From what I understand, the Catholic church is against any kind of birth control except the condom. China has been implementing almost all kinds of birth control that includes abortion in order to facilitate their policy on population control. One demographer said that if China did not implement population control some 20 years ago, that country would be very crowded now. India is now the densest country in terms of population and land area.
My question is this - what would happen if birth control will not be practiced, just to let people multiply according to the Bible. Is it hard to imagine that the material resources are finite so the population cannot be unlimited?