Mifepristone was more effective than the Yuzpe regimen for emergency contraception.

Patients 1000 women between 16 and 45 years of age seeking emergency contraception within 72 hours after an episode of unprotected sexual intercourse who had regular menstrual cycles (21–35 d), were certain about the dates of their last menstrual period, and were willing to abstain from further acts of unprotected intercourse during the menstrual cycle. Exclusion criteria were use of oral contraceptives or hepatic enzyme inducing drugs, chronic adrenal failure, long term corticosteroid treatment, breast feeding, allergy, or contraindications to mifepristone or to oestrogen and progestogen. Women certain to continue with pregnancy if emergency contraception failed were also excluded. 958 women (96%) (mean age 22.5 y) had complete follow up.