Fetal hemoglobin, blood transfusion, and retinopathy of prematurity in preterm infants: An observational, prospective study

PURPOSE: The objective of this study was to identify the association between fetal hemoglobin (HbF) concentration, blood transfusion, and retinopathy of prematurity (ROP) in preterm infants. METHODS: This was an observational, prospective study. A total of 410 preterm infants born with <36 weeks gestational age and <2.0 kg birth weight in a tertiary care center of central India for a period of 1 year were included in this study. Clinical data were obtained from case notes. HbF of infants was measured in the blood sample using high-performance liquid chromatography at the first visit and after 1 month follow-up and was analyzed statistically. Dilated fundus examination was done as per ROP screening guidelines, and ROP was classified as per the International Classification of Retinopathy of Prematurity (ICROP), 2021. The study subjects were divided into two groups based on the status of ROP. The relationship among HbF, blood transfusion, and ROP was evaluated in both the groups. The relationship between other clinical characteristics and various neonatal risk factors was also studied between the groups. RESULTS: A total of 410 preterm infants were included in this study, of which 110 infants had ROP (26.8%). Blood transfusion was found to be significantly associated with the development of ROP. Higher fraction of HbF (%) was associated with a lower prevalence of ROP. HbF was also inversely related with the severity of ROP. CONCLUSION: Replacing HbF by adult hemoglobin during blood transfusion may promote the development of ROP. Conversely, maintaining a higher percentage of HbF may be a protective factor against ROP.