Quick answer

What is emergency contraception used for?

Emergency contraception is medicine or a device used to prevent pregnancy after unprotected sex or contraceptive failure. The levonorgestrel pill works up to 72 hours after sex, ellaOne up to 120 hours, and the most effective option, the copper IUD, up to 5 days. All are available free from GP surgeries, sexual health clinics, and pharmacies.

Emergency contraception prevents pregnancy after unprotected sex

Emergency contraception reduces the chance of pregnancy after unprotected sex, missed contraceptive pills, condom failure, or sexual assault. It is not the same as an abortion — it prevents pregnancy from establishing. The sooner you use it, the more effective it is. Several options are available free on the NHS in the UK.

Emergency contraception options available

Levonorgestrel pill (Levonelle, generic)

  • It is a single tablet containing a progestogen hormone.
  • It works up to 72 hours (3 days) after unprotected sex.
  • It is most effective within 24 hours, with about a 95% success rate.
  • It is available from pharmacies (often free for under-25s), GP surgeries and clinics.
  • It may be less effective in women over 70kg, so discuss alternatives with a pharmacist.

Ulipristal acetate (ellaOne)

  • It is taken as a single tablet.
  • It works up to 120 hours (5 days) after unprotected sex.
  • It may be more effective than levonorgestrel between 3 and 5 days after sex.
  • It is available on prescription only, from a GP, pharmacy (via a PGD scheme), or clinic.
  • It can interfere with regular hormonal contraception, so use condoms until your next period.

Copper IUD (intrauterine device)

  • It is a small copper device fitted into the womb.
  • It works up to 5 days after unprotected sex.
  • It is over 99% effective, making it the most reliable emergency option.
  • It also provides ongoing contraception for 5 to 10 years.
  • It requires an appointment at a GP surgery or sexual health clinic for fitting.
  • It may cause cramping during and after insertion.

How emergency contraceptive pills work

Emergency pills primarily delay or prevent ovulation, stopping an egg from being released. They may also affect sperm transport or fertilisation. They do not work if you have already ovulated and fertilisation has occurred, or if implantation has happened.

They are not abortifacients — they prevent pregnancy rather than ending an established one.

Where to get emergency contraception free on the NHS

Emergency contraception is available free on the NHS from several places:

  • GP surgeries, where same-day appointments are often available.
  • NHS sexual health (GUM) and contraception clinics.
  • many pharmacies, including free provision for under-25s (Brook, NHS schemes).
  • some A&E departments, especially after sexual assault.
  • walk-in centres.

You do not need to see your own GP, as any GP surgery or clinic can help. Do not delay seeking emergency contraception, since its effectiveness drops with time.

What to expect after taking emergency contraception

Your next period may come early or late. If it is more than 7 days late, take a pregnancy test, and do the same if it is unusually light or otherwise unusual, just to be safe.

Side effects are usually mild and can include nausea (which is eased by taking the pill with food, or with anti-sickness medicine if needed), headache, tiredness, breast tenderness, and irregular bleeding before your next period.

You should start or continue your regular contraception as advised. After taking ellaOne, use condoms until your next period if you are on hormonal contraception. It is also worth considering a long-term method, such as an IUD, implant or pill, to reduce the need for emergency contraception in future.

When the copper IUD is the best choice

If you want the most effective option along with ongoing contraception, the copper IUD is recommended by NICE, especially if more than 72 hours have passed since unprotected sex (it still works up to 5 days), if your BMI is over 26 (since levonorgestrel may be less effective), or if you want long-term contraception afterward. Contact a clinic immediately, as fitting appointments may be limited.

Does emergency contraception protect against STIs

Emergency contraception does not protect against sexually transmitted infections. If you had unprotected sex with a new partner or someone whose STI status is unknown, consider STI testing at a sexual health clinic, often recommended around 2 weeks after exposure for accurate results. HIV PEP (post-exposure prophylaxis) may also be needed within 72 hours of a high-risk exposure, so attend A&E or a sexual health clinic urgently if this applies to you.

What happens if emergency contraception fails

If you become pregnant despite using emergency contraception, the pregnancy is not harmed by pills taken before implantation. Discuss your options with a GP or a pregnancy advisory service. Seek urgent help for abdominal pain, shoulder tip pain, or bleeding alongside a positive pregnancy test, as these can be signs of an ectopic pregnancy.

Using emergency contraception more than once

Emergency contraception is safe to use more than once but is not recommended as a regular method of contraception. If you find you need it repeatedly, discuss reliable ongoing contraception with a GP or clinic, since implants, IUDs, and the pill are more effective for long-term use.

Emergency contraception for under-16s

Confidential contraception and emergency contraception are available to under-16s who understand the information given and cannot be persuaded to involve a parent. Sexual health services and GPs provide this care in confidence.

For everyday prevention, see our contraceptive pill guide and NHS contraception pages. The copper IUD and hormonal IUD (Mirena) are among the most effective long-term methods available.

Common questions about emergency contraception

How effective is the morning after pill?
Levonorgestrel (Levonelle) prevents about 95% of pregnancies if taken within 24 hours, falling to about 58% by 72 hours. EllaOne (ulipristal acetate) works up to 120 hours and may be more effective at 3 to 5 days. Neither is 100% — the copper IUD is more reliable.
Where can I get emergency contraception free?
Emergency contraception is available free from GP surgeries, NHS sexual health (GUM) clinics, contraception clinics, some pharmacies (including under-25 schemes), and some A&E departments. Many pharmacies provide levonorgestrel free to under-25s and sometimes to all ages, so it is worth asking locally.
What is the copper IUD used for as emergency contraception?
The copper IUD is a copper coil that is inserted into the womb within 5 days of unprotected sex and prevents over 99% of pregnancies. It also provides ongoing contraception for 5 to 10 years, making it the most effective emergency option. It requires an appointment for fitting at a GP surgery or clinic.
Does emergency contraception cause an abortion?
No. Emergency pills delay or prevent ovulation so an egg is not released to be fertilised. They do not work if implantation has already occurred. The copper IUD prevents fertilisation and implantation.
Will emergency contraception affect my regular contraception?
EllaOne may reduce the effectiveness of regular hormonal contraception, so you should use condoms until your next period. After levonorgestrel, you can continue or restart your regular contraception as advised. A pharmacist or GP can explain what applies to your situation.

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