Gestational Diabetes mellitus is defined as carbohydrate intolerance of variable severity with onset or first diagnosis in pregnancy. Gestational diabetes mellitus is associated with increasing pregnancy and fetal morbidity and also increases the likelihood of subsequent diabetes in mother. The latest concept is to screen for GDM in the first trimester or first visit as the fetal beta cell recognizes and responds to maternal glycemic level as early as16th week of gestation. Indian women have a 11 fold increase in risk of developing glucose intolerance, so universal screening is needed