Here are some unique advantages of the new Cryotec system over ALL other existing systems of Vitrification, including Sage:
- The solutions are improved with optimum viscosity to facilitate vitrification and warming.
- The solutions are stable for a year at 4-8c and stable for three months at RT.
- Trehalose has been used instead of Sucrose to eliminate the problem of endotoxins.
- The universal protocol for oocytes, embryos, and blastocysts makes the method very easy for embryologists.
- The new vitri and warm plates do not have any blind space in the wells, so it’s impossible to lose embryos/oocytes during washing.
- The plates have a Cryotec holder, so it has the same focus during loading and washing. The Cryotec has a long and wide handle, it has a big Cryotec mark for quick identification of the right side.
All these points add up and cumulatively aid in achieving 100% survival.
Nobody can give a 100% correct answer to this question, as the exact composition of most commercially available vitrification and warming media remains unknown. There are no extensive cross-examination studies done using all available vitrification and warming kits with human oocytes and embryos. But, in practice, we must remember the fact that warming methods are rather uniform. Since the warming media do not contain any intracellular cryoprotectant but only sucrose, any brand can be used for warming without any problem whatsoever, irrespective of the vitrifying solutions used.
Now with frequent cross-border cryoshipping of oocytes and embryos, many scientists have experienced equal success with embryos/oocytes vitrified using solutions of one brand, and warmed using another.
We recommend to use a pipette which inner diameter meets the diameter of the oocyte/embryo.
140-150 µm for oocyte and cleavage stage embryo.
160-200 µm for blastocyst
For best results you must adhere to the protocol. By using Vitri Plate and Warm Plate, you will minimize the stress on oocytes/embryos and will be able to achieve the good results.
The Vitrification Solutions must be tempered to 25-27°C atleast 1 hour before using.
The Warm plate and TS vial should be incubated at 37°C atleast 3 hrs before use (overnight incubation recommended). DS and WS must be tempered to 25-27°C atleast 1 hour before using.
The vitrification and warming process is to be done at RT.
Ideally 1 hour after denuding.
It is not necessary to collapse or shrink blastocysts. The best timing for vitrication of the blastocyst is when their size (diameter) is between 160-220µm for perfect survival after vitrification.
For vitrification, the solutions can be used 3 to 4 times, provided there is minimal transfer of solutions from one well to another. So, this really depends on the efficiency of the embryologist, in terms of handling and quickness. You will set your own limits as you move along the learning curve. For warming, it is recommended to use the solutions only once, since we transfer considerable volume of TS into DS, and DS into WS.
Maximum three cleavage stage embryos or oocytes can be loaded on cryotec. For blastocyst, we recommend a maximum of two.
Post warming wait for 2 hrs before microinjection (ICSI).
Day 2 and Day 3 embryo transfer can be done immediately after warming. In case of the blastocyst, the transfer should be done 2 hours after warming.
Assisted Hatching is not required as vitrification does not lead to zona hardening.
The best timing for vitrication of the blastocyst is when their size (diameter) is between 160-220µm for perfect survival after vitrification.
It is possible to achieve 100% survival vitrification provided you begin with normal cell quality and follow the strict protocol prescribed by Dr. Masashige Kuwayama
