According to the result, metformin ranked the best with the lowest incidence of macrosomia, 2HPG, LGA, and RDS; metformin plus insulin ranked the best regarding the risk of PIH, gestational age at delivery, weight gain, mean birth weight, and FBG; glyburide ranked the worst regarding the risk of macrosomia, preeclampsia, hyperbilirubinemia, neonatal hypoglycemia, and gestational age at delivery and mean birth weight, but ranked the best regarding the risk of NICU admission and HbA1C. This evidence concerns the gene INS and Large for gestational age.