A child’s growth is one of the clearest windows into their health. Faltering growth can signal malnutrition, chronic illness, HIV, tuberculosis, feeding problems, neglect or other conditions, often before obvious symptoms appear. Rapid weight gain can also signal emerging obesity. Nurses in child welfare clinics, immunisation sessions, outpatient departments and community programmes are often the professionals best placed to spot these problems.
Why growth monitoring matters
According to UNICEF, WHO and the World Bank, millions of children under 5 worldwide are affected by stunting (being too short for age) and wasting (being too thin for height), while a growing number are overweight. Undernutrition contributes to a large share of child deaths. Early detection allows early support, from feeding advice to therapeutic food and treatment of underlying illness.
Key measurements
Weight
- Use calibrated scales, zeroed before each measurement.
- Weigh infants naked or in a dry nappy; older children in light clothing without shoes.
- Record to the nearest 10 to 100 g depending on the scale.
Length and height
- Under 2 years: measure length lying down on a length board, with one person holding the head against the headboard and another straightening the legs and moving the footboard against the heels.
- 2 years and over: measure standing height with a stadiometer, heels, buttocks, shoulders and head touching the board, looking straight ahead.
- Record to the nearest 0.1 cm.
Head circumference
Measured in infants with a non-stretch tape around the widest part of the head. Abnormal growth may indicate neurological or developmental problems.
Mid-upper arm circumference (MUAC)
MUAC is a simple, quick and reliable way to screen children aged 6 to 59 months for acute malnutrition, particularly in community and emergency settings.
- Use the child’s left arm, with the arm relaxed and hanging by the side.
- Find the midpoint between the tip of the shoulder (acromion) and the tip of the elbow (olecranon) with the elbow bent at 90 degrees, and mark it.
- Straighten the arm and wrap the MUAC tape around the midpoint, snug but not tight (no gaps, no pinching the skin).
- Read the measurement in the window to the nearest millimetre.
WHO and UNICEF cut-offs for children 6 to 59 months:
- Red: less than 115 mm = severe acute malnutrition (SAM)
- Yellow: 115 to less than 125 mm = moderate acute malnutrition (MAM)
- Green: 125 mm or more = not acutely malnourished
Check for oedema
Press firmly with your thumbs on the tops of both feet for about 3 seconds. If a pit remains in both feet, the child has bilateral pitting oedema, a sign of severe acute malnutrition (kwashiorkor), regardless of weight or MUAC.
Using WHO growth charts
WHO Child Growth Standards (for 0 to 5 years) describe how children should grow in optimal conditions, regardless of ethnicity. Many countries include them in child health booklets or “road to health” cards. Key indicators:
- Weight-for-age: underweight
- Length/height-for-age: stunting (chronic undernutrition)
- Weight-for-length/height: wasting (acute undernutrition) or overweight
- BMI-for-age: overweight and obesity
Results are expressed as z-scores (standard deviations from the median):
- Below −2 z-scores: moderately underweight, stunted or wasted
- Below −3 z-scores: severely underweight, stunted or wasted
- Above +2 z-scores (weight-for-height or BMI): overweight; above +3: obese
Plot every measurement and look at the trend. A single measurement is a snapshot; a line on a chart tells a story. A child whose curve is flattening or crossing centile lines downward needs attention even if they’re still within the “normal” range.
What to do with the findings
Severe acute malnutrition (MUAC under 115 mm, weight-for-height below −3 z, or bilateral oedema)
- Check for medical complications and appetite. Children with complications (such as poor appetite, severe oedema, infection, dehydration, hypothermia or hypoglycaemia) need inpatient care.
- Children with good appetite and no complications can often be treated in outpatient programmes (such as CMAM) with ready-to-use therapeutic food (RUTF), antibiotics and regular follow-up.
Moderate acute malnutrition
- Refer to supplementary feeding programmes where available.
- Counsel on feeding, check for illnesses, and follow up regularly.
Growth faltering
- Take a feeding history: breastfeeding, complementary foods, frequency, food variety.
- Look for illness: diarrhoea, infections, TB, HIV, worms.
- Consider social factors: food insecurity, maternal health, neglect.
- Give targeted counselling and arrange follow-up.
Overweight
Discuss healthy eating, sugary drinks, screen time and physical activity with the family, without blame.
Counselling families
- Explain the growth chart to parents. Many find it motivating to see their child’s line.
- Praise good practices.
- Give one or two practical, achievable feeding messages rather than a long list.
- Encourage exclusive breastfeeding for 6 months, then nutritious complementary foods with continued breastfeeding up to 2 years or beyond.
- Book follow-up visits.
Common errors to avoid
- Using uncalibrated scales or not zeroing them
- Measuring length incorrectly (knees bent, head not against the board)
- MUAC tape too loose or too tight, or measured at the wrong point
- Not checking for oedema
- Recording but not plotting, or plotting without interpreting
- Using the wrong chart (age, sex or measurement type)