Prevalence of gestational diabetes mellitus and associated risk factors in pregnant Chinese women: a cross-sectional study in Huangdao, Qingdao, China.

Background and Objectives: This study explored the prevalence of gestational diabetes mellitus (GDM) in Chinese pregnant women and identified risk factors for GDM after the implementation of the universal two-child policy. Methods and Study Design: On the basis of income and population, we randomly selected three hospitals through stratified and cluster sampling. From January 1 to July 31, 2016, 4959 women who had been registered within 12 weeks of gestation received a 75-g 2-h oral glucose tolerance test (OGTT) at 24-28 gestational weeks. International Association of Diabetes and Pregnancy Study Group criteria were used for the diagnosis of GDM. Results: The OGTT was positive in 1080 (21.8%; 1080/4959) women, who were then diagnosed as having GDM on the basis of their results. GDM was positively associated with the following factors: advanced maternal age (p < 0.001; adjusted odds ratio [OR] = 4.88; 95% confidence interval [CI] = 2.38-10.0, pre-pregnancy body mass index overweight (OR = 2.44, 95% CI = 1.78-3.34)/obesity (OR = 10.9, 95% CI = 6-19.6; p < 0.001), paternal history of diabetes (p = 0.003; OR = 2.54, 95% CI = 1.38-4.67), and maternal history of diabetes (p < 0.001; OR = 3.6, 95% CI= 2.16-5.98). Conclusions: Qingdao has an exceptionally high estimated prevalence of GDM. Widely recognized risk factors for GDM were advanced age, pre-pregnancy overweight/obesity, and a family history of diabetes in first-degree relatives. More options to prevent and manage GDM must be explored.