It means “a society without children.” Supposedly it means economic disaster.

A former prime minister who is in charge of the governing party’s committee on population famously told women to stay at home and breed.

Fightin’ words, dude. Your economy would be better served by more working-age adults in the workplace, not by sending half of them home to make babies and letting the other half stay out til all hours “working” (actually, drinking with their cow-orkers).