The placenta is formed as a result of the process of implantation, proliferation, and differentiation of the trophoblast; it is a vital organ for the survival, growth, and development of the embryo and fetus. The gestational diabetes mellitus is defined as abnormal or impaired glucose metabolism before pregnancy and it initially appears during pregnancy. A decrease in insulin sensitivity(increase insulin resistance) is normally seen during pregnancy to spare the glucose for the fetus.