Amenorrhea is usually caused by congenital defect, insufficiency of kidney qi, essence and blood; or by multiparity and excessive sexual life which impair the liver and kidney leading to deficiency of essence and blood and hypofunction of the thoroughfare and conception vessels; or by improper diet, overstrain and anxiety which damage spleen qi and leading to insufficiency of transformation; or by constitutional weakness, or serious disease and prolonged duration of illness, multiparity, loss of blood affecting fluid, deficiency of blood in the thoroughfare and conception vessels; or by impairment of the liver due to rage, stagnation of liver qi, unsmooth flow of qi which lead to stagnation of the thoroughfare and conception vessels, or by improper care during menstruation, or exogenous pathogenic factors attack, or internal impairment due to intake of uncooked and cold foods which result in cold coagulation in the thoroughfare and conception vessels; or by obesity, internal exuberance of phlegm-dampness, or failure of spleen yang to transport, leading to accumulation of dampness into phlegm in the thoroughfare and conception vessels as well as in the uterine collaterals.