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Failure to Thrive in Children


Christopher P. Raab

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Feb 2023 | Modified Mar 2023

Failure to thrive is a delay in weight gain and physical growth that can lead to delays in development and maturation.

  • Medical disorders and a lack of proper nutrition are causes of failure to thrive.

  • The diagnosis is based on a child's growth chart values, physical examination, health history, and home environment.

  • Children who are undernourished during the first year of life may have developmental delays.

  • Treatment includes a nutritious diet and treatment of medical disorders.

During the first year of life, an infant's weight and length are charted at each doctor's visit to make sure that growth is proceeding at a steady rate (see Physical Growth of Infants and Children Length and Height Physical growth refers to an increase in body size (length or height and weight) and in the size of organs. From birth to about age 1 or 2 years, children grow rapidly. After this rapid infant... read more ). Percentiles are a way of comparing infants of the same age and sex. For example, saying that an infant is at the 10th percentile for weight means that of 100 babies of the same age and sex, 90 weigh more and 10 weigh less. Although some infants are smaller and some are larger, infants typically stay at about the same percentile as they grow.

Failure to thrive is a diagnosis considered in children who are consistently underweight, typically below the 3rd to 5th percentiles, when compared to children of the same age and sex. Failure to thrive is also considered in infants who have a steady drop in their weight percentile even though their actual weight is not low. For example, doctors would be concerned about an infant who dropped from the 90th percentile to the 50th percentile (average weight) in a short period of time. There are many causes.

Causes of Failure to Thrive in Children

Causes of failure to thrive can involve

  • Environmental and social factors

  • Medical disorders

Environmental and social factors are the most common reasons why children do not get the nutrition they need. Failure to thrive for these reasons results from not taking in enough calories.

Sometimes parents provide food with poor nutritional value, which can lead to poor intake and poor weight gain. Parents may not fully understand infant feeding techniques and may improperly prepare formula, or the child may have feeding difficulties that the parents are unable to handle. When parents have poor infant feeding skills and their infant has feeding difficulties, failure to thrive may occur.

Rarely, some mothers do not produce enough breast milk or, rarer still, produce reduced-calorie breast milk.

Infants and children who have stressful family situations or have a dysfunctional relationship with a caregiver may have failure to thrive because the stress they are feeling may make them produce hormones that reduce the effects of growth hormones. This stress-related reduction in growth hormone can lead to poor growth.

Medical disorders sometimes cause failure to thrive. Medical disorders, such as difficulty chewing or swallowing (as with a cleft lip Cleft Lip and Cleft Palate A cleft is an opening that can form in the lip (cleft lip), roof of the mouth (cleft palate), or both if the tissue does not join together completely during pregnancy. Cleft lip and cleft palate... read more Cleft Lip and Cleft Palate or cleft palate Cleft Lip and Cleft Palate A cleft is an opening that can form in the lip (cleft lip), roof of the mouth (cleft palate), or both if the tissue does not join together completely during pregnancy. Cleft lip and cleft palate... read more Cleft Lip and Cleft Palate ), gastroesophageal reflux Gastroesophageal Reflux in Children Gastroesophageal reflux is the backward movement of food and acid from the stomach into the esophagus and sometimes into the mouth. Reflux may be caused by the infant’s position during feeding... read more , narrowing of the esophagus, or intestinal malabsorption Overview of Malabsorption Malabsorption syndrome refers to a number of disorders in which nutrients from food are not absorbed properly in the small intestine. Certain disorders, infections, and surgical procedures can... read more , may also affect a child's ability to eat, retain, absorb, or process food. Eating disorders Overview of Eating Disorders Eating disorders involve a disturbance of eating or of behavior related to eating, typically including Changes in what or how much people eat Measures people take to prevent food from being... read more may also cause failure to thrive.

Infections, tumors, hormonal or metabolic disorders (such as diabetes Diabetes Mellitus (DM) in Children and Adolescents Diabetes mellitus is a disorder in which blood sugar (glucose) levels are abnormally high because the body does not produce enough insulin or fails to respond normally to the insulin produced... read more Diabetes Mellitus (DM) in Children and Adolescents or cystic fibrosis Cystic Fibrosis (CF) Cystic fibrosis is a hereditary disease that causes certain glands to produce abnormally thick secretions, resulting in tissue and organ damage, especially in the lungs and the digestive tract... read more ), heart disease, kidney disease, liver disease, genetic disorders (such as Down syndrome Down Syndrome (Trisomy 21) Down syndrome is a chromosome disorder caused by an extra chromosome 21 that results in intellectual disability and physical abnormalities. Down syndrome is caused by an extra chromosome 21... read more Down Syndrome (Trisomy 21) or hereditary metabolic disorders Overview of Hereditary Metabolic Disorders Hereditary metabolic disorders are inherited genetic conditions that cause metabolism problems. Heredity is the passing of genes from one generation to the next. Children inherit their parents'... read more ), digestive disorders (such as celiac disease Celiac Disease Celiac disease is a hereditary intolerance to gluten (a protein found in wheat, barley, and rye) that causes characteristic changes in the lining of the small intestine, resulting in malabsorption... read more Celiac Disease and inflammatory bowel disease Overview of Inflammatory Bowel Disease (IBD) In inflammatory bowel diseases, the intestine (bowel) becomes inflamed, often causing recurring abdominal pain and diarrhea. The 2 primary types of inflammatory bowel disease (IBD) are Crohn... read more ), and human immunodeficiency virus (HIV) infection Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more are other medical reasons for failure to thrive.

In some children, failure to thrive is caused by a combination of environmental and social factors and medical disorders. For example, children who have medical disorders also can have stressful home environments or dysfunctional relationships with caregivers. Likewise, children with failure to thrive caused by environmental and social factors can develop medical disorders.

Diagnosis of Failure to Thrive in Children

  • Monitoring of weight and height

  • Questions about feeding and medical, social, and family history

  • Laboratory tests if needed

Doctors consider a diagnosis of failure to thrive when a child's weight or weight gain is well below what it should be when compared with past measurements or standard height-weight charts (see Physical Growth of Infants and Children Physical Growth of Infants and Children Physical growth refers to an increase in body size (length or height and weight) and in the size of organs. From birth to about age 1 or 2 years, children grow rapidly. After this rapid infant... read more ). If failure to thrive affects an infant's weight severely enough, height and head (brain) growth rates are also affected.

To determine why a child may be failing to thrive, doctors ask parents specific questions about

  • Feeding

  • Bowel habits

  • The social, emotional, and financial stability of the family, which might affect the child's access to food

  • Illnesses that the child has had or that run in the family

The doctor examines the child, looking for signs of conditions that could explain the child's poor weight gain. The doctor makes decisions about doing blood, stool, and urine tests and x-rays based on this evaluation. More extensive testing is done if the doctor suspects an underlying disorder.

Treatment of Failure to Thrive in Children

  • Nutritious feedings or meals

  • Specific treatment for medical disorders

Treatment of failure to thrive depends on the cause. If a medical disorder is found, specific treatment for that disorder is given. Regardless of the cause, all children who have failure to thrive are given a nutritious diet that contains enough calories to promote growth and weight gain.

Mild to moderate failure to thrive is treated with nutritious, high-calorie feedings or meals given on a regular schedule. Parents may be counseled about family interactions that are damaging to the child and about financial and social resources available to them.

Severe failure to thrive is treated in the hospital where social workers, nutritionists, feeding specialists, psychiatrists, and other specialists work together to determine the most likely causes of the child's failure to thrive and the best approach to feeding.

Children whose failure to thrive is the result of abuse or neglect may need to be placed in foster care Foster Care Foster care is care provided for children whose families are temporarily unable to care for them. Guided by federal (national) laws, local government determines the process of arranging foster... read more . If they are returned to their biologic parents, the children's growth progress is monitored.

Prognosis for Failure to Thrive in Children

Because the first year of life is important for brain development, children who become undernourished during this time may fall permanently behind their peers, even if their physical growth improves.

In about half of these children, mental development, especially verbal and math skills, remains below normal. These children often have behavioral, social, and emotional problems.

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