Gestational Diabetes Mellitus (GDM) refers to the abnormal glucose metabolism first detected during pregnancy. It is estimated that approximately 7% of pregnant women worldwide and their offspring are affected by GDM. The incidence of GDM in China is as high as 18.9%. A number of studies have shown that GDM complicates 3%-25% of pregnancies and poses serious health and life threats to the mother and child. In fact, due to the lack of physical activity during pregnancy and the decrease of insulin sensitivity compared with non-pregnancy, the optimal time for intervention has long been lost until the diagnosis of GDM in the second trimester. However, it is a pity that no authoritative screening method for GDM in early pregnancy has been established, and the pathogenesis of GDM is still unclear. This study intend to search for biomarkers used for screening of GDM in early pregnancy and explore the pathogenesis of GDM, so as to provide new ideas for prevention measures and treatment targets of GDM.

Inclusion Criteria:

• Maternal age: 20-49 years
• Plan to have routine prenatal examinations and give birth in the research center
• Willing to cooperate with the hospital to follow up

Exclusion Criteria:

• Have diseases that affect metabolic function or even threaten the life of the mother and fetus before pregnancy, such as diabetes, hypertension, heart disease, liver and kidney diseases, thyroid diseases, autoimmune diseases, malignant tumors, AIDS, etc.
• Fetus has a known deformity or genetic defects
• Incomplete clinical data

This project intends to recruit pregnant women who go to the research center for routine prenatal examination and OGTT screening.