I think, as it stands right now, there doesn’t yet exist a moral way to proceed with all the spare embryos.
1: can’t intentionally use/kill them for science
2: can’t use in vitro fertilization-takes out the marital act
3. can’t “let them thaw” and die a natural death - this amounts to intentional killing of the embryos, in my opinion. It would be like letting a newborn infant lay on a table after birth until it starved, or died of exposure.
I think one poster had the most viable option (although it is not yet scientifically/medically possible) and that is consider that each embryo is similar to an extremely premature baby (which they are, in fact - just not naturally “born”) and work towards developing some sort of “artificial womb” like an incubator system currently used for preemies, to help the embryos develop. Don’t know if it’s possible, but hey, I think it would be a moral solution to bringing these babies to full development.
Other than this, I don’t know…