Systemic Inflammatory Indices in Preterm Preeclampsia Versus Term Preeclampsia and Healthy Pregnancies: A Retrospective Case-Control Study

Abstract

Aim: This study aimed to investigate whether systemic inflammatory indices derived from first-trimester complete blood counts—namely the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and pan-immune-inflammation value (PIV)—differ among women with preterm preeclampsia, term preeclampsia, and healthy pregnancies. Material and Method: In this retrospective case–control study, 197 pregnant women were evaluated and categorized into three groups: preterm preeclampsia (n=39), term preeclampsia (n=59), and healthy controls (n=99). Demographic, perinatal, and hematological data were retrieved from medical records. Inflammatory indices were calculated from complete blood count parameters obtained during the first trimester. Statistical comparisons across groups were performed using one-way ANOVA or Kruskal–Wallis test, with a significance threshold of p<0.05. Results: While neutrophil counts and hemoglobin levels were significantly higher in preeclampsia groups compared to controls (p=0.001 and p<0.001, respectively), there were no statistically significant differences among groups in terms of NLR (p=0.063), PLR (p=0.750), SII (p=0.100), SIRI (p=0.110), or PIV (p=0.091). Birth weight, birth length, and Apgar scores were significantly lower in the preterm preeclampsia group (p<0.001 for all), reflecting more severe neonatal outcomes. Conclusion: Despite differences in neutrophil count and hemoglobin concentration, systemic inflammatory indices derived from first-trimester blood counts did not significantly differentiate preterm preeclampsia from term preeclampsia or healthy pregnancies. These findings suggest limited utility of these indices as standalone diagnostic markers in early pregnancy. Future prospective studies incorporating serial measurements and multimodal predictive models are warranted.

Keywords

• First-trimester screening
• maternal biomarkers
• preeclampsia
• preterm preeclampsia
• systemic inflammation

Kaynakça

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