Emergency contraception can prevent pregnancy after unprotected sex or if your contraceptive method has failed – for example, a condom has split or you've missed a pill.
There are two types:
At a glance: emergency contraception
The emergency pill
The IUD as emergency contraception
Where to get emergency contraception
Contraception for the future
There are two kinds of emergency contraceptive pill. Levonelle has to be taken within 72 hours (three days) of sex, and ellaOne has to be taken within 120 hours (five days) of sex. Both pills work by preventing or delaying ovulation (release of an egg). Emergency contraception is best taken as soon as possible to be effective.
The IUD can be inserted into your uterus up to five days after unprotected sex, or up to five days after the earliest time you could have ovulated. It may stop an egg from being fertilised or implanting in your womb.
Emergency contraception does not protect against sexually transmitted infections (STIs).
Levonelle contains levonorgestrel, a synthetic version of the natural hormone progesterone. In a woman’s body, progesterone plays a role in ovulation and preparing the uterus for accepting a fertilised egg.
It’s not known exactly how Levonelle works, but it’s thought to work primarily by preventing or delaying ovulation. It does not interfere with your regular method of contraception.
ellaOne contains ulipristal acetate, which stops progesterone working normally. It prevents pregnancy mainly by preventing or delaying ovulation.`
Levonelle and ellaOne do not continue to protect you against pregnancy. This means that if you have unprotected sex at any time after taking the emergency pill you can become pregnant.
Even if you are starting or continuing another method of hormonal contraception, it may not be effective immediately. You will need to use condoms or avoid sex until the contraception is working effectively.
The time it takes for contraception to become effective depends on the emergency contraceptive pill and the method of hormonal contraception being started. Your doctor or nurse will tell you when you can start hormonal contraception and how long you will need to take additional precautions to prevent an unintended pregnancy.
Levonelle and ellaOne are not intended to be used as a regular form of contraception. However, you can use emergency contraception more than once in a menstrual cycle if necessary.
You can get contraception at:
It can be difficult to know how many pregnancies the emergency pill prevents, because there is no way to know for sure how many women would have got pregnant if they did not take it.
A study published in 2010 showed that of 1,696 women who received the emergency pill within 72 hours of sex, 37 became pregnant (1,659 did not). Of 203 women who took the emergency pill between 72 and 120 hours after unprotected sex, there were three pregnancies.
Find out more about the research on the effectiveness of both emergency contraception pills.
However, it's important to remember that the sooner you take emergency contraception after sex, the more effective it will be.
After taking the emergency contraceptive pill, most women will have a normal period at the expected time. However, you may have your period later or earlier than normal.
If your period is more than seven days late, or is unusually light or short, contact your GP as soon as possible to check for pregnancy.
Most women can use the emergency contraceptive pill. This includes women who cannot usually use hormonal contraception, such as the combined pill and contraceptive patch. Girls aged under 16 years old can also use the emergency contraceptive pill.
The World Health Organisation (WHO) does not identify any medical condition that would mean a woman shouldn’t use Levonelle.
The manufacturer of ellaOne advises that it should not be used by women who:
ellaOne may not be effective in women who are taking liver enzyme-inducing medication.
Levonelle can be taken while breastfeeding. Although small amounts of the hormones contained in the pill may pass into your breast milk, it is not thought to be harmful to your baby.
The safety of ellaOne during breastfeeding is not yet known. The manufacturer recommends that you do not breastfeed for one week after taking this pill.
You may need to take the emergency pill if you:
If you have taken Levonelle, then you should:
You should then continue taking your regular contraceptive pill as normal.
You will need to use additional contraception, such as condoms, for:
If you have taken ellaOne, you will need to wait at least five days before taking your next contraceptive pill, applying a new patch or inserting a new ring. You should then use additional contraception, such as condoms, while waiting to restart your contraceptive method and then for:
Taking the emergency contraceptive pill has not been shown to cause any serious or long-term health problems. However, it can sometimes have side effects. Common side effects include:
Less common side effects include:
If you are concerned about any symptoms after taking the emergency contraceptive pill, contact your GP or speak to a nurse at a sexual health clinic. You should talk to a doctor or nurse if:
The emergency contraceptive pill may interact with other medicines. These include:
ellaOne cannot be used if you are already taking one of these medicines, as it may not be effective.
Levonelle may still be used, but the dose may need to be increased – your doctor or pharmacist can advise on this.
There should be no interaction between the emergency pill and most antibiotics. Two enzyme-inducing antibiotics (called rifampicin and rifabutin), used to treat or prevent meningitis or TB, may affect ellaOne while they’re being taken and for 28 days afterwards.
If you want to check that your medicines are safe to take with the emergency contraceptive pill, ask your GP or a pharmacist. You should also read the patient information leaflet that comes with your medicines.
You may be able to get the emergency contraceptive pill in advance of having unprotected sex if:
Ask your GP or nurse for further information on getting advance emergency contraception.
The intrauterine device (IUD) is a small, T-shaped contraceptive device made from plastic and copper. It’s inserted into the uterus by a trained health professional. It may prevent an egg from implanting in your womb or being fertilised.
If you’ve had unprotected sex, the IUD can be inserted up to five days afterwards, or up to five days after the earliest time you could have ovulated, to prevent pregnancy. It’s more effective at preventing pregnancy than the emergency pill, and it does not interact with any other medication.
You can also choose to have the IUD left in as an ongoing method of contraception.
There are several types of IUD. Newer ones have more copper and are more than 99% effective. Fewer than two women in 100 who use a newer IUD over five years will get pregnant. IUDs with less copper in them are less effective than this, but are still effective. The IUD is more effective than the emergency pill at preventing pregnancy after unprotected sex.
Most women can use an IUD, including women who have never been pregnant and those who are HIV positive. Your GP or clinician will ask about your medical history to check if an IUD is suitable for you.
You should not use an IUD if you have:
Women who have a heart condition should consult their GP or cardiologist before having an IUD fitted.
The IUD should not be inserted if there is a risk that you may already be pregnant. The IUD can be used safely if you’re breastfeeding, but the risk of complications during insertion is slightly higher.
Complications after having an IUD fitted are rare, but can include pain, infection, damage to the womb or expulsion (the IUD coming out of your womb). If you use the IUD as an ongoing method of regular contraception, it may make your periods longer, heavier or more painful.
The emergency IUD will not react with any other medication.
You can get the emergency contraceptive pill and the IUD for free from:
You can also get the emergency contraceptive pill free from:
The doctor or nurse you see may ask for the following information:
You can buy the emergency contraceptive pill from most pharmacies if you're aged 13 or over. The cost varies, but it will be around £30 to £35.
If you're not using a regular method of contraception, you might consider doing so in order to lower the risk of unintended pregnancy. Long-acting reversible contraception (LARC) offers the most reliable protection against pregnancy, and you don't have to think about it every day or each time you have sex.