Objective To explore the long term effects of gestational diabetes mellitus (GDM)on offsprings of affected women.Methods One hundred and twenty-four singleton pregnant women with GDM,who delivered in Department of Obstetrics and Gynecology,Peking University First Hospital from June 14,2006 to December 31,2007,were enrolled as the study group.Ninety-eight singleton pregnant women with normal glucose metabolism who delivered at the corresponding period were enrolled as the control group.The follow-up study was performed from November 6,2010 to January 31,2011 on their offsprings.Anthropometry indexes,including height,weight,waist circumference,systolic and diastolic blood pressure (DBP),triceps skin fold (TSF) and sub-scapular skin fold (SSF) were measured.According to the development standard of children less than five years old issued by World Health Organization in 2006,there were six detailed evaluation indicators including length/height for age z-score (HAZ),weight for age z-score (WAZ),weight for length/ height z score (WHZ),body mass index (BMI) for age z-score (BAZ),triceps skin folds for agez-score (TSFZ) and sub-scapular skin folds for age z-score (SSFZ).Chi-square,t-test or variance analysis were applied.Results (1) No statistical difference on age,birth weight,sex,height,weight,BMI,waist circumference,blood pressure,TSF and SSF was found between offsprings of study and control group (P＞0.05).(2) Offsprings in both groups were further divided into macrosomia and non-microsomia subgroups,i.e.GDM macrosomic subgroup (n =15),GDM nonmacrosomic subgroup (n=109),control macrosomia subgroup (n=6) and control non-macrosomia subgroup (n=92).Significant difference was shown amont the four subgroups in weight [(19.8±3.9),(17.0±1.9),(17.7±1.7)and (17.2±1.7) kg,F=6.238,P＜0.001],BMI (17.6±2.6,16.0±1.2,16.6±1.1 and 16.2±1.1,F=5.901,P＜0.001),waist circumference [(53.6±5.3),(49.9±2.7),(50.9±3.3) and (50.4±0.9) cm,F=5.307,P＜0.001],WHZ (1.40±1.44,0.45±0.81,0.88±0.75 and 0,60±0.87,F=5.269,P=0.002),HAZ (1.22±0.78,0.47±0.82,0.98±0.74 and 0.50±1.00,F=3.668,P=0.013),WAZ (1.68±1.23,0.58±0.79,1.15±0.85and 0.71±0.93,F=7.361,P＜0.001) and BAZ (1.41±1.52,0.42±0.84,0.81±0.76 and 0.60±0.90,F=5.210,P =0.002).While comparing between each two subgroups,there was statistical difference between GDM macrosomia subgroup and GDM non macrosomia subgroup,and between GDM marosomia subgroup and control non-macrosomia group.(3) While comparing GDM macrosomia and GDM non-macrosomia subgroup with control group [weight (17.2±2.5) kg,BMI (16.2± 1.4),waist circumference (50.5 ± 3.6) cm,DBP (55.2 ± 6.9)mm Hg,SSF(6.1 ± 1.8) mm,WHZ (0.62±0.87),HAZ (0.53±0.99),WAZ (0.73±0.92),BAZ(0.61±0.89)],the weight (F=9.283,P＜0.001),BMI (F=8.707,P＜0.001),waist circumference (F=7.934,P＜0.001),DBP(F=3.123,P=0.046),SSF (F=3.499,P=0.032),WHZ (F=7.639,P＜0.001),HAZ(F=4.709,P=0.010),WAZ (F=10.302,P＜0.001) and BAZ (F=7.689,P＜0.001) was higher in GDM group than the control group.(4) The proportions of overweight and obesity were higher in GDM macrosomia subgroup than in GDM non-macrosomia and control groups [overweight:9/15 vs24.8％ (27/109) and 24.5％ (24/98),x2 =8.870,P=0.012; obesity:5/15 vs 7.3％(8/109) and 9.2％(9/98),x2=10.083,P=0.006].If all subjects were divided into macrosomia and non-macrosomia group,then the proportion of overweight and obesity was higher in the former group [overweight:52.4％ (11/21) vs24.4％(49/201),x2=7.560,P=0.006; obesity:28.6％ (6/21)vs 7.9％(16/201),x2 =9.047,P=0.003].Conclusions GDM may have long term adverse effect on the development of offsprings at three-four-year-old with higher incidence of obesity or high diastolic blood pressure in macrosomic babies of GDM mothers than in non macrosomic babies of GDM mothers or babies of non GDM mothers.