Few studies explored the relationship between GDM and maternal obesity and found an increased prevalence of GDM among obese women compared to those of normal weight [6], in addition obese women who develop GDM needed insulin to reach the target blood glucose level compared to normal weight women who were controlled by diet alone [16] and that the combination of obesity and GDM was associated with the worse outcomes compared to each condition alone [17,18]. This evidence concerns the gene INS and obesity disorder.