Two models of intrauterine growth restriction, maternal food restriction (FR) and dexamethasone (DEX) exposure were compared for early postnatal catch up growth and later development of glucose intolerance and obesity in Sprague-Dawley rats. Mated dams were randomly divided into three groups at 10 days gestational age. Group FR was food restricted (50% of controls) during the last 11 days of gestation; Group DEX received dexamethasone injections during the last week of gestation and Group CON, the control group, had no intervention. Birth weight, catch-up growth, body weight and food intake were measured in male offspring for 22 weeks. Body composition, blood glucose and plasma insulin in response to a glucose load were assessed at 8, 16 and 22 weeks. Pups from both FR and DEX dams had similarly lower birth weights than CON (- 20%, p<0.0001), but catch-up growth- which occurred during the suckling period - was much more rapid in FR than DEX offspring (6 vs 25 days, 95%CI). Post-weaning, there were no significant differences between-group in food intake, body weight, body fat and plasma insulin, but baseline plasma glucose at 22 weeks and 2-h glucose area-under-the-curve (AUC) at 8 and 22 weeks were greater only in FR vs CON offspring (P<0.05), thereby contrasting with the lack of significant differences between DEX vs CON. These results suggest that prenatal food restriction is a more sensitive model than dexamethasone exposure for studies aimed at investigating the link between low birth weight, early post-natal catch-up growth and later development of glucose intolerance.