Inflammatory Indices and Preterm Delivery: A New Horizon in Obstetric Risk Assessment.

Preterm delivery is a leading cause of neonatal morbidity and mortality globally, with inflammation playing a crucial role in its pathophysiology. This study aimed to evaluate the predictive value of systemic inflammatory response indices in identifying pregnant women at risk of preterm delivery. This retrospective study analyzed data from 1128 pregnant women admitted to a tertiary care hospital between 2020 and 2025. Patients were classified into two groups: preterm delivery ( = 528) and term delivery ( = 600). Demographic characteristics, obstetric history, neonatal outcomes, and inflammatory indices were compared. The preterm delivery group showed a significantly higher systemic inflammatory response index (SIRI) ( < 0.001), systemic immune-inflammation index (SII) ( < 0.001), neutrophil/lymphocyte ratio (NLR) ( < 0.001), and monocyte/lymphocyte ratio (MLR) ( < 0.001) than the term delivery group, while platelet/lymphocyte ratio (PLR) levels were significantly lower ( = 0.002). Inflammatory indices were higher in early preterm delivery cases ( < 0.001) than in middle and late preterm cases. Multivariate logistic regression identified the SIRI ( = 0.015) and NLR ( < 0.001) as independent predictors of preterm delivery, while the PLR showed an inverse association ( = 0.002). Higher inflammatory indices correlated with lower 1st and 5th minute APGAR scores ( < 0.001) and increased neonatal intensive care unit (NICU) admission rates ( < 0.001). NICU stay was prolonged in neonates born to mothers with elevated SIRI and NLR levels ( < 0.001). Integrating these inflammatory indices into obstetric risk assessment may enhance early detection and intervention strategies, potentially improving maternal and neonatal prognosis.