Cryoconservation is one of the methods of biomaterial preservation, i.e. freezing and storage in liquid nitrogen at -196oC. Biochemical processes in cells stop at this temperature.
Embryo and sperm cryoconservation has been used in the area of assisted reproduction from 1984, when the first pregnancy was achieved after a frozen embryo transfer.
There are two techniques of cryoconservation: slow programmable freezing and vitrification.
The first one is not widely applied today, as small ice crystals formed after biomaterial thawing damage the structure of gametes and embryos.
Nova Clinic uses vitrification, i.e. superfast freezing to cryoconserve sperm, egg cells, and embryos. They use special substances, called cryoprotectors, which penetrate a cell and absorb water. After thawing a reverse process takes place - cryoprotectors liquefy.
Biomaterial cryoconservation is used
- if a patients undergoes a radio- or chemotherapy treatment course, or a difficult operation which may affect his sperm fertility;
- if a patient’s occupation is related to health/life risks or adverse factors like chemical substances, ionizing emission, high or low temperature;
- for an ART program (IUI, IVF, ICSI), when it is not possible to provide a sperm sample on the day of an egg retrieval;
- for genetic material preservation.
Moreover, sperm can be cryoconserved just for storage to be used in future.
The medical checks and tests to undergo before a sperm cryoconservation
- Semen analysis
- Cryotest (the tests is performed to evaluate the sperm quality after thawing)
- Blood test for HIV, syphilis, hepatitis B and C
- Blood tests for sexually transmitted infections (for an ART program)
- Blood test for antibodies to simple herpes virus (for an ART program)
How is sperm cryoconservation performed?
When a sperm sample is provided, the embryologists perform a sperm analysis. If the quality of the sperm sample is superior, the sample is frozen. If there are only few spermatozoa in the sperm sample, or it was collected through TESE, the biomaterial will be concentrated before cryoconservation.
The embryologists put cryoprotectors in the sperm sample. In 10 minutes it is distributed into special polypropylene tubes to be preserved. Then the tubes are put in containers with liquid nitrogen and preserved in a cryodepository. Each of the containers is labeled with the patient’s name, medical card number and the date of cryoconservation.
For the whole storage period the embryologists maintain the optimal storage conditions and make regular records of it in their special record books.
You can sign a three-year storage contract with Nova Clinic. When the term expires, you can prolong it.
If you have any questions, please, don’t hesitate to contact us by phone +7 (495) 22-111-88.