In a phase III multicentre clinical trial, the subdermal implant NorplantR-2 was studied for its clinical use effectiveness, safety and bleeding pattern. A total of 1466 healthy volunteers, with no contraindication to steroid use, were observed for 29,669 woman-months of use. One method failure was reported at 18 months of NorplantR-2 use. The method was associated with altered menstrual pattern with a trend towards reduced blood loss. The continuation rates were 88.1 and 73.5 per 100 users at 12 and 24 months of use, respectively. Menstrual disturbance, mainly prolonged bleeding, accounted for the majority of the discontinuations. Removal of NorplantR-2 due to local infection was rare (0.4 per 100 users at 24 months). In similar clinical trial conditions, the continuation rate with NorplantR-2 is significantly higher than those observed with LNG IUD and injectable contraceptives, norethisterone oenanthate 200 mg given every 60 +/- 5 days, and is comparable to that of CuT 200 IUD.