Cryopreservation of oocytes has been proposed as a way of storing gametes in young patients at high risk of infertility and premature ovarian failure. Recent advances in cryobiology have yielded promising results, leading to oocyte cryopreservation becoming a mainstay of fertility preservation. In this case series, we describe the feasibility of performing ovarian stimulation, and the ethical challenges faced, in teenage girls, aged 14–18 years, prior to undergoing bone marrow transplant for sickle cell anaemia. All eight consecutive cases completed ovarian stimulation and oocyte retrieval with mature oocytes being found and cryopreserved for each patient. The mean dose of gonadotrophin stimulation was 2134.38 IU (95% CI 1593.34–2675.4) and the mean duration of treatment was 11 days (95% CI 10.02–11.98). The mean number of oocytes retrieved was 14.88 (95% CI 7.39–22.36), of which a mean of 12.13 (95% CI 4.72–19.54) oocytes were mature and cryopreserved. There was one case of moderate ovarian hyperstimulation syndrome that required hospital admission for supportive treatment. Oocyte cryopreservation is a technique that can be successfully employed after the retrieval of mature oocytes from the peripubertal ovary, restoring hope to these patients, and their families, of having their own genetic children in the future.