Discourage

If I were able to I would actively discourage people from having more than say one or two children.
I would penalize couples who had more than 2 children - make their tax rate higher, remove child endowment.
As for single mothers - I would actively remove all support from these people - in fact I would fine them.
We need to face facts and realize there is simply too many people in this world.
Its not good enough to expect people in 3rd world countries to toe the line and stop reproducing - we must all actively reduce our populations.
And stuff the economists and business people who all say we need population to thrive.
Most of us in the western world live beyond our means and this cannot continue - its time to face facts.
Its like the WWF, it has been said that if the WWF spent their entire budget on condoms  the result would be more beneficial to the worlds animal life! Less people = happier & healthier animals.