The exponential growth of population is already becoming a huge problem for humanity.  More people create more pollution, more demands on agriculture, more need of land for living (particularly for US middle class people who dream of owning a big house in the suburbs with 2 cars, enough road to get them in and out, schools close by and so on).  And a peculiar reality in the US and many third world countries is that for those people who have achieved a fairly respectable life, they tend to have a generally smaller number of children than those who are not able to afford it.  Family life in China is a scary prospect, but they have come up against the reality of the limits of their ability to support so many people.  I am not advocating the solution that China has come up with, but we as a whole need to rethink our code of behavior and welfare systems to deal with the current shortcomings in that code.

There are many issues that come to bear.  There is the question of whether everyone has the right to procreate - do we have the right to tell others with, for example, genetic defects that they may not have more than 1 or 2 children, if any?  What about the people who have not been blessed with talent or beauty?  Do we say it's OK for them to have as many kids as they want if it makes them feel more fulfilled?  And as our knowledge of the human genome approaches completion, do we reconsider how we are going to view genetic engineering?  What about the "men" who are proud of all the children they have fathered when they are not even acting as a father for those children and they do not have anyone else filling the role?  It is not just an issue of money.

The evolutionary reality that has been ingrained in us is that we enjoy procreation on many levels.  It is up to us to work out what we want our world to be and how to get there in light of this fact.