Razlike u kohortnom fertilitetu prema migracijskom obilježju: slučaj Grada Zagreba
Authors:   Ekonomski fakultet Sveučilišta u Zagrebu, Zagreb, Čipin Ivan 
Published: December 2022

The impact of migration on fertility is becoming an increasingly common research theme within the framework of population studies. Numerous demographic and geographical studies have found lower fertility in urban than in rural areas, both in developing and developed countries. Structural and contextual factors most often explain this difference. Structural factors refer to people of dissimilar socio-economic characteristics living in different areas, while contextual factors cover the current living conditions in the broadest sense. However, when explaining the urban–rural fertility differences, the selectivity of migration should also be considered, as people who (currently) have no fertility plans prefer to move to large cities. Most studies that measured fertility levels by migrant characteristics have relied on period fertility rates, while only a few have investigated cohort fertility. This study explores the cohort fertility of females by migrant status in the City of Zagreb, the largest urban centre in Croatia. Therefore, the aim is to better understand the relationship between completed fertility and migration in an urban context. Within a country, areas with the lowest fertility are often capital cities with highly educated and highly mobile populations. Although the fertility of international mi¬grants attracts more attention than internal migration, studying the association between fertility and both types of migration is especially important in a capital city with relatively high rates of inward migration. How much is known about the repro¬ductive behaviour of inward migrants in Zagreb? Are there significant differences between their fertility patterns and the patterns of native women? This paper fills this gap in the Croatian demographic literature by comparing fertility differences by migrant status across cohorts. The analysis is based on the 2011 Census data for the City of Zagreb. The Central Bureau of Statistics created a multidimensional table based on the data from this census, which includes the following variables for the female population of the City of Zagreb aged 15 or over: year of birth, number of liveborn children, highest completed education and place of birth. For analytical purposes, the data were aggre¬gated into eight five-year cohorts, with the oldest cohort born in 1930–1934 and the youngest in 1965–1969. Fertility is measured as the completed number of liveborn children per woman, which corresponds to the cohort fertility rate (CFR). The calculations are based on the standard analytical procedures used in cohort fertility analysis with census data or reproductive histories from surveys. Women are classified into four categories by migrant type: born in the City of Zagreb (native population), born in another city or another municipality in the Republic of Croatia (internal migrants), born in Bosnia and Herzegovina (external migrants – B&H), born abroad other than Bosnia and Herzegovina (external migrants – others). The 2011 census data on the number of live births are retrospective and based on the census question asking for the number of children a woman has ever had, including children who were no longer alive at the time of the census. The analysis is restricted to women born from 1930 (aged 80–81 at the time of the census) to 1969 (aged 41–42 at the time of the census), as younger women may have (more) children, while the fertility of women over 80 may be biased due to mortality and non-reporting of de¬ceased children. The analysis has shown significant differences in cohort fertility in the City of Zagreb by women’s place of birth. In all cohorts, the lowest completed fertility was achieved by women who were born in the City of Zagreb and (most likely) had no migration experience. In older cohorts, the highest fertility was recorded among women born in Bosnia and Herzegovina. In younger cohorts, fertility was highest for women born in other countries abroad. The substantial difference in completed fertility between older cohorts born in Bosnia and Herzegovina and those born in the City of Zagreb is not surprising, given that considerable differences in cohort fertility were observed between the equivalent cohorts in Croatia and Bosnia and Herzegovina. The comparison between cohort fertility rates in the City of Zagreb and Croatia shows that the cohort fertility rate in the City of Zagreb is about 0.25 (in younger co¬horts) and about 0.5 (in older cohorts) lower than in Croatia as a whole. The completed fertility of Zagreb-born women and those born elsewhere in Croatia slowly grew from older to younger cohorts (except for the youngest one). A similar trend, with some fluctuations, was observed for cohort fertility of women born abroad other than Bosnia and Herzegovina. On the other hand, completed fertility for the cohorts born in Bosnia and Herzegovina shows the opposite intercohort trend, with a notice¬able decline from the oldest to the youngest cohorts. Nevertheless, the overall cohort fertility trend is equal to that for the cohorts born in the City of Zagreb and the cohort of in-migrants from other cities/municipalities in Croatia. The share of childless women in the analysed City of Zagreb cohorts ranged from 11% to 15%, except for the youngest cohort (19%). The proportion of women who had only one child decreased from a relatively high 38% in the oldest cohort to 22– 23% in the cohorts born during the 1960s. The share of women of low parity (parities 0 and 1) decreased over time. While they represented a clear majority in the cohorts born in the 1930s, they account for below 40% in those born from 1945 to 1964. In these cohorts, in the City of Zagreb, the model of two-children families was prevalent, which is not surprising as in most post-socialist countries, having two children was a standard at the time. Women born in Bosnia and Herzegovina had lower childlessness rates than the other three categories. Women from the native cohort, especially older ones, have a rela¬tively high proportion of parity 1, while among women born in Bosnia and Herze¬govina, parity 1 is relatively low. There were no major differences in parity 2 among the analysed cohorts, with a slightly higher proportion of the two-children norm among women born in Croatia and somewhat lower in cohorts born abroad. This is expected because approximately half of the women born in the City of Zagreb in older cohorts no longer participated in reproduction after the first birth. On the other hand, women with higher parities (3 and 4+) dominate among women born in Bosnia and Herzegovina in older cohorts and among women born elsewhere abroad in the youngest cohorts. This is due to their relatively high progression to the third child (parity progression ratio 2→3 rose from 0.45 to 0.6). Interestingly, younger cohorts of women born in the City of Zagreb and the rest of Croatia are more represented in higher parities than the older cohorts. A possible explanation lies in the potentially disproportionately more significant impact of the second generation of the immigrant population whose parents were born abroad, but we should not ig¬nore numerous other economic, institutional and cultural factors of migrant fertility. In the City of Zagreb, the number and share of women with primary education has decreased, while the number and share of women with secondary and higher levels of education has increased. However, cohort fertility for all three educational groups has increased over time, with a slight decline in the youngest cohort among women with medium and high education. Probably due to the previous selectivity among the highly educated, the oldest cohort recorded a very low rate of completed fertility (about 1.1). The analysis has shown that the reproductive behaviour of in-migrants in the City of Zagreb differs from that of the native female population, depending on the place of origin. The difference between internal migrant women is minor – on average less than 0.1 children, with a convergence in the cohort fertility of younger cohorts. At the same time, the cohort fertility of women born abroad is significantly higher than of women born in Zagreb, on average by one child in older cohorts of women born in Bosnia and Herzegovina and by 0.5 children in younger cohorts born in other countries. Moving to the largest city in the country is apparently associated with lower fertility due to adaptation to high competition in the sphere of economic life on the one hand, and low urban reproductive norms on the other. The role of selective migration and the fact that individuals and couples who do not plan to have children disproportionately move to the largest urban centres should not be ignored either.