Subfertility in children and young people treated for solid and haematological malignancies.

Children treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeutic agents have been identified as being gonadotoxic, and certain treatment regimens are particularly associated with subsequent infertility. Radiotherapy can also cause gonadal damage, most notably after direct testicular or pelvic irradiation or following total body irradiation. Because of the varied nature of the cytotoxic insult, it can be difficult to predict the likelihood of infertility in later life. Currently, cryopreservation of spermatozoa, oocytes or embryos is the only method of preserving fertility in patients receiving gonadotoxic therapy. This is only applicable to postpubertal patients and can be problematic in the adolescent age group. At present there is no provision for the prepubertal child, although there are a number of experimental methods being investigated. However, in addition to the many scientific and technical issues to be overcome before clinical application of such techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.