Approaching the limit:: Long-term trends in late and very late fertility

This article describes trends in the limits to late childbearing, their determinants, and their potential implications from an empirical long-term perspective. Although in contemporary low-fertility populations the levels of late fertility remain far below those observed in natural fertility populations, fertility in Europe and the United States at ages 40+ and 45+ has increased substantially in recent years. This trend has received considerable attention in the media, especially in combination with the emergence of new assisted reproductive technologies and levels of general fertility. Nevertheless, physiological studies agree that age limits to giving birth have not shifted to later ages. Analysis of high-quality long-term data from Sweden documents an increase in the absolute and relative number of births at ages 40+ and 45+, together with an increase in first-birth occurrence-exposure rates at ages close to 40 years.