Almost all the developed countries in the world are currently experiencing demographic transition at varying pace and levels. It is generally accepted that the pace of demographic transition is closely associated with the levels of socio-economic development. India is in the midst of demographic transition to lower fertility and mortality, this shows that the pace of social and economic development is flourishing in India with the global economic development. For the present study Tamil Nadu and Uttar Pradesh have been selected, which gives two different pictures of fertility rates in Southern and Northern states of India. The pace of fertility decline has been faster in southern and coastal regions, and at a slow pace in backward northern states. The Study shows that Fertility rates have been higher among the most vulnerable and deprived sections of the society like Illiterate women, women belong to scheduled caste, scheduled tribe and women residing in rural areas.