No study, however, has investigated neonatal growth in relation to breast cancer risk, even though neonatal growth could be of particular importance, as it is strongly associated with neonatal IGF-1 levels (Albertsson-Wikland et al, 1998; Ogilvy-Stuart et al, 1998; Hikino et al, 2001; Skalkidou et al, 2003). This evidence concerns the gene IGF1 and breast carcinoma.