Background: Induced abortion is the medical or surgical termination of pregnancy before fetal viability. It has maternal or fetal indications. The aim of the present study was to evaluate the efficacy of the combination of methotrexate and misoprostol for termination of the pregnancy in the first trimester. Methods: This analytic study was performed on 100 women at the first trimester of pregnancy (<14th week), during 2004-2006. Each woman received intramuscular methotrexate (50 mg/m2) and intravaginal misoprostol (800 μg) 72 hours after methotrexate administration. The second dose of misoprostol was administered if abortion did not occur after 24 hours. Abdominal ultrasonography was performed 7 days after abortion. Results: Of the 100 women, 76 had gestational age >9 weeks and 24 has gestational age<9 weeks. Eighty one women (81%) had successful medical abortion and 19% women required curettage. Fifty nine patients with gestational age>9 weeks and 22 patients with gestational age <9 weeks had complete abortion. Failure rate was higher in missed abortion. Required dose of misoprostol and duration of conceptus expulsion were higher in pregnancies with missed abortion. Conclusion: Combination therapy with methotrexate and misoprostol represents a safe and effective alternative to invasive methods for termination of the pregnancy in the first trimester.