In this context of crisis, poverty and social unrest no attention to the issue of population or demographic changes taking place, let alone take into account developments that will in the future, and their impact is provided as a source of social demands in health. It is clear to everyone that major changes are made by the process of urbanization with the excessive growth of cities based on the marginal urban areas, changes in population structure with a marked increase in teenage poblaci6n a high rate total fertility, and one of the most the tas rates of infant mortality and Maternal America, particularly affecting the most vulnerable social groups in rural and marginal urban areas and in the case of Maternal mortality is predominantly preventable causes. It is also clear and obvious how easily the most disadvantaged population groups in which the major health problems are concentrated ...