“China warns parents against Hong Kong ‘birth tours’ ”, H-S, 8/2 (also at The Age). Here is evidence that some people will go to great lengths to avoid birthrate control restrictions – in this case, Chinese women going to Hong Kong to have more children. It shows that some can be irrational when it comes to reproduction and they therefore can’t be trusted to do the right thing. The punishments are monetary fines, but in a future dystopia, or fictional one, these punishments could be a lot harsher (I’ll leave those to the imagination). If you look under my fiction tag you can see previous entries with examples of these dystopias.