Assessment of Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio among Pregnant Women with and without Pre-Eclampsia

Abstract

Background: Pre-eclampsia is associated with maternal inflammatory and haematological changes. The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are accessible indices derived from a routine complete blood count. Objective: To compare NLR, PLR, and selected blood-cell parameters in pregnant women with and without pre-eclampsia at a tertiary hospital in Nigeria. Methods: In this hospital-based comparative cross-sectional study, 366 pregnant women (183 with pre-eclampsia and 183 normotensive controls) were recruited consecutively. NLR and PLR were calculated from full blood counts. Analyses included group comparisons, correlations and exploratory logistic regression. Results: NLR was higher in the pre-eclampsia group (4.27 ± 1.32 vs. 2.79 ± 0.90; p < .001; mean difference, 1.48; approximate 95% CI [1.25, 1.71]), whereas PLR did not differ significantly (115.37 ± 40.78 vs. 121.47 ± 33.97; p = .121). Neutrophil and total white blood cell counts were higher, whereas lymphocyte and platelet counts were lower, in women with pre-eclampsia. Across the pooled sample, NLR correlated with systolic (rₛ = .456) and diastolic (rₛ = .463) blood pressure. Adjusted models were exploratory because of mathematically linked predictors and an undefined ANC-labelled covariate. Conclusion: NLR was higher among pregnant women with established pre-eclampsia in this tertiary-care sample, whereas unadjusted PLR values did not differ significantly. These cross-sectional associations do not establish independent diagnostic accuracy, future disease prediction or causal effects.