The Concentration of Reproduction in Cohorts of Women in South Korea: General Trends and Educational Differentials

Increases in childlessness and a shift of childbearing to later age are common features of countries with low fertility. The rise of childless women and diversified fertility behaviors indicate that childbearing is concentrated onto population segments. If births are unequally distributed, particularly toward disadvantaged groups, social inequality may be intensified at least with respect to social reproduction. Despite widespread interest in low fertility, concentration of reproduction remains relatively unexplored. This study explores concentration of reproduction in South Korea, one of the lowest-low fertility countries. Based on cohort analysis of Korean Census samples data, I look at concentration ratios (CRs) in cohorts of women born in 1926-70. To be specific, I investigate the relationship between change in CRs and fertility transition and how it differs across women’s educational attainment in South Korea. The results of this study suggest that as completed fertility reaches below replacement level, the relationship between CR and fertility level changes from negative to negative around replacement level of completed cohort fertility. This study contributes to finding a general relation between CR and fertility level and expand its discussion to East Asia.