The course of pregnancy and blood coagulation system

Abstract

Pregnancy represents the procoagulant state, giving rise in the high prevalence rate of thrombotic complications. An imbalance between coagulation and anticoagulation systems of blood during pregnancy can lead to the development of pre-eclampsia, intrauterine growth retardation, preterm labor, premature rupture offetal membranes and fetal death. These complications are mostly caused by the impaired generation of thrombin as well as changes in the concentration and activity of tissue factor TFPI (tissue factor pathway inhibitor), TAT III complex and protein Z. Nevertheless, it should be noted that the thrombotic complications during pregnancy depend not on the elevation of the concentrations of specific coagulation factors or lack of the activity of anticoagulant proteins, but on the shift in the whole system toward the procoagulant state. These disorders most of all lead to thromboses ofplacental vessels, causing disorders ofperfusion of the affected area. Placental pathology can develop as from the maternal as from the fetal side. Despite the fact that changes in the blood coagulation system occur from the very beginning of pregnancy, and often are adaptive in nature, i.e., do not require special medical intervention, the prompt diagnosis and treatment of hemostatic disorders as main pathogenetic link in the development of thrombosis is extremely important.