Abnormal concentrations of prostaglandins in amniotic fluid during delayed labour in multigravid patients

Summary. Concentrations of prostaglandins E (PGE), F_2α (PGF), 13,14-dihydro-15-keto prostaglandin F_2α (PGFM), 6-keto F_1α and thromboxane B₂ were measured by specific radioimmunoassay in samples of amniotic fluid from 22 multigravid patients during labour. Normal labour in 10 patients was associated with a significant increase of PGE, PGF and PGFM with close correlation to cervical dilatation ( P < 0.05). In the 12 patients with clinically delayed labour, in the absence of cephalopelvic disproportion, there were significantly lower PGF ( P <0.002) and PGFM ( P < 0.05) concentrations obtained while no differences were observed in the other prostanoids measured. Administration of oxytocin to the latter group to enhance labour did not have any effect on the concentrations of prostaglandins obtained in spite of an improvement in intrauterine pressures and accelerated progress of labour.