© 2022, Faculdade de Ciencias Farmaceuticas (Biblioteca). All rights reserved.The effect of hypothermia treatment on white blood cell (WBC), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR) and platelet-to-lymphocyte ratio (PLR) values as an indicator of inflammation was evaluated in newborns with hypoxic ischemic encephalopathy (HIE). The study was performed that the before-therapeutic hypothermia (TH) and after-TH WBC, lymphocytes, neutrophils, monocytes and NLR, LMR and PLR values of the complete blood cell count were retrospectively evaluated. The results of the patient group were compared with the results of healthy newborns. A total of 78 patients who underwent TH were evaluated in our study. Mean values before and after TH were NLR3.8/2.7, LMR 5.6/8.6, and PLR 60.3/67.1 respectively. A statistical significance was present for NLR values before and after TH in those with seizure in our study (4.15±2.95/3.01±2.54) but no statistical significance was found for LMR or PLR. In neonates with HIE, effect of TH on complete blood cell count and inflammatory mechanisms (mediated neutrophil and lymphocyte) may be minimal.