Objective: The inexistence of
publications on hemoglobin values in the first six months of life gave us the
objective of describing these values, month by month in healthy, iron
sufficient exclusively breastfed infants. Methods: This was a cross-sectional descriptive study in
306 infants stratified according to age from one to six months, full-term
births, weighing ≥2500 g, without
intercurrences at birth, serum ferritin levels ≥10 ng/mL, followed by the public health service encouraging and supporting exclusive breastfeeding. An automated counter was used for
measuring hemoglobin, and serum ferritin was determined using immunoenzymatic method. Student’s t-test was used to analyze differences between means, and Mann-Whitney test when
distribution was non-normal. Level of statistical significance was p < 0.05. Results: The hemoglobin values, according to gender, did
not differ statistically in the different months; the results are presented without sample
division according to gender. Hemoglobin means and standard deviations in g/dL
were: 11.7(±1.6), 10.7(±1.5), 10.8(±1.3), 11.6(±1.5), 11.7(±1.7), and
11.8(±1.6), from the first to sixth month respectively. Conclusion: The
hemoglobin values obtained in all the first six months of life, based on a
healthy, exclusively breastfed infant population, may contribute to the
reassessment of reference levels for the diagnosis of anemia in the studied age
range.