Objective: To compare the peripheral white blood cell [WBC] and its differential counts in early pregnancy of women who
developed and who did not develop preeclampsia [PE]. Predictive ability of total WBC and differential counts for the risk of PE was also determined.
Materials and Methods: Data from singleton pregnant women who firstly attended the antenatal clinic at gestational age [GA] of <16 weeks were collected. WBC and differential counts were categorized into quartiles, and the odds ratio of
developing PE comparing each of the upper quartiles with the lowest quartile were analyzed.
Results: The study population consisted of 4,868 gravidas. Of these, 328 (6.7%) developed PE. Total WBCs, absolute
neutrophil count, and a ratio of neutrophils to lymphocytes (N/L ratio) were significantly elevated while absolute lymphocyte count was significantly decreased in PE compared to non-preeclamptic gravidas. These four variables were also identified as significant risk factors for PE by multivariable analysis. The most powerful predictor was the WBC count, with the fourth quartile (>8,800/μL) versus the first quartile (<7,200/μL) increasing the risk by 6.2 folds.
Conclusion: Peripheral total WBC and differential counts in early pregnancy were identified as significant risk factors for
PE.

Keywords: Differential count, Preeclampsia, White blood cell