LEVELS OF COAGULATION INHIBITORS AND THROMBIN-ANTITHROMBIN-III COMPLEXES IN NORMAL-PREGNANCY

We evaluated changes in plasma coagulation inhibitors and thrombin-ant ithrombin III complexes in 60 normal pregnant women. Blood samples wer e taken on the first, second and third trimesters, during delivery and 3 days after delivery. Antithrombin III, thrombin-antithrombin III, h eparin cofactor II, protein C and protein S were determined using comm ercial tests. Antithrombin III remained unchanged during pregnancy, bu t increased after delivery. Heparin cofactor II levels during pregnanc y were above non-pregnant values, but returned to normal non-pregnant values at delivery. Protein C decreased during delivery, but protein S levels decreased from the second trimester and returned to normal non -pregnant values during delivery. High thrombin-antithrombin III level s showed that the coagulation system was activated during pregnancy fr om the first trimester. Maximum levels were reached during delivery. T hree days after delivery, the coagulation inhibitors returned to norma l non-pregnant values.