It's not. Fertility rate for the US and the developed world is below replacement. And in the developing world, it has been dropping consistently.
> One reason why people have less children is that more of them survive.
That's a reason why women don't have 5 or 6 children, but that's not a reason why women has less than 2 on average.
Basically, some people think men should have a right to abdicate responsibility for a pregnancy at least up to a certain point.
Are there any specific plans for this that are not harmful to the child or society?