Platelet Count as an Early Screening Tool for Predicting Coagulation Abnormalities in Hypertensive Disorders of Pregnancy: A Retrospective Study

Abstract

Background: Hypertensive disorders of pregnancy (HDP), including gestational hypertension, preeclampsia, and eclampsia, are major causes of maternal and perinatal morbidity and mortality worldwide. Hematological abnormalities, particularly thrombocytopenia and coagulation derangements, are common in HDP and often precede clinical deterioration. Platelet count, a simple and routinely available investigation, may serve as an early and cost-effective marker for predicting coagulation abnormalities and disease severity. Aim: To assess the role of platelet count as an early screening tool for predicting coagulation abnormalities in hypertensive disorders of pregnancy. Materials and Methods: This retrospective cross-sectional study was conducted in the Department of Pathology at Sri Venkateshwaraa Medical College Hospital and Research Centre, Puducherry, over a one-year period from June 2024 to June 2025. Fifty pregnant women diagnosed with hypertensive disorders of pregnancy were included. Clinical and laboratory data were obtained from hospital records, including blood pressure measurements, platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), and international normalized ratio (INR). Data were analysed using SPSS version 26, with statistical significance set at p < 0.05. Results: Among the 50 participants, 32% had gestational hypertension, 44% had preeclampsia, and 24% had eclampsia. Mean platelet counts showed a progressive decline with increasing disease severity, from gestational hypertension (2.36 ± 0.51 × 10⁵/mm³) to preeclampsia (1.72 ± 0.46 × 10⁵/mm³) and eclampsia (1.22 ± 0.48 × 10⁵/mm³). Thrombocytopenia was observed in 42% of cases and was significantly associated with prolonged PT and aPTT and elevated INR values (p < 0.05). Platelet count demonstrated a significant negative correlation with PT (r = –0.58, p < 0.01) and aPTT (r = –0.64, p < 0.01). Maternal complications, including postpartum hemorrhage (28.6%), intrauterine fetal death (19%), and HELLP syndrome (14.3%), were more frequent among women with thrombocytopenia. Receiver operating characteristic (ROC) curve analysis demonstrated moderate predictive ability of platelet count for coagulation abnormalities, with an AUC of 0.70. At a cutoff value of 1.50 × 10⁵/mm³, sensitivity and specificity were 78% and 81%, respectively. Conclusion: Platelet count showed a significant inverse association with coagulation abnormalities and disease severity in hypertensive disorders of pregnancy. Routine platelet estimation can serve as a simple, early, and cost-effective screening tool for predicting coagulopathy, facilitating timely intervention and improving maternal and fetal outcomes.

Keywords: Hypertensive disorders of pregnancy; Preeclampsia; Eclampsia; Platelet count; Thrombocytopenia; Coagulation abnormalities; Prothrombin time; aPTT; INR; Maternal outcomes