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Contraception - emergency - Management
What advice should I give to a woman taking oral levonorgestrel emergency contraception?

  • Levonorgestrel emergency contraception is most effective if taken within 72 hours of unprotected sexual intercourse — the risk of failure increases with delay in taking it. It can also be taken up to 5 days after unprotected sexual intercourse, but pharmacies will require a prescription as this is outside the terms of its license.
  • Because levonorgestrel is not 100% effective, the woman should have a pregnancy test if her next menstruation is more than 5–7 days late, if bleeding is lighter than usual, or if she feels that she might be pregnant [FFPRHC, 2006b].
    • Guidelines from the Faculty of Sexual and Reproductive Healthcare (FSRH), formerly the Faculty of Family Planning and Reproductive Healthcare (FFPRHC), recommend 7 days' delay in onset of menstruation as the threshold for doing a pregnancy test [FFPRHC, 2006b]. However, the manufacturer of levonorgestrel recommends 5 days [ABPI Medicines Compendium, 2004a; ABPI Medicines Compendium, 2004b].
    • If the date of last menses is unknown, tests for pregnancy should not be done before 21 days have elapsed since unprotected sexual intercourse [FFPRHC, 2006b].
  • If the woman vomits soon after taking the levonorgestrel pill, she should take a second dose as soon possible.
  • The next menstrual period might be different [ABPI Medicines Compendium, 2004a; ABPI Medicines Compendium, 2004b].
    • If the woman has early mild bleeding or spotting, this is probably caused by the levonorgestrel and may not be the start of the next menstrual cycle. She should not regard this time as safe for unprotected sexual intercourse. In any case, no time is regarded as a completely safe time for unprotected sexual intercourse including time during menstruation.
    • Most women will have a normal period at the expected time; some women will have their period later or earlier than normal.
  • Levonorgestrel emergency contraception does not provide contraceptive cover for the remainder of the cycle; the woman should therefore use an effective contraceptive method or avoid sexual intercourse [FFPRHC, 2006b]:
    • She can be advised that levonorgestrel emergency contraception can be used more than once in a cycle if clinically indicated [FFPRHC, 2006b].
    • If she does not wish to use ongoing regular contraception, she can be offered advance provision of levonorgestrel to promote early use of emergency contraception [FFPRHC, 2006b].
  • Oral levonorgestrel emergency contraception does not cause abortion. If the woman is already pregnant, levonorgestrel will not work, but it should not harm her or the fetus.
  • Ongoing contraception (e.g. with an IUD or contraceptive pill) may be started at the same time or soon after levonorgestrel, provided that the UK Medical Eligibility Criteria are met [FFPRHC, 2006a] — see the CKS topic on Contraception.

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