Clinical Observation of the Efficacy of Mifepristone and Levonorgestrel on the Emergency Contraception

Objective:To study the lowerest does of mifepristone on the emergency contraception.Methods:200 healthy women with history of unprotect intercourse or contraception failure were recruited. All attended the study within 72 hours after intercourse.A single dose of mifeprstone(1 tablet,10 mg/tab)was given to the 100 cases.Levonorgestrel (1 tablet 0.75 mg/tab)was given and the same dose was repeated 12 hours later to the other 100 cases.The successful standard was the flowing of menstruation.The Dixon method was used for calculating the contraceptive effective rates.Resulte:There was one case of pregnancy in the mifepristone group and there were 2pregnancies in the levonorgestred group,which were far fewer than we expected with significant difference of 9.916 and 10.603 respertively ( P 0.01).The contraception effective rates were 89.92%(mfepristone)and 81.14%(levonorgestrel).There was no significant difference between these two groups ( P 0.05).The side effects including nausea and vomiting or menstruous alteration in the mifepristone gronp were milder than those in the leronorgestred group.A single dose of mifepristone (10 mg/tab) was coveniently and easily accepted by the women.Conclusions:Mifepristone tablet (10 mg/tab) was effective,safe and simple for emergency contraception.