Preeclampsia patients show significant relationship between platelet indices and leucocyte parameters: Study

The exact etiology of PE remains unclear. However, abnormal placentation plays a key role. Maternal uterine spiral arteries undergo vascular remodelling throughout the first trimester of a normal pregnancy. Trophoblast cells penetrate spiral arterioles and transform muscular arteries into large-bore, low-resistance vessels with high capacity. In first-trimester (10-12 weeks) trophoblasts invade up to decidual segments. The second wave invasion happens during 16-18 weeks and invade up to myometrial segments. By 20 weeks of pregnancy, this procedure is usually completed. In PE, this placentation process is disturbed and spiral arteries remain in a high resistance, vasoconstricted state. This leads to impaired blood supply to foeto-placental unit and results in placental ischemia-reperfusion damage. Consequently, toxic substances such as free radicals are formed, causing placental oxidative stress (OS). The ischemic placenta produces inflammatory, anti-angiogenic, and oxidative chemicals, leading in systemic inflammation, oxidative stress, and activation of endothelium. The clinical presentation of PE occurs when endothelial activation and dysfunction develops in peripheral organs such as the liver, kidney, or brain. Further, which causes disturbance in the haemodynamic changes necessary for maternal adaptation to pregnancy.

PE is a proven risk factor for developing cardiovascular disease later in life. However, the question of whether inflammatory system activation occurs with PE and whether the present evidence is sufficient to justify extensive autoimmune system treatment techniques is currently being debated.

Platelets play a key role in inflammatory process, wound healing, remodelling, angiogenesis, and microbial host defence, in addition to their critical role in hemostasis and thrombosis. Platelet indices, which include ‘mean platelet volume (MPV) and platelet distribution width (PDW), as well as platelet large cell ratio (PLCR), are a series of platelet characteristics collected as part of complete blood count. Platelets indices have been recently used in the prediction, diagnosis, and prognosis of many diseases, including preeclampsia. Platelet indices are platelet activation biomarkers. Platelet distribution width (PDW), Mean platelet volume (MPV), and platelet large cell ratio (PLCR), calculated collectively in CBC profiles.

Even though the exact cause of elevated blood pressure in preeclampsia is obscure, platelets get activated and attach to endothelium at the site of injury. In the early stages of hypertension in pregnancy, platelet aggregation is increased. As a result, the bone marrow produces large, young platelets, resulting in an increase in mean platelet volume (MPV). Early prediction of development of Preeclampsia is an important preventive strategy to reduce maternal as well as foetal morbidity and mortality. Hence, the present study was carried out: (a) To assess the significance of Platelet indices, NLR and PLR as early pregnancy parameters to predict occurrence of Preeclampsia; (b) To analyse the significance of Platelet indices, NLR and PLR as early pregnancy parameters to predict occurrence of Foetal Growth Restriction (FGR).

A prospective study carried out on 135 pregnant women in 8-14 weeks of pregnancy either visiting to OBG OPD for regular checkups or admitted under OBG department of JSS Hospital, Mysuru, Karnataka. A complete blood count was performed. “Hemoglobin, platelet count, mean platelet volume (MPV), plateletcrit, platelet distribution width (PDW), lymphocyte count, and neutrophil count were measured. Neutrophil to lymphocyte ratio (NLR) and Platelet to lymphocyte ratio (PLR) were calculated.

In this study, 73 (54.1%) subjects were in age group of < 25 years. Majority of women (50.4%) were primigravidae. During follow-up, 35 (25.9%) women found to have preeclampsia. Mean platelet count, plateletcrit (PCT) and PDW were lower among women who developed preeclampsia and even more in severe PE compared to normal subjects. Mean Neutrophil and NLR were higher among women who developed preeclampsia and more so in severe PE. Mean lymphocyte count and PLR were lower in subjects who developed preeclampsia compared to normal subjects. Among 135, 20 had foetal distress of which 45% of babies were born to mothers with preeclampsia. A total of 23 (17.0%) women had foetal growth restriction. Mean platelet count, plateletcrit, PLR were lower among women who had foetal growth restriction compared to normal subjects.

In conclusion, platelet count, neutrophil and lymphocyte count, MPV, NLR and PLR were useful to detect the risk of PE, due to increased platelet destruction, inflammatory process and platelet turnover in patient with preeclampsia. Increasing MPV, PDW and PCT along with decreasing platelet count, Lymphocyte count and PLR may play a role in predicting preeclampsia. Furthermore, measurement of platelet indices and leucocyte counts may be regarded as a simple, reliable, cost-effective, and timelier method for detecting preeclampsia and determining its severity. Further studies with large sample size are recommended.

Source: Srinivasa et al. / Indian Journal of Obstetrics and Gynecology Research 2025;12(3):555–562