What is bringing down birth rates in Thailand, in Costa Rica, in Malaysia, is the empowerment and enrichment of poor women. Education, health care, decent jobs, family planning programmes, wherever these are generously available, family sizes come down.
By and large, people in the developing world have big families because they want them, not because they are unable to figure out how to have fewer children. An Indian who sees his children as capital because at the age of nine they can be sent to work in a carpet factory, is not going to have a keen interest in family planning. If this hypothetical impoverished Indian father does not today desperately need the money that his children can earn, he will need it in his dotage. Offspring are the social security of traditional cultures everywhere, a form of savings that few can afford to forgo. Pills and propaganda will be ineffective if having many children continues to be the rational choice of parents.