Mr. FrumGuy:
I assume you were asking your question innocently, but I found it extremely insensitive. Some commenters were on the mark in noting that we can pick and choose our tzedokos to some degree. However, your question inquired whether this was a tzedokoh or not, and that is offensive, even if you denote that you don’t intend to offend. If you understood anything about the infertile couple, their situation is one in which they lose the will to live, with every moment of every day being painful. I won’t expound on that; check out the Bonei Olam website. If tzedokoh is “Dai machsoro asher yechesar lo”, then this tzedokoh is right up there among the highest.
However, there is another matter involved here. We earn Hashem’s gifts on the merit of what we do for others, midoh kineged midoh. If we are gracious in helping others have children, we earn the merit of nachas from ours. If we get choosy about giving to others, then Hashem can treat us midoh kineged midoh and check us out before granting us anything. I am not making up this concept – it is well referenced in many seforim.