he number of men is roughly equal to the number of women in the most vital age group (20-39 years) of Serbia’s pop-
ulation due to combination of factors: sex ratio at birth, age pattern of mortality, and age pattern of international migra-
tion. However, continuous “village to town” migration during the last five decades produced disturbed sex composition
of the group at settlement level of the country. Generally, regions having more men than women aged 20-39 are poor,
agrarian, mountain and mainly border while areas populated by more women than men of the age are predominantly ur-
ban. As a result, implementation of three substantial national strategies in view of sustainable population development
(the pronatalist, the poverty reduction and the strategy on ageing) is constrained by the “frozen” reproductive potential
which is of no effective use on account of its spatial factionalism. The analysis of indicators of disturbed sex composi-
tion at lower spatial levels pointed to profound economic and social factors (analyzed through poverty indicators) as a
driving force of internal migration in a typical positive feedback loop “population-poverty”. The analysis is based on
the 2007 Living Standards Measurement Study conducted by World Bank and the 2002 Census of Population in Serbia.
Resulting polarized agrarian zones of young men surplus and urban “islands” of young women surplus reinforce
processes of demographic ageing and poverty despite the goals of policy makers. The need to overcoming the problem
of territory obstacles as a prerequisite for implementing the national strategies is emphasized through the stochastic
population projection