This review is focussed on an update of the validity of ‘Metabolic programming’. The related concepts of critical windows and thrifty phenotype are also analyzed. The present concept of intrauterine growth restriction (IUGR) with its varied entries is considered not only because of the importance of fetal growth assessment but also for the precision that has been given to the neonatal status assessment. Particularly the perinatal nutrition status is approached for an eventual relationship to late obesity. More recent long term studies from well defined prenatal growth positions are analysed in terms of the mentioned programming hypothesis for later health. Finally it is considered how other circumstances such as certain polymorphisms of different genes are related to the developing of obesity.