Delayed childbearing has been found detrimental to children's health. While post-transitional China is observing a substantial increase of childbearing postponement, this study aims to investigate health impact of this trend on the next generation. Using data from the 2010-2020 China Family Panel Studies（CFPS）, this study examines the multidimensional health differences related to both maternal and paternal ages in post-transitional China. The results show that delayed childbearing contributes negatively to children's birth weight, their physical development in childhood, and general health in adolescence. These health impacts operate partly through congenital factors, as manifested in the greater risk of low birth weight, and partly via the related family environments and resources. These findings highlight the need to incorporate health considerations into decisions about childbearing, both for health promotion and for sustained population development. 

China has witnessed great volumes of migrant workers returning hometown in the past decade. Meanwhile, an increasing number of cities, especially the major migrant-receiving cities, started to encounter severe labor shortage. This study investigates whether the recent returning flows have selected migrants of higher human capital and thus contributed to a significant loss of human capital in those traditional hosting areas. The results suggest that migrants with higher education have been less likely to return hometown, and they remain so even today. Nevertheless, male migrants having agricultural working skills are increasingly more likely to return hometown recently. Yet, the impact of health condition on returning decision is rather complex. There have always been migrants with deteriorated health condition returning home. This study concludes that migrant workers make their decision to return or not return rationally according to their human capital and comparative advantage. To date, the returning flows of migrants have not resulted in a significant loss of human capital, albeit it might have contributed significantly to labor shortage, in many cities.

Drawing on data from the 2008 Chinese Internal Migration and Health Survey,we compare various health indicators among rural residents who never migrated,return migrants,current rural-to-urban migrants,and urban residents.Two health selective mechanisms,the healthy migrant hypothesis and the salmon bias hypothesis,are empirically tested.Results provide empirical support to both these hypotheses.After controlling for individual’s age,sex,socioeconomic status and major health-related behaviors,rural-to-urban migrants are better off than rural residents who never migrated regarding their self-rated general health,chronic medical conditions,self-perceived physical discomforts and lung capacity.Current rural-to-urban migrants are also less likely to have chronic diseases or to report physical discomforts than return migrants.Except for self-reported chronic conditions and abnormally high heart rate,there is no significant difference in health status between rural-to-urban migrants and urban residents.