In the artical,the connotation ofthe origin of congenital constitution had been discussed through the embryo stage of the vitality.It was considered the zygote’s forming and growth depends on kidney essence quality,and the prosperity and decline of kidney-qi plays an important role in maintaining and keeping the normal embryo in its position,meanwhile discriminating and eliminating the abnormal embryo.It is an instinct of survival of the fittest the female parents by discriminating and eliminating its abnormal embryo,which is formed in the long period of evolution and has the hereditary feature.Therefore,not all of the abortions belong to morbid states,sometimes are because of the female parent eliminating her unnormal embryos to guarantee the descendant’s quality.