Neonatal Anemia Etiology Pathophysiology Diagnosis Prevention
Keywords:
neonatal anemia, anemia of prematurity, preterm infants, hemoglobin, iron deficiency, erythropoietin, neonatal intensive careAbstract
Background: Neonatal anemia is a common hematological condition, particularly among preterm and very-low-birth-weight infants. It may result from blood loss, impaired erythropoiesis, hemolysis, iron deficiency, prematurity, and repeated iatrogenic blood sampling. Early recognition and appropriate management are essential because severe anemia may compromise tissue oxygen delivery and adversely affect neonatal outcomes. Objective: This review summarizes the current understanding of the etiology, pathophysiology, diagnosis, prevention, and management of neonatal anemia, with particular emphasis on anemia of prematurity and contemporary transfusion strategies. Methods: Recent scientific literature, clinical studies, systematic reviews, randomized controlled trials, and international clinical guidelines concerning neonatal anemia were reviewed, with emphasis on evidence published during 2020–2026. Results: Neonatal anemia is multifactorial and is strongly influenced by gestational age, birth weight, postnatal age, and clinical condition. Preterm infants are particularly vulnerable because of immature erythropoiesis, reduced erythropoietin production, limited iron stores, shortened red blood cell lifespan, rapid growth, and cumulative blood loss from laboratory testing. Diagnosis requires interpretation of hemoglobin and hematocrit according to gestational and postnatal age, combined with reticulocyte counts, blood smear examination, bilirubin assessment, and targeted investigations. Prevention includes delayed umbilical cord clamping, minimization of phlebotomy losses, adequate nutritional and iron support, and treatment of underlying causes. Current evidence supports individualized and restrictive red blood cell transfusion strategies. Conclusion: Neonatal anemia requires an individualized, evidence-based approach integrating prevention, timely diagnosis, and clinically appropriate treatment to optimize neonatal outcomes.
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