Malthusianism is, fundamentally, a failure of economic understanding
fightaging.org
fightaging.org
Of course, (almost) no one believes this will actually happen. Instead, it will be either contraception or war/famine/disease that will end the growth. There are no other possibilities, so let's hope it is the first of the two. :)
Here's a crazy idea: The amount of enjoyment parents get from raising a child has stayed about the same for thousands of years, and it doesn't look like it will increase any time soon. The amount of enjoyment provided by video games, movies, music, and other media is increasing. Not only are artists and designers improving their craft, but new, more immersive technologies are being invented for entertainment. Nobody died from playing Pong. The same is not true for modern games such as World of Warcraft.
So maybe video games will become addictive enough to save us all from a Malthusian catastrophe.