I think with the rising affluence in China and the associated cost of bringing up children....basic care, child care (working parents), education etc etc etc it may just be that the desire for many children will be overtaken by these new realities. As has happened in the West, rising affluence has ALWAYS tended to depress the birthrate, not the opposite as may be assumed ??
We will see.
Ming is convinced that 2 child families will be the max, except for the rural peasants who need large, cheap labour forces that are cheap to make if you dont have TV, movies, theatre or other distractions