29,832 IVF Pregnancies
Patients who undergo in vitro fertilisation (IVF) may produce several eggs (oocytes) which, if fertilisation takes place, will be developed into embryos. Very often and for very different reasons, one patient may need to freeze (cryopreserve) their oocytes or embryos. In the traditional cryopreservation methods (slow freezing), the formation of intracellular ice crystals can damage the structure of the cells decreasing their viability.
Vitrification is an advanced cryopreservation technique for oocytes and embryos that based on the nature of the cryo-protectants used and an extremely fast cooling rate is able to generate a glass-like state preventing the formation of ice crystals during the process. Once stored in liquid nitrogen (-196 degrees Celsius) the cellular activity is essentially brought to a halt, allowing the oocytes/embryos to remain viable indefinitely.
When patients decide to attempt a pregnancy with their cryopreserved oocytes/embryos, a reverse process of thawing will be performed whereby the cryo-protectant will be replaced by water rehydrating the cells.
Patients having surplus good quality embryos besides the embryos selected for embryo transfer. Those embryos can be vitrified in order to have extra chances, if required, of having a baby in subsequent embryo transfers without the need to undergo a new stimulation cycle.