Ryazantsev S.V., Rostovskaya T.K., Zolotareva O.A. Characteristics of the reproductive behavior of the population in Iran and Russia during the Pandemic period COVID-19. Gigiena i Sanitariya (Hygiene and Sanitation, Russian journal). 2021; 100 (10) . https: ... Ryazantsev S.V., Rostovskaya T.K., Zolotareva O.A. Characteristics of the reproductive behavior of the population in Iran and Russia during the Pandemic period COVID-19. Gigiena i Sanitariya (Hygiene and Sanitation, Russian journal). 2021; 100 (10) . https://doi.org/10.47470/0016-9900-2021-100-10- (In Russ.)ISSN 2412-0650DOI 10.47470/0016-9900-2021-100-10-1163-1170РИНЦ: https://www.elibrary.ru/item.asp?id=47130590Posted on site: 27.11.21 AbstractIntroduction. The urgent issue of the challenges of the COVID-19 pandemic, which negatively affected the demographic development of the world’s countries, is the search for new effective mechanisms for the development of demographic potential, which is not possible without appropriate justification monitoring data. The aim of the study is to analyze trends in demographic processes and assess the reproductive behavior of the population of Russia and Iran, as well as develop recommendations in the field of monitoring demographic processes, taking into account the need to study their changes as a result of the spread of COVID-19, which seems significant for determining effective directions and measures of demographic policy in terms of increasing the birth rate in Russia and Iran in the post-pandemic period. Materials and methods. The article is based on the data of the official national statistics of the countries (the Federal State Statistics Service of the Russian Federation and the Statistical Center of the Islamic Republic of Iran), the international database of the UN Population Division, and sociological information. The general research period is determined by the boundaries from 2000 to 2019. To assess the determination of reproductive behaviour in Russia and Iran, general statistical methods of data analysis were used (for example, indicators of structure, dynamics, implementation of the plan), unique methods of demographic statistics (construction of age and sex pyramids of the population, total fertility rate, and others), methods of sociological research (results are presented as All-Russian sociological research “Demographic well-being of Russians”, conducted with the participation of the authors in 2019-2020 on the territory of 10 constituent entities of Russia). Results. An assessment of fertility trends in Russia and Iran is given, general and specific traits of the character and mechanisms of reproductive behaviour are identified. The substantiation of the improvement of directions and measures of demographic policy is given, taking into account the assessment of its effectiveness. In Russia, it was aimed at increasing the birth rate. In Iran, on the contrary, at decreasing it. In both countries, the policy was very effective - in Russia in 2007-2016. the birth rate for second and subsequent births increased significantly in Iran in the late 1980s-1990s. The decline in fertility was one of the largest in the world. If in Iran the birth rate is now close to the level of simple reproduction of the population (in 2017, the total fertility rate was 2.12), then in Russia, especially after the decline since 2017. In this case, it is far from this level. Conclusion. The article substantiates the need to improve scientific monitoring of the demographic consequences of the COVID-19 pandemic.