Since the prevalence of gestational diabetes melitus (GDM) increased by ..., as an important part of medical treatment, nutrition therapy is highly required to help patients achieve normoglycemia. Carbohydrate intake is the primary nutrient affecting postprandial glucose levels,therefore the total amount and type of carbohydrate should be manipulated to blunt postprandial hyperglycemia. However,the type of carbohydrate has not yet been established. Rice and wheaten food have similar Glycemic Index (GI),but some researches found the glucose response to them is different. A case-control study is designed to compare the glucose control status between rice-richen meal and wheaten-richen meal, and all other macronutrients and micronutrients are all calculated and same between two groups, which may provide more clues for type of carbohydrate recommendation for Chinese women with GDM.

Inclusion Criteria:

• Pregnant women who undergo health examination in obstetric department in Peking Union Medical College Hospital.
• 20-45 years old.
• Pregnant women who are diagnosed with GDM according to the American College of Obstetricians and Gynecologists (ACOG) diagnostic criteria during 24-28 weeks.
• Be ability to use mobile medical equipment, conditional follow-up of the mother and child.
• Voluntary participation in this study.

Exclusion Criteria:

• Multiple pregnancy.
• Merger of serious diseases (such as hypertension, respiratory diseases, kidney disease, abnormal coagulation, immune system diseases, infectious diseases), history of adverse pregnancy (such as spontaneous abortion, habitual abortion), and history of GDM.
• Pregnant women with known diabetes before pregnancy, those requiring insulin or hormone therapy.
• Pregnant women who are deemed inappropriate to participate in this clinical study by her physician.

Study participants will be recruited from pregnant women who undergo health examination in Peking Union Medical College Hospital and meet the inclusion criteria.