Comment 8 by Net :

actually, in this day and age of over-population, and all that that means, i'm not sure why people have children. i'd have thought that if they wanted a family, they'd be doing everybody a favour by adopting.

Then you don't understand basic biology. Why does any creature reproduce? It's the way we have evolved. it's why there are so many of us. People have the same urge to reproduce as ants or fruit flies. Just because we have a better understanding of the impact of more people in the world is not going to make most people who want children not have them and adopt someone else's instead. If someone wants a child and is capable of reproducing and decides to adopt instead because of overpopulation, it would indeed be an incredibly selfless thing to do but it would go against thier very nature to do so. I don't see that many people thinking like this.