Birthrates are falling rapidly around the world, yes, including in places you may think are populated with "low conscious" people. The reason is very prosaic: urbanization. As people get crammed into smaller areas, they naturally start to reproduce less.
It goes back to the fundamental human urge to take care of our offspring: an overcrowded city is also a highly competitive city (Tokyo, Hong Kong, New York etc illustrate this best) so people who live in that environment that don't want to bring more offspring into the world.
Even in a country like India, the population growth is almost all rural. The birth rate of city-natives in big cities has dropped well below replacement level, and cities are gaining population because of immigration and within one generation those rural-turned-city-dwellers have low birth rate.