Fertility issues in survivors from adolescent cancers.

Infertility is a common and distressing late-effect of cancer treatment. Whist sperm banking for post-pubertal males and embryo freezing for women (who are in a stable relationship at the time of treatment) are highly successful fertility preservation strategies, for females without a partner (including young and pre-pubescent girls) and pre-pubescent boys (or azoospermic men), there remain no effective approaches. Whilst the biological effects of cancer treatments on the reproductive system are well described, there are few data on the relative incidence of infertility (failure to conceive after one year of trying) in cancer survivors. This makes it difficult to advise survivors about their future fertility prospects. Whilst some will undoubtedly conceive naturally with their partner, others will require assisted conception treatment of which in vitro fertilisation (IVF) and intra-cytoplasmic sperm injection (ICSI) are the most common. Pregnancy outcomes of cancer survivors are generally good, although there is increased risk of pre-term birth and low birth-weight in the offspring of women who have received pelvic irradiation. There is no increased incidence of genetic disease or cancer incidence in the offspring of cancer survivors. Current research directions are focussing on alternative fertility preservation strategies including in vitro maturation techniques, xenotransplantation and the development of technology to create artificial gametes in the laboratory. Finally, although the reproductive techniques discussed are highly effective, country specific differences in the legal framework means that cancer survivors may be denied access to certain treatments (e.g. embryo cryopreservation) because they are forbidden by specific national legislation.