Monograph - is the first comprehensive work in Russian literature that reveals the features of population reproduction in developing countries. Based on a comprehensive socio-hygienic analysis using modern methods of sanitary and statistical research and a number of mathematical techniques, the most important indicators of the static and dynamics of the population were studied on new statistical materials; the main trends in demographic processes and patterns of their relationship and relationship with living conditions were identified, their importance for solving health problems was proven. Based on the study of numerous works of domestic and foreign authors, options for one of the most common theoretical concepts, neo-Malthusianism, were considered. In addition to generally accepted logical evidence, the authors used the results of statistical analysis in criticizing neo-Malthusianism. Analyzing the patterns and trends of demographic processes of bilateral links between socio-economic development, health and public health, including demographic indicators, the authors illustrate the possibilities of analyzing population problems from the standpoint of medical demography.