The study was done to determine the maternal and fetal outcome of pregnancies complicated by maternal diabetes either Gestational Diabetes Mellitus (GDM) or preexisting (type 1 or type 2) diabetes over a period from March 2011 to Feb 2013 in a tertiary care hospital, Varanasi. This is a retrospective audit of the maternal and fetal outcome of women who presented to the Sir Sundar Lal Hospital, Department of Obstetrics and Gynaecology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India from March 2011 to Feb 2013, with GDM or pre-existing type 1 or type 2 Diabetes with pregnancy. The audit group comprised 65 pregnancies (67 babies), of whom 27 had preexisting diabetes and 38 cases developed gestational diabetes. Pregnant women who were found to be diabetic preconceptionally or in the first trimester were classified as 'pre-existing diabetes'. There were total of 65 diabetic women in this retrospective study, 39 women were GDM (60%) while 26 women (40%) were having pre-existing diabetes (24 type 1 diabetes and 2 women were in type 2 diabetes group). There were 35 multigravid women (53.85%) and 30 primigravid women (46.15%). There were 39 (60%) women on Insulin. There were 42 Lower Segment Caesarean Section (64.62%) and 23 Spontaneous Vaginal Delivery (35.38%). In fetal and neonatal complications, there were three still births, one case of intrapartum death, and one case of shoulder dystocia. Fetal anomalies were less frequent, one case of Gastroschisis with Hydrocephalus associated with Menigomyelocoele, there was one case of isolated Hydrocephalus, and there was also one case of Truncus arteriosus. The study analyses maternal and fetal complication in the GDM group and also preexisting diabetes group. In our centre, the 60% women were GDM while 40% were having pre-existing diabetes. Total rate of fetal/neonatal complication rate was 7.69% and of congenital anomaly rate it was 9.23%. Proportion of still birth, Intrauterine death, and congenital malformations was higher in the pre-existing diabetes group although the data are not large enough to draw a statistically significant conclusion. LSCS rate was little higher in the GDM group (69.23%) in comparison to the preexisting diabetes group where it was 57.69%. SVD (Spontaneous Vaginal Delivery) rate was 30.77% in GDM and 42.31% in the pre-existing diabetes group. HbA1c was within normal range 84.62% of GDM group while in 15.38% it was raised >6%. In the pre-existing diabetes group, only 19.23% of women had HbA1c within acceptable range and 80.77% had it >6. The aim of St Vincent Declaration is to 'achieve pregnancy outcome in the diabetic woman that is similar to that of the non-diabetic woman.' But, so far we have not been able to achieve this. Our HbA1c level is remarkably high in the pre-existing diabetes group. Only 3 out of 65 patients' women took Folic Acid periconceptionally. We need to work to achieve it our best. It is well known that insulin treatment during pregnancy results in reduction in the rate of macrosomia, fetal/neonatal, and maternal complications. Therefore, we need to use insulin judiciously and advocate its usage in the situations where it is needed.