@indigomoth - It's easy to say that, but adoption can be almost as invasive and expensive as fertility treatments. And a problem with acrosome function isn't that big a deal in terms of fertility issues, after all, since they can manipulate the sperm and egg in a petri dish then implant it.
I actually think what's more of an issue is that fertility problems are actually fairly wide spread, not just in people, but also in other animals.
We should be looking for the overall cause of this decline as well as focusing on individual cures. If the decline continues we could all be in big trouble, since coupled with habitat loss it could impact on wild populations.
Of course, in a way, it's actually a good thing for human populations since those certainly don't need to increase any further.