Dhaka's growing at tremendous speed. When I was in Bangladesh last month, my parents were talking about how places that were well outside the city when they were young are part of the metropolis now; there's no sign that this trend is stopping. The whole country is flat, so there are no natural boundaries to the city's growth except wide rivers.
What's the Muslim take on the birth control pill? If ever there were a place that needed some contraception, it's Bangladesh.
I don't know how widely used it is, but birth control is permissible from a religious standpoint and legal. So is early-term abortion, for that matter, although it's officially referred to by the euphemism of "menstrual regulation".