Features of disorders and methods of correction of the hemostasis system in women with antenatal fetal death

Abstract

The improvement of the providing medical services quality to pregnant women remains an urgent issue in modern obstetrics. Women with perinatal losses deserve special attention, especially in the second half of pregnancy. Changes in the hemostasis system are an integral part of the development of pregnancy. The tendency to hypercoagulation has significant pathogenetic significance and can be the cause of a number of complications – miscarriage in the I trimester of pregnancy and preeclampsia, premature birth, antenatal fetal death (AFD) – in the II and III trimesters of pregnancy. Also, pregnancy is a background process for the activation of a number of diseases, in particular hereditary thrombophilia.The objective: to evaluate the changes in the hemostasis system in women with antenatal fetal death and the effectiveness of the use of low molecular weight heparins for the correction of disorders in the hemostasis system in this category of patients during childbirth and in the postpartum period.Materials and methods. 72 women were examined, including 42 pregnant women with AFD (main group) and 30 pregnant women with a physiological course of pregnancy, childbirth and the postpartum period (control group). The state of the hemostasis system was studied using a standard coagulogram. D-dimer was determined by immunoturbometric analysis.To assess the state of the hemostasis system, the following biochemical tests were used: procoagulant link – fibrinogen content and indicators: prothrombin index, activated partial thrombin time (APTT), thrombin time (TP), ancistrone time (AT), soluble fibrinogen-monomer complex (SFMC), factor X (FX); to evaluate the antithrombin system, the content of antithrombin-III (AT-III), protein C were determined; to characterize the state of the fibrinolytic system – the amount of plasminogen, α2-antiplasmin, fibrinogen degradation products (FDC).Thrombophilia markers and antiphospholipid antibodies were also determined. The preference was given to vaginal childbirth. During childbirth, mechanical compression of the lower limbs was applied using special compression stockings (compression level 2). In 12 hours after delivery thromboprophylaxis with low molecular weight heparins was started, the drug of choice being enoxaparin sodium. After 48 hours of the postpartum period, a comparative analysis of coagulogram indicators was performed to further determine the timing of thromboprophylaxis.Results. Analysis of family thrombotic anamnesis revealed risk factors in 12 (28.6%) patients of the main group. In close relatives of the first line, the presence of peripheral vein thrombosis was found – 5 (41.7%) cases, myocardial infarction under the age of 45 – 3 (25.0%) cases, pulmonary embolism – 1 (8.3%) case, transient ischemic attack of the brain – 3 (25.0%).In the control group only 2 (6.6%) patients had a family history of venous thromboembolism in first-line relatives. The analysis of the coagulation system shows significantly higher fibrinogen values (the main group – 5.3±0.2 g/l, the control group – 4.3±0.1 g/l; p<0.05), functional FX activity (the main group – 149.3±3.1%, control group – 107.3±2.7%; p<0.05), SFMC (main group – 15.9±1.2 μg/ml, control group – 7.8±0.9 μg/ml; p<0.05) and D-dimer (main group – 4.4±0.25 μg/ml, control group – 0.7±0.2 μg/ml; p< 0.05) in pregnant women of the main group. An increase in these indicators is a predictor of thrombus formation, activation of blood coagulation by the internal pathway with a decrease in the antithrombin reserve due to FX.During the correlation analysis, a strong direct relationship (r=0.8633) was established between the indicators of SFMC and FX in the blood serum of pregnant women of the main group, the combination of which determines the tendency to clot formation. Determination of markers for the most common types of thrombophilia shows the dominance of hereditary forms (prothrombin, Leiden mutation, MTHFR) in 43% of pregnant women of the main group.The implementation of the proposed treatment approach contributed to a significant decrease in the average concentration of fibrinogen 48 hours after delivery in postpartum women of the main group (main group: before delivery – 5.3±0.2 g/l, after 48 hours after delivery – 3.9±0.3 g/l; control group: 48 hours after delivery – 3.2±0.2 g/l; p<0.05) in combination with a synergistic decrease in the average indicators of SFMC (main group: before delivery – 15.9±1.2 μg/ml, 48 hours after delivery – 6.2±0.2 μg/ml; control group: 48 hours after delivery – 5.4±0.3 μg/ml; p<0.05) and FX (main group: before delivery – 149.3±3.1%, after 48 hours after delivery – 103.1±3.6%; control group: after 48 hours after delivery – 117.1±4.1%; p<0.05).Conclusions. Increased coagulation function was confirmed in pregnant women with antenatal fetal death (AFD). Thanks to the proposed method of correcting disorders in the hemostasis system, a decrease in the frequency of postpartum thromboembolism in women with AFD is achieved, as well as an improvement in the main indicators of the hemostasis system. This prevents the emergence of a chronic form of the syndrome of disseminated intravascular blood coagulation which is developed in the cases of AFD.