I must say that it is one of a very interesting topics of population growth in the world. The fact is that Third world countries or the South East countries are growing very fast in terms of population as compare to North side counties. The reason is that people there believe that more children can give them more sources of income while the people in the developed countries usually end up with single parent family. There are a number of other reasons which are increasing population growth in countries. You can see that there is less population growth in Japan while very high in Bangladesh, India and other developing countries.
Population growth in developing countries
Population growth in developing countries