This paper reviews 1528 pregnancies in women with diabetes mellitus between 1968 and 1987 at National Women's Hospital; 571 had established diabetes and 957 had gestational diabetes. During this period the perinatal mortality rate for women with established diabetes fell from 15.2% to 2% and for those with gestational diabetes from 6.7% to 0.5%. This improvement was probably related to changes in management which included a team approach to perinatal care and a concentration on lowering blood glucose levels during pregnancy. The outstanding problem is the high incidence of congenital abnormalities in women with established diabetes. Two to three percent of these pregnancies ended in a perinatal death due to congenital anomaly. Improved prepregnancy and early pregnancy blood glucose control must be the aim to reduce the congenital abnormality rate.