What is “failure to thrive?”

Failure to thrive” is the term used to describe children whose growth rate is significantly lower than that of other children of the same age and gender. While some children fail to meet expected growth standards, most follow a pattern of growth that is considered a normal variation. According to the the American Academy of Pediatrics, children who fail to thrive don't receive or cannot take in, keep, or use the calories that would help them grow and gain enough weight.

Most children double their birth weight by 4–6 months and triple it by 1 year of age. Children with failure to thrive may hit the first target, but miss the second. In some instances, weight, as well as height, is affected. Inadequate growth can also affect brain development and the ability for a child to reach certain developmental milestones at appropriate times in early childhood. A child’s brain grows to 80 percent of its adult size in the first three years of life. Poor growth during this time period can have lasting consequences. 

What causes failure to thrive? 

When children fail to meet expected growth standards, there are a variety of underlying problems that can keep them from getting the calories they need to grow. Breastfed infants may not be getting enough milk due to a rigid feeding schedule as opposed to being fed on request. Some children may need more food than their parents are able to provide. And some parents may restrict calories fearing their child will become obese.

Failure to thrive could also signal a medical problem. According to the AAP and National Institutes of Health (NIH), a number of things can cause failure to thrive: 

  • Not enough food offered. In some cases, parents mistakenly cause the problem. Sometimes a parent measures formula incorrectly, causing an infant to get too few calories. Problems with breastfeeding or transitioning to solids also can cause failure to thrive. 
  • The child eats too little. Some children have trouble eating enough food because of prematurity, developmental delays, or conditions like autism in which they do not like eating foods of certain textures or tastes.
  • Allergies
  • Food intolerance. This is different from a food allergy and means the body is sensitive to certain foods. For example, milk protein intolerance means the body can't absorb foods that have milk proteins, such as yogurt and cheese
  • Health problems involving the digestive system. Several health conditions can prevent a child from gaining weight. These include gastroesophageal reflux (GER), chronic diarrhea, cystic fibrosis, chronic liver disease, and celiac disease.
  • Metabolic disorders. Conditions such as cystic fibrosis, diabetes, or heart disease, can make it hard for the body to break down, process, or take energy from food. They also can cause a child to eat poorly or vomit.
  • An ongoing illness or disorder. A child who has trouble eating — because of prematurity or a cleft lip or palate, for example — may not take in enough calories to support normal growth. Other conditions involving the heart, lungs, or endocrine system can increase the amount of calories a child needs and make it hard for the child to eat enough to keep up.
  • Infections. Parasites, urinary tract infections (UTIs), tuberculosis, and other infections can force the body to use nutrients rapidly and decrease appetite.
  • Genetic diseases such as Down syndrome or Turner syndrome
  • Growth hormone or thyroid hormone deficiency 

How do I know if my child is failing to thrive? 

Children who are failing to thrive are typically much smaller or shorter than other children their age. Slow weight gain and short stature alone, however, are not an indication of failure to thrive. Many babies have periods of no weight gain; some may even lose a little weight from time to time. Failure to thrive typically describes babies under the age of 1 year who fail to gain weight for three consecutive months, or children whose weight is lower than the 3rd percentile or 20 percent below the ideal weight for their height. 

If your child is among those who double and triple their birth weight at later dates, perhaps 9 months and 18 months, don’t panic. Some children grow more slowly than others, and some never achieve the height that other children achieve given their genetic differences (it’s unlikely that short parents will produce tall children). 

The following symptoms may also be seen in a child that fails to thrive: 

  • Excessive crying 
  • Excessive sleepiness 
  • Irritability 
  • Poor feeding 
  • Avoids eye contact
  • Does not reach developmental milestones like sitting up, walking, and taking at the usual age

Failure to thrive must be diagnosed and treated early (ideally within three months). Delaying intervention could result in disruption to a child’s normal physical, mental, and emotional development, including gross motor skills (rolling over, sitting up, standing or walking).

What is the treatment for failure to thrive? 

A child’s health care provider must figure out exactly when a child’s weight gain or growth stopped in order to determine what is causing the failure to thrive. Once an underlying medical condition is ruled out, your child’s health care provider will consider emotional or social problems. 

In the case of a breastfed baby, if the mother has ample breast milk but her baby is underfed, the health care provider can share breastfeeding tips and techniques. If a mother’s milk supply is low, the health care provider may suggest that a mother pump her breasts and supplement with formula until her milk supply recovers and her child displays consistent weight gain. The American Academy of Pediatrics cautions that parents should not give their child dietary supplements without first consulting the child’s doctor, since there may be an underlying medical condition. If you think your child is not growing appropriately, contact his health care provider for a thorough evaluation. Sometimes, reassurance is the only treatment needed.

Last updated June 5, 2017

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