Contraceptive effectiveness of two insertions of quinacrine: results from 10-year follow-up in Vietnam.

BACKGROUND: This study was conducted to evaluate the long-term effectiveness of two insertions of quinacrine pellets for nonsurgical sterilization among women in northern Vietnam. STUDY DESIGN: Observational cohort study of 1335 women who received two quinacrine insertions between 1989 and 1993. RESULTS: About 90% of the study population participated in the last round of interviews. Cumulative follow-up time for this cohort was 14,294 person-years. The 1-, 5- and 10-year cumulative pregnancy probabilities for quinacrine were 3.3% (95% CI, 2.4-4.3), 10.0% (95% CI, 8.4-11.6) and 12.1% (95% CI, 10.4-13.9), respectively. Pregnancy estimates with quinacrine in this cohort were higher than that reported from US-based research on surgical tubal sterilization and higher than results of quinacrine sterilization in Chile. Quinacrine effectiveness was better among older women. CONCLUSION: The effectiveness of quinacrine in Vietnam was lower than other forms of sterilization. Factors such as inconsistent training and use of various insertion techniques may have contributed to the relatively high failure rate.

Safety of quinacrine contraceptive pellets: results from 10-year follow-up in Vietnam.

BACKGROUND: This study was conducted to evaluate long-term safety of quinacrine pellets for nonsurgical sterilization among women in Vietnam. STUDY DESIGN: Observational cohort study of 2735 women who had quinacrine insertions between 1989 and 1993 compared to 1623 women who received an intrauterine device (IUD). RESULTS: Cumulative follow-up times for the quinacrine and IUD cohorts were 28,697 and 17,382 person-years, respectively, and losses to follow-up were 6% and 7%, respectively. Quinacrine users had a higher incidence of ectopic pregnancy compared to IUD users (risk ratio, 2.2; 95% confidence interval, 1.06-4.54); the risks of cancer, hysterectomy, pelvic/gynecologic surgery and death were similar in the two groups. Two quinacrine insertions appeared to lower the risk of ectopic pregnancy to that of surgical tubal occlusion. CONCLUSIONS: Use of quinacrine in this cohort appeared to have minimal health risks. Other research, including preclinical studies, needs to be considered in an overall evaluation of whether the combination of safety and efficacy provide a basis for quinacrine's approval by appropriate regulatory agencies.