Creator: ReportSense
Published: 2026-08-04T00:00:00.000Z

Your child's blood test report came back with values that look alarming compared to an adult reference range - but are actually normal for their age. Or the opposite: a value appears "normal" on the printed range but is low for a young child.

Paediatric blood test interpretation requires age-specific reference ranges. This guide covers the most commonly ordered tests for children in India and what normal looks like at different ages.

Complete Blood Count (CBC)

Haemoglobin

Age	Normal Haemoglobin (g/dL)
Newborn (0-2 weeks)	13.5 - 20.0
2 months	9.0 - 14.0
6 months - 2 years	10.5 - 13.5
2 to 6 years	11.5 - 13.5
6 to 12 years	11.5 - 15.5
Adolescent boys (12-18)	13.0 - 17.0
Adolescent girls (12-18)	12.0 - 16.0

Newborns have very high haemoglobin (foetal haemoglobin) that falls sharply in the first 2-3 months - this is normal "physiological anaemia of infancy." Adult reference ranges should never be applied to neonates or infants.

Anaemia in children is extremely common in India. Studies suggest 50-60% of Indian children under 5 have anaemia, predominantly from iron deficiency.

White Blood Count (WBC/TLC)

Age	Normal WBC Range (per µL)
Newborn	9,000 - 30,000
2 weeks to 2 months	6,000 - 17,000
6 months to 2 years	6,000 - 17,000
2 to 6 years	5,000 - 15,000
6 to 12 years	4,500 - 13,000
Above 12 years	4,500 - 11,000

Young children normally have higher WBC than adults - their immune systems are actively learning. A WBC of 12,000 in a 3-year-old is not concerning; the same value in an adult warrants investigation.

Platelet Count

Normal platelet count in children (1.5-4.0 lakh) is similar to adults. Dengue-related platelet drops, which are concerning at any age, are interpreted the same way.

Thyroid Function

Age	TSH Normal Range
Newborns (3 days)	1.0 - 39.0 mIU/L (very wide in first days)
1 to 4 months	1.7 - 9.1
2 to 20 years	0.7 - 5.7

Neonatal TSH is much higher than adult normal - this is expected. The very high adult reference range should not be applied to newborns. Neonatal TSH screening (heel prick test at birth) is specifically designed to catch congenital hypothyroidism.

Kidney Function

Creatinine rises with age as muscle mass grows:

Age	Creatinine Normal (mg/dL)
0 to 2 years	0.2 - 0.4
2 to 6 years	0.3 - 0.5
6 to 12 years	0.4 - 0.7
12 to 18 years	0.5 - 1.0

A creatinine of 0.8 that is completely normal in an adult is elevated in a 5-year-old. eGFR is more meaningful than raw creatinine in children too - paediatric eGFR formulas (Schwartz formula) differ from adult formulas.

Liver Function

SGPT/ALT and SGOT/AST are higher in children than adults - particularly in infants:

Age	SGPT (ALT) Normal
0 to 1 year	Up to 54 IU/L
1 to 5 years	Up to 45 IU/L
5 to 12 years	Up to 35 IU/L
Above 12 years	Adult ranges apply

ALP (alkaline phosphatase) is significantly elevated in children due to bone growth - values of 200-400 IU/L are normal in growing children and should not be interpreted as liver disease.

Iron and Nutrition

Ferritin (Iron Stores)

Age	Ferritin Lower Limit
Infants 6 months - 2 years	10 ng/mL
Children 2 - 12 years	10-20 ng/mL
Adolescents	Similar to adults

Iron deficiency is the most common nutritional deficiency in Indian children. A ferritin below 10-12 ng/mL at any paediatric age indicates iron deficiency - regardless of haemoglobin.

Key Differences to Remember

Apply age-specific reference ranges - never assume adult normal applies to a child
Newborn and infant values differ dramatically from older children
ALP is high in growing children - this is not liver disease
WBC is higher in young children - this is not necessarily infection
Creatinine rises gradually with age - a "normal adult" creatinine can be elevated in a young child

Must Read

How to Read Your CBC Report - All CBC parameters explained
Blood Test Normal Ranges: Men vs Women - How adult reference ranges differ by sex

Try ReportSense on your own report. ReportSense applies age-appropriate reference ranges when you select a child's profile - so you get an interpretation that is calibrated to your child's age, not just copied from the adult reference table on the lab report. Try it free at reportsense.in.