Emergency Contraception

What is emergency contraception?

Emergency contraceptive

Emergency contraception (EC) is used after unprotected sexual intercourse or when contraception may have not worked properly, to reduce the risk of an unintended pregnancy. This might include if you didn't use contraception, forgot to take one of your usual contraceptive pills, the condom broke during sex or you were sexually assaulted. There are three main methods of emergency contraception available:

  1. A 1.5mg single dose levonorgestrel emergency contraceptive pill (LNG-ECP), licensed for use up to 72 hours (three days) after unprotected sex; available from pharmacies and Family Planning NSW as an over the counter medication
  2. A 30mg single dose ulipristal acetate (UPA) tablet licensed for use up to 120 hours (five days) after unprotected sex; available from pharmacies and Family Planning NSW as an over the counter medication.
  3. Insertion of a copper intrauterine device (IUD) within 5 days of unprotected sex, which also provides very effective long term contraception

This fact sheet focuses on the two available emergency contraceptive pills (ECPs). For more information about copper IUDs please see our fact sheet The copper IUD: https://www.fpnsw.org.au/health-information/individuals/contraception/copper-iud

An earlier method of emergency contraception called the Yuzpe method is made up of a combination of combined oral contraceptive pills. It is less effective than the newer methods and is only advised if none of the other methods are available.

How do the emergency contraceptive pills work?

Evidence gathered by the World Health Organization has found that both emergency contraceptive pills work by stopping or delaying ovulation (the release of an egg from a woman's ovaries). They may also prevent the egg and sperm from meeting. Emergency contraceptive pills do not prevent implantation of a fertilised egg and do not cause an abortion. If LNG-ECP or UPA is accidentally taken during pregnancy they do not cause harm to the developing embryo or fetus.

How do you take EC?

Both types of emergency contraceptive pill (ECP) should be taken as soon as possible after unprotected sex to maximise the chance of delaying ovulation. The LNG-ECP is licensed up to 72 hours after unprotected sex, but still offers some effectiveness up to 96 hours afterwards. It can be used more than once in a cycle if needed. UPA is effective for 120 hours after unprotected sex. The LNG-ECP should not be used in the same menstrual cycle as UPA.

If vomiting occurs less than two hours after taking LNG-EC, or less than three hours after taking UPA, another dose should be taken. If vomiting occurs after this time, there is no need to take another dose.

Since some medications, including certain anti-epileptic medications, can reduce the effectiveness of the emergency contraceptive pills, be sure to discuss any medications you are taking with the pharmacist or doctor.

How effective is emergency contraception?

  • LNG-ECP: estimated to prevent approximately 85% of expected pregnancies if taken within 3 days of unprotected sex
  • UPA: more effective than LNG-ECP with superior effectiveness up to 120 hours after unprotected sex1
  • Copper IUD: the most effective method with a failure rate of less than 1% if inserted within 5 days of unprotected sex2

Remember, no method of emergency contraception is 100% effective at preventing an unintended pregnancy. A followup pregnancy test may be needed to check for pregnancy. This should be discussed with the pharmacist or doctor.

Do the ECPs have any side effects?

LNG-ECP and UPA are very safe with no serious or longlasting side-effects. There is a small chance of nausea, breast tenderness or headache.

When to expect your period

Most women have a period around the expected time but taking an ECP may result in a period starting earlier or later than expected. Sometimes bleeding may occur which is not related to a period. If the period is late, light or unusual in any way it is important to discuss this with a pharmacist, doctor or family planning clinic as a pregnancy test may be needed.

Who can take the ECP?

Almost all women can take one of the emergency contraceptive pills but it is important for the pharmacist or doctor to know if they have any allergies or serious medical conditions.

If women are breastfeeding and take UPA for emergency contraception, they should express and discard breastmilk for one week after taking UPA, because it is detected in breastmilk for up to five days after use. It may be more convenient to take the LNG-ECP as they can continue to breast feed.

Ongoing contraception

ECPs do not provide ongoing contraception and may delay ovulation. It is important to keep using other contraception such as condoms for the rest of the cycle until the next period in case of ovulation AFTER taking the ECP. Otherwise the woman could still become pregnant.

It is not recommended to take a progestogen-containing method of contraception within 5 days of UPA as it appears to reduce the effectiveness of the UPA. This includes the combined pill, vaginal ring, progestogen-only pill, implant, and depot injection. Talk to a doctor or pharmacist about starting or restarting hormonal contraception after taking UPA.

With LNG-EC, it is possible to continue or start a hormonal method of contraception immediately after taking it.

Follow Up

While most women do not need follow-up after taking an emergency contraceptive pill, they should talk to their GP, Family Planning clinic or FPNSW Talkline if:

  • their period is more than a week late
  • their period is light or unusual in any way
  • they have any other concerns
  • they wish to discuss your ongoing contraception needs.

They may need to do a pregnancy test.

For Further Information

Where to get EC?

  • LNG-EC and UPA - from a pharmacy without a prescription (over the counter) or from a Family Planning NSW clinic
  • Copper IUD - contact Family Planning NSW to discuss the possibility of copper IUD insertion within the 5 day timeframe at a Family Planning clinic or by a trained GP or gynaecologist.


1 Glasier et al. Ulipristal acetate versus levonorgestrel for emergency contraception: a randomised non-inferiority trial and meta-analysis. Lancet. 2010 Feb 13;375(9714):555-62

2 Cleland K, Zhu H, Goldstuck N, Cheng L, Trussell J. The efficacy of intrauterine devices for emergency contraception: a systematic review of 35 years of experience. Human Reproduction. 2012;27(7):1994-2000

Adapted from:
World Health Organization. Fact sheet on the safety of levonorgestrel-alone emergency contraceptive pills (LNG ECPs). [Online, updated 2010]. Available at: http://whqlibdoc.who.int/hq/2010/WHO_RHR_HRP_10.06_eng.pdf. Accessed 2 May 2016.
Faculty of Sexual and Reproductive Healthcare. Clinical guidance: Emergency Contraception.[Online,updated 2012] Available at: http://www.fsrh.org/pdfs/CEUguidanceEmergencyContraception11.pdf. Accessed on 23 May 2016.

Further Information

The information in this factsheet has been provided for educational purposes only. FPNSW has taken every care to ensure that the information is accurate and up-to-date at the time of publication. Individuals concerned about any personal reproductive or sexual health issue are encouraged to seek advice and assistance from their health care provider or visit a Family Planning clinic.

Reviewed: January 2017 | FPNSW 01/17

This factsheet tells you how the emergency contraceptive pill works; how long after unprotected sex you can take it.

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