A multicenter clinical comparative study of domestically produced implant contraceptive No. I and No. II with Norplant (Three years' follow-up)

Objective: To compare the efficacy, side-effects and acceptability of domestic produced implant No. I and No. II with Norplant. Method: A multicentered randomized prospective clinical trial was conducted in ten centers in Chi na since 1993. Every center have recruited 100 cases for each of the three types of implants. Results: Altogether l, 001 cases of No. I, 1, 000 cases of No. II and 998 cases of Norplant were recruited. The follow--up rate was 99. 2% at the end of 24 months and 99. 1% at the end of 36 months. One pregnancy in No. I implant occurred & months after insertion and the net cumulative pregnancy rate was 0. 1 per 100 women. Total discontinuation rates were 15. 1, 14. 1, and 12. 9 per 100 women in NO. I, No. II and Norplant groups respectively. Among them about 75% of discontinuation was due to the menstrual problems. The incidence of side-effects were 22. 6%, 19. 0% and 19. 7% respectively at 36 months follow--up. There was no significant differences in efficacy and side effects among these three types of implant. Conclusion: The result of this three-years’ follow--up indicated that the domestic products implant No. I and No. II just as Norplant are long term, highly effective contraceptive and have been accepted in different area by different people. It will be widely selected by women of reproductive age in China.