“…The exploration, however, merits further investigation to better understand the nature and dynamics of demographic variations in China, where extremely rapid changes are underway in economic, social, and demographic realms. In the field of fertility research, centreing on the framework of innovation/diffusion or adaptation (Carlsson, 1966), many studies are directed to examine historical fertility decline (Basten et al, 2011;Bras, 2014;Goldstein & Klüsener, 2014;Klüsener et al, 2016). This might be related to the fact that these theories originate from the explanation to historical fertility decline in European societies.…”