title: [Clinical experience with 7 years of norplant].
abstract: OBJECTIVE
  To assess the efficacy, safety of Norplant implants used by Chinese women.
  
  
  METHODS
  In a prospective, multicenter clinical trial, 10,718 women receiving Norplant implants were monitored annually through 5 years and part of women continuously used the implants up to 7 years.
  
  
  RESULTS
  The five-year pregnancy rate was 0.63/100 users. 7,554 women completed 5 years, 3,622 women completed 6 years and 2,433 women completed 7 years. The annual pregnancy rates were 0.40/100 users in both year 6 and year 7. The pregnancy rates increased with weight (P < 0.05) and decreased with age. The menstrual disturbances were common, also the main reason for discontinuation. Headache, dizziness and weight gain led to termination more frequently than did other adverse events apart from menstrual disturbances. The 5-year continuation rate was 72.1/100 users. Among aged > 30 and weight < 60 kg, the implants may be used for 7 years.
  
  
  CONCLUSIONS
  It's proved that the Norplant implants is a highly effective, long acting, safe, simple and reversible contraceptive method, and it is acceptable in Chinese women.
authors.affiliation: Beijing Municipal Research Institute of Family Planning in Beijing, Beijing 100006.
authors.forename: S
authors.initials: S
authors.lastname: Huang
authors.forename: S
authors.initials: S
authors.lastname: Gu
mesh_terms: D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage*; D003692:Delayed-Action Preparations; D004343:Drug Implants; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000009:adverse effects; D011446:Prospective Studies
chemical_list: D003271:Contraceptive Agents, Female; D003692:Delayed-Action Preparations; D004343:Drug Implants; D016912:Levonorgestrel