Gestational diabetes (GDM) is defined as “carbohydrate intolerance of variable severity with onset or first recognition during pregnancy.” The definition is applicable regardless of whether insulin is used for treatment or the condition persists after pregnancy. It does not exclude the possibility that unrecognized glucose intolerance may have antedated the pregnancy”. GDM complicates 3–15% of all pregnancies and is a major cause of perinatal morbidity and mortality, as well as maternal long term morbidity. Of all types of diabetes, gestational diabetes (GDM) accounts for approximately 90–95% of all cases of diabetes in pregnancy.