• Options include levonorgestrel, ulipristal acetate, or a copper intrauterine device (IUD).
• The choice of emergency contraception should be made by the woman, taking into account her risk of becoming pregnant, her need to avoid pregnancy, which methods can be used in her current situation, and the availability of emergency contraception services.
• Levonorgestrel
• Levonorgestrel is available as a 1.5 g single dose tablet.
• Levonorgestrel can be used up to 72 hours (3 days) after unprotected sexual intercourse, but its effectiveness diminishes quite rapidly with time [FFPRHC, 2006b].
• Pharmacies will not provide levonorgestrel without a prescription when the time since unprotected sexual intercourse is greater than 72 hours, as this would be contrary to the product licence and guidance from the Royal Pharmaceutical Society [ABPI Medicines Compendium, 2004a; RPSGB, 2004].
• Levonorgestrel can be used more than once in a cycle if clinically indicated; however, if unprotected sexual intercourse occurs less than 12 hours after taking levonorgestrel, further emergency contraceptive treatment is not required [FFPRHC, 2006b].
• Ulipristal acetate
• Ulipristal acetate is available as a 30 mg single dose tablet.
• It can be used up to 120 hours (5 days) after unprotected sexual intercourse, and its efficacy is maintained over the 120 hours.
• Safety and efficacy of ulipristal acetate has only been established in women 18 years and older.
• It is not advisable to take ulipristal acetate more than once in a cycle as the safety and efficacy of repeated exposures has not been studied.
• Copper IUD
• A copper IUD (or advice on how to obtain one) should be offered to all women attending for emergency contraception, even if they present within 72 hours of unprotected sexual intercourse [FFPRHC, 2006b].
• Ideally, an emergency IUD should be fitted at first presentation, but insertion can be offered later, at the woman's convenience; in this case, levonorgestrel emergency contraception should always be given in the interim [FFPRHC, 2006b].
• If facilities are unavailable for emergency IUD insertion, local referral mechanisms should facilitate timely access to a specialist who can provide this service [FFPRHC, 2006b].
• The IUD can be used up to 5 days after unprotected sexual intercourse; it can also be used up to 5 days after ovulation and after multiple episodes of unprotected sexual intercourse [FFPRHC, 2006b].
• For more information, see:
• Issues for oral levonorgestrel.
• Issues for oral ulipristal acetate.
• Issues when advising an IUD.

Evidence indicates that levonorgestrel, ulipristal acetate, and copper IUDs are safe and effective, but that levonorgestrel and ulipristal acetate have a higher failure rate than copper IUDs. Women may find the higher failure rate of levonorgestrel or ulipristal acetate unacceptable in some circumstances.

There are no randomized controlled trials (RCTs) comparing the copper IUD with a hormonal method, no good RCTs comparing emergency contraceptive methods with placebo, and no cost-effectiveness studies. However, evidence from studies of IUDs used to provide long-term contraception can be applied to their use for emergency contraception. There is an indirect but convincing body of evidence on levonorgestrel emergency contraception.

• Levonorgestrel. There is a convincing body of evidence that levonorgestrel is effective, but its failure rate may be clinically important. There is no concern over its safety.
• Trials comparing different hormonal methods of emergency contraception provide evidence that levonorgestrel (a progestogen) is more effective than the Yuzpe method (combined oestrogen and progestogen). Furthermore, there is evidence that the Yuzpe method is more effective than no treatment [Trussell et al, 1999].
• Levonorgestrel becomes progressively less effective the longer the delay after unprotected sexual intercourse. See Effect of delay since intercourse.
• If the woman is already pregnant, repeated use of levonorgestrel will not induce abortion and is unlikely to harm the fetus [FFPRHC, 2006b]. This conclusion is based on clinical experience with levonorgestrel and other hormonal contraceptives (progestogen only, and combined oestrogen-progestogen formulations) [Grimes and Raymond, 2002].
• Ulipristal acetate. There is evidence that ulipristal acetate is effective when used up to 120 hours (5 days) after unprotected sexual intercourse, but its failure rate may be clinically important.
• One randomized controlled trial comparing ulipristal acetate with levonorgestrel provides evidence that it is at least as effective as levonorgestrel when used as emergency contraception within 72 hours of unprotected sexual intercourse.
• Limited evidence also shows that the efficacy of ulipristal acetate is maintained between 72 and 120 hours.
• Copper IUD. There is good evidence that the copper IUD is effective when used as long-acting contraception, with low failure rates and a low probability of serious complications or adverse effects.
• In trials of long-term contraceptive methods, IUDs with at least 380 mm² copper were more effective than IUDs with smaller areas of copper. The failure rates are low: fewer than 2 pregnancies would be expected in 100 women using the 380 mm² copper IUD for 5 years [National Collaborating Centre for Women's and Children's Health, 2005].
• The risk of pelvic inflammatory disease after IUD insertion is less than 1 in 100 in women who are at low risk of sexually transmitted infections [National Collaborating Centre for Women's and Children's Health, 2005].
• The risk of uterine perforation is less than 0.1% and is related to the skill of the person inserting the IUD [National Collaborating Centre for Women's and Children's Health, 2005].

For more information, see:

• Oral levonorgestrel
• Oral ulipristal acetate
• IUDs in emergency contraception