Hemoglobin Analysis in the First Year of Life

In newborns and infants during their first year of life, there is a dynamic change in the fraction of hemoglobin (Hb). To apply Hb analysis as a phenotypic diagnosis of thalassemia in newborns and infants, we need normal values of each Hb fraction for reference. Seventeen cord bloods from normal deliveries were collected for analysis. One hundred and thirty-seven infants from the pediatric outpatient clinic were recruited and were categorized by their ages into a series of short periods (month±2 weeks). Both alpha and beta thalassemia carriers detected were excluded. Samples with an Hb level less than 10.0 g/dL were also excluded. The proportion of Hb A (α2β2), A2 (α2δ2), and F (α2γ2) was obtained from high-performance liquid chromatography and analyzed according to its categorized periods. There were 90 (58.4%) specimens left for evaluation. The percentage of Hb A, A2, and F gradually changed with increasing age. The percentage of Hb A was 21.14±7.04% (mean±SD) in cord blood and increased substantially to 83.38±1.31% at the sixth month. The level was sustained thereafter. The incremental pattern of Hb A2 was similar to Hb A. The value was 0.32±0.19% at the beginning and reached a plateau with 2.78±0.25% at the sixth month. The percentage of Hb F started at 78.39±7.59% in cord blood and decreased rapidly in the first 6 months. The data possibly can be applied as quick guidance for interpretation of Hb analysis in newborns and infants during their first year of life.