DefinitionFailure 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.Alternative NamesGrowth failure; FTTCauses, incidence, and risk factorsInfants or children that fail to thrive seem to be dramatically smaller or shorter than other children the same age. Teenagers may have short statureor appear to lack the usual changes that occur at puberty. However, there is a wide variation in normal growth and development.In general, the rate of change in weight and height may be more important than the actual measurements.It is important to determine whether failure to thrive results from medical problems or factors in the environment, such as abuse or neglect.There are multiple medical caus