Diagnosis
In the Carpenter/Coustan conversion method, diagnosis of GDM is based on the presence of 2 or more of the following factors8,9:
Fasting serum glucose concentration exceeding 95 mg/dL
1-hour serum glucose concentration exceeding 180 mg/dL
2-hour serum glucose concentration exceeding 155 mg/dL
3-hour serum glucose concentration exceeding 140 mg/dL
Alternatively, some centers employ the National Diabetes Data Group (NDDG) criteria, which are slightly more liberal.10 The abnormal values are as follows:
Fasting serum glucose concentration exceeding 105 mg/dL
1-hour serum glucose concentration exceeding 190 mg/dL
2-hour serum glucose concentration exceeding 165 mg/dL
3-hour serum glucose concentration exceeding 145 mg/dL