Vaginally administered 16, 16-dimethyl-PGE2 for the induction of midtrimester abortion.

Thirty patients in the 13th-20th week of gestation underwent therapeutic abortion utilizing vaginally administered 16, 16-dimethyl-PGE2 (free acid) suppositories. The first 15 patients obtained individual doses in the range of 400-1200 mug given every three hours (mean total dose 4.2 mg). In the following 15 patients a fixed dose schedule was used (800 mug followed by 1000 mug every three hours; mean total dose 5.3 mg). All but one of the 30 patients aborted. The mean induction-abortion interval for all patients was 16.8 +/- 6.9 hours (mean +/- S.D.) With the fixed dose regime the success rate was 100% and the induction-abortion interval 16.0 +/- 5.9 hours. Because gastro-intestinal side effects were minimal, neither anti-emetic nor anti-diarrheic medication was required. A slight elevation of temperature was noted in five patients. The uterine response to the vaginal administration of this compound was characterized by a gradual increase in uterine tonus followed by sustained stimulation. The results are interpreted to suggest that the vaginal administration of 16, 16-dimethyl-PGE2 is a useful alternate method for the induction of second trimester abortion. Moreover, this compound seems to cause fewer gastro-intestinal side effects than other prostaglandins administered by the vaginal route at our department.