Gynecology World Conference 2026

Background: Preeclampsia is a multisystem pregnancy complication affecting 5 to 10 percent of pregnancies worldwide and remains a leading cause of maternal and perinatal morbidity and mortality. Early identification of reliable, cost-effective biomarkers is critical for timely diagnosis and intervention. The neutrophil to lymphocyte ratio NLR, derived from routine complete blood count, has emerged as a candidate inflammatory marker. However, findings across studies remain inconsistent. This systematic review aimed to evaluate the evidence regarding NLR as a predictive or diagnostic marker for preeclampsia.

Methods: This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and MetaAnalyses PRISMA 2020 guidelines. A comprehensive literature search was performed across electronic databases including PubMed and ScienceDirect using keywords: neutrophil to lymphocyte ratio NLR, preeclampsia and pregnancy. Inclusion criteria were: 1. observational studies cohort, case control, or cross sectional design, 2. conducted in human subjects pregnant women, 3.reporting NLR values, 4. reporting preeclampsia as an outcome, and 5. full text available in English. Studies were excluded if they were reviews, meta analyses, editorials, case reports, animal studies, or had incomplete data regarding NLR or preeclampsia outcomes. After screening titles, abstracts, and full texts using the PRISMA flow diagram, five studies met the eligibility criteria and were included in the final synthesis.

Results and Discussion: Across the included studies, NLR was measured from peripheral blood samples using automated hematology analyzers. Findings regarding NLR in preeclampsia were heterogeneous. Taskomur and Erten 2021 reported that NLR was significantly elevated in severe preeclampsia compared to healthy pregnancies 4.51 vs. 3.63, p = 0.04, though it lacked diagnostic accuracy on ROC analysis AUC = 0.582.

Kassahun et al. (2024) demonstrated a statistically significant difference in NLR between preeclamptic and normotensive women (4.33 vs. 3.50, p = 0.016), with an AUC of 0.609 and a cut-off of 3.80. In contrast, Moller et al. (2023) found NLR to be significantly higher in healthy controls compared to preeclamptic women among multigravida (p = 0.014), with a modest AUC of 0.597. Kapci et al. (2024) reported no significant difference in NLR between preeclampsia and control groups (p = 0.131), with the systemic immune-inflammation index (SII) demonstrating superior diagnostic performance (AUC = 0.705). Seyhanli et al. (2024) similarly found no predictive value of NLR for preeclampsia in the first trimester (AUC = 0.536, p = 0.315), with SIRI and PIV emerging as more significant predictors.