A two-year study of acceptability, side effects, and effectiveness of Norplant and Norplant-2 implants in the People's Republic of China.

A large scale, phased investigation of NORPLANT contraceptive systems was conducted in the People's Republic of China. The first phase comprehended 1,200 women in four cities. Expanded trials included 11,918 women at 12 major centers and at sub-centers by 31 May 1987. At that date 4,676 NORPLANT capsule subjects and 1,089 rod subjects had completed one year of use, 1,381 capsule acceptors had completed two years as had 197 rod users. Gross pregnancy rates were less than 0.1 per 100 for each implant type both at one and at two years. Continuation rates were 94 per 100 for each implant type at one year, and were 82.0 and 83.6 per 100 among users of NORPLANT capsule and rod implants, respectively, at two years. Disruption of menstrual function was the dominant reason for termination, but mean hemoglobin levels increased in each of the nine centers reporting values at admission and at one year. First year gross cumulative termination rates for medical reasons were 1.2 to 1.3 per 100, reaching 3.8 and 5.6 per 100 for capsule and rod implants, respectively, at two years. Microdose contraception with these levonorgestrel-releasing implants appears to be a highly acceptable and effective modality suitable for Chinese women. NORPLANT implants are now approved by the national drug regulatory agency for general use in China.