Our understanding of the hormonal control of growth during the fetal period is incomplete, and it is inapparent how the short stature associated with intrauterine growth retardation (IUGR) might be prevented or treated, There is evidence that insulin-like growth factors (IGFs) play important roles in the regulation of perinatal growth, Ro dents genetically engineered to lack either IGFs or IGF receptors display prenatal and postnatal growth retardation, depending on the specific gene affected, Humans with IUGR frequently have low concentrations of IGF-I. Because some patients with IUGR associated short stature may have relatively decreased growth hormone (GH) secretion, GH treatment could be beneficial. Recent reports show gains in height for some patients when GH treatment is continuous and at a moderately high dosage. Patients with laboratory evidence for relatively lower GH secretion seem to respond better, These published studies, however, lack untreated controls and evaluate a paucity of patients treated to final height. Challenges for the future include the development of better methods of predicting who may respond to GH therapy, increasing our understanding of the mechanisms that control human growth in the perinatal period, and conducting well controlled studies that will determine whether GH treatment of patients with IUGR-associated short stature will produce meaningful gains in adult height.