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Selected Practice Recommendations for Contraceptive Use

Second edition



20. What can a woman do to prevent nausea and vomiting when taking emergency contraceptive pills (ECPs)?

  • Levonorgestrel-only ECPs are preferable to combined estrogen-progestogen ECPs because they cause less nausea and vomiting.
  • Routine use of anti-emetics before taking ECPs is not recommended. Pretreatment with certain anti-emetics can be considered depending on availability and clinical judgement.




The expert Working Group considered that many women will not experience nausea or vomiting when taking ECPs and that it is difficult to predict which women will experience nausea or vomiting. Although the expert Working Group did not recommend routine use of anti-emetics before taking ECPs, it noted that anti-emetics are effective in some women and can be offered when appropriate.

When providers are deciding whether to offer anti-emetics to women taking ECPs, they should consider the following:

  • Nausea and vomiting are more likely to occur in women taking combined estrogen-progestogen ECPs than in women taking levonorgestrel-only ECPs.
  • Evidence indicates that anti-emetics reduce the occurrence of nausea and vomiting in women taking combined estrogen-progestogen ECPs.
  • Women who take anti-emetics may experience other side-effects from the anti-emetics.
  • In some settings, availability of anti-emetics may be constrained.

From the limited evidence that the expert Working Group considered, it could not be established whether taking ECPs with food alters the risk of nausea or vomiting.


Systematic review question

What is the evidence regarding prevention of nausea and vomiting among women who take ECPs?
Level of evidence: I, good, direct.


References from systematic review

1. Anonymous. Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Task Force on Postovulatory Methods of Fertility Regulation. Lancet, 1998, 352:428–433.

2. Arowojolu AO, Okewole IA, Adekunle AO. Comparative evaluation of the effectiveness and safety of two regimens of levonorgestrel for emergency contraception in Nigerians. Contraception, 2002, 66:269–273.

3. Ellertson C et al. Modifying the Yuzpe regimen of emergency contraception: a multicenter randomized controlled trial. Obstetrics and Gynecology, 2003, 101:1160‑1167.

4. Ho PC, Kwan MS. A prospective randomized comparison of levonorgestrel with the Yuzpe regimen in post-coital contraception. Human Reproduction, 1993, 8:389–392.

5. Ragan RE, Rock RW, Buck HW. Metoclopramide pretreatment attenuates emergency contraceptive-associated nausea. American Journal of Obstetrics and Gynecology, 2003, 188:330–333.

6. Raymond EG et al. Meclizine for prevention of nausea associated with use of emergency contraceptive pills: a randomized trial. Obstetrics and Gynecology, 2000, 95:271–277.

7. Shochet T et al. Side effects of the Yuzpe regimen of emergency contraceptive pills and two modifications. Contraception, 2004, 69:301–307.

8. von Hertzen H et al. Low dose mifepristone and two regimens of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Lancet, 2002, 360:1803–1810.


Key unresolved issues

What are the most effective regimens for preventing and treating nausea and vomiting associated with ECP use?

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