Infants with a very low birth weight are at risk of a reduced number of nephrons predisposing to kidney disorder, hypertension, and metabolic syndrome. Approximately 3% of infants are born small for gestational age (SGA), defined as birth weight and/or length at least 2 SD below the mean for gestational age (GA), independently of whether these children are born prematurely or at term. About 10% of these children do not show postnatal catch-up growth and remain of short stature during childhood. Most of these infants are not growth hormone (GH)-deficient, but may have GH resistance. Although GH-resistant, the majority of patients benefit from GH therapy, normalize height during childhood, maintain a normal growth velocity during puberty, and attain a normal adult height. To date, GH has been shown to be safe and no significant adverse effects have been demonstrated. Children with congenital chronic kidney disease (CKD) are born with subnormal birth weight and length and about 25% are born SGA. Shortness and need for GH treatment is highly correlated with weight at birth and gestational age. Primary renal disorders modify the response to GH treatment. Analysis of whether SGA is an additional risk factor for CKD regarding the development of hypertension, metabolic syndrome and cardiovascular complications is required.