Fibrinolytic activity during pregnancy.

It has been a general concept that fibrinolytic activity is diminished during pregnancy. However, increase in FDP (fibrin/fibrinogen degradation products by plasmin digestion) which indicates accelerated fibrinolytic activity is also observed during pregnancy. To clarify these conflicting findings, alpha-2-plasmin inhibitor and FDP, sensitive indicators of fibrinolytic activity, were studied during pregnancy. Decrease in plasmin inhibitor and increase in FDP were found during pregnancy suggesting that fibrinolytic activity is accelerated during pregnancy. Since FDP level was higher in blood samples from the uterine vein than those from the artery, the accelerated fibrinolysis characterized by decrease in plasmin inhibitor and increased FDP, might be reflection of local event. On the other hand, systemic blood remains still hypofibrinolytic in normal pregnant condition.