In the late cohort , dilation and evacuation procedures were less difficult after mifepristone ( 4.1 % , 95 % confidence interval [ CI ] 0.0-9 .6 ) than misoprostol ( 18.8 % , 95 % CI 7.7-29 .8 ) or dilators alone ( 18.8 % , 95 % CI 7.7-29 .8 ; P = .04 ) .