Quote:
Originally Posted by Gordon Booth
Thanks, DP, sort of rules out bringing you back to life, full of antifreeze, doesn't it?
Still, if they could do it you'd make a good Antarctic explorer, wouldn't you? No need for all those warm clothes.
Doesn't explain how they freeze sperm and eggs though. I'm sure they're not full of antifreeze, if they are we're pushing evolution hard!
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Gordon, it does seem that the same methods are used for sperm and doesn't seem to stop the little blighters swimming.
Semen cryopreservation - Wikipedia, the free encyclopedia
As for eggs, they are not usually frozen. It is embryos that are frozen, after fertilisation. However, freezzing of eggs is at an experimental stage. The following information is taken from the Macmillan charity website regarding loss of fertility after cancer treatment.
Freezing embryos
This is the most effective way of preserving fertility. After your eggs have been collected, they’re placed in a test tube with your partner’s or a donor’s sperm to see if they fertilise. This is called
in vitro fertilisation (IVF). The eggs that are fertilised grow into tiny embryos, which are frozen and then stored.
When you’re ready to try and get pregnant after treatment, the embryos are thawed and placed in the womb to see if they implant. Usually, no more than one or two are placed in at a time. Although pregnancy rates using frozen embryos are lower than when embryos are implanted immediately, lots of babies have been born using this technique.
Freezing eggs
If you don’t have a partner you may want to freeze your eggs and have them fertilised later when you’ve met someone. This is still experimental but techniques are improving. It’s available privately and on the NHS in some units. Eggs are collected as usual (as described above) and are frozen and stored. When you’re ready to try to get pregnant, the eggs are thawed and fertilised by injecting a single sperm directly into an egg. This is called
intra-cytoplasmic sperm injection (ICSI).
If any eggs are successfully fertilised, the resulting embryos are placed in the womb to see if a pregnancy develops.
Freezing eggs and ICSI is much less likely to result in a pregnancy than embryo storage, but success rates are improving.