Fetal macrosomia: etiologic factors.

Fetal growth can be considered the outcome of an interaction between the genetic cause of growth and constraints provided by limitations on substrate availability (selected amino acids, free fatty acids, and mainly glucose). It should be noted that the majority of large infants are constitutionally large and do not require special intervention, which will result in adverse perinatal outcome. Efforts should be directed to the accelerated (pathologic) overgrown fetus and to methods of primary prevention of this abnormality by appropriate management approaches for the mother and fetus.