch, depo, implant or IUD, or to not have sexual intercourse.

Is emergency contraception (EC) safe?

Yes. Millions of people have used EC without any problems. Anyone with a uterus can take EC. Even people who can’t take hormonal birth control because of a medical condition (migraines, heart disease, liver disease, breastfeeding, and previous ectopic pregnancy) can take EC.

Does emergency contraception (EC) cause birth defects?

Emergency contraception does not cause birth defects or affect the health of potential future pregnancies and children.

Does emergency contraception (EC) have any side effects?

Side effects of EC are usually absent or mild. The most common side effects include nausea and irregular bleeding. Other less common side effects may include vomiting, breast tenderness, fatigue, dizziness, headache, and menstrual cramps; but these side effects most often go away after 1-2 days. If you experience nausea after using EC, you can try over-the-counter medicines such as Dramamine II or Bonine. If you vomit within 3 hours of taking EC, talk to your health care provider because you may need to take another dose of EC.

Where can I get emergency contraception?

In the United States, anyone can get Plan B One-Step™ and other brands of levonorgestrel at most pharmacies without a prescription. You can also get Ella™ at a pharmacy, but you will need a prescription. You will need to be seen at a clinic, such as your primary care, GYN’s office, or Planned Parenthood, to have an IUD placed in your uterus. EC is not available in all pharmacies, so you may need to check multiple locations.

If you have questions about EC, use the EC website to find a health care provider or pharmacy. Be ready to answer the following questions:

When was the first day of your last menstrual period?
When was the exact date and time of unprotected PIV sex?
What types of birth control have you have used in the past?

Can I use emergency contraception as my regular form of birth control?

EC is not meant to be a regular method of birth control. It’s meant to be a one-time emergency treatment. EC can be used when a condom breaks, when a diaphragm or cervical cap gets moved, or any time when unprotected PIV sex occurs. You should not use EC as your only protection against pregnancy, because this method doesn’t work as well as other types of birth control. In addition, EC does not protect against sexually transmitted infections.

When can I expect my next menstrual period after I have taken emergency contraception?

If you have any problems after you take EC, you should contact your health care provider.

What if I have problems after I have taken emergency contraception (EC)?

If you have any problems after you take emergency contraception, you can contact your health care provider.

You should definitely contact your health care provider if:

You do not get your period within 3 weeks after taking EC.
You have very bad abdominal (belly) pain.
You are spotting (you notice small amounts of blood on your underwear in between your menstrual periods).
Your next menstrual period is very light.
You are feeling lightheaded or dizzy.

Do I need to do anything else to prevent pregnancy after I have taken emergency contraception?

Yes. You should talk to your health care provider about using a regular type of birth control method. Until you have your next menstrual period, it is best not to have sexual intercourse. If you decide to have PIV sex, make sure to use a barrier method (condom), every time, even if you are using hormonal birth control (pills, patch, or ring). After taking Plan B One-Step®, you can start hormonal birth control (pills, patch, or ring) right away, but you should wait 5 days after taking Ella™ to use these methods because they may prevent the EC from working. Find out more about birth control methods so you can start thinking about what method will be best for you.

We hope that you have learned a lot about EC and that we have answered your questions. Below are the key points to remember about EC so you can be a resource to your family, friends, and others.

Key Points to Remember about Emergency Contraception (EC):

Emergency contraception (EC) is a safe treatment to help prevent pregnancy in people with uteruses who have had unprotected PIV (penis-in-vagina) sex.
EC will NOT cause an abortion.
Plan B One-Step® does not work after ovulation.
EC does NOT prevent sexually transmitted infections (STIs) or HIV.
Emergency contraception does not guarantee that pregnancy will be prevented. The best way to prevent pregnancy is to use a reliable birth control method or to not have sexual intercourse.
Weight may decrease the effectiveness of medication EC.
Many EC products are available to all people in the United States without a prescription, including Plan B One-Step®, Next Choice One Dose®, MyWay®, AfterPill™, and other single-dose 1.5mg Levonorgestrel products.
Ella™ (Ulipristal acetate or UPA) is available with a prescription.
The ParaGard® (IUD) and Mirena® IUD are available at some health centers and clinics. An IUD must be inserted by a health care provider.
You should take a pregnancy test if you do NOT get your period within 3 weeks after taking EC.
Abdominal pain and/or heavy or unusual menstrual bleeding after taking EC is not normal and should be reported to your health care provider right away.
After you take EC, a backup method of birth control (condoms) should be used for at least 7 days or you should not have sex during this time. Condoms should be used every time you have sexual intercourse to prevent STIs.
Talk with your health care provider about your options and decide if you want an advanced prescription, just in case you need it in the future.
Be sure to talk with your health care provider about how you can prevent pregnancy and stay healthy.

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