Ovarian Tissue Cryopreservation in Pre-Pubertal (OTC-Pre Pubertal)

Inclusion Criteria:

* Pre- Pubertal Individual
* Will undergo imminent surgery, chemotherapy or radiation therapy that has implications on future fertility and reproductive hormone potential: any health condition or malignancy that requires removal of all or part of one or both ovaries, whole abdomen or pelvic irradiation ≥10Gy in post-pubertal girls or ≥15Gy in pre-pubertal girls total body irradiation, and alkylating-intensive chemotherapy:
* cyclophosphamide cumulative dose ≥7.5 g/m2
* any treatment regimen containing procarbazine
* busulfan cumulative dose \>600 mg/m2
* alkylating chemotherapy conditioning prior to stem cell transplantation combination of any alkylating agent with total body irradiation or whole abdomen or pelvic radiation cranial radiation ≥30 Gy summed alkylating agent dose score ≥3 (Green et al., 2009) cyclophosphamide equivalent dose (CED) ≥ 4,000 mg/m2 (Green et al., 2014)

Exclusion Criteria:

* Patients with no anticipated oncologic therapies
* Post-pubertal individuals
* Pregnant children
* Children with one ovary
* Children deemed high risk for perioperative complications
* Patients unable to provide consent/assent (i.e. significant psychiatric problems/cognitive delay)