What is the normal hemoglobin (Hb) level in children?

Normal Hemoglobin Levels in Children

Normal hemoglobin levels in children vary significantly by age, with the most clinically relevant threshold being 11.0 g/dL for children aged 6-24 months, below which anemia evaluation should be initiated. 1, 2

Age-Specific Normal Values

Infants and Toddlers (6-24 months)

• Average hemoglobin concentration: 12.0-12.5 g/dL 1, 2
• Lower threshold for anemia screening: 11.0 g/dL 1, 2
• Any child with hemoglobin below 11.0 g/dL requires evaluation for iron deficiency 1, 2

Newborns and Early Infancy

• At birth: approximately 15 g/dL is optimal 3
• Hemoglobin levels naturally decrease during the first 6 months of life, then gradually increase during childhood 1
• The percentage of fetal hemoglobin (Hb F) starts at 78.39±7.59% in cord blood and decreases rapidly in the first 6 months 4
• Adult hemoglobin (Hb A) increases from 21.14±7.04% at birth to 83.38±1.31% by the sixth month 4

School-Age Children

• A hemoglobin level of 11.6 g/dL in a 6-year-old child is within acceptable range 5
• Normal values continue to vary by age and sex throughout the pediatric period 5

Critical Factors Affecting Interpretation

Altitude Adjustments

• Add 0.2 g/dL for every 1,000 meters above sea level 6, 1, 2
• Children living at higher altitudes require upward adjustment of normal thresholds 6

Nutritional Status

• Iron intake significantly impacts hemoglobin levels, particularly in the 6-24 month age group 1
• Children consuming more than 24 oz of cow's milk daily are at increased risk for iron deficiency 1
• Breastfed infants without adequate iron from supplementary foods after 6 months are at risk 1

Clinical Pitfalls to Avoid

Do Not Rely on Hemoglobin Alone

• Less than 50% of children aged 1-5 years with anemia (Hb <11.0 g/dL) are actually iron deficient 1, 2
• Hemoglobin concentration cannot determine the cause of anemia 1
• Additional testing required: serum ferritin, transferrin saturation, MCV, red blood cell distribution width 1

Distinguish Iron Deficiency from Other Causes

• RDW >14% with low MCV suggests iron-deficiency anemia 1, 2
• RDW ≤14% with low MCV suggests thalassemia 1, 2
• Other causes include infection, sickle cell disease, and other nutritional deficiencies 1

Age-Related Variability

• Mean hemoglobin level and variability around the mean vary highly with age in children 6
• Do not confuse physiological variations by age and sex with pathological anemia requiring treatment 5

Screening Recommendations

High-Risk Populations (Universal Screening at 9-12 Months)

• Low-income families and WIC-eligible children 1
• Migrant children and recently arrived refugees 1

Selective Screening Indications

• Preterm or low birthweight infants 1
• Non-iron-fortified formula feeding for >2 months 1
• Introduction of cow's milk before 12 months 1
• Special health-care needs 1