Coagulation and fibrinolysis changes in normal pregnancy increased levels of procoagulants and reduced levels of inhibitors during pregnancy induce a hypercoagulable state, combined with a reactive fibrinolysis

Objective: To establish the physiologic changes in the coagulation and fibrinolytic systems during normal pregnancy and puerperium. Study Design: One hundred and seventeen normal pregnant women were investigated in a longitudinal study involving five measurements: blood samples were collected at 10, 20, 30, 36 weeks and on the second day puerperium and were assayed for prothrombin time (PT expressed in INR), activated partial thromboplastin time (PLY), fibrinogen (FBG), antithrombin III activity (AT III), protein C activity (PC), protein S activity (PS), prothrombin fragments 1+2 (F1 +2), type 1 plasminogen activator inhibitor activity (PAI) and tissue-plasminogen activator antigen (t-PA). Student t-test, One Way Analysis of Variance (ANOVA) and Bonferroni test were used for statistical analysis. P