[Prevention of venous thromboembolism with heparin in risk patients during pregnancy: monitoring by measuring thrombin-antithrombin III complex].

Women at high risk for thromboembolism deserve prophylactic treatment with heparin in the course of pregnancy. Since activation of the coagulation system is associated with an increase of TAT complexes which may well precede the clinical thrombosis, this parameter was used to determine start as well as dosage of the heparin prophylaxis. Thereby, the increase of TAT complexes during a normal pregnancy without thrombolic events had to be taken in account. 43 pregnancies of 40 patients who had already suffered from thrombotic events before pregnancy or had a positive family history were monitored by this method; in none of them any thromboembolic complication occurred. Duration of treatment and maximal amount of heparin showed wide individual variations and could not be predicted by clinical criteria. However, the total dose of heparin necessary was in many patients far below of what is usually administered, thus reducing the risk of heparin-induced osteoporosis and of local allergic reactions.