Abstract： Objective To explore the adverse effect of abnormal metabolism of glucose during gestation on pregnant outcomes of pregnant women and peripartum babies. Methods 10 809 pregnant women at gestational age of 24～28 weeks were screened with 50g glucose challenge test (GCT), and subjects with a positive reaction would receive further 75g oral glucose tolerance test (OGTT).Based on the results of OGTT, they were divided into three groups: normal glucose tolerance(GNGT), gestational diabetes mellitus (GDM), and gestational impaired glucose tolerance (GIGT). Results Of 10 809 pregnant women, 66 women and 270 women were diagnosed as GDM (0.61%) and GIGT(2.5%), respectively.The incidences of postpartum hemorrhage, cesarean section, pregnancy-induced hypertension, polyhydramnios, fetal macrosomia, premature delivery, neonatal hypoglycemia were higher in GDM group than in GNGT group (P<0.05). The incidences of cesarean section, polyhydramnios and fetal acrosomia were higher in GIGT group than in GNGT group (P<0.05) .The incidence of low birth weight was lower in the GIGT group than in GNGT group (P<0.05) . Conclusions Abnormal metabolism of glucose in pregnancy can produce adverse impact on mothers and neonates.Therefore, it is very important to make detection, diagnosis and treatment for abnormality of glucose metabolism during pregnancy.