Paediatric medicine - Weight faltering and failure to thrive

Dr Kathryn Deakin and Professor Mary Rudolf look at a common cause for concern in young children.

Weight faltering is common in babies and toddlers and often causes concern for parents and professionals.

Although population studies indicate that the prognosis is generally good, the perception persists that poor weight gain causes long-term damage to the child, and anxiety is generated that in itself can be damaging.

As a result families can enter a vicious cycle where feeding becomes stressful and mealtimes become so unpleasant that aversion to food occurs.

An organic cause is found in a minority of cases. In others, neglect or even abuse is a factor, although this is far less common than previously thought.

The key to management is to identify medical problems causing or compounding poor weight gain, and to help parents manage eating difficulties, which are extremely common. Too often, the only action taken is to frequently monitor weight.

Credit: Simon Fraser / SPL

Accurate weight, height and head circumference should be charted

'Weight faltering' is the preferred term. 'Failure to thrive' is best reserved for those cases where there is not only poor weight gain but also a failure in psychosocial and emotional development - some argue that it should only be used where abuse or neglect are clearly identified as a cause.

Because one in six infants cross centiles in their first year, interpretation of growth patterns takes some skill. Criteria for growth patterns that merit assessment include a sustained fall through two centile spaces, height and weight below the second percentile, or a discrepancy of more than two centiles between height and weight.

Babies and toddlers
It is important that accurate measurements of weight, height and head circumference are obtained and plotted on a growth chart.

Babies born before 37 weeks gestation will be corrected for up to 12 months of age.

Although medical problems are an uncommon cause, their exclusion early on is important because it is difficult to provide effective input if there are anxieties about an underlying medical problem.

A full examination is needed including any dysmorphic signs and a neurodevelopmental assessment.

Children merit a paediatric referral when there are signs indicative of an organic problem, such as diarrhoea, vomiting, pallor, persistent respiratory symptoms, dysmorphic signs, congenital abnormalities or developmental delay.

On examination, wasting of the muscle bulk, a poor complexion, thin wispy hair and developmental delay are indications that health may be at risk.

Common conditions associated with, or responsible for, poor weight gain are shown in the box above right.

An important part of the assessment involves observing the child-parent interaction and sympathetically gaining an idea of diet and eating difficulties. Detailed recall of food eaten through the day should elicit whether nutrient intake is sufficient, whether there is a structured pattern to meals and whether the child is aversive to eating. It may also be helpful to ask the family to keep a diet diary for three days.

Children too often have unnecessary investigations in the pursuit of a diagnosis. An FBC is helpful, however, because toddlers often have a poor intake of iron-rich foods, especially where eating difficulties exist, making iron deficiency common.

Once a medical diagnosis has been excluded the aim is to try to resolve any eating difficulties - often advice focuses on increasing calorie intake alone.

It is also useful to ask a health visitor to arrange to observe a mealtime. This can provide valuable information as a basis for advice and reassurance. A positive approach is to encourage parents to make mealtimes an enjoyable experience rather than focus on food.

Referral routes for additional support include involving social services where there are social concerns or suspicion of neglect or abuse, speech therapy if there are concerns about oromotor skills, and a specialist nutrition team in areas where they exist.

Advising that the child attend nursery may be helpful as it provides support to the carer, a peer group to model eating behaviour and structured mealtimes.

The critical factors contributing to a positive outcome include an early thorough evaluation to exclude medical problems, and the identification of health, family and social factors that have contributed to the development of weight faltering.

Dr Deakin is specialist registrar in paediatrics at St James's University Hospital, Leeds and Professor Rudolf is consultant paediatrician and professor of child health at Leeds PCT and University of Leeds

Learning points

  • Faltering weight is a major cause of anxiety for families.
  • Weight faltering is not commonly due to neglect and organic causes are rare.
  • Eating difficulties are common and need addressing.
  • Family support, advice and reassurance is the mainstay of management.
  • Common conditions associated with faltering weight and growth

Inadequate intake

  • Insufficient calories
  • Loss of calories - vomiting or gastro-oesophageal reflux
  • Aversion to eating - oesophagitis
  • Delayed oromotor development - problems with chewing and swallowing lumpy food
  • Behavioural eating difficulties - food refusal, fussiness, distraction

Problems with absorption

  • Intolerance of cow's milk protein
  • Coeliac disease

Metabolic problems

  • Chronic disease
  • Congenital heart disease
  • Congenital hypothyroidism

Reduced growth potential

  • Intrauterine growth retardation/low birth weight
  • Familial short stature


  • Neurodevelopmental syndromes
  • Turner's syndrome
  • Fetal alcohol syndrome
  • Prader-Willi syndrome

Further reading

  1. Batchelor J, Kerslake A. Failure to Find Failure to Thrive. London: Whiting & Birch. 1990.
  2. Khan F, Rudolf M C J. Failure to thrive: Recognition and Management in Primary Care. Practical Paediatric Problems in Primary Care. Oxford: Oxford University Press. 2007: 135-48.
  3. Rudolf M C J, Logan S. What is the longterm outcome for children who fail to thrive?: a systematic review. Arch Dis Child 2005; 90: 925-31.

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins


Already registered?

Sign in

Follow Us:

Just published

Woman holding face in pain

Should GPs treat patients presenting with dental problems?

The MDU's Dr Kathryn Leask considers what GPs should do if a patient presents with...

Conservative Party leadership candidate and foreign secretary Liz Truss

Liz Truss vows to resolve GP pension tax crisis if she becomes prime minister

Liz Truss has affirmed her commitment to resolving the GP pensions crisis but has...

Baby receiving a vaccine in their thigh

JCVI advises changes to routine childhood and HPV immunisation schedules

The Joint Committee on Vaccination and Immunisation (JCVI) has recommended a change...

GP consultation

General practice delivering 'up to double the appointments it is paid for'

General practice in England may be delivering as many as double the number of appointments...

Sign outside BMA House

GP suicide sparks calls for measures to protect doctors from spiralling workloads

The government and policymakers must do more to safeguard doctors and NHS staff from...

Talking General Practice logo

Podcast: Living with long COVID

In August we’re bringing you some of the best interviews from series one of the podcast....