For the surrogacies, they usually fertilize several embryos then implant up to 5 in the surrogate mother, in the hopes that at least one of them takes. If more than one takes, then they have agreements worked out in advance for stuff like that. They can either "reduce," which is a nice word for aborting all but one of the embryos or the parents could decide to take multiple children.
However, if the surrogate mother is not willing to reduce, then they will implant one embryo at a time and keep repeating the procedure until one of them takes. This is obviously not preferable for the parents wanting the child, since it's much more expensive and could take much longer for them.
As for what happens to those embryos in the afterlife, only GOD knows. I will say that nothing dies on this planet without GOD's permission, so He's got everything completely under control.
Why does GOD allow abortions to continue if the practice is so horrible? Well GOD allowed child sacrifices in the Old Testament days to continue and that was a much, much more horrific practice than abortion. GOD put up with it for as long as He was willing to and then simply wiped out those civilizations to the point where historians are having trouble finding evidence that the civilizations even existed in the first place.
I think that's the future that we can look forward to here in America if we continue on the path we are going right now.