H Tournaye - Center for Reproductive Medicine, University Zieknhuis Brussel,Vrige Universiteit Brussel, Brussels, Belgium

Cytotoxic therapies and/or tes ticular irradiation are the maincause of germ cell loss and can hamper spermatogenesis permanently.These therapies are currently not only used to treatmalignant disorders, but also for benign haematological conditionsthat need bone-marrow transplantation. Hence, preservationof reproductive potential has become an important qualityof life issue in prepubertal boys and in adolescent and youngadults (AYA). In AYA, cryopreservation of sperm is possibleonce both spermarche and oigarche are a fact. Besides thesetwo prerequisites, counselling of AYA remains critical in a fertilitypreservation program. Prepubertal boys cannot benefitfrom sperm banking as active spermatogenesis is not present.As an alternative, tes ticular s tem cell banking is being introduced into more and more clinics as a preventive measure. Yet,this s trategy should s till be regarded as experimental given thelack of any report on successful transplantation. Therefore, alsohere counselling towards both child and parents is crucial