What exactly is cryopreservation?

Cryopreservation is the process of storing or preserving living cells, tissues, and other biological samples in a deep freeze at subzero temperatures. The assay is usually held at-196°C.

The biological processes of the cells cease at such low temperatures, and the cell dies. Cryopreservation allows cells to withstand freezing and thawing.

The accumulation of ice within the cells has the potential to rupture the cell membrane. This can be avoided by controlling the freezing rate and carefully selecting the freezing medium.

Techniques of cryopreservation

Embryo cryopreservation

Hormones are used to promote egg production during infertility therapy. The eggs are then extracted and fertilized in the laboratory. More embryos can be formed and implanted in the uterus of a woman. These embryos may be cryopreserved and used in the future.

Sperm cryopreservation

This procedure increases the likelihood of possible reproduction. Sperm may also be deposited, frozen, and preserved in cryobanks for many years.

Cryopreservation of Oocytes

The oocyte is first put in a bath containing a low concentration of antifreeze like cryoprotectant. Sucrose is added to help pull water out of the shell. The egg is then placed in a high concentration antifreeze cryoprotectant for a few seconds before being immediately moved to liquid nitrogen. When the egg is thawed,IVF or ICSI is done and the resulting embryos can be transferred to the uterus of the female.


First, the woman would be given drugs to stimulate the production of several eggs. These eggs are harvested and allowed to fertilize with the sperms of the partner. Three or five days after fertilization, fertilized eggs or embryos are frozen.

As previously said, embryos are steadily frozen for two to four hours in the slow freezing process. Embryos are immediately immersed in liquid nitrogen at subzero temperatures during fast freezing.

The cryopreservation method has many advantages.
  • Surplus embryos can be cryopreserved .
  • Protection from the risk of hyperstimulation .
  • Ladies who want to delay child bearing due to career may freeze their eggs for future.
  • Biological samples may be stored for an extended period.
  • Better IVF results are seen with cryopreserved embryos.

There are certain things to consider while you are considering cryopreservation. Consult Dr. Ramya Mishra Shukla to see if cryopreservation is right for you.