Embryo Slow Freezing / Vitrification

  • Cryopreservation of embryos has greatly enhanced the pregnancy rate and cumulative conception rate possible for a couple following a single cycle of ovarian stimulation and IVF.
  • Possibility of avoiding fresh embryo transfer in stimulated cycles with a potential for ovarian hyperstimulaton syndrome.
  • Factors which jeopardize implantation like bleeding, unfavorable endometrium, polyps or extremely difficult embryo transfer
  • Women who are undergoing chemo or radio therapy
  • Excess embryo per cycle.


  • Vitrification is the Solidification of solution into a glassy vitrified state.
  • Vitrification of water inside cells can be achieved by :
  • Increasing the speed of temperature conduction. * Use of high concentration of cryoprotectant helps to bring extremly high viscosity during cooling.

Primary Benefits of Vitrificaiton

  1. Direct contact between cells / tissue and Liq.N2
  2. No ice crystallization
  3. Utilizes higher concentration of cyroprotectant that allows shorter exposure time to the cryoprotectant.
  4. Rapid vitrification / warming.
  5. Small volume used provides a significant increase in the cooling rate.
  6. Cooling rates from -15000 to 30000C / min
  7. Minimizes osmotic injuries
  8. Reduces the time of cryopreservation procedure (duration from 2 to 10 mins)
  9. Very simple protocols
  10. Eliminates the cost of expensive programmable freezing equipment.

Our Approach :

Embryo cryopreservation has become well established technology in assisted human reproduction. At our centre we preserve embryo at 2-8 cell stage and even at blastocyst stage either by conventional slow freezing or by vitrification.The major aim of embryo cryo preservation is to provide further possibilities for conception and fresh transfer. It also contributed to lowering the risk of severe OHSS.