Pardon the slightly off-topic comment but statements like these are misleading. It's economic growth in the true sense of having X and growing it into X+Y. At best, it's more like economic expansion.
The truth is, it's population growth. Instead of the abstraction why not simply report the population growth knowing that eventually the economy will expand to that population?
There's a difference between "the economy grew" and "more births." Maybe it's because politicians can't really take credit for the latter?