Moving to another city or region usually occurs when one is at the peak of marital and reproductive activity. According to the study’s authors, for those Russians who relocate, the first incident of migration to another city or region occurs before the age of 30 in 90% of cases. Therefore, it would be logical to expect mobile citizens to contribute substantially to the birth rates at their destination. The article 'The Geography of Fertility in Russia', published in the HSE's Demoscope Weekly, discusses the impact of migration on the natural population growth of the country.
The impact of internal migration on fertility is beneficial for most destination regions, according to Biryukova and Tyndik. The average total number of births per woman (calculated as the number of births a woman has given before the end of her reproductive 'career' at age 40 or so) would have been lower across Russian regions if most women of childbearing age had stayed in their home communities.
Having studied reproductive trends based on Russian census microdata, Biryukova and Tyndik found the lowest fertility rates in women who have never relocated. In contrast, moving to another city or region, despite the inevitable stress and adaptation difficulties, usually resulted in better living standards and thus indirectly supported fertility.
The researchers also examined the relationship between migration patterns and fertility and found that the distance of migration was particularly important.
Women who relocated within the same federal district (a group of neighbouring regions) showed higher total fertility than those who stayed in their home community. The difference in birth rates between women who moved within a federal district and those who never relocated stood at 0.2 (1.57 vs. 1.37 births per woman) in the Central Federal District and was even higher at 0.3 to 0.31 in the Northwestern and Volga Districts. Countrywide, the difference in reproductive performance between women who did and did not relocate stood at 0.26 (1.79 vs 1.53 births per woman).
As to women who migrated beyond their federal district, their total fertility was found to stand midway between the above groups. The study's authors suggest that relatively lower fertility may be associated with adaptation problems. In Russia, long-distance migration usually means moving to Moscow or St. Petersburg, where most newcomers need to work hard to find and keep a job, and decent housing is less affordable than elsewhere – factors that affect people's reproductive behavior.
The challenge of adaptation is somewhat less daunting for those who migrate to a neighbouring region, an increasingly common situation in the past decade.
According to Biryukova and Tyndik, "Since the purpose of relocation is to seek better living conditions, one can assume that upon moving to a neighbouring region, people find themselves in a better position for starting a family." The theory that internal migration can help solve matrimonial problems is also confirmed by earlier data from sample surveys; see S. V. Zakharov, S. V. Surkov, 2009. Migration and Fertility in Russia.)
Moscow, a city that has traditionally attracted an impressive flow of migrants, can serve as an illustration of newcomers' potential contribution to birthrates. In 2000, the Russian capital's official population stood at 10 million, increasing to 12 million in 2013. Immigrants make the capital's population younger and compensate for its natural decline estimated at 350,000 deaths over the said period.
Newcomers’ contribution to birthrates is not limited to resident Muscovites; according to official birth records, just over 70% of new mothers have permanent residence in Moscow, while immigrants account for about a quarter of all births, e.g. some 35,000 births in 2013 in Moscow, according to the study's authors.
Recent arrivals to Moscow typically give birth to more children. Graph shows a distribution of women living in Moscow by number of births and by generation; native residents are indicated by coloured blocks and newer Muscovites by lines.
It follows from Graph that since the mid-1960s, there have been fewer childless women among recent Muscovites, and this gap has been growing over time.
Similarly, fewer women with just one child have been registered among recent Muscovites – due both to a larger number of families with two children and a fairly high, although declining since the 1970s, proportion of families with three or more children among newcomers.
Today, the Russian capital is home to some 800,000 women born between 1970 and 1979, of whom a little over 500,000 are native Muscovites, while the majority of recent Moscovites are migrants from elswhere in Russia. According to the most recent census, women in Moscow had a total of 950,000 children (about one million, if infants are counted) over the period covered; of them, mothers of some 600,000 children and infants were native Muscovites, while 400,000 children and infants were born to migrants who were not necessarily residents of Moscow. Currently, according to Biryukova and Tyndik, about 100,000 children born in Moscow to migrants from other parts of Russia live outside the capital, while 300,000 children live in Moscow.
Biryukova and Tyndik expect the proportions of children born to native and recent Muscovites to stay the same among younger generations of women. The so-called Greater Moscow – the area of booming housing construction within the city's recently expanded boundaries – is likely to have a higher proportion of younger residents. In addition to this, newcomers tend to have higher reproductive expectations than born Muscovites and would like to have at least two or three children, according to surveys.
However, on average, new Muscovites have just a slightly higher total fertility than native residents of Moscow, i.e. 1.4 vs. 1.3 children per woman – both numbers refer to women born in the 1960s who have finished their childbearing careers.
Migration flows in Russia tend to contribute to regional demographic imbalances.
While certain regions experience depopulation and rapid aging, aggravated by an outflow of young people, some others, such as Moscow and St. Petersburg, Tyumen, Novosibirsk and the country's northwestern part, attract young people and report high birthrates. Such demographic ups and downs pose specific challenges for services such as assistance for the elderly and mother and child health infrastructure, the authors conclude.