|MadSci Network: Medicine|
It is the consensus in medical schools that sperm can survive around 72 hours after ejaculation. In certain environments, of course, this time can be extended and shortened. IF the sperm are frozen, they can be stored live indefinitely. If they are subjected to excessive heat, above 100 degrees farenheit,they quickly die. Basically they are designed to do one thing and are well suited to it, but they are not intended for a delayed effect. In this situation 72 hours is probably longer than will ever be necessary for natural pregnancy to occur.
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