A large aneurysm in an arterio-venous fistula for renal access in a pregnant young woman.

Pregnancy is known to increase the risk of aneurysm formation, likely by a combination of histological changes in vessel walls associated with the hormones of pregnancy and the haemodynamic changes to the circulation. To our knowledge this is the first case of a pregnant woman with a brachial-cephalic arterio-venous fistula (AVF) that had never been needled for haemodialysis, yet became hugely aneurysmal during her pregnancy.