We're going to see more of the same fertility trend: developed countries reproduce less, and undeveloped countries keep producing (until they become more developed), thus picking up the gap, but overall, slowing the increase until it caps somewhere fairly "reasonable."
My problem with all this is the people who "should have not children" are typically the people having children (this is not an ethical comment--it's a comment on the thought processes that lead to or are absent in having children), and the gene pool is getting polluted. Fortunately, most significant genetic changes don't occur in 50 years, so it's probably a minor effect.
Addendum
added important and missing "not" to "should have children"