Complete blood count-derived inflammatory indices as potential markers in threatened abortion: A retrospective cohort study

This study aimed to evaluate complete blood count-derived inflammatory markers in women with threatened abortion and to investigate their association with threatened abortion. This retrospective cohort study included 802 pregnant women presenting before 20 weeks of gestation. Hematological parameters were compared between women with threatened abortion and healthy pregnant controls. Neutrophil, lymphocyte, platelet, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) values were evaluated. Multivariable binary logistic regression analyses were performed to identify factors independently associated with threatened abortion, with primary hematological parameters and derived inflammatory indices assessed in separate models to reduce multicollinearity. Women with threatened abortion had significantly lower lymphocyte counts and higher NLR and PLR values than controls (all P < .001), whereas neutrophil and platelet counts did not differ significantly. In multivariable analysis, lower lymphocyte count and higher neutrophil count were independently associated with threatened abortion. In the model including inflammatory indices, both NLR (odds ratio = 2.017, 95% confidence interval = 1.450–2.805; P < .001) and PLR (odds ratio = 1.033, 95% confidence interval = 1.022–1.044; P < .001) were independently associated with threatened abortion. Threatened abortion was characterized by lower lymphocyte counts and higher NLR and PLR values. These readily available inflammatory indices may serve as useful adjunctive markers for clinical assessment; however, prospective multicenter studies are needed to confirm their predictive utility.