Inclusion Criteria:

- Interventional Arm:

- Eligible for myeloablative allogenic or autologous hematopoietic cell transplant
(HCT)

- Post-menarchal female < or = 50 years of age

- Normal antimullerian hormone (AMH) level and/or follicle stimulating hormone
(FSH)/leuprolide (LH) levels for age/stage of puberty

- Those women who have an FSH > 40 IU/L and whose diagnosis of malignancy and
whose chemotherapy treatment was within 12 weeks of enrollment are still
eligible if they had normal menstrual cycles pre-diagnosis.

- Observational Arm:

- Eligible for reduced intensity allogeneic HCT

- Post-menarchal female ≤ 50 years of age

- Normal AMH level and/or FSH/LH for age/stage of puberty

- Those women who an FSH >40 IU/L and whose diagnosis of malignancy and
chemotherapy treatment was within 12 weeks of enrollment are still eligible if
they had normal menstrual cycles pre-diagnosis.

Exclusion Criteria:

- All Arms:

- History of ovarian cancer

- Surgical resection of one or both ovaries. Prior hysterectomy is allowed as long
as the ovaries are intact.

- Use of GnRH agonist in last 12 months will exclude patients if lab results are
not available to demonstrate adequate ovarian function prior to initiation of
GnRH therapy.