Freezing of sperm and eggs is widely used.
I propose surgical removal and cryogenic freezing of the testes and ovaries, for reattachment when they are desired for reproduction. Aside from the contraceptive benefits, this procedure would protect the germ cells from aging and radiation, reducing the risk of cancer and birth defects. For men, there is the additional benefit of making a very sensitive area less sensitive.
The science to do this is not quite ready, but it's close (ie rat organs that are frozen can sometimes be successfully thawed).-- sninctown, Apr 25 2009 Yes, I'd like to keep mine where they are. There might be an argument for removing and preserving ovaries (when the technology gets there), particularly if a woman had to undergo aggressive chemo- or radio-therapy. I believe that eggs are sometimes harvested and stored for this very reason.-- MaxwellBuchanan, Apr 25 2009 despite the obvious temptation of having surgical steel replacement balls that CLANG while you walk, I'm gonna have to say no.-- FlyingToaster, Apr 26 2009 Baked.-- loonquawl, Apr 27 2009 random, halfbakery