Amniotic fluid prostaglandins do not reflect human fetal lung maturation

Summary. Experimental data suggest the involvement of classic prostaglandins (PG), prostacyclin (PGI,) and thromboxane A₂ (Tx A₂ ) in fetal pulmonary development. To explore this possibility in man, we assayed serial amniotic fluid samples from 33 women for 13, 14 -dihydro-15-keto-PGF_2α (M-PGF_2α a metabolite of PGF_2α), 6-keto-PGF_1α (a breakdown product of prostacyclin (PGI₂)), and thromboxane B₂ (a metabolite of TxA₂) as well as for the lecithin/sphingomyelin (L/S) ratio and phosphatidylglycerol. No difference in these prostanoids was seen between the samples with the immature (< 2) or mature 2) L/S ratio, or between the samples with undetectable or detectable phosphatidylglycerol. The L/S ratio matured in 16 women and phosphatidylglycerol became detectable in 19 women during serial smpling, but even in these women the changes in the amniotic fluid prostanoids were inconsistent. It is concluded that the amniotic fluid M-PGF_2α, 6-keto-PGF_1α, and TxB₂ do not reflect fetal pulmonary maturity.