Emergency Contraception (EC) and the IUD both work up to 5 days after unprotected sex. You may have longer with the IUD than 5 days for it to be fitted.

EC attempts to stop a pregnancy from occurring following either unprotected sex or failure of regular contraception. The IUD stops the egg being fertilised or implanting in the uterus.

Emergency Contraception pills work mainly by stopping/delaying ovulation. They are only likely to work if they are taken before the egg is released.

About Emergency Contraception


  • If taken/fitted within 5 days of unprotected sex, emergency contraception can prevent pregnancy
  • The IUD can be kept in and become a regular ongoing method of contraception


  • IUD insertion can be uncomfortable, but does not usually take longer than 5 minutes
  • There may be some temporary hormonal side effects to the oral contraceptive pill, including headaches, abdominal pain, dizziness, disruption to periods for a while. Most go away within a few days
  • Oral emergency contraception does not offer any ongoing contraceptive cover
  • Oral emergency contraception may be less effective if you vomit within 3 hours of taking it
  • No protection against STIs

More information

  • A pregnancy test is recommended 3 weeks after emergency contraception to ensure it has worked
  • Some medicines may reduce the effectiveness of the oral emergency contraceptive pills
  • Some chemists may charge for the oral emergency contraceptive pill (between £25-£35)
  • It is FREE from sexual health/GUM clinics/GP’s
  • A tablet containing Ulipristal Acetate (UPA) is more effective at preventing pregnancy than a pill with levonorgestrel