Prostaglandin F2alpha disappearance and concentration in amniotic fluid and blood of women undergoing abortion with intra-amniotic hypertonic saline

Human decidua and uterine contractility

Physiological saline solution injected into the uterus by the extraamniotic route was found to damage the decidua and rupture its lysosomes. The mechanism by which this procedure provokes abortion may be through the release of lysosomal phospholipase A2 (EC 3.1.1.4), an enzyme thought to regulate the formation of polyunsaturated fatty acids utilized for prostaglandin synthesis. A similar sequence of events may be involved in the initiation of spontaneous labour, since decidual cells obtained at elective Caesarean section at term exhibited degenerative changes and signs of release of a lysosomal marker enzyme. The cause of this release is unknown.

Serum hormone levels in women undergoing abortion with intra-amniotic, extra-amniotic or intra-muscular administration of 15(S) 15-methyl-prostaglandin F2alpha

The serum levels of estradiol-17beta, progesterone and HPL have been estimated by specific radioimmunoassay in thirty women undergoing abortion with 15-methyl-PGF2alpha given by intra-amniotic, extra-amniotic or intra-muscular route. A significant decline in the levels of these hormones was observed in 27 cases in which the pregnancy was terminated. However, in the remaining three cases, 15-methyl-PGF2alpha was found to be unsuccessful, and no significant change in the hormone levels was evident. The decline in these hormones was more marked by intra-muscular route, than that observed by the other routes. The pattern of estradiol-17beta decline was more consistent when compared with progesterone and HPL. The levels of progesterone and HPL, in a few cases, rather showed an increase in the initial hours of 15-methyl-PGF2alpha administration before the decline began and this pattern was more prominent on extra-amniotic administration. In general, the decline in the hormone levels was slower in cases which took longer time for abortion than cases with shorter induction-abortion time (IAT). The decline in estradiol-17beta levels was about 65% at six hour of intra-muscular administration of 15-methyl-PGF2alpha, whereas the corresponding fall with intra-amniotic and extra-amniotic routes was 29 and 22%, respectively. However, the net drop in its levels during IAT was not significantly different (range 70 to 80%) by the three routes. About 38% fall in progesterone levels was observed at six hour of intra-muscular administration whereas, by intra-amniotic the fall was 19%. The net decline in progesterone levels, during IAT, was in the range of 46 to 60% by the three routes. Similarly, intra-muscular 15-methyl-PGF2alpha evoked a sharper decline in HPL levels as compared with other routes. The total decline during IAT was 58 to 66%. The results, thus indicated that the abortion with 15-methyl-PGF2alpha was associated with a fall in the serum hormone levels, which could be resultant effect of alterations in the hormone production by the foeto-placental unit. This along with the uterine contractions may play a significant role in the abortifacient action of 15-methyl-PGF2alpha.