Completed Childlessness and Unrealized Fertility Ideals in Three Low-Fertility Southern Cone Settings

Fertility decline in Latin America has entered a stage in which the key issue is not only how many children individuals have, but whether they achieve their desired family size. This study examines unrealized fertility—defined as having fewer children than one considers ideal—through a parity-specific lens in three low-fertility Southern Cone settings: Uruguay, Montevideo, and Buenos Aires. Using data from the second round of the Generations and Gender Survey (GGS-II), we analyze men and women aged 40 and older who have completed their reproductive lives. Logistic regression models assess how completed parity—childlessness, one child, two children, and three or more children—is associated with the likelihood of underachieving ideal family size, both in pooled samples and separately by gender. The results show that unrealized fertility is strongly concentrated at the lowest parity levels. Childless individuals exhibit the highest likelihood of underachieving their ideal family size across all settings, indicating that unrealized fertility is closely tied to the failure to transition into parenthood. In contrast, individuals with two children display dramatically lower odds of underachievement, consistent with the persistence of a two-child norm. Those with three or more children rarely report shortfalls, suggesting that unrealized fertility is primarily a phenomenon of low parities. While this pattern holds for both women and men, some variation emerges across settings, particularly in the distinction between childlessness and one-child families. These findings suggest that low fertility in the Southern Cone reflects not only changing preferences but also barriers to achieving desired fertility, especially at the transition to first birth.