This article aims to provide a detailed guide to identifying and understanding failure to thrive. Whilst it discusses organic causes of failure to thrive, the management of each medical condition is not covered in depth as notes on specific pathologies can be found elsewhere on this website. Rather, it is a discussion about failure to thrive itself as a presentation. 


The term 'cease to thrive' first appeared in Holt's first edition of "The Diseases of Infancy and Childhood" in 1897, and in the 10th edition of this textbook in 1933 the term 'fail to thrive' was used. The term became established in the early 20th Century, meaning when growth in infants and children was poor as a consequence of socioeconomic disadvantage and high burden of infection. 


Failure to thrive is difficult to define, as determining normal growth reliably for an individual child is problematic. Therefore, it is difficult to identify growth impairment that counfounds the diagnosis of growth faltering. 

The following broad definition could be applied to clinical practice: 

Failure to thrive is a description applied to children whose current weight or rate of weight gain is significantly below that of other children of similar age and sex. 

This dynamic definition is appropriate because failure to thrive represents a change over time and conditional weight gain describes the phenomenon of regression of the mean (the concept that small infants tend to move upwards through centiles and large infants tend to move downwards across centiles). 

The term is used to describe: 

1. Infants or young children with poor weight gain associated with undernutrition. 

2. More broadly for poor weight gain regardless of the underlying cause. 

Weight faltering and growth faltering are preferred terms used in the literature and are synonymous with failure to thrive. 

Weight/height decelerating across two or more major centile lines (using 5th, 10th, 25th, 50th, 75th, 90th and 95th centile lines) from birth to weight/length within the given age group can help clinicians to identify a child with failure to thrive. However, other criterion exist such as the Gomez criterion and the Waterlow criterion.

Protein energy malnutrition describes malnutrition amongst children from developing countries where severe forms of nutritional deprivation are still prevalent such as kwashiorkor and marasmus. In developed countries, child wellbeing and health has improved but failure to thrive still exists. 


Failure to thrive is recognised as a common problem but due to the many different criteria used to make a diagnosis, incidence rates are difficult to report and are inconsistent. 

  • 1-5% of hospital admissions in children under two years of age are due to growth concerns. 
  • It is estimated that 5-10% of children seen in primary care are growing sub-optimally. 
  • The key factors that differentiate developing and developed countries are the levels of maternal education, associated malnutrition with poverty and the burden of chronic infections (HIV and TB as co-factors). 



The common pathway for failure to thrive is an insufficient amount of usable nutrition to meet the demands of growth during childhood. 

Historically, causes have been divided into organic and non-organic, although due to the obvious potential for overlap there is increased recognition of subdivision via: 

1. Inadequate calorie intake 

2. Calorie absorption/retention deficit 

3. Excessive calorie requirements 

Some of the organic and non-organic pathologies that can contribute to failure to thrive are shown below.

Pathophysiological causes of failure to thrive


With a good history, it is usually possible to differentiate between the different causes of failure to thrive. 

1. History of the pregnancy 

  • Smoking and alcohol 
  • Illness in pregnancy 
  • Use of medications during pregancy 
  • Antenatal growth and ultrasound scan results 
  • Screening test results 

2. Feeding history 

  • Bottle-fed - easy to see exactly how much per feed 
  • Breast feeding -harder to test 
  • Ask how child is - is child content with feed, disinterested, dissatisfied or craving more. 
  • Frequency of wet and dirty nappies - specific reference to nature of stool. Although babies stools are highly variable (especially when breast-fed), chronic diarrhoea will result in failure to thrive. 
  • Intolerance to cow's milk protein and timing of weaning should be assessed. Deficits in weaning should also be identified. 
  • Coeliac disease classically presents after child has been weaned from liquids to solids containing gluten. 
  • Older children - try to determine calorie intake, details about certain food avoidances (food allergy), or avoidance of foods of certain texture or colour (oromotor dysfunction or Autistic spectrum disorder) 
  • Any dietary restrictions (for example, strict vegetarianism or parental perceived food allergy) should be asked about.  

3. Past medical history 

  • Enquiring about all the systems to rule out major organic abnormalities which may cause failure to thrive 

4. Developmental history 

  • It is essential to take a thorough behavioural and developmental history. Children with growth problems can have developmental problems and the same can be said vice versa. 

5. Family history 

  • Anthropometric indices of parents and siblings for comparison 
  • Presence of any significant illnesses that run in the family may provide information about a cause for failure to thrive. 

6. Psychosocial history 

  • Family composition 
  • Employment 
  • Financial status 
  • Information about benefits 
  • Presence of physical or mental illness 
  • Substance abuse 
  • Domestic abuse
  • Post-natal depression

7. Information from other health workers - communication with community midwife, health visitor, dietician, GP and other local services are essential. 


    Note how the mother interacts with the child. Is she caring and concerned or cold and distant? In psychosocial failure to thrive, the amount of time the mother holds, talks to and plays with the child is often decreased. 

    1. Determine growth parameters: height, weight, head circumference, weight for height. These should be plotted on the appropriate growth charts. Adjust for prematurity before 37 weeks up to the age of 2 years. The growth velocity is useful in sepearating nutritional and endocrinological causes of failure to thrive.

    The link above will take you to the UK-WHO growth charts, which are important both for the diagnosis of failure to thrive and to understand tracking child progress and OSCE examinations.  

    2. Full systemic examination - clinical signs of malnutrition include: 

    • Pallid, dry, cracked skin 
    • Sparce hair growth 
    • Poor muscle development 
    • Lack of subcutaneous fat 
    • Swollen abdomen 
    • Oedema 
    • Signs of vitamin deficiency 

    It is important to review all the systems to identify an organic aspect to failure to thrive. 

    3. Examine for dysmorphic features indicative of a particular syndrome. Check the mouth for cleft palate and perform a full neurodevelopmental evaluation. 

    4. Observation of feeding is crucial. You are observing for: 

    • Mechanics of feeding
    • Carer-child interaction  
    • Childs developmental stage 
    • A 3-day food diary may be useful for older children

    5. Examine for signs of abuse/neglect 

    Angry/depressed mother may well feed the baby with excessive force resulting in torn frenulum (frenulum linguae, frenulum labii superioris, frenulum labii inferioris) and aversion to feeding, apathy, no eye contact or postive interaction. 

    To aid the diagnosis, it is also helpful to consider the age of the child who has presented in order to narrow the differential diagnoses. 

    Certain aspects of the history and examination are red flags for a medical cause of failure to thrive. These are shown in the opposite figure. 

    Investigations and evaluations

    • Only 1.4% of laboratory investigations performed in the evaluation of children with failure to thrive are useful diagnostically
    • However, red flag signs warrant further investigation. Basic first line investigations are shown in the table opposite.

    Other investigations that may be indicated from the history and/or examination include:

    • Chromosomal analysis, in particular girls presenting with failure to thrive to rule out Turner's syndrome
    • Complement and immunoglobulin levels 
    • Urine for amino acids/organic acids, serum ammonia 
    • Blood gas analysis for metabolic disorders 
    • Imaging such as CT/MRI, echocardiography may be useful if guided by a clinical suspicion
    • HIV/hepatitis serology 
    • Complement levels 
    • Stool samples for parasites and ova 

    If no red flag signs or symptoms are present, proceed with evaluation and management of appropriate caloric intake. 



    A multi-disciplinary team approach is required. Referals to primary care can come from community midwives or health visitors and GPs should decide whether referral to secondary care is necessary. 

    - Rule out organic causes for poor growth. If underlying organic causes of disease are found, these should be managed appropriately for that condition. Specialist interventions may be necessary in this case and the appropriate secondary care teams should be referred to. 

    -Re-evaluation is important. The patient should be seen initially and invited back 3 months later to confirm expected growth trajectory, check any new signs and symptoms and provide reassurance to carers. Carers should always be given the opportunity to discuss their concerns. 

    The role of specialist input 

    Paediatrician - Only if there are signs of severe illness or severe weight faltering. Generally inpatient monitoring with failure to thrive is not recommended unless it is an extreme case. Hospitals are an unnatural place to assess mother-child interaction and feeding. There is also the added risk of a hospital acquired infection. 

    Dietician - For confirmed failure to thrive without medical features, specialist pediatric dieticians can be useful in most casues helping to: 

    - Assess the adequacy of current diet to supply essential nutrients 

    - Offer targeted advice about enhancing the diet 

    - Often advise effectively about the basic feeding behavioural problems 

    High energy supplements for weight faltering is not evidenced for use in older children as it doesn't seem to improve weight gain and may depress solid food intake, although they may be useful for younger children. 

    Social worker - Not required unless there are major social problems such as drug/alcohol abuse and/or direct evidence of abuse/neglect. Families may lack the resources required to nourish a child. Identificaiton of this is important because by involving social services, they can treat the case as 'children in need' and this enables families to access appropriate support. 

    Psychology - This is an indicated intervention if there is: 

    - Pronounced food refusal 

    - A very anxious or stressful meal time. 

    Mealtime video observation can form structured feedback and advice as well as helping parents to control the child's anxiety. 

    Early involvement of the health visitor; simple advice about suboptimal breastfeeding; and inappropriate weaning has been shown to be effective - 1 in 5 show improvement after initial dietary advice. 

    Strategies for increasing energy intake in children over 9 months


    • Three meals and two snacks each day 
    • Increase the variety and amount of food offered
    • Avoid excessive intake of juice and squash 
    • Keep milk intake below 500ml per day
    • Increase the energy density of usual foods (for example margarine, cream and adding cheese) 


    • Offer meals at regular intervals with other family members 
    • Limit meal times to 30 minutes 
    • Avoid meal time conflict 
    • Do not force feed 
    • Praise the child when food is eaten and ignore when the food isn't eaten
    • Try to eat at the same time as the child when possible

    Myths surrounding failure to thrive

    Some children can eat and still not grow - Food consumed will always be used for metabolism or growth. If parents report good intake with no sign of improved growth, this must reflect food being offered too rarely. 

    Everyone in my family is small - Most failure to thrive children are thin rather than short. Showing weight-for-height centile charts to parents may convey the message better. 

    They are tracking their centile line so they must be ok - even with severe failure to thrive, children will eventually stop falling through centiles and track a low centile and can do so for months/years. It is not ok to be far away from the true centile. 

    Better a child be too thin than too fat- A childs 'fatness' in infancy shows no correlation with fatness in adulthood whilst some evidence suggests that thinness in early infancy and childhood increases health risk in adults. 

    Fatty foods are bad for young children- For children <2, a low fat diet is not recommended, fat is the main source of energy in breast milk and young children have high energy needs and therefore a high fat diet is required. 

    Difficulties and barriers to implementing changes


    Early childhood is critical for development. The main concern is that failure to thrive could cause future short stature, adverse behavioural problems and cognitive deficiencies. 

    It is generally agreed that, on average, children with failure to thrive will be shorter, lighter and score lower on tests of psychomotor development but with only marginal effects on IQ. 

    Early identification and timely intervention is required to prevent the potential long term consequences of failure to thrive. 


    • Failure to thrive is a common presentation in primary care. 
    • It is key with failure to thrive to look at weight/height changes over time; in a child that is crossing centiles, failure to thrive should be suspected. 
    • This problem presents commonly and although there are a multitude of pathologies that are associated, it mostly presents in otherwise healthy children. 
    • Failure to thrive must be quickly identified and reversed due to the possibility of developmental delay and poor long term prognostic outcomes. 
    • The history and examination provides the majority of the diagnosis with investigations being implicated if medical red flags for failure to thrive are present. 
    • Causes of failure to thrive can be subdivided into organic and non-organic but also by inadequate calorie intake, calorie absorption/retention defect or excessive calorie requirement. It is important to remember that patients may have contributing organic and non-organic problems. 
    • A multi-disciplinary approach should be implemented most importantly involving the health visitors before considering any specialist referrals and dietary review often reveals problems that respond well to simple advice.
    • Medical causes for failure to thrive should be identified from the history, examination and investigations and treated appropriately. 

    Reference list

     S.Tuohy, P.Barnes, S.J.Allen Failure to thrive Paediatrics and Child Health 2008;18(10): 464-468

    I.Scholler, S.Nittur Understanding Failure To Thrive Paediatrics and Child Health 2012;22(10): 438-442. 

    S.Z.Cole, J.S.Lanham Failure to thrive: An Update American Academy of Family Physicians 2011;83(7): 829-834

    C.M. Wright Children who fail to thrive Current Paediatrics 2000;10: 191-195.

    B.Shields, I.Wacogne, C.M.Wright Weight faltering and failure to thrive in infancy and early childhood BMJ 2012;35:1-7


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