Release of tissue plasminogen activator during and after delivery

In late pregnancy and during delivery, blood fibrinolytic activity significantly changes. Those changes may be caused by changed levels of oxytocin and prolactin during 
and after delivery. Changes in oxytocin and
 prolactin levels and in individual components of
fibrinolytic system were determined in blood of 
fifteen women, who had vaginal delivery (group
 V) and in fifteen women, who delivered by caesarean section (group C). Fibrinolytic parameters (unspecific fibrinolytic activity, activity and
 antigen of tissue plasminogen activator, activity
 of inhibitor of plasminogen activator and antigen of endothelial inhibitor of plasminogen activator) and hormones were determined before
 delivery, during the first stage of delivery, one
 hour after delivery of placenta, and three and 
ten days after delivery. Prior to, and three and 
ten days after delivery, fibrinolytic parameters 
were determined also after stimulation by venous occlusion. No significant differences between the two groups were found. Correlations 
between fibrinolytic parameters and hormones
 were not significant either. Response to venous occlusion measured by some fibrinolytic parameters changed significantly after delivery,
though, the differences between groups were
 not significant. It was concluded that stress due
 to vaginal delivery was similar to stress after 
caesarean section concerning most fibrinolytic 
parameters. The two hormones measured, probably have no affect on fibrinolysis during 
and after delivery.