Phase III clinical trial with Norplant II (two covered rods): report on five years of use.

The subdermal implant NORPLANT II contraceptive was studied for its safety, efficacy and acceptability over a period of 5 years of use in a phase III multicentre clinical trial. A total of 1,466 women were observed for 52,849 women-months of use. Only four pregnancies were reported during the study period, giving a method failure rate of 0.8 per 100 users at 5 years of use. The continuation rates were 61.4, 49.0 and 42.1 per 100 users at 3, 4 and 5 years of use, respectively. The majority of the discontinuations were due to bleeding irregularities which accounted for 22.2, 26.3 and 28.5 per 100 users at 3, 4 and 5 years of use, respectively. The next common reason was planning pregnancy which was observed mainly in women having one child. The discontinuations due to infection, expulsion or displacement of device were very low (0.2-0.3 per 100 users). Due to vigorous efforts made by the centers to follow the subjects, the lost-to-follow-up rate was very low (1.6% at 5 yr).