Conditions

Growth assessment/Short stature

Short stature is when your height is significantly lower than what would be expected for your age and sex. Shortness is most often due to genes that are inherited from your parents. However, sometimes short stature and slow growth can be a sign of an underlying problem such as a hormonal issue, health condition or poor nutrition.

Key points

  1. The height you reach as an adult partly depends on the genes you inherited from your parents, so if your parents are short, you are more likely to be short. Children also grow at different rates and most children who are very short are completely healthy.
  2. A health condition that affects growth is more likely if your child is growing slower than expected, or their rate of growth slows down.
  3. Illnesses or poor nutrition during childhood or being small or premature at birth may also mean children do not reach their full potential adult height.
  4. See your doctor if your child seems to be particularly short compared to other girls or boys of the same age, or if their rate of growth has slowed down.
  5. Sometimes treating an underlying condition or hormonal issue will mean your child can grow to a normal height.

What is the definition of short stature?

Short stature is defined as height that is two standard deviations below the average height for age and sex or more than two standard deviations below the mid-parental height. Your doctor will know how to work out whether your child’s height is outside the normal range for girls or boys their age. 

What are the causes of short stature?

Causes of short stature include:

  • genes for short height inherited from parents
  • delayed growth that is within the normal range
  • a genetic disorder affecting height, such as Down syndrome, Prader-Willi syndrome and Turner syndrome
  • an underlying hormone-related condition, such as not enough thyroid or human growth hormone
  • being born small or premature
  • an underlying condition, such as coeliac disease or inflammatory bowel disease, that affects the ability to absorb nutrients
  • an underlying disorder of the skeleton (skeletal dysplasia)
  • malnutrition from neglect.

Sometimes, the cause is not known.

When should I take my child to a doctor?

See your doctor if your child:

  • seems to be particularly short compared to other girls or boys of the same age
  • is not growing at their normal rate
  • has delayed puberty – in girls puberty is normally before 13 years, in boys before 14 years
  • is being bullied or if their height or growth rate seems to be affecting their sense of wellbeing.

How is short stature diagnosed?

Because there are lots of reasons for short stature, your doctor will do a thorough assessment. They will ask about your child’s birth weight and whether they were premature, as well as the family history of height and timing of puberty. They will examine your child, including measuring their height and working out whether it is outside the usual range for a girl or boy their age.

They will also do blood tests to check their hormone levels and whether there is any underlying illness. They may also arrange an x-ray to check your child’s ‘bone age’. They may ask questions about your child’s eating habits and whether they have issues such as loose bowel movements (runny poos), sore tummy, low mood, poor concentration, etc. These symptoms may indicate an underlying condition, such as coeliac disease or inflammatory bowel disease

How is short stature treated?

If your child is short but healthy, they will not need treatment unless it is affecting their mental health, such as because of bullying or delayed puberty. If this is the case, talk to your doctor about getting them some psychological support or find a counsellor or therapist yourself.

If your child has an underlying condition causing short stature, such as coeliac disease or inflammatory bowel disease, the aim of treatment will be to improve the absorption of nutrients. For coeliac disease, this will involve following a strict gluten-free diet. For IBD, anti-inflammatory medicines and dietary modifications may be part of the treatment strategy. Improving absorption of nutrients will help your child to catch up and grow nearer to their potential adult height.

If tests show that your child does not have enough growth hormone, they can be treated with artificial growth hormone, which will help them to catch up and reach a normal height. Growth hormone can help to increase the final adult height of children with Turner syndrome, Prader-Willi syndromekidney-disease and some children who were of very low birth weight for their gestational age.

Once the skeleton has stopped growing, there are no drug treatments to increase height. However, some adults have growth hormone treatment to help maintain muscle bulk, a healthy skeleton and normal energy levels. Surgery to stretch legs has risks of complications, which means it is not usually carried out.

How can I prevent short stature?

If short stature has been inherited from your parents, it cannot be prevented. Otherwise, it’s important to follow good nutrition advice for babies and children to support their healthy growth and development. If your child’s rate of growth slows down or if they are noticeably shorter than other girls or boys their age, take them to your doctor. 

If there is an underlying genetic condition, such as Down syndrome, Prader-Willi syndromecoeliac disease or inflammatory bowel disease, there are organisations to support you.

More information about short stature

Growth in children

  • A child’s height depends on their genetic potential as well as general health and nutrition.
  • The commonest causes for short stature are normal variants – familial short stature and constitutional delay of growth and development.
  • Illnesses which can be occult like coeliac disease, poor nutrition during childhood or being small or premature at birth may mean children do not reach their full potential adult height.
  • A poor growth velocity (defined as being <25th percentile over a minimum of 6 months) is the most sensitive indicator of an underlying growth problem: any adverse event can cause a reduced growth velocity (including psychological abuse/ isolation, malnutrition, occult illness etc).
  • A poor growth velocity is non-specific and requires extensive investigation
  • Growth velocity can be difficult to interpret in late childhood due to the variable onset of puberty, which causes growth acceleration.

Red flags

  • A child who is very short (consider if <5th percentile, all children under 3rd percentile)
  • A child who is growing too slowly compared with other children the same age, or crossing percentiles
  • A child with abnormal growth and dysmorphic features
  • Late puberty
    • In girls after 13 years
    • In boys after 14 years

Assessment

  1. Take a history
  • Birth weight and gestation
  • Medication
  • Family history including parental height and timing of puberty
  • Look at the child’s height in comparison with their parents by calculating the mid-parental height:
    • Boy: Centimetres: (father’s height + mother’s height + 13) / 2
    • Girl: Centimetres: (father’s height – 13 + mother’s height) / 2

Most children will fall within 8 cm either side of the mid-parental height when their growth is complete. 

  1. Examine child
  • Measure height (on a stadiometer if available) and plot on growth chart
  • If over 5 years use CDC Growth Chart        
  • If under 5 years use WHO Growth Chart
    • In children >2 years measure standing height.
    • In children <2 years measure supine length.
  • Calculate height velocity if previous measurements available and plot on growth chart 
    • Calculate height velocity in cm per year using accurate measurements of height.
    • Leave at least a 6-month interval between measurements (to account for seasonal variations in growth).
  • Assess pubertal status
  • Examine optic fundi and assess visual fields
     
  1. Investigations
  • Chronic illness screen
    • FBC, UEC, CRP, coeliac antibodies, calcium, phosphate, LFTs, urinalysis
  • Hormonal screen
    • TFTS (Free T4 and TSH)
    • Bone age x-ray
       
  1. Management

If none of the red flags apply, reassess child in 6 months using the same measuring equipment and refer if crossing centiles.

  1. Request

If red flags apply, request Paediatric Endocrine assessment.

From Auckland HealthPathways, NZ, 2018