Ovarian Tissue Cryopreservation and Subsequent Auto-Transplantation for Female Cancer Patients

Inclusion Criteria: * Patients aged from 0-35 years old and diagnosed with cancer e.g., leukaemia, myeloproliferative or myelodysplastic diseases, lymphoma, bone tumours, neurological neoplasms and sarcoma, Paediatric bone marrow transplant patients * Patients with any illness or who will undergo any type of treatment that may cause irreversible damage to their fertility, such as extensive abdominal surgery, high toxicity medication and treatments; * Patients suffering from hormone-sensitive malignancies who will undergo medical treatment, such as radiotherapy and chemotherapy that is liable to damage their ovaries and deter them from conception in the future. Exclusion Criteria: * Patients with no anticipated oncologic therapies * Patients who are pregnant * Children with one ovary * Children deemed high risk for perioperative complications * Patients unable to provide consent/assent (i.e. significant psychiatric problems/cognitive delay)