Table 2—

Diagnosis of GDM by an oral glucose tolerance test

Oral glucose load*
100-g glucose75-g glucose
Fasting95 mg/dl5.3 mmol/l95 mg/dl5.3 mmol/l
1-h180 mg/dl10.0 mmol/l180 mg/dl10.0 mmol/l
2-h155 mg/dl8.6 mmol/l155 mg/dl8.6 mmol/l
3-h140 mg/dl7.8 mmol/l
  • Data are from Metzger et al. (9).

  • *

    * The test should be performed in the morning after an overnight fast of at least 8 h but not more than 14 h and after at least 3 days of unrestricted diet (≥150 g carbohydrate/day) and physical activity. The subject should remain seated and should not smoke throughout the test.

  • Two or more of the venous plasma glucose concentrations indicated below must be met or exceeded for a positive diagnosis.

  • The cutoff values are those proposed by Carpenter and Coustan (10) for extrapolation of the whole blood glucose values found by O'Sullivan and Mahan (11) to plasma glucose concentrations.