Endogenous prostaglandin level in the amniotic fluid in premature labor

: Radioimmunological determinations of prostaglandin (PG) levels have been performed in amniotic fluid samples from 53 patients with signs of premature labour in order to characterize the significance of the PG system for the initiation and progress of preterm deliveries compared with term deliveries. Statistically not significant slightly increased levels of both PG E- and PG F-equivalents during premature labour were observed when compared with undisturbed pregnancies of the same gestational age, but never reached concentrations characteristic for term pregnancies without uterine contractions. Patients, in whom premature labour could not be prevented exhibited elevated PG levels parallel to cervical dilatation during the course of parturition remaining, however, pronounced below that detected at comparable cervical state and duration of labour during term deliveries. It is concluded that at the gestational age of preterm labour the PG producing system is still immature, rendering the PG cascade to a minor functional role than during spontaneous term labour. A prognostic value of PG determinations and indications for a causal treatment of premature labour with PG synthesis inhibitors are not supported by the present investigations.