Failure to Thrive is defined in infants and children as a “physical sign of undernutrition, characterized by growth rates that do not meet expected standards for infants and toddlers under 3 years of age.”
Insufficient growth and undernutrition could be caused by either “organic” or “nonorganic” causes.
Nonorganic failure to thrive can be looked at as environmental in nature. This is primarily thought to be caused by the caregiver’s actions– not feeding the child appropriate amounts (unintentionally or intentionally), not recognizing the child’s hunger cues, not feeding enough during the day, insufficient breast milk production, parental neglect, and family relationship problems.
Organic failure to thrive has been associated with a chronic disease process or disability. These can be diseases that cause inadequate energy intake (Prader-Willi syndrome, GERD); inadequate nutrient absorption (celiac disease, cystic fibrosis, Bartter syndrome); increased metabolic demands (cerebral palsy, fetal alcohol syndrome, hyperthyroidism), or defective nutrient utilization (Cornelia de Lange syndrome, Inborn errors of metabolism, Down syndrome).
Failure to thrive could also be caused by a combination of organic and nonorganic factors– perhaps the child has GERD and gets upset during feeding times due to the pain of acid reflux. The parents may interpret that as a cue to stop the feeding, and thus the child could become underweight due to its diagnosis of GERD as well as the parents’ failure to provide enough energy and nutrition to the child.
Here’s an example of a growth chart: