tigerbaby,
actually er not that they are outside they will die fast.. the sperms will need to go thru a long way to reach the uterus and before they reach the uterus, some weak sperms would have already died or if a person have hostile cervical mucus... all the sperms would have died......
only the strongest one will enter the fallopian tubes and wait for the eggies to come out.
during a sperm test, dh will have to produce a fresh sample on the spot... some do it at home but within 1 hr must bring back to hospital...
it does not show how long sperms can survive .. it will test how fast the sperm can swim, the shape of the sperm and the quanity of the sperm.