Background:Gestational diabetes mellitus (GDM) is defined as the development of carbohydrate intolerance during pregnancy, excluding overt diabetes. GDM poses a risk of short-term adverse perinatal outcomes and long-term metabolic morbidity to women and their newborns.
Objectives:The aim of this study was to determine the role of first trimester glycosylated haemoglobin as a predictor of gestational diabetes mellitus.
Patients and methods: The study was carried out at Qena University Hospital, Department of Obstetrics and Gynecology.  The glcosylated hemoglobin investigation included 200 high risk pregnant ladies from the start trimester taking care of our outpatient facility and in tolerant from May 2019 to May 2020.
Results: Patients who developed gestational diabetes mellitus with HA1c < 5.7% were 12.4% while with HA1c ≥ 5.7% were 47.3%.  Also, there is significant statistically difference between both groups (p value= 0.015).ROC curve for HbA1c in 1st trimester as a predictor of gestational diabetes mellitus showed that the cut-off point was ≥6.2%, sensitivity was 93.3% and specificity was 90.0%.
Conclusion: The detection of glycosylated hemoglobin in the first trimester is a promising predictor biomarker for diagnosis of GDM and in the future may replace other basic investigations.