What factors should determine the type of emergency postcoital contraception chosen?
If less than 120 hours have passed since sexual intercourse occurred either one of the hormonal methods can be used. After 120 hours there is an increase in failure if the Yuzpe method or Plan B is used. This does not mean that hormonal methods are absolutely contraindicated after 120 hours. If the woman presents later than 120 hours but before seven days, and will not accept the intrauterine contraceptive device (IUCD), one of the hormonal mechanisms can be given provided that the woman is aware of the increased failure rate. After 5 days, however, the IUCD is the less likely to result in failure than the Yuzpe or Plan B method. If the IUCD is to be used the woman should be preferably an otherwise good candidate for the IUCD.(see question on patient selection for the IUCD).
