THE ASSOCIATION BETWEEN FETAL HEMOGLOBIN AND PREECLAMPSIA

Abstract

Background: Preeclampsia is a leading cause of maternal morbidity and mortality worldwide, and early diagnosis is essential to reduce adverse maternal and neonatal outcomes. Fetal hemoglobin (HbF) has been proposed as a potential biomarker involved in the pathogenesis of preeclampsia through its effects on placental and maternal vascular function. Aim of study: To evaluate the association of maternal serum levels of fetal hemoglobin in the diagnosis of preeclampsia and its severity. Patients and methods: This case-control study was conducted in the Obstetrics and Gynecology Department at Baghdad Teaching Hospital from 1 January to 1 November 2024 and included 100 pregnant women between 20 and 36 weeks of gestation. Participants were divided into two groups: 50 women with preeclampsia (23 mild/moderate, 27 severe) and 50 normotensive controls. Maternal serum HbF levels were measured and compared between groups, and diagnostic performance was evaluated using different cut-off values. Results: Mean serum HbF levels were 1.25 ± 0.19 μg/ml in severe preeclampsia, 0.87 ± 0.23 μg/ml in mild/moderate preeclampsia, and 0.42 ± 0.17 μg/ml in controls (p < 0.001). An HbF cut-off of 0.75 μg/ml for diagnosing preeclampsia yielded a sensitivity of 84%, specificity of 80%, positive predictive value (PPV) of 80.7%, and negative predictive value (NPV) of 83.3%. For severe preeclampsia, a cut-off of 0.85 μg/ml showed a sensitivity of 74.1%, specificity of 69.9%, PPV of 85.7%, and NPV of 75.8%. Conclusion: Elevated maternal serum fetal hemoglobin is significantly associated with both the occurrence and severity of preeclampsia, and HbF appears to be a promising, simple, and accessible biochemical biomarker for the diagnosis and risk stratification of preeclampsia.