Evolution of Fertility in Russia: A Birth Cohort Perspective

On April 23, the International Laboratory for Population and Health Research at HSE University held its regular scientific seminar. Pavel Kishenin, a Research Intern at the laboratory, presented a report titled "Evolution of Fertility in Russia by Mother’s Age and Birth Order: A Birth Cohort Lens."

Research Focus

The researcher focused on analyzing age-specific and parity-specific fertility patterns across Russian regions. The primary emphasis was placed on the transition from traditional period indicators to the "optics" of birth cohorts. This approach allows for the separation of short-term fluctuations caused by changes in the timing of births (tempo-effects) from fundamental shifts in completed fertility.

Data and Methodology

The study was based on data from five national censuses (from 1979 to 2021), which enabled the reconstruction of reproductive trajectories for Russian women starting from the 1935 birth cohort. The methodological framework relies on Bayesian hierarchical modeling (following the SSP-2 IIASA-2025 scenario specification). The model accounts for the hierarchical data structure across all 83 Russian regions, providing the capability to not only analyze the past but also generate robust probabilistic forecasts for cohorts currently in their active reproductive years.

Key Findings

The report presented regional clustering results demonstrating a gradual "standardization" of reproductive behavior in many federal subjects of the Russian Federation. However, the author also highlighted the risks of an "East Asian scenario" for several regions with delayed modernization (specifically, the national republics of the North Caucasus and Siberia). These regions may face a sharp transition to ultra-low fertility if the development of social institutions lags behind the pace of demographic change.

Discussion

The presented results sparked an active discussion featuring leading experts: Elena Churilova, Sergey Zakharov, Evgeny Andreev, Irina Troitskaya, and Dmitry Zhdanov.
Svetlana Biryukova served as the reviewer, providing a deep analysis of the work and offering several important critical remarks concerning the refinement of regional specifics and the interpretation of the contribution of different birth orders. These recommendations will assist the author in further developing the forecasting component of the research. The second reviewer was Polina Kuznetsova, a Leading Researcher at the Center for Institute of Social Analysis and Forecasting (IAES).
The seminar participants reached a consensus that the use of birth cohort indicators allows for a more accurate assessment of demographic momentum, which is critically important for the planning of family and social policy measures.