Emergency contraception


  • There are no serious side effects of using emergency contraceptive pills
  • Reduces risk of pregnancy if you haven't used contraception, or if your contraception has failed.

The emergency contraception (EC) pill (sometimes called the ‘morning after pill’) can be taken after unprotected sex to prevent pregnancy.

There are two types of hormonal emergency contraception; one which has to be taken within three days of unprotected sex, and the other within five days. The non-hormonal coil (IUD) is the most effective emergency contraception if inserted up to five days after unprotected sex.

The emergency contraceptive pill is by far the most popular method of emergency contraception, and can be bought without prescription from most pharmacies.

*most effective within 24 hours. Effectiveness decreases with time since unprotected sex
**can make earlier or later

How it works

Things to consider

Emergency contraceptive pills or emergency IUDs do not protect against STIs. You should use condoms to protect yourself from STIs.

STIs can pass from one person to another during sex, especially if you don’t use a condom. It is a good idea to get tested, especially if you have recently changed partners. Most infections can be cured.

Using the emergency contraceptive pill repeatedly can disrupt your natural menstrual cycle.

What if?

You’re already using another form of contraception:

  • ulipristal acetate (UPA) may be less effective if you take another type of hormonal contraception 7 days before, or within the 5 days after taking a UPA pill. This includes long-acting methods like the implant, IUS coil and injection - even if it has run out.
  • levonorgestrel (LNG) does not affect other types of hormonal contraception. If you usually take the contraceptive pill, or use the patch or ring, continue as normal but use extra protection (condoms) for the first 7 days (2 days for progestogen only pills).
  • The IUD will not interfere with your regular method of contraception and will continue to give you protection against pregnancy for the rest of the cycle - you can choose to keep it for ongoing contraception.

You’ve already taken emergency contraception in the last 7 days?

If you have taken levonorgestrel (LNG) in the last 7 days and you need emergency contraception again then you should take levonorgestrel again.

If you have taken ulipristal acetate (UPA, ellaOne) in the last 7 days and you need emergency contraception then you should take ulipristal acetate again.

Emergency contraceptive pills can become less effective at preventing pregnancy if:


Most women can take the emergency contraceptive pill. This includes women who cannot usually use hormonal contraception, such as the combined pill and contraceptive patch.

Ulipristal acetate (UPA) is not suitable for women who:

  • are allergic to any of the components of the drug
  • have severe asthma that is not properly controlled by steroids
  • have hereditary problems with lactose metabolism.

Side effects & risks

Common Rare
Short term:

Next period earlier or later than usual.

Can make you feel sick, dizzy or tired, or give you a headache, tender breasts or abdominal pain.

Some women using Ulipristal acetate (UPA) experience painful periods, mood swings, and muscle or back pain.

Long term:


You can take Levonelle emergency contraceptive pills while breastfeeding. If you choose the ellaOne pill, you will need to wait 7 days after taking the tablets before feeding your child. Feed with an alternative, like formula milk and discard your breast milk during this time.

You may be able to use the non-hormonal coil for emergency contraception while breastfeeding, but you’ll need to discuss this with the health professional fitting the IUD.

Thumb up 7   Thumb down 0

Yes – Levonorgestrel (LNG) becomes less effective the longer you wait to take it. A trial undertaken by the World Health Organization (WHO) indicated that levonorgestrel (the drug in LNG) prevented:

  • 95% of expected pregnancies when taken within 24 hours of sex
  • 85% if taken within 25-48 hours
  • 58% if taken within 49-72 hours.

Thumb up 24   Thumb down 2

The emergency contraceptive pill will not prevent future pregnancies if you have unprotected sex again, so you should make sure you are taking your contraception correctly.

For Levonorgestrel (LNG): If you’re starting or restarting a hormonal contraceptive like the pill, patch, ring or injection, wait for 5 days after taking ulipristal acetate. It can make hormonal contraception less effective. Use additional contraception, such as condoms:

  • for 7 days with the patch, the ring, the combined pill and the contraceptive injection (9 days for Qlaira pill)
  • for 2 days with the progestogen only pill.

For Ulipristal acetate (UPA): If you forgot your regular pills, did not use the patch or vaginal ring correctly, or want to start using hormonal contraception, you should wait for 5 days after taking UPA. This is because UPA can can reduce the effect of hormonal contraception.

  • Use additional contraception, such as condoms:
  • for 7 days with the patch, the ring, the combined pill and the contraceptive injection (9 days for Qlaira pill)
  • for 2 days with the progestogen only pill.

This gives the contraception time to become effective.

Thumb up 3   Thumb down 1

Your period is likely to come on time or a few days early or late. Sometimes it can be a week late and sometimes even later. You may have some irregular bleeding after you take the pill, and before your next period. This can range from spotting to quite heavy bleeding. If your period is over a week late, take a pregnancy test.

Thumb up 7   Thumb down 0

Your period may come on time or a few days early or late. If your period is over a week late, take a pregnancy test.

Thumb up 5   Thumb down 0

The sooner you take Levonorgestrel (LNG) or Ulipristal acetate (UPA), the more effective it will be.

If your next period is more than seven days late, or is unusually light or short, contact your GP as soon as possible to check for pregnancy.

Thumb up 2   Thumb down 0

Emergency hormonal contraceptive pills are a very good option to reduce your risk of pregnancy after unprotected sex. However, using emergency hormonal contraceptive pills repeatedly is much less effective than using a regular method of contraception as they are only effective if taken before you have ovulated. Therefore they are not recommended as a regular method of contraception.

It is important to note that if you have taken emergency hormonal contraception once, it will not protect you from pregnancy if you have sex again during that cycle - in this situation you would have to take another dose of emergency contraceptive pill or have an IUD (copper coil) fitted.

Emergency hormonal contraceptive pills can be taken more than once in during a menstrual cycle. However, if you take two emergency contraceptive pills within 7 days, they must be the same type of pill, they will be less effective if you take a LNG pill and a UPA pill within the same week.

Thumb up 3   Thumb down 0

If you are unsure about either of these things, and you think you may have had unprotected sex in the last 72 hours, you should take emergency contraception.

Thumb up 10   Thumb down 0

Emergency contraceptive pills can become less effective at preventing pregnancy if you are taking other medicines (including those used to treat epilepsy, HIV and TB, other antibiotics and the herbal medicine St John’s Wort).

  • Ulipristal acetate (UPA) cannot be used if you are already taking one of these medicines, as it may not be effective
  • Levonorgestrel (LNG) may still be used, but the dose may need to be increased – your doctor or pharmacist can advise on this
  • Ask your GP, clinician or pharmacist and read the information that comes with your medicine
  • Ulipristal acetate (UPA) may not be suitable for people who are using proton pump inhibitors such as omeprazole (antacids that regulate their stomach acid levels).

Thumb up 4   Thumb down 0

If you need emergency contraception for recent unprotected sex, you will be asked:

  • when you have had unprotected sex in your current menstrual cycle
  • the date your last period started
  • sometimes you'll be asked the usual length of your cycle (from the start of one period to the next)
  • details of any contraceptive failure (such as how many pills you may have missed, and when)
  • if you use medication
  • your medical history and sexual health history.

Thumb up 8   Thumb down 0

Ask your GP or nurse if you want to get the emergency contraceptive pill in advance if:

  • You are worried about your contraceptive method failing
  • You are going on holiday
  • You cannot get hold of emergency contraception easily.

Thumb up 18   Thumb down 0

Where can I get it?

You can get emergency contraception free from GPs and all sexual health clinics, as well as most NHS walk-in centres, pharmacies, minor injuries units and A&E.

If your local pharmacy cannot give you emergency contraception for free, you should still be able to buy it. If you are over 16 you can buy Levonorgestrel (LNG) and if you are aged 18 or over, you can buy Ulipristal acetate (UPA). You may be asked to show ID. It will cost around £30.

Depending on whether we are commissioned to provide emergency contraception in you area you may be able to order from SH:24 for free.

Contraception for the future

If you're not using a regular method of contraception, you might consider doing so in order to lower the risk of unintended pregnancy.

There are many reliable types, and if the first type you try is not quite right, you may try a few methods before you find one that suits your lifestyle.

Use our contraception comparator, and choose two contraceptive options to compare side by side.

Or, take 2 minutes to answer a simple set of health questions via our medical suitability chatbot, to check which methods are likely to be suitable for you.