Every semen sample is carefully identified using a special coding system and labeling, which ensures the precise traceability and confidentiality of the data. Each sample is labeled with the patient’s name, a unique code and the date of freezing.
A small aliquot of every semen sample is examined with regard to the basic sperm parameters before freezing, i.e.:
- Semen volume
- Sperm motility
- Motility index
The rest of the sample is diluted with a special cryoprotectant medium, which protects the biological properties of the spermatozoa during the freezing process.
The sample is gradually put in special freezing containers (straws or paillettes) at several aliquots of low volume (0.5 ml). The total number of straws depends on the total volume of the semen sample.
The freezing process starts directly after the straw filling and is performed using a semi-automated system which permits the gradual temperature decrease from room temperature to ultra low levels (< 0 °C). This step protects the spermatozoa from the damage that an abrupt temperature fall would cause.
At the end of the freezing cycle, the samples are submerged in liquid nitrogen and then placed in special long term cryopreservation tanks.
Semen may be preserved at a final temperature of -196 °C indefinitely. CRYOGONIA Sperm Bank offers semen cryopreservation for long time periods, following the patient’s consent and its renewal at regular intervals.
