Range of interventions effective for emergency contraception

Levonorgestrel and mid‐dose mifepristone (25–50mg) were more effective than the Yuzpe regimen (oestradiol–levonorgestrel combination). Both mid‐dose (25–50mg) and low‐dose mifepristone (<25mg) were probably more effective than levonorgestrel (1.5mg). Low‐dose mifepristone (<25mg) was less effective than mid‐dose mifepristone. Ulipristal acetate may be more effective than levonorgestrel.

Levonorgestrel users had fewer side effects than Yuzpe users and appeared to be more likely to have menses return before the expected date. UPA users were probably more likely to have menses return after the expected date. Menstrual delay was probably the main adverse effect of mifepristone and seemed to be dose related. Copper intrauterine devices may be associated with higher risks of abdominal pain than emergency contraceptive pills.