It's projected to level out sometime around mid century and then start declining. And that's because birth rates decrease to a below replacement level everywhere women are granted the freedom to control their reproduction, which is a global trend.
True but both genetic and mimetic evolution are pushing us to going back to having lots of children in the modern environment. Agreeableness in particular of the Big Five correlates with having kids and there are a lot of religion out there telling their followers not to use birth control. It might be that our current non-Malthusian era of history is going to be an aberration.
