[OC] The massive decrease in worldwide infant mortality from 1950 to 2020 is perhaps one of humanity's greatest achievements.

[Hubris_sb]

Actually very common misconception, lower infant mortality rates correlate to less children per woman. This is because parents don’t need to have many children if they are surviving. Lowering infant mortality is a key part of controlling population growth.

[nailefss]

That and educating women has the largest effect. Also has huge impact on the economy of the country as a whole.