From antiquity to modern times successive generations of physicians have had various and sometimes conflicting views of the term Tian Gui. Some experts have explained Tian Gui as Essence Jing, such as the Qing dynasty physician Shen Yao Feng who stated:”Tian Gui is female Essence”. This would mean that Tian gui only exists in females. But the seminal text on Chinese Medicine, the Su Wen in the first chapter “Shang Gu Tian Zhen Lun Pian” also states:”In females at the age of seven the Kidney Qi is in fullness, the teeth change and the hair grow, at two times seven the Tian Gui reaches (matures), the conception vessel is open, the Sea of Blood Vessel Chong Mai is full and the monthly affair flows down in a timely manner, hence she can have children…..;
“in males at the age of 8 the Kidney Qiis in repletion, the hair grows and the teeth change, (second teeth grow), at two times 8 the Kidney is abundant, the Tian Gui has arrived, the Essence Qi overflows, (when) the Yin and Yang unite, children can be conceived…..”
This clearly illustrates that both male and female have Tian Gui and that it influences the human growth, development and production of a type of Yi Essence in the reproductive organs. The fact that the menstrual cycle starts at fourteen indicates thaqt the ovaries already have developed their normal physiological function and also that ovulation is taking place.
In the male at age 16, the Kidney Qi is sufficient to create spermatic fluid, so if at that time a male and female have sexual intercourse, pregnancy may ensue. Based on these facts, what exactly is Tian Gui and what kinds of functions does it have?
1.The Tian Gui is the equivalent to certain hormones of contemporary medicine. The growth, development and aging rely to a large degree on the regulatory function of the endocrine system, such as the anterior lobe of the pituitary glands, which secrets gonadotropic hormone, thyroid stimulating hormones, human growth hormones and prolactin etc. If the hypothalamic and pituitary secretions are normal, then the human growth and development remain normal, this is what the Nei Jing refers to as “three times seven, the Kidney Qi is average, thus the teeth have fully grown and matured to the fullest, at four times seven the tendons and bones are firming and the hair has reached its full maturation, the body is strong and healthy..” which fully corresponds to the normal physiological stages of hormonal development.
“At seven times seven, the Conception vessel is vacuous, and the Chong Mai weak and decreased, the Tian Gui is exhausted…” this quote points out that in women after the age of 49 the sexual functions have declined, menstruation stops, procreation has ceased, the breasts, uterus and vagina gradually shrink and withdraw from beginning of menopause ‘til full cessation of menstruation.
As for the male, “…at seven times eight (age 56) the Liver Qi declines, the tendons and ligaments cannot move, the Tian Gui ceases, the sperm is reduced, the Kidney Qi weakens, the body has reached its limit…” This indicates that after reaching the age of 56 the reproductive system gradually declines.
2.The Tian Gui is a product of the Kidney Qi. If the Kidney Qi is abundant, then the Tian Gui arrives, if the Kidney Qi is weak, the sexual capacity will equally weaken and decrease, and the Tian Gui is depleted. The Tian Gui is intimately related to the abundance or weakness of the Kidney Qi. If the Kidney Qi is vigourous and abundant, then periodic changes in the sexual realm are possible. If the Kidney Qi is weak, then the sexual capacity will correspondingly decline and weaken. This illustrates that the Tian Gui is a product of the Kidney Qi, and the production of Tian Gui must be preconditioned by trhe fullness and abundance of Kidney Qi.
3.The Tian Gui is governed by the nervous system. The Su Wen “Theory on judging febrile diseases ping re bing lun states: “If there is no monthly period, then the Uterus Vessel (bao mai) is closed.” The Uterus Vessel Bao Mai originated from the heart and connects with the uterus, today (when) the Qi presses upward into the Lung, then the heart Qi is unable to move downward, hence menstruation doesn’t flow down. This explains the relationship of amenorrhea and the Heart; the functions of the Heart as described by Chinese Medicine can be likened to some aspects of the central nervous system in modern biomedicine.One example to illustrate the above might be seen in a women that is suddenly afflicted by a abnormally strong emotional shock or frightful episode, which may lead to amenorrhea.
To sum up, the above, the Tain Gui is directly related to the Kidney and is closely integrated and similar to the modern biomedical endocrine and urinary system. The Tian Gui is associated with the material basis of the male and female reproductive system.