Purpose of the study: to determine the activity of intravascular blood coagulation during the abdominoplasty and justify pharmacological thromboprophylaxis.Material and Methods. An open prospective study was conducted on a group of 100 patients undergoing abdominoplasty. The risk of venous thromboembolism (VTE) before the surgery was assessed using the Caprini risk assessment model in 2010. Prothrombin (PT) and fibrinogen (FG) levels, soluble fibrin-monomer complexes (SFMC), euglobulin clot lysis time (ECLT), antithrombin III (AT-III) level, and protein C (PC) level were determined before and after the surgery.Results. Using the Caprini risk assessment model, patients were categorized by VTE risk as follows: moderate risk - 64% and high risk - 36%. After the surgery, an increase in PT by 12.3% and 15.5% on days 3 and 5 was observed (p < 0.01); an increase in FG by 0.49; 2.34 and 2.04 g/L on days 1, 3, and 5 was observed (p < 0.01); an increase in SFMC at all postoperative stages by 4.7; 8.2; 10.8 and 10.0 times (p < 0.01); an increase in ECLT by 2.8; 9.7, and 6.3 minutes on days 1, 3, and 5 (p < 0.001); and a decrease in AT-III and PC levels immediately after the operation by 18.8% and 8.9%, on day 1 by 14.2% and 11.2%, and on day 3 by 8.8% and 6.3% (p < 0.01).Conclusion. All patients undergoing abdominoplasty require pharmacological thromboprophylaxis due to moderate and high risk of venous thromboembolic complications. Abdominoplasty in the early postoperative period is accompanied by activation of plasma coagulation, inhibition of fibrinolytic system activity, and reduced activity of natural anticoagulants, which justifies the need for pharmacological thromboprophylaxis for at least 5 days.