Social distances decrease of body height and the maturation rate of Polish girls in urban and rural population in the period 1967–2009

Abstract

The aim of the study is to present social distances in biological development of youth in the period of changes in economic and political situation in Poland.
 Material and methods: 1. Nationwide study of children and adolescents aged 7.5 to 19.5 years started in 1979 and repeated every decade till 2009, 2. Survey conducted in the region of eastern Poland in 1987 and 2007, 3. Study of rural girls repeated four times between 1967 and 2001. The differences in body height and age at menarche between the inhabitants of towns and rural areas, as well as the differences between rural girls determined by diversified source of income for the family, will be presented. The age at menarche (AM) in each study was calculated using probit method. A monotonic decrease in body height differences between the inhabitants of towns, and girls living in rural areas was observed. On the basis of nationwide studies arithmetic means of the differences in terms of age were 1.9 cm in 1979 and 0.82 in 2009. At the same time, differences in the AM among girls in compared agglomerations decreased from 0.36 to 0.26, respectively. In eastern region of Poland the difference in body height between the residents of towns and villages in 1987 was 1.76 cm, and in 2007, only 0.38 cm; the difference of AM decreased from 0.41 to 0.14 years.
 The research conducted on inhabitants of rural areas has shown the earliest maturation and slightly greater body height for girls from landless families and the latest maturation and the smallest body height for the daughters of farmers. The differences in AM between the two groups decreased from 0.53 years in 1967 to 0.15 in 2001. The political transformation (1989) unequally influenced people on different levels of urbanization, different socio-professional groups and residents of various regions of the country, but was reflected in the results of anthropological research.
 The largest social advancement measured in terms of acceleration of maturation in the period covered by the research was characteristic for rural girls, especially the daughters of farmers.