Failure to thrive.

Failure to thrive refers to a condition in which infants and children fail to develop and grow normally, as indicated by their inability to achieve noted markers on medically-accepted weight and height growth charts. Failure to thrive may be organic or inorganic; in many children, the etiology is multifactorial. The onset of growth problems may be prenatal as a result of maternal substance abuse, most notably alcohol use resulting in fetal alcohol syndrome, or of maternal infection or undernutrition during pregnancy. Chromosome problems, such as Down syndrome and Turner syndrome, are also medical causes of failure to thrive. Other causes include gastrointestinal disease resulting in poor micronutrient intake, endocrine disease, kidney disease, and heart and lung disease, all of which may decrease a child's appetite and how they process food and thus impair growth. Small size in infants secondary to prematurity resolves by two to three years of age unless there are complications. Undernutrition during infancy or childhood can also cause failure to thrive; undernutrition may result from inadequate protein and energy intake due to food insecurity and poverty, breastfeeding difficulties, or child neglect or abuse.