>>8
Nature doesn't have an adjustment mechanism, this implies it was engineered which is a philosophical matter and not a scientific one. If god (or allah, buddha, new age bullshit or whatever) exists then I am pretty sure they have created this universe for the express purpose of us being rational and using science to solve problems, or they would have not engineered it in such a manner as to suggest this, so for the sake of argument we should be investigating it's nature rather than it's creator.
That's another problem, since the religious folks are the ones that are continually repopulating at an increasing rate. How many of them would be fundamentalists and reject rationalism and science, I have no idea, but to be sure it's going to be a rather large chunk of that group.
other factors include the inclination of poor couples to have large families, prohibitions and poor access to contraception aswell as factors that reduce the ability to supply the population such as drought, war or oppressive regimes using starvation to pacify a population.
I'm not sure how much it would cost to produce, but there's environmental factors involved when it comes to disposal of birth control and whatnot. There really doesn't seem to be a way around it. You'll get called a monster if you suggest to cease all aid to third-world countries, which I would not disagree, but this population boom is vastly unsustainable in the long-term.
It sounds like now would be a good time to seriously consider colonizing other celestial bodies in space, and subsidizing national space programs have vastly increased technological advances in the past. There also needs to be a hold on privatization of certain industries as well since that has killed R&D big time.