GENERATION OF THROMBIN IN BLOOD-PLASMA OF NONPREGNANT AND PREGNANT-WOMEN STUDIED THROUGH CONCENTRATION OF THROMBIN-ANTITHROMBIN-III COMPLEXES

Objective: The main question in this study is how much more thrombin i s generated in blood plasma of pregnant women than in non-pregnant wom en. Study design: Thrombin-antithrombin III complexes (TAT) were used as markers of thrombin generation in vivo. They were measured by the E LISA method in blood plasma of 15 non-pregnant and 43 pregnant, as wel l as 30 parturient women and 10 women after delivery. Results: With no rmal menstrual cycles, TAT levels did not change significantly through out the cyclic phases, and the mean+/-S.D. calculated for all cyclic p hases was 1.9+/-0.3 mu g/l. In the 2nd trimester the level of TAT was 16.0+/-2.8 mu g/l and at term 21.5+/-11.9 mu g/l. Throughout the 1st a nd 2nd stage of labour the level of TAT increased insignificantly, but after placenta separation it was significantly higher than before lab our (30.8+/-20.4 mu g/l). In the 3rd and 7th days after delivery the l evel of TAT was still higher than in non-pregnant women. Conclusion: I t was found that the level of TAT in normal menstrual cycles is stable , whereas it increases in pregnancy. Relating the values of the cycle to those of pregnancy it was calculated, that at the end of pregnancy there is a ten-fold increase of TAT level and after placenta separatio n and expulsion - temporarily even fifteen-fold - increase. In the 3rd to 7th day after delivery, the TAT level was still higher than in non -pregnant women. (C) 1997 Elsevier Science Ireland Ltd.