Background: Gestational diabetes mellitus (GDM) is defined as a varying degree of carbohydrate intolerance that is recognized or first onset during pregnancy. It is associated with several maternal complications, including hypertensive disorders, hydramnios, preterm labor, operative delivery, shoulder dystocia, and perineal injuries. Early screening and treatment of GDM during the antenatal period are crucial, as they significantly reduce the risk of adverse maternal and perinatal outcomes. In India, universal screening is preferred over selective screening to facilitate early detection and improve pregnancy management.The methods for screening GDM have been a subject of controversy, transitioning from selective to universal screening approaches. Current screening modalities include measuring plasma glucose levels, conducting glucose challenge tests, or performing oral glucose tolerance tests (OGTT). The OGTT is recognized as the gold standard for screening GDM, although it presents challenges due to its time-consuming, costly, and unpalatable nature Recent studies indicate that during pregnancy, HbA1c levels exhibit less biological variation and may be linked to GDM. Measuring mid-trimester HbA1c levels could potentially reduce the reliance on OGTT, with multiple studies showing a correlation between HbA1c levels and obstetrical complications such as macrosomia and birth injuries.Despite these findings, the current recommendations do not endorse the use of HbA1c as a standalone diagnostic test for GDM. Therefore, this study aims to evaluate the effectiveness of glycosylated hemoglobin in diagnosing GDM in combination with a 75 gm OGTT, as per DIPSI guidelines, and its association with adverse maternal and neonatal effects.