Growth hormone (GH) concentrations were measured in cord serum of small (< 2.4 kg), appropriate (3.4 ± 0.1 kg) and large (> 4.4 kg) infants born at term (38–42 weeks), and in cord serum of prematurely born twins (28–36 weeks) which were either appropriate ( > P10) or small ( < P10) for gestational age. Cord serum GH levels were found to be significantly elevated in small for gestational age infants, both at term and preterm birth. In view of the insulin-antagonizing action of fetal GH, these results further support a homeostatic function for GH in the late-gestational human fetus.