Italy's fertility rate = 1.37. It would have to shoot up by over 50% just to hit Zero Population Growth.
And nothing can stop other nations with young, expanding populations from flowing into the vacuum. It would be comparable to trying to brake the revolution of the moon and stop the tides.
Have bambini, or Addio, Italia.
Most countries have far too many people to begin with and could do much better with fewer. For damn sure the US. Population was 140 million when I was born now who knows..somewhere north of 300 million.