Traditionally, female years of education, child mortality, and GDP per capita (in order of importance) explain 85% of fertility, and the residual is not biased in either direction.
source: Lant Pritchett, long-time development economist.
Edit: I don't think anyone outside the Taliban seriously wants to reverse the trends in any of those 3 factors.
Robin Hanson on the first, incentivized with the ability to sell shares in your child.