Cryotechnology Or Cryo Preservation Procedure
Embryo Freezing (CRYO-CRYOPRESERVATION)
What is Cryo?
Cryo is the method used to freeze and preserve the embryo (cellular structure formed with the fertilization of egg by sperm)
Who All Are Eligible?
When a number of good quality embryos are obtained during in vitro fertilization procedure, eggs that are not transferred shall be frozen and preserved. If needed, such embryos can be thawed and used for the next treatments. A minimum of 2 frozen eggs are required for such an attempt. Embryos that are frozen with a consent by couples can be preserved in liquid nitrogen for five years in accordance with the regulations in Turkey. In case of divorce or death of one of the spouses, the consent form for embryo freezing shall be considered terminated and embryos will be disposed.
What are the Advantages?
The Cryo procedure is economical. As we already have embryos available, ovarian stimulation with medication and re-retrieval of eggs will not be required. This will reduce the cost of treatment by half. This is less stressful for patients. There is no risk of failure to obtain eggs or embryos as well as stress for surgery. Patient’s adherence to the treatment is easy. Side effects of the treatment are less.
How Cryo Cycle is Administered?
The treatment requires use of tablets containing estrogen hormone. This hormone allows a healthy development of the intra uterine membrane where the embryo will be placed. When endometrium reaches the appropriate thickness, embryos will be thawed and transferred. The Cryo Cycle can also be applied during natural menstrual period in some patients.
Will Any Problem Be Confronted In Infants Born As A Result of the Cryo Cycle Procedure?
Studies revealed that babies born this way are not at risk for anomalies.
What is the Success Rate?
The present technology (vitrification) allows 95% of frozen embryos to be dissolved without any problems. Pregnancy rate is 30-40%.
There are two basic processes of cell cryo preservation; namely, freezing and thawing. The process of freezing consists of different steps and procedures that start with the successful placement of the embryo in different media of increasing osmolarity. The loss of water (dehydration) from the embryo that results from the external increased osmotic pressure leads to, among other things, a drop in the volume of the cell. After very fast dehydration, the embryo is then placed into liquid nitrogen by using the different methods of slow freezing or vitrification. Similarly, the process of thawing consists of a variety of steps. The first step is warming up the cell from the liquid nitrogen to room temperature. Re-hydration then occurs in steps, during which the embryo is moved into samples of media with decreased osmolarity and a lower concentration of cryo‐protectants. Each time, the volume of the embryo will increase because of water absorption. It will finally return to its normal size because of the concurrent outflow of cryo‐protectant. After re-hydration, the embryo is placed in a normal culture medium to continue growing.