Midtrimester abortion induced by single intra-amniotic instillation of two dose schedules of 15(S)-15-methyl-prostaglandin F2alpha

Abstract

Midtrimester abortion was successfully induced in a series of 20 patient by intraamniotic instillation of 15(S)-15-methyl-prostaglandin F2alpha with a mean abortion time of 17.78 hours. The patients in this study was divided into two groups, Groups 1 received an initial dose of 2.5 mg 15-ME-PGF2alpha and aborted in a mean time of 16.26 hours. The patients in Group II received 3.0 mg 15-ME-PGF2alpha and aborted in a mean time of 18.94 hours. There was no significant difference in the abortion time, occurrence of side effects or the initiation of uterine activity between Group I and Group II. Parous patients aborted somewhat faster than nulliparous patients but this difference was not significant. In this study 80% of the patients aborted in 24 hours or less, and the intra-amniotic instillation of 15-ME-PGF2alpha was an effective abortifacient technique from the 15th to the 23rd week of gestation. The uterine response to intra-amniotic instillation of 15-ME-PGF2alpha was characterized by the gradual appearance of low amplitude, high frequency contractions accompanied by a rise in baseline intrauterine tonus. Uterine activity developed gradually and peaked at 1:50 hours after intraamniotic instillation of 15-ME-PGF2alpha. In this small series 15-ME-PGF2alpha administered via intra-amniotic instillation did not appear to have a distinct advantage over the naturally occuring PGF2alpha administered by the same method for the induction of midtrimester abortion; a large series in indicated to define the advantage of either technique.

PIP: Midtrimester abortion was successfully induced in a series of 20 patients by intramniotic instillation of 15(S)-15-methyl-prostaglandin (PGF) F2alpha with a mean abortion time of 17.78 hours. The patients in this study were divided into 2 groups. Group 1 received an initial dose of 2.5 mg 15-ME-PGF2alpha and aborted in a mean time of 16.26 hours. The patients in Group 2 received 3.0 mg 15-ME-PGF2alpha and aborted in a mean time of 18.94 hours. There was no significant difference in the abortion time, occurrence of side effects, or the initiation of uterine activity between Group 1 and Group 2. Parous patients aborted somewhat faster than nulliparous patients but this difference was not significant. In this study 80% of the patients aborted in 24 hours or less, and the intraamniotic instillation of 15-ME-PGF2alpha was an effective abortifacient technique from the 15th-23rd week of gestation. The uterine response to intraamniotic instillation of 15-ME-PGF2alpha was characterized by the gradual appearance of low amplitude, high frequency contractions accompanied by a rise in baseline intrauterine tonus. Uterine activity developed gradually and peaked at 1.50 hours after intraamniotic instillation of 15-ME-PGF2alpha. In this small series 15-ME-PGF2alpha administered via intraamniotic instillation did not appear to have a distinct advantage over the naturally occurring PGF2alpha administered by the same method for the induction of midtrimester abortion; a larger series is indicated to define the advantages of either technique.