Development of a Modified 100-Gram Oral Glucose Tolerance Test for Diagnosis of Gestational Diabetes Mellitus and Its Diagnostic Accuracy
Pornpimol Ruangvutilert MD, PhD*, Piya Chaemsaithong MD*, Kasem Ruangrongmorakot MD**, Sujin Kanokpongsakdi MD*, Prasert Sunsaneevithayakul MD*
Affiliation : * Department of Obstetrics and Gynecology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand ** Department of Obstetrics and Gynecology, Faculty of Medicine, Srinakharinwirot University, Ongkharak, Nakornnayok, Thailand
Objective : To develop a modified 100-g oral glucose tolerance test (100-g OGTT) for the diagnosis of gestational diabetes
mellitus (GDM) in order to reduce the number of values needed for the test.
Materials and Methods : Patient charts of pregnant women who completed the 100-g OGTT test at the antenatal clinic, Siriraj
Hospital between 2005 and 2006 were reviewed. Cases diagnosed with GDM using standard 100-g OGTT were selected. In
non-GDM cases, the last 100-g OGTT test was selected. Diagnostic performances of each glucose value and two or three
values in various combinations were determined.
Results : One thousand seven hundred sixty three women completed GDM diagnosis throughout their pregnancy. Four
hundred three women had GDM while 1,360 subjects were non-GDM. Considering single glucose values, the highest level
of accuracy, and the best ROC curve were obtained from the value at 2 hours after glucose ingestion (2-h glucose value) with
93.00% accuracy and the area under the ROC curve of 0.961. The combination of 2-h glucose value with fasting plasma
glucose (FPG) showed 93.25% accuracy. FPG combined with 1-h and 2-h glucose values achieved 100% sensitivity with
92% accuracy.
Conclusion : FPG in combined with 1-h and 2-h glucose values is an interesting alternative for the diagnosis of GDM.
Keywords : Gestational diabetes mellitus, Modified oral glucose tolerance test
