Can the Systemic Immune-Inflammation Index (SII) Predict the Outcome of Threatened Miscarriage?

Aim: Inflammatory markers have gained attention in recent years and the search continues for cost-effective, widely available, easily applicable, and interpretable biomarkers that can more accurately predict pregnancy outcomes. The study aims to determine a cut-off value for systemic immune-inflammation index (SII) (neutrophil × platelet /lymphocyte) in the prediction of the outcome of threatened miscarriage (TM). Materials and Methods: This retrospective case-control study was designed at the Obstetrics-Gynecology and Perinatology Clinics. Singleton pregnant women with TM who were followed up in the outpatient clinics or hospitalized and whose pregnancy resulted in our hospital were included in the study. Women whose pregnancies resulted in miscarriage were included in Group I. Women whose pregnancies resulted in childbirth were in Group II. Receiver operating characteristic (ROC) curves were used to assess the performance of inflammatory indexes in predicting the outcome of TM. Results: A total of 730 pregnant women with the diagnosis of TM were included in the present study. There were 239 patients in Group I and there were 491 patients in Group II. SII was statistically significantly higher in Group II (856.6 vs. 938.4; p