Abstract
BACKGROUND: Preeclampsia (PE) complicated by fetal growth restriction (FGR) is associated with high pediatric morbidity and mortality. The current predictive model mainly focus on using ultrasound or serum biomarkers that is relative high testing cost and a lack of technical accessibility in low-income countries. Our study aimed to investigate whether the occurrence of FGR in patients with PE could be predicted using results from low-cost complete blood count (CBC) tests at 20-24 weeks of gestation. METHODS: In this retrospective study, we reviewed all cases of patients with PE who received routine prenatal care and delivered at our hospital from April 2019 to April 2022. Patients diagnosed with PE were paired with healthy pregnant women using 1:1 matching on the basis of similar age, parity, and pregestational body mass index (BMI). Routine peripheral blood cell results between 20 and 24 weeks of gestation were collected and analyzed using logistic regression to identify independent risk factors in the normotensive pregnancy, the PE with FGR and the PE with normal birth weight (NBW) groups. A nomogram was subsequently developed to quantify the risk of FGR in patients with PE. Finally, we assessed the model's predictive performance. RESULTS: A total of 392 patients with PE were included, consisting of 66 patients with FGR, 326 with NBW, and 392 with normotensive pregnancies. The nomogram included three independent risk factors: a lymphocyte count ≥ 2.05 × 10(9)/L, a neutrophil-to-lymphocyte ratio (NLR) ≤ 4.04, and a platelet-to-lymphocyte ratio (PLR) ≤ 93.51. The diagnostic performance of the nomogram was moderate, with an area under the curve (AUC) of 0.72, a specificity of 80.1%, and a sensitivity of 54.5%. Furthermore, the nomogram was validated through a decision curve analysis (DCA), which demonstrated a favorable positive net benefit, and the calibration curve showed a good fit and alignment with the ideal curve. Finally, the patients based on the total score from nomogram model were stratified into low-risk (≤ 60 scores) and high-risk groups (> 60 scores). CONCLUSIONS: Our predictive model, based on routine peripheral blood cell results at 20-24 weeks of gestation, could provide insight into earlier prediction of FGR occurrence in patients with PE, facilitating further fetal monitoring and clinical decision-making.