Sperm freezing is usually done in order to:
- adress the male factor infertility due to oligospermia
- treat the cases of difficulty in sperm production either due to absence or due to psychological burden on the day of oocyte retrieval,
- maintain sperm after testicular biopsy (TESE).
- preserve fertility in men who are undergoing chemotherapy.
In these cases, freezing the sample is carried out by using appropriate cryoprotective substances (cryoprotectants) which protect the sperm cells from the freezing process. The frozen sample can be kept and used for future IVF attempts without time limit.