The ancient people considered the blood,amnionic fluid,lochia and etac as filthy and ominous materials,which will desecrate the inviolability,and drew up much abstinence of lunaria and birth.

古人认为从女阴里流出的血、、胎衣等是污的、不祥的,会明,故为之制订种种月经禁忌和生育禁忌。