Abstract:ObjectiveTo investigate the effect of life-style intervention in early and middle trimester of pregnancy on the incidence of gestational diabetes mellitus（GDM）.MethodsA total of 1 746 pregnant women (gestational age < 14 weeks) having antenatal examination and file in obstetric clinic of the People′s Hospital of Inner Mongolia Autonomous Region from August 2015 to February 2016 were selected and randomly divided into intensive group (n=1 164) and routine group (n=582).The routine obstetric management combined with life style intervention was performed in intensive group,while only routine obstetric management was given in routine group.All subjects underwent 75 g oral glucose tolerance test(OGTT) at 24-28 weeks of gestation,and the incidences of GDM were compared between two groups.ResultsThere were no significant differences in age,family history of diabetes mellitus,body mass index (BMI) before pregnancy,blood glucose and gestational age between two groups (P>0.05).The rate of loss to follow-up for 4-6 week was 29.90% (348/1 164) in intensive group and 1.20% (7/582) in routine group(P<0.01).Compared with routine group,the average daily calorie intake ［（1 598.46±208.68）kcal vs （1 974.15±337.42）kcal］ and the average weight gain ［（9.86±3.63）kg vs（10.64±5.40）kg］ significantly decreased and the exercise time each week［(134.38±30.70）min vs [JP2]（105.02±38.50）min］ increased in intensive group（P＜0.01）.There was no significant difference in the incidence of GDM between two groups (15.44% vs 16.00%,P>0.05),even though it was slightly lower in intensive group.ConclusionLife-style intervention in the early and middle trimester of pregnancy can not reduce the incidence of GDM.