To compare the effectiveness of medicated γ intrauterine device (IUD) and medicated genefix IUD inserted immediately after abortion.A multicenter clinical trail was performed for the study from Mar. 2012 to Jan. 2013. Totally 840 women who volunteered to participate were randomly allocated to γ-group (medicated γ IUD) or genefix-group (medicated genefix IUD) immediately after abortion. While 464 abortion women who had not used IUD or steroids contraceptive methods were chosen as control group. The effectiveness of the IUD were followed up for 1 year. All women were required to record the number of vaginal bleeding days and blood volume of vaginal bleeding within 3 months after abortion.At the 12(th) month, the expulsion was the most common reason for termination. The expulsion rates of genefix-group and γ-group were 2.48/100 women years and 3.12/100 women years, respectively (P>0.05). For the expulsion reasons, IUD moving down could account for more than seventy percent. The removal rate for IUD usage of two IUD groups were almost equal (3.91/100 women years verus 4.35/100 women years), the differences were not statistically significant (P>0.05). At the 90(th) day after abortion, comparing with control group, the bleeding and (or) spotting days of genefix-group and γ-group extended by 3.9 and 2.6 days respectively, the differences had statistical significance between the three groups (P0.05).The insertion of medicated genefix IUD and medicated γ IUD immediately after abortion is safe, feasible, has slight side effects and could be effective contraception.