HEMATOLOGICAL AND COAGULATION CHANGES IN PHYSIOLOGICAL PREGNANCY

Abstract

The article presents a generalization of contemporary scientific data on hematological and coagulation changes during physiological pregnancy. It is shown that pregnancy is accompanied by significant adaptive alterations in the blood system, which ensure optimal conditions for fetal development, maintenance of placental circulation, and preparation of the maternal body for childbirth. The main components of these changes are highlighted, including hemodilution, physiological anemia of pregnancy, increased activity of the coagulation system, changes in platelet functional status, and features of fibrinolytic activity. It is noted that an increase in plasma volume by 40–50% leads to a relative decrease in hemoglobin and hematocrit levels, which is considered physiological anemia. The formation of a hypercoagulable state is described, обусловлене by increased levels of fibrinogen and coagulation factors (VII, VIII, X) and decreased activity of natural anticoagulants. It is emphasized that these changes are adaptive in nature; however, they are associated with an increased risk of thrombosis. The characteristics of the platelet component of hemostasis are analyzed, particularly the combination of a moderate decrease in platelet count with increased functional activity. It is shown that an imbalance between the coagulation and fibrinolytic systems may contribute to the development of gestational complications. The important role of hormonal, endothelial, and immune mechanisms in the regulation of hemostasis during pregnancy and the necessity of considering them in clinical practice are emphasized.

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