Our results showed a positive correlation between SGA newborns and PAI-I deficiency (r = 0.74), current smoking status (r = 0.7), MTHFR A1298C homozygous (r = 0.69), MTHFR C677T homozygous (r = 0.65), antithrombin III (r = 0.66), and factor V Leiden (r = 0.53). This evidence concerns the gene MTHFR and hyperinsulinemic hypoglycemia, familial, 4.