Annette Baudisch , Interdisciplinary Centre on Population Dynamics (CPop)
Andrés Castro, Max Planck Institute for Demographic Research
José Manuel Aburto, CPop, University of Southern Denmark
Quantum and tempo are central dimensions of fertility studies. Less attention has been devoted to the shape of fertility. Although the shape of a fertility curve over age might, at first sight, be over determined by quantum and tempo, two aspects make it a crucial dimension of human reproduction. First, shape summarizes the overall distribution of births’ timing providing a holistic indicator of how reproduction is spread over the life course. Second, the shape of fertility can be defined with respect to baseline patterns of various forms. This latter feature gives important flexibility capturing diverse patterns and opens the door for comparisons with biological baselines. Biodemographic research motivated the shape concept as part of the pace shape framework tailored to compare aging patterns of mortality across species. Comparing fertility patterns across human populations with the same methodology requires to deeply acknowledge that you are only born once. One can imagine a ‘population’ of unborn babies waiting along a ‘survival curve’ for the event of being born to a mother of uncertain age. With this radical shift in perspective, here we offer a new macro level perspective to study the development of human fertility patterns, which accounts for births of any parity. It also opens the floor to transfer other mortality concepts into the world of fertility applications.