Both the Filshie clip and tubal ring were effective and safe for interval tubal sterilization

OBJECTIVE To compare the efficacy and safety of two methods of tubal sterilization, the tubal ring and the Filshie clip, applied via minilaparotomy or laparoscopy. DESIGN Two multicentre, randomized, assessor-blind, controlled trials. Allocation was computer-generated and stratified by centre, using sealed envelopes. The study had sufficient power to detect an absolute difference of 8/1000 in pregnancy rate. SETTING Twelve hospitals in Mexico, Panama, Dominican Republic, Peru, Brazil, Kenya, Indonesia, and Thailand. SUBJECTS 2746 healthy women, aged 21 years or older (mean 31 years), who requested sterilization, had a normal pelvic examination, and had not been pregnant in the previous 7 weeks. Mean parity was 3.7. INTERVENTION The procedures were carried out by minilaparotomy in 915 subjects in five centres and by laparoscopy in 1831 subjects in seven centres. In the former study, 462 women were randomized to receive the Filshie clip and 453 to receive the tubal ring. In the latter study, 919 women were randomized to receive the Filshie clip and 912 to receive the tubal ring. Follow-up was done at 1, 6, and 12 months. MAIN OUTCOME MEASURES Pregnancy within 12 months, intraoperative and postoperative complications. MAIN RESULTS Excluded from the analysis were 13 women who did not receive either occlusion device and nine women who were already pregnant at the time of surgery. 3% of women (similar in each group) received the alternative device to the one assigned and were analysed by device received. 18% of women (similar in each group) were lost to follow-up. Two women in each group became pregnant within 12 months of surgery (all in the laparoscopy study). The 12-month cumulative pregnancy rate by life table analysis for the two studies combined was 1.7 per 1000 treated women (SE 1.3) with both methods (P = 0.98). There was no case of ectopic pregnancy. The proportion of women with surgical injury was 5.8% with the Filshie clip and 9.0% with the tubal ring (P = 0.08) in the minilaparotomy study and 1.3 and 3.2%, respectively, (P = 0.01) in the laparoscopy study. After 1 month, there was no significant difference between treatment groups, in either study, for rates of primary incision complications (14% with minilaparotomy, 4-5% with laparoscopy), infection (<1% in both studies), or other major complications (1-2% with minilaparotomy, 1% with laparoscopy). CONCLUSION Both the Filshie clip and the tubal ring were effective and safe for interval tubal sterilization, with 12-month pregnancy rates of less than 2/1000 and low complication rates. Surgical injury was less frequent with the Filshie clip.