MULTICENTERED, PHASE-III CLINICAL-TRIAL OF NORETHISTERONE ENANTHATE 50-MG PLUS ESTRADIOL VALERATE 5-MG AS A MONTHLY INJECTABLE CONTRACEPTIVE - FINAL 3-YEAR REPORT

Norethisterone enanthate (NET-EN) 50 mg combined with estradiol valera te (EV) 5 mg was studied as a once-a-month iniectable contraceptive wi th regard to effectiveness, cycle control, adverse events and acceptab ility. In eight Family Planning Centres from five Latin American count ries, 931 fertile women were followed-up for a period of 36 months, pr oviding a total of 15,787 woman-months of experience. Only one pregnan cy occurred: in the first treated month a few days before the second i njection (failure rate 0.08 per 100 woman-years). Under treatment, the first cycle was drastically shortened in most cases, but thereafter c ycles tended to recover to pre-treatment patterns. There was a signifi cant decrease of hypermenorrhoea and dysmenorrheic cycles. Intracyclic bleeding and spotting appeared in 1.8% and 2.2%, respectively, and am enorrhea in 2.8% of cycles. The incidence of other adverse events was very low with the exception of weight gain of more than 2 kg (36.8%). The continuation rate at 12 months was 64.7%, at 24 months 31.0% and a t 36 months 20.4%. The cumulative discontinuation rate due to bleeding problems was 6.1% and 7.2% due to adverse events at 36 months. The tr eatment was shown to be a highly effective contraceptive method that o ffers fairly good cycle control, good tolerance and a continuation rat e that makes it suitable for use in family planning programmes in the Latin American area.