Emergency Contraceptive Pills (ECPs) (Teen Corner)

Emergency Contraceptive Pills

What Are They?

The Emergency Contraceptive Pill (ECP), more commonly known as Plan B or "the morning-after pill," can be used to prevent pregnancy after unprotected sex or the failure of a primary birth control method. The emergency contraception pill is not an abortion pill and cannot interfere with an existing fetus or induce abortion if conception has already occurred. ECPs merely delay ovulation so that the female’s ovary takes longer to release the egg than usual. This prevents the sperm and the egg from meeting, and fertilization will not occur. While safe to use in emergency situations, ECPs should not be relied on as a regular form of birth control. ECPs are not as effective as birth control in the long term and may become quite expensive with repeated use. You can find the various forms of ECPs at your local drugstore or health clinic. You can take ECPs even if you have been previously pregnant or plan on becoming pregnant in the future.

To find a clinic near you that provides ECPs, or for more information, contact the Emergency Contraception Hotline at 1-800-584-9911. To find your local Planned Parenthood (another information resource for ECPs), call 1-800-230-PLAN.

The Copper IUD as an Emergency Contraceptive

The most effective form of emergency contraception (even more effective than the pill) is the copper intrauterine device (IUD). The copper IUD is a non-hormonal contraceptive that can prevent pregnancy if inserted by a healthcare practitioner within five days of unprotected sex. The copper IUD can then remain in place to prevent pregnancy for up to 10 years. Though the IUD has a relatively high up-front cost ($500-$900), there are no ongoing costs, and it requires only monthly thread checks by the user. Many healthcare centers will accept insurance, which may lower the cost.8

What Types are Available and How Do They Work?

Emergency contraceptive pills work in a similar way to birth control pills but utilize higher doses of hormones. ECPs can work in three different ways, depending on which stage of the menstrual cycle the female is experiencing. ECPs can prevent an egg from being released by an ovary, fertilization of the egg by the sperm, or implantation of the fertilized egg in the endometrium. If the pregnancy has already been established, the pill will not be effective and, again, will not harm or interfere with an existing pregnancy.

There are currently three different types of emergency contraceptives around the world:

  • Progestin-Only Pills contain levonorgestrel, which can either delay ovulation or prevent fertilization in order to minimize the risk of pregnancy (if taken within 5 days of unprotected sex). These pills lose effectiveness as time elapses, and can reduce the risk of pregnancy by up to 95% if taken within the first 24 hours after unprotected sex. Some examples of progestin-only pills are Plan B One-Step, Next Choice, and Levonorgestrel Tablets.6 Some brands have one pill, and others have two. Levonorgestrel tablets typically contain two pills with 0.75 mg levonorgestrel each. Though instructions may state to take the second dose 12 hours after the first, recent studies have shown that taking both 0.75 mg doses at once is just as effective as and causes no additional side effects than two 0.75 mg doses taken 12 hours apart.3

The i-pill is a common progestin-only ECP that is used outside of the United States. It is available over the counter without a prescription from a local chemist outlet. The i-pill must be taken within 72 hours of unprotected sex to prevent pregnancy and is more effective the sooner it is taken.6


  • Anti-Progestin Pills contain either ulipristal acetate or mifepristone and are found to be even more effective than progestin-only pills. These pills can be taken up to 5 days after unprotected sex and (unlike progestin-only pills) are equally as effective at preventing pregnancy for all 5 days. The pills containing ulipristal acetate are sold in the United States as ella and in Europe as ellaOne, but the pills containing mifepristone are currently available only in Armenia, China, Russia, and Vietnam.


  • Combination Pills (“combo pills”) contain both progestin and estrogen and can also be used as a form of emergency contraception. This type of ECP method contains the same hormones as regular birth control pills but in much higher doses. This mode of emergency contraception is more likely than progestin-only methods to cause adverse side effects, such as nausea. Combination pills also put females with a history of blood clots, stroke, or migraine at greater health risks (including an increased risk in heart disease and blood clot formation) than progestin-only pills. Researchers currently recommend progestin-only pills over combination pills for use as emergency contraception.1

Click here for information on the types of brands and doses that are safe to use. Common combination pill brands include Librel, Seasonale, and Seasonique.8

How Do I Use Them?

If you plan on using ECPs, it is wise to consult a doctor or pharmacist to learn of any side effects you may experience. Such side effects of ECPs may include, but are not limited to, changes in your period, nausea, lower abdominal pain, fatigue, headache, dizziness, and breast tenderness. If vomiting occurs after swallowing the emergency contraceptive pill(s), contact a doctor immediately to see if a repeat dose is necessary.

Some ECPs come in two high-dose pills, while Plan B One-Step is only one high-dose pill. Both types of ECPs are effective at preventing pregnancy if taken properly. With the two-pill system, one pill is taken within 3 days (but up to 5 days) after unprotected sex, and the second pill is taken 12 hours after the first. However, studies have shown that it is just as effective to take both 0.75 mg levonorgestrel pills at once than to separate the doses by 12 hours.3 With the one-pill system, only one pill is taken within five days after unprotected sex (the sooner the better!). You should begin your period within 10-12 days of taking ECPs.


When taken as directed, ECPs are highly effective at preventing pregnancy. ECPs are most effective within the first 72 hours after unprotected sex, but still retain some efficacy up to 5 days after unprotected sex. When taken within 24 hours of unprotected sex, ECPs are about 95% effective at preventing pregnancy. When taken about 72 hours after unprotected sex, progestin-only ECPs (both one-pill and two-pill brands) are about 89% effective at preventing pregnancy. Combined pills reduce the risk of pregnancy by about 75%. The copper IUD when used as an emergency contraceptive is about 99% effective in reducing pregnancy risk and can be left in place to provide ongoing contraception for up to 10 years. Since none of these methods are perfect, it is recommended to take a pregnancy test a few weeks after taking ECPs to ensure that pregnancy has not occurred.


The cost of ECPs can range anywhere from $10 to $70. The variation in cost depends on the type of pill, insurance coverage, your age, and location. ECPs are generally less expensive at family planning clinics like Planned Parenthood, some of which offer ECPs for free. Check with your local Planned Parenthood to learn more about how to get ECPs: 1-800-230-PLAN.

You May Want to Take Emergency Contraceptive Pills if the Following Situations Apply:

  • You have engaged in unprotected sex.
  • Your primary form of birth control failed (e.g. the condom broke, you forgot to take your birth control pill, your diaphragm slipped/was out of place, your male partner did not withdraw his penis quickly enough, etc.).
  • You have been sexually assaulted and your assailant inserted his penis into your vagina or ejaculated near or on your vaginal opening.

You Should Consult Your Doctor Prior to Taking Emergency Contraception if You have a History of the Following Conditions:

  • Heart attacks
  • Blood clots
  • Liver disease
  • Stroke
  • Breast cancer
  • Cancer of the reproductive organs
  • Migraine headaches

Advantages of Emergency Contraceptive Pills

  • They are highly effective at preventing pregnancy if used within 72 hours.
  • They can be taken privately and discretely.
  • Plan B One-Step is available over the counter without a prescription regardless of age. No government-issued identification card is required for purchase. Other types of ECPs can be purchased without a prescription if you are over the age of 17 years old (in the United States).
  • ECPs are NOT abortion pills; they simply interfere with fertilization and/or implantation.

Disadvantages of Emergency Contraceptive Pills

  • They do not protect against HIV or STIs.
  • They are not effective if conception has already occurred.
  • They can be expensive.
  • A prescription may be required if using ella or under the age of 17 years old (not required for Plan B One-Step).
  • Side effects such as nausea, headache, dizziness, and breast tenderness may occur.
  • Should not be used if you have already used ella since your last period.

Availability of Emergency Contraceptive Pills in the United States

As of April 2013, Plan B One-Step has been approved for over-the-counter sale to individuals of all ages in the United States without a prescription or government-issued identification card. Before this law took affect, the previous age requirement without a prescription was 17. Those under 17 years of age could only receive Plan B One-Step with a prescription from their healthcare provider.5

If you are required to obtain a prescription for ECPs for ella or other brands of emergency contraception, it is necessary to contact a doctor. ECPs are only prescribed to females, so males under the age of 17 cannot receive a prescription from their healthcare provider. If a male is over the age of 17 he can purchase ECPs with proof of age. If visiting a new medical clinic, be sure to provide a complete medical history to prevent any potential problems you may otherwise experience with the ECP. When obtaining the ECP over the counter at drugstores with a licensed pharmacist, be sure to bring a government-issued identification card with your proof of age. To find a pharmacy that provides ECPs near you, contact the Emergency Contraception Hotline at 1-800-584-9911 or Planned Parenthood at 1-800-230-PLAN.  

To learn more about emergency contraceptive laws in the United States, click here.4

To see the latest news on emergency contraception around the world, click here.


It is important to use one or more reliable forms of birth control for future sexual encounters, such as the pill, condom, or both. To learn more about contraceptives, click here.



1.     "Combination » Choices Pregnancy Services." Combination » Choices Pregnancy Services. N.p., 2012. Web. 20 Jan. 2014. <http://www.pregnancychoice.org/services/emergency-contraception/combinat....

2.     "Emergency Contraception." WHO. N.p., July 2012. Web. 20 Jan. 2014. <http://www.who.int/mediacentre/factsheets/fs244/en/>.

3.     "Emergency Contraception: Progestin-only Pills as Emergency Contraceptives." Princeton University, 12 Nov. 2013. Web. 20 Jan. 2014. <http://ec.princeton.edu/info/ecminip.html>.

4.     “Emergency Contraception State Laws.” National Conference of State Legislatures, 2014. Web. 18 Jan. 2014. <http://www.ncsl.org/research/health/emergency-contraception-state-laws.a....

5.     Fecteau, Jessica. "Plan B Emergency Contraceptive Changes Age Requirement for Purchasing Pill." Central Michigan Life. N.p., 17 Apr. 2013. Web. 20 Jan. 2014. <http://www.cm-life.com/2013/04/17/plan-b-emergency-contraceptive-changes....

6.     "I-pill Emergency Contraceptive Pills, Emergency Pill, Avoid Pregnancy." I-pill Emergency Contraceptive Pills, Emergency Pill, Avoid Pregnancy. N.p., n.d. Web. 20 Jan. 2014. <http://www.ipillwoman.piramal.com/main.htm>.

7.     "Morning-After Pill (Emergency Contraception)." The Morning-After Pill. Planned Parenthood, 2014. Web. 20 Jan. 2014. <http://www.plannedparenthood.org/health-topics/emergency-contraception-m....

8.     "Plan B One-Step®: Home." Plan B One-Step®: Home. Women's Capital Corporation, 2013. Web. 20 Jan. 2014. <http://www.planbonestep.com/>.


Last Updated 18 February 2014.