Maternal characteristics according to severity of obesity.

*Tests for no association were for continuous variables T-test and ANOVA (analysis of variance), for categorical variables test for trend based on Goodman and Kruskal's gamma statistics. In tests applied to the 3 obesity groups, reference women were excluded.Subjects with missing values: exercise, n = 38; gestational weight gain, n = 1781; paternal BMI, n = 1498. Missing for other variables, n* 无关联性检验的方法如下：连续变量采用t检验与方差分析（analysis of variance，ANOVA），分类变量采用基于古德曼-克鲁斯卡尔伽马统计量的趋势检验。在针对3个肥胖组开展的检验中，参照组女性被排除。存在缺失值的研究对象信息如下：运动情况，n=38；妊娠期体重增加，n=1781；父亲身体质量指数（Body Mass Index，BMI），n=1498。其余变量存在缺失值的样本量为n=