RT Journal Article SR Electronic T1 10 mg of mifepristone prevented pregnancy as effectively as 600 mg within 5 days of unprotected intercourse JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 148 OP 148 DO 10.1136/ebm.1999.4.148 VO 4 IS 5 YR 1999 UL http://ebm.bmj.com/content/4/5/148.abstract AB