Abstract

Aim: This study is aimed to determine the efficacy of HbA1c as a predictor in early diagnosis of GDM.
Methods: A Prospective observational study was conducted at Geetanjali Medical College and Hospital, Udaipur from January 2020 to June 2021 in 106 pregnant patients with high risk factor for GDM attending antenatal OPD in the first trimester. Fasting blood glucose, HbA1c and all routine investigation at first trimester were performed. Patients with FBS >92 mg/dl or HbA1c was <6.5% in the first trimester were further evaluated in the second trimester for repeat HbA1c and 75gm 2hr DIPSI. In patients with HbA1c <6.5% and DIPSI value between 140-200 mg/dl were further subjected to 75 gm oral glucose tolerance test to confirm the diagnosis of GDM using WHO-2013 criteria.
Result: 91 out of the 106 antenatal patients were diagnosed with GDM based on WHO 2013 criteria. Keeping the cut off 5.5% for HbA1c, sensitivity of 90%, specificity of 80%, negative predictive value of 90.9% and positive predictive value of 94.7% was calculated for the prediction of GDM. The area under the curve of HbA1c in early pregnancy to predict GDM was 0.84.
Conclusion: This study provides positive correlation between first trimester HbA1c >5.5%, second trimester DIPSI and OGTT positive cases.