Multinational comparative clinical trial of long acting injectable contraceptives norethisterone enanthate given in 2 dosage regimens and depot medroxy progesterone acetate
Who
Contraception 25(1): 1-12
1982
ISSN/ISBN: 0010-7824 Document Number: 562690
A multicenter phase III clinical trial was undertaken to compare norethisterone enantate (NET-EN) given by 2 different treatment regimens and depot-medroxyprogesterone acetate (DPMA). After 18 mo. of observation, preliminary findings are reported for 1589 women who received DMPA 150 mg every 90 days; 790 women who received NET-EN 200 mg every 60 days; and 796 women who received NET-EN 200mg every 60 days for 6 mo., then 200 mg every 84 days. The overall discontinuation rates per 100 women were similar for all 3 treatment groups over the 18 mo. observation (61.8-63.5/100 women). The discontinuation rates for bleeding problems and for personal reasons were also similar for all 3 treatment groups. However, terminations due to amenorrhea were significantly higher among DMPA users (12.1 and 17.4/100 women at 12 and 18 mo.) as compared with both NET-EN groups (6.8-8.2/100 women at 12 mo. and 10.4-10.9/100 women at 18 mo.). The only significant difference in pregnancy rates observed between the 3 groups was a higher rate at 18 mo. among NET-EN (84 days) users (1.6/100 women), as compared with DMPA users (0.2/100 women). There was no overall significant difference between the 2 NET-EN groups, although between the 6 and 18 mo. follow-up when the 2 NET-EN regimens diverged, the NET-EN (84 days) users' pregnancy rate rose significantly, whereas in the NET-EN (60 days) group the pregnancy rate did not change. There was a significantly higher weight gain in those subjects using NET-EN at 60 day intervals compared with those using it at 84 day intervals.