Hi.... Women with clinical characteristics consistent with a high risk of GDM like marked obesity, personal history of GDM, glycosuria, or a strong family history of diabetes should undergo glucose testing as soon as possible... If they are found not to have GDM at that initial screening, they should be retested between 24 and 28 weeks of gestation. Women of average risk should have testing undertaken at 24–28 weeks of gestation. ....