Sperm may be frozen prior to the treatment cycle in cases where harvesting difficulties are anticipated on the day of follicular puncture or in some cases of oligoastenozoospermia.
Patients with oncological conditions who are to undergo pelvic chemotherapy or radiotherapy will be required to freeze sperm prior to preserving fertility, which may be affected by the treatments.
Defrosting can affect sperm quality. This change will be all the more pronounced and the worse its characteristics at the moment of freezing.