Vladimir Putin knows this and his Nashi or "Ours" group is setting up giant Woodstock-style rallies/orgies to encourage young Russian to create a new generation. Best of luck to the effort.
Meanwhile Britain is also having negative growth (note: the raw number growth rate is slightly positive; however, that includes immigration which is keeping the number afloat) yet environmentalist are calling for even more limits on families. The Economist magazine is wondering if children should be considered a public good.
Hopefully these two countries can figure out something to grow and not perish.