Blood Coagulation and Fibrinolysis During Normal Pregnancy

Abstract

Summary: Fifty-six pregnant women (gestational age 6-40 weeks) were evaluated for their coagulation activation (fibrin monomers and thrombin-antithrombin III complex) and for their fibrinolysis profile by determining tissue plasminogen activator, plasminogen activator inhibitor, plasminogen, a 2 -antiplasmin-and D-dimer. Fibrin monomers and thrombin-antithrombin III complexes were found to be significantly increasing with gestational age. All the fibrinolytic parameters showed a steady growth with the progress of the pregnancy, with the exception of tissue plasminogen activator which showed a significant decrease with gestational age, but mainly within the reference ränge. These results suggest a Stimulation of the coagulation System and an activation of fibrinolysis with ongoing pregnancy, although the increasing oc 2 -antiplasmin and plasminogen levels and the decreasing tissue plasminogen activator concentrations do not conform to this trend.

Cell-Free mRNA Concentrations of Plasminogen Activator Inhibitor-1 and Tissue-Type Plasminogen Activator Are Increased in the Plasma of Pregnant Women with Preeclampsia

“…In contrast, other authors have reported no significant increase in plasma PAI-1 in preeclampsia during late gestation or in cases of intrauterine growth retardation (18,19 ). Similarly, some authors report significantly increased tPA concentrations within the plasma of women with preeclampsia (14,16,18 ), whereas others refute these findings (16,20 ). We theorize that the PAI-1 and PA system may play a critical role in the pathogenesis of preeclampsia in early pregnancy and that mRNA expression of PAI-1 and tPA might reflect physiological alterations that occur later in pregnant women with preeclampsia.…”

Correlation between Grade III Placenta and Plasma Antithrombin III Activity in Full Term Pregnancy

“…Pregnancy is associated with blood hypercoagulability, and hypercoagulation is even more pronounced during the third trimester [2,8]. According to Kara et al [5], echogenic areas of grade III placentas are histologically equivalent to a fibrinous layer, thus suggesting the presence of intervillous thrombosis.…”

D-Dimer Concentrations in Normal Pregnancy: New Diagnostic Thresholds Are Needed

“…Normal pregnancy causes the maternal plasma D-dimer concentration to increase progressively from conception until delivery (1)(2)(3)(4)(5)(6)(7)(8)(9)(10). This increase confounds the use of the D-dimer to rule out suspected venous thromboembolism in symptomatic pregnant patients.…”