Effect of oxytocics on prostaglandin levels in the third stage of labour.

The levels of prostaglandin F2 alpha metabolites (PGFM) in the peripheral blood were measured during third stage in a group of patients not given any oxytocic and this was compared with the levels produced in other groups given different oxytocics. There was a significant rise in PGFM within 5 min of delivery in all groups but there was no statistical difference in the serum concentrations of PGFM between the different groups. This suggests that oxytocics given during third stage do not act through release of prostaglandins.