when is prostaglandins released in pregnancy
1 Prostaglandin production is increased at the time of labor (but not before). 2  Peripheral plasma levels of PGF 2Î± metabolite (PGFM) and TXB 2 increase during labor in women and monkeys, , , , , as do amniotic fluid concentrations of PGFM, PGE 2, PGF 2Î±, 6-keto-PGF 1Î±, TX, and arachidonate.