How and why are embryos frozen?
Human embryos can be stored very successfully by being frozen and stored in liquid nitrogen. An estimated 15-20,000 babies have been born as a result of the freezing technology. Drug-induced stimulation of the ovaries, resulting in super ovulation, leads to an excess of embryos being created that can’t all be transferred to the uterus at the same time. The good quality excess embryos can therefore be stored by freezing for transfer to the uterus at a later date. It should be noted that poor quality embryos do not withstand the freezing process that well, and hence are not generally frozen. This technique allows couples to have more attempts at IVF without the need for the woman to have to undergo another stimulatory cycle of IVF for egg collection.The success rates following transfer of frozen thaw embryos is in the region of 10-15 % – not as good as the fresh cycle success rates. In some countries freezing of embryos is restricted or banned (e.g. Germany and Switzerland will only allo
Human embryos can be stored very successfully by being frozen and stored in liquid nitrogen. An estimated 15-20,000 babies have been born as a result of the freezing technology. Drug-induced stimulation of the ovaries, resulting in super ovulation, leads to an excess of embryos being created that can’t all be transferred to the uterus at the same time. The good quality excess embryos can therefore be stored by freezing for transfer to the uterus at a later date. It should be noted that poor quality embryos do not withstand the freezing process that well, and hence are not generally frozen. This technique allows couples to have more attempts at IVF without the need for the woman to have to undergo another stimulatory cycle of IVF for egg collection. The success rates following transfer of frozen thaw embryos is in the region of 10-15 % – not as good as the fresh cycle success rates. In some countries freezing of embryos is restricted or banned (e.g. Germany and Switzerland will only all
