Can we simplify the 100-g oral glucose tolerance test in pregnancy?

The aim of this study was to investigate if the omission of one of the glucose measurements in the 100-g oral glucose tolerance test (100-g OGTT) would have influenced the final diagnosis of GDM in a Brazilian cohort. We performed a retrospective study with 75 patients with GDM. The 100-g OGTT test was performed in 65 of these women. Twenty (30.76%), 24 (36.92%) and 21 (32.32%), respectively, had two, three and four values above the normal range. The mean fasting, 1, 2 and 3h glycemia were 109.81 +/- 33.34, 206.55 +/- 44.09, 188.13 +/- 46.52 and 142.12 +/- 49.53 mg/dl, respectively. They were above the cut-off values in 52 (80%), 55 (84.61%), 56 (86.1%) and 31 (47.6%) tests. The exclusion of the 1st, 2nd and 3rd measurements would have missed, respectively, 9 (10.5%), 16 (18.8%) and 13 (15.2%) cases. The omission of the 4th measurement would miss one case (1.17%). In conclusion, in our study, the omission of the last glucose measurement in the 3 h 100-g OGTT would not have caused a significant impact on the final diagnosis of GDM. Therefore, given the potential advantages of simplifying the test in terms of cost and convenience, the abbreviation of the 100-g OGTT should be considered.