What is cryopreservation?
Cryopreservation is a technique that allows the preservation of cells or tissues by rapidly cooling them to extremely low temperatures, up to -196°C, by immersing them in liquid nitrogen. Under these conditions, all biological activity is interrupted, including that related to cell death, and everything is “frozen” until there is warming again.
For sperm freezing, it is necessary to add a cryoprotectant that protects the sperm from sudden temperature changes. This mixture is then packaged in pre-identified straws with the patient’s name.
The number of straws frozen per ejaculate depends on the volume and quality of the sperm.
Although the freeze-thaw technique may result in partial mortality of the sperm, once frozen, these samples can be stored ad vitam aeternam without possible degradation over time. However, Belgian law imposes a maximum storage period of 10 years, which can be renewed annually once this period has passed.
For sperm freezing, it is necessary to provide:
- Serological results performed a maximum of 3 months before freezing (the blood test can be performed at our facility, two days before freezing).
- A medical prescription, except in case of urgent medical freezing (see below).
- A signed consent, usually given by the prescribing physician. If the prescribing physician is external to our ART center, the consent will be provided to you by the biologist on the day of freezing.