THROMBOELASTOGRAPHIC ASSESSMENT OF COAGULATION DYNAMICS IN NORMAL PREGNANCY AND GESTATIONAL HYPERTENSION: ESTABLISHMENT OF REFERENCE INTERVALS AND DIAGNOSTIC IMPLICATIONS IN A SOUTH INDIAN COHORT

Abstract

Background: Pregnancy is characterized by a physiological hypercoagulable state resulting from alterations in coagulation and fibrinolytic pathways. These changes are further accentuated in hypertensive disorders such as gestational hypertension (GH), predisposing patients to thrombotic complications. Conventional coagulation tests provide limited insight into dynamic clot formation, whereas thromboelastography (TEG) offers a comprehensive real time assessment of hemostasis. Objectives: To establish reference intervals for TEG parameters in normal third-trimester pregnancy among South Indian women and to evaluate the diagnostic efficacy of TEG in detecting coagulation alterations in patients with gestational hypertension. Methods: This prospective observational study included 100 pregnant women in the third trimester, divided into two groups: normal pregnancy (Group N, n=50) and gestational hypertension (Group G, n=50). Venous blood samples were analyzed using TEG (TEG 5000 analyzer) to measure parameters including reaction time (R), clot formation time (K), alpha angle (α), maximum amplitude (MA), G value, and estimated percent lysis (EPL). Conventional coagulation parameters (platelet count, PT, INR) were also assessed. Statistical analysis was performed using SPSS v 26.0. Results: Gestational hypertension was associated with a hypercoagulable profile characterized by significantly reduced R time (1.966 vs. 4.184 min) and K time (1.228 vs. 1.578 min), along with increased alpha angle (72.98° vs. 67.58°), MA (68.45 vs. 62.81 mm), and G value (11.92 vs. 8.69), compared to normal pregnancy. Conventional parameters (PT and INR) showed only minimal differences between groups. Moderate correlations were observed between TEG parameters and PT/INR in the hypertensive group, indicating enhanced sensitivity of TEG in detecting coagulation dynamics. Conclusion: Thromboelastography demonstrated superior capability in identifying hypercoagulable states in gestational hypertension compared to conventional coagulation tests. Establishing pregnancy-specific reference intervals enhances its clinical applicability and may aid in early detection and targeted management.