Changes in the blood coagulation and fibrinolysis system in the course of normal pregnancy
Justus, B.; Siegert, G.; Tiebel, O.
Zentralblatt für Gynakologie 114(4): 165-170
1992
ISSN/ISBN: 0044-4197 PMID: 1621453 Document Number: 392163
In the present study we investigated several factors of hemostasis and fibrinolysis during the normal pregnancy in 52 women. Whereas the Thrombin-Time did not show any change, the increase of the Hepato-Quick and the decrease of the Partial Thromboplastin-Time was significant. During pregnancy we observed a significant increase of the activity of fibrinogen, factor XII and prekallikrein as well as of the von-Willebrand-factor-antigen (VIIIR:Ag). The activity of factor II and X remained constantly. The increased activity of factors of hemostasis was accompanied by an increase of activity and concentration of antithrombin-III. In contrast to the activity of the hemostatic system we could not find any significant alteration of the fibrinolytic system. The cause must be searched in the observed increase of plasminogen-activator-inhibitor (PAI)--likly in combination with a decrease of the tissue-type plasminogen activator (t-PA). Our data indicate, that the highest risk for thrombosis already might exist in week 24 of pregnancy, because a distinct increase of hemostatic activity is combined with a nearly unchanged fibrinolytic activity.