While Indian policy makers attack the population growth problem using variety of incentives, it looks like the economic incentive trumps all others. In a recently published paper in the Quarterly Journal of Economics, Robert Jensen finds that increased awareness of prospects of gainful employment made the women facing them to be less likely to marry and have kids than those who were not aware of such opportunities. Those married were also more likely to limit the number of kids in order to pursue a steady career.
The increased economic opportunities increased the opportunity cost of getting married and having kids leading to a substitution away from them. A good example of rational behavior from rural India. You can find the paper here.
Robert Jensen, Do Labor Market Opportunities Affect Young Women’s Work and Family Decisions? Experimental Evidence from India The Quarterly Journal of Economics (2012) 127(2): 753-792