Leak-proof polyester grafts impregnated with collagen, gelatine or albumin are routinely used in vascular surgery. Theoretically, there are several advantages: no need for pre-coagulation, reduced operation time and graft manipulation, less blood loss during the operative period, better healing with a potentially greater resistance to infection. We analyzed all the publications in scientific journals to verify whether these theoretical advantages are validated by clinical trials. There have been 12 non-comparative series reporting favourable results but the lack of control groups makes it difficult to draw conclusions. Five comparative series with random assignment of patients have been reported. None of these series showed a substantial benefit from impregnation. Thus the use of an impregnated polyester graft would not appear to be justified for routine standard aorto-iliac surgery. Conversely, although no evidence has been provided by a comparative study, the major risk of haemorrhage in procedures such as extra-corporal circulation, the thoracic or abdominal aorta and in patients with a coagulation disorder, impregnated graft probably constitute an important progress.