Quick answer

What is emergency contraception used for?

Emergency contraception prevents pregnancy after unprotected sex or contraceptive failure. The levonorgestrel pill works up to 72 hours (most effective within 24 hours); ellaOne up to 120 hours. The copper IUD is the most effective option — up to 5 days after sex — and provides ongoing contraception. Available free from GP surgeries, sexual health clinics, and some 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.

Options available

Levonorgestrel pill (Levonelle, generic)

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

Ulipristal acetate (ellaOne)

  • single tablet
  • works up to 120 hours (5 days) after unprotected sex
  • may be more effective than levonorgestrel between 3 and 5 days
  • prescription only — GP, pharmacy (via PGD scheme), or clinic
  • can interfere with regular hormonal contraception — use condoms until next period

Copper IUD (intrauterine device)

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

How emergency 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 from:

  • GP surgeries — same-day appointments 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 — any GP surgery or clinic can help.

Do not delay — effectiveness drops with time.

After taking emergency contraception

Your next period:

  • may come early or late
  • if more than 7 days late, do a pregnancy test
  • if light or unusual, test anyway

Side effects (usually mild):

  • nausea — take with food; anti-sickness medicine if needed
  • headache, tiredness
  • breast tenderness
  • irregular bleeding before next period

Ongoing contraception:

  • start or continue regular contraception as advised
  • after ellaOne, use condoms until your next period if on hormonal contraception
  • consider a long-term method — IUD, implant, pill — to reduce future emergency need

Copper IUD as first choice

If you want the most effective option and ongoing contraception, the copper IUD is recommended by NICE — especially if:

  • more than 72 hours have passed (still works up to 5 days)
  • BMI over 26 (levonorgestrel may be less effective)
  • you want long-term contraception afterward

Contact a clinic immediately — fitting slots may be limited.

Emergency contraception and 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 2 weeks after exposure for accurate results
  • HIV PEP (post-exposure prophylaxis) may be needed within 72 hours of high-risk exposure — attend A&E or sexual health clinic urgently

When emergency contraception fails

If you become pregnant despite emergency contraception:

  • the pregnancy is not harmed by pills taken before implantation
  • discuss options with a GP or pregnancy advisory service
  • ectopic pregnancy — seek urgent help for abdominal pain, shoulder tip pain, or bleeding with positive pregnancy test

Repeated use

Emergency contraception is safe for repeated use but not recommended as regular contraception. If you need it more than once, discuss reliable ongoing contraception with a GP or clinic — implants, IUDs, and pills are more effective long-term.

Under 16s

Confidential contraception and emergency contraception is available to under-16s who understand the information and cannot be persuaded to involve a parent. Sexual health services and GPs provide confidential care.

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.

Common questions

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?
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 all ages — ask locally.
What is the copper IUD for emergency contraception?
A copper coil inserted into the womb within 5 days of unprotected sex prevents over 99% of pregnancies. It also provides ongoing contraception for 5 to 10 years. The most effective emergency option — requires appointment for fitting.
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 effectiveness of regular hormonal contraception — use condoms until your next period. After levonorgestrel, continue or restart regular contraception as advised. A pharmacist or GP explains what applies to your situation.

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