| Abstract: | Abortion was successfully induced in 62 of 68 patients in the 9th to the 26th week of pregnancy be serial intramuscular administration of 15(S)-15-methyl-prostaglandin F2alpha (15-ME-PGF2alpha). In 6 patients who failed to abort after 24 hours of prostaglandin administration, a concomitant infusion of oxytocin was initiated; 5 of these patients aborted within 12 hours of the combined therapy. A single patient failed to abort, even with the combined therapy, and underwent surgical evacuation. The mean abortion time in the 67 successful inductions was 14.56 hours. Parous patients aborted somewhat fasteter, mean 13.98 hours, as compared to nulliparous patients, mean 15.02 hours, but this difference was not statistically significant. In this study initial intramuscular injection of 100 mug 15-ME-PGF2alpha was followed in 1 hour by 250 mug and then 250 mug every 2 hours with concomitant oxytocin therapy initiated after 24 hours. The results with this dose schedule were compared to the results obtained in a previous study with a higher dose schedule, an initial dose of 100 mug 15-ME-PGF2alpha, followed in 1 hour by 250 mug then 500 mug every 2 hours. There was significant difference in the mean abortion time and the incidence of side effects between the 2 dose schedules. The mean abortion time for patients with gestational ages 16 weeks and less was the same with both dose schedules, however patients with gestational ages of 17 weeks and higher aborted somewhat faster with the higher dose schedule. It might therefore be advisable for patients with gestations of 17 weeks and higher to be treated with the higher dose schedule. In earlier gestations patients could be started on the lower schedule, and if abortion had not occurred within 15 hours the dose of 15-ME-PGF2alpha could then be increased to 500 mug every 2 hours. |
