Prostaglandins in the plasma and amniotic fluid of rhesus monkeys during pregnancy and after intra-uterine foetal death.

Prostaglandin F (PGF) was measured in amniotic fluid, and 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) was measured in maternal peripheral venous plasma and amniotic fluid of rhesus monkeys during late pregnancy. 13,14-Dihydro-15-keto-PGF2 alpha was determined in the maternal peripheral venous plasma of two animals following intra-uterine foetal death. The mean concentration of PGF and PGFM in amniotic fluid increased fourfold during the last 5 days of pregnancy. This increase was associated with an increase in the oestrone concentration in amniotic fluid and in maternal plasma. In normal pregnancy there was no increase in PGFM levels in the maternal peripheral vein, up to 1-2 days pre partum. After intra-uterine death, progesterone concentration in the maternal peripheral vein was unaltered, but oestrone and oestradiol declined. In plasma samples taken within 12 h of delivery, the concentration of PGFM was raised. It is concluded that an increase in prostaglandin production accompanies delivery at normal term, and at delivery past term following intra-uterine foetal death.