Technique:
Stimulation of ovaries for IVF or ICSI often leads to excess embryos being created which cannot be transferred in the same treatment cycle. These excess good embryos can be stored by cryopreservation (freezing) for possible transfer at a later date. Selection of the embryos to be frozen is at the discretion of the embryologists as they are able to selection good quality embryos that most likely can survive the rigorous freeze / thaw process. The frozen embryos are stored in liquid nitrogen at - 196ºC. At this temperature, there has been no evidence of deterioration over time

The Benefits of Embryo Cryopreservation (Freezing):
Without the option of embryo cryopreservation (freezing), spare embryos can either be transferred, donated to other couples, used for research or discarded. However, if multiple embryos are transferred, there is an increased risk of a multiple pregnancy because the greater the number of embryos transferred, the greater the risk of multiple pregnancy. Multiple pregnancy carries great risks for the mother and the fetuses.

Embryo cryopreservation (freezing) provides an alternative to discarding these spare embryos. It also provides an alternative to the transfer of multiple embryos.

Patients in an IVF program are usually given hormonal injections to produce more eggs. However these injections may have harmful consequences such as Ovarian Hyperstimulation Syndrome (OHSS). Transferring embryos in a fresh cycle will bring potential life threatening danger to patient with multiple follicles who already has an onset or at a great risk of developing severe OHSS before egg pick-up.

Embryo cryopreservation (freezing) can greatly reduce the risk and severity of OHSS as embryos are frozen in a stimulated cycle and only to be thawed and transferred during a natural menstrual cycle where no medications are given. In fact, the chance of pregnancy may be enhanced with natural menstrual cycle as embryos are transferred into a relatively more natural uterine environment.

IVF program is stressful and costly!!

Embryo freezing could help to reduce the inconvenience, discomfort and cost of IVF by reducing the need of hormonal injections which is very costly as well as the need to go through egg pick-up procedure again. Usually no medications and operative procedures are required for the transfer of thawed embryos.

SPERM CRYOPRESERVATION (FREEZING)

Technique:
Sperm cryopreservation (freezing) involves the whole semen sample to be diluted with an appropriate volume of cryoprotectant. Once cryoprotectant is added, the sample will go through a series of cooling process before it is stored in liquid nitrogen at - 196ºC. At this temperature, there has been no evidence of deterioration over time.

The Benefits of Sperm cryopreservation (Freezing):
There are many situations that may interfere with a man’s future fertility. Some are planned, some are accidental and others are due to complications of illness or their treatment. Examples are:

	Chemotherapy or radiation therapy
	Vasectomy
	Occupations with high risk of injury
	Illnesses that may cause erectile dysfunction
	Spinal cord disease or injury

Many men decide to freeze extra sperm as a safeguard against unforeseen future circumstances.