Cryopreservation is a process where cells or tissues are cooled to sub-zero temperature in order to preserve it for the future. Many times more than one embryo is formed during an IVF procedure. Embryo cryopreservation is done to preserve these excess embryos by freezing them to be used in future if the need be. This process is successfully in implementation over 30 years and the first pregnancy from frozen thawed embryos was conducted 1983. Till now, a quarter of a million babies have been born that follows cryopreservation and the technology has established a routine procedure.
In the Conventional IVF treatment protocols, during each cycle, more than three eggs can be collected and excess embryos can be frozen, and they can be put to use in future cycles.
Cryopreservation can be performed by cooling the tissue to sub zero temperatures, such as -196 degrees. It is usual to see that enzymatic activity and biochemical reactions which occur in a cell do cause damage to the material and at this low temperature, the damage is effectively stopped.
Two Basic Cryopreservation Techniques Developed:
Controlled Slow Rate Cooling Protocol
This protocol involves a high concentration of cryoprotectant is used and the entire process of cooling is done at a very slow rate. Embryos can be frozen by using this protocol of cryopreservation on Day 2 & Day 3.
Ultra-Rapid Flash Freezing Protocol
This protocol is also known as Vitrification. It this procedure also high concentration of cryoprotectant is used. The cooling process is done at a very fast rate. The embryos so formed are directly put into liquid nitrogen. By making use of this protocol cryopreservation of Day 2, Day 3, embryos and cryopreservation of eggs and Blastocysts can be done.
In the slow freezing process which is the conventional technique, may fail to prevent water content in the cells from ice crystal formation. And Embryos get damaged and lose their viability in case of crystal formation.
In the vitrification process, the cells free rapidly and it prevents the formation of intracellular ice. Thus it avoids cell damage.
In contrast, the vitrification process improves post-thaw embryo survival to over and above 90 percent, while slow freezing yields a survival rate for embryos of about 75-80 percent.
- Storage of embryos: In this Cryopreservation, patient can set the limit to the number of embryos transferred fresh without removal of unused embryos, which can be used for future pregnancy. These embryos can be stored for many years.
- Avoidance of Medications: Patients will not require further medication to stimulate the ovary because Cryopreserved embryos can be used in the next cycle of IVF.
- Lower Cost: Preservation of embryos allows doctors to avoid the preparation of new embryo and the cost of the procedure is always less when compared to fresh embryo transfer cycle.
Hegde Hospital has the best of the cryopreservation program in place. To know more about it, contact our Hospital. To book an appointment, call us at +91 8880 74 74 74