Admission blood gas, platelet, and inflammatory parameters associated with intraventricular hemorrhage in preterm infants: a retrospective case-control study.

Objectives: This study aimed to evaluate the association between admission blood gas, platelet, and inflammatory parameters and the presence of IVH. Methods: This retrospective case-control study included 356 preterm infants admitted to a tertiary neonatal intensive care unit between 2016 and 2025, including 165 infants with IVH and 191 without IVH. Initial blood gas and complete blood count parameters were analyzed. Multivariable logistic regression was used to identify independent factors associated with IVH. Results: Lower gestational age was significantly associated with IVH presence and severity (p<0.001). Lactate levels were higher in the IVH group (3.10 vs. 2.60 mmol/L; p=0.013). In the exploratory integrated model including gestational age, lactate, platelet count, MPV, and the N/L ratio, lactate showed a borderline association with IVH (OR=1.099, 95 % CI: 0.995-1.214; p=0.063), whereas lower platelet count, lower MPV, and higher N/L ratio remained independently associated with IVH. Conclusions: Lower platelet counts, lower MPV values, and higher N/L ratios were independently associated with IVH in the exploratory integrated model, while admission lactate showed a borderline association after adjustment for gestational age and hematological parameters. These findings should be interpreted as early associations rather than validated predictive biomarkers, and prospective studies with standardized cranial ultrasonography and external validation are needed.