A direct comparison of the measurement of a random plasma glucose and a post-50 g glucose load glucose, in the detection of gestational diabetes.

We have compared the use of a random plasma glucose measured within 2 hours of a meal and a plasma glucose measured 1 hour after a 50 g glucose load to detect pregnant patients likely to have an abnormal 100 g glucose tolerance test at 28 weeks' gestation. The 50 g glucose load detected 24 of 28 women with gestational diabetes whereas the random plasma glucose detected only 13 of these patients. The 50 g glucose load gave fewer false positives, that is, patients who had an abnormal screening test but went on to have a normal glucose tolerance test (8.8% versus 13.4%). These data support the use of the 50 g glucose load to screen pregnant women for gestational diabetes as recommended by Australian authorities (1).