Discussion and management of potential reproductive health sequelae of adolescent cancer are essential and challenging components of care for the multidisciplinary team. Despite this, research has been limited to specific experiences (e.g. sperm banking) or fertility-related concerns of adult survivors. This grounded theory study of 38 male and female survivors of adolescent cancer aged 16–30 years drew on in-depth single interviews to map the range of experiences of being advised that treatment might affect fertility. Strong support for being told at around diagnosis was found regardless of gender, age, incapacity or availability of fertility preservation services. Age and life stage appeared less significant for impact than the perceived level of threat to personal and social well-being. Women were more likely to achieve lower levels of comprehension about the physiological impact, to report later distress from lack of fertility preservation services and to revisit more frequently those decisions made by the few offered fertility preservation. Men found decision making about sperm banking straightforward on the whole and reported satisfaction with having the choice regardless of outcome. Findings suggest that young people can cope with this information alongside diagnosis especially when professional and parental support is proportionate to the particular impact on them.