The cycle of menstruation differs between Western Medicine and the Four phases within Chinese Medicine. A normal menstruation is also known as an Eumenorrhoea that lasts 3 to 7 days within Western Medicine. An average range of 10-80ml of blood is the normal loss of blood within menstruation.  

Symptoms of menstruation are: 

  • Cramps within the Abdomen, back and upper thigh cramps. 
  • Clots
  • Breast tenderness
  • Irritability

In Chinese medicine, the act of bleeding in menstruation is controlled by the Liver – Blood and the Penetrating Vessel/ Chong Mai.

Follicular Phase

In Western Medicine there are two phases of the menstrual cycle and the first is the Follicular Phase. The pituitary glands release FSH, a follicle stimulating hormone that releases oestrogen from the ovaries. The lining of the uterus thickens, and follicles develop within the ovaries. A singular follicle that survives the changes of hormones matures into a Graafian follicle. The mature follicle then produces an ovum that stimulates ovulation and oestradiol, a steroid hormone. 

In Chinese medicine, the Follicular phase is controlled by the Liver- Blood, the Kidneys and the Directing Vessel (Ren Mai). Oestrogen forms a new layer of endometrium in the Uterus and encourages crypts to produce cervical mucus. 


In maturity, the high levels of oestradiol cause the release of LH from pituitary glands. LH begins its cycle on an average of the 12th day of the cycle and lasts around 48 hours. LH further matures the egg and releases a second oocyte, which then develops into an otis and a mature ovum with a diameter of 0.2mm. The egg then moves into the fallopian tube. Fertilization occurs in the ampulla, the widest area of the fallopian tube, and disintegrates if fertilization does not happen. On the other hand, if the egg is fertilized, the egg will begin embryogenesis.

In chinese medicine, ovulation is controlled within the Kidney Yin and Yang, the Directing/Ren Mai Vessel, and the Penetrating/Chong Mai Vessel.

Luteal Phase

The second phase is the Luteal Phase, it starts at the phase of ovulation and ends the day before the next period. This phase lasts on average 14 days, and must be at day 10 to support pregnancy. When the follicle expels the egg, it turns into a corpus luteum, which increases progesterone and endometrium changes. Corpus Luteum means yellow body, named after the fact that the color is yellow. It produces progesterone for 12 to 15 days which thickens the uterus lining. The increase in progesterone helps the body prepare for pregnancy. The absence of pregnancy within 2 weeks causes the ovum to shrink in size and oestrogen and progesterone levels drop. The hormone imbalance will cause the uterus lining to shed.

In Chinese medicine, there are two aspects of the Luteal Phase. The first part involves the Minister fire because of the change in temperature after ovulation, the Kidney Yang and the Governing Vessel. The second part of the Luteal Phase involves Liver – Qi, Liver-Blood, and the Penetrating Vessel

Hypothalamus- Pituitary-ovarian axis

The menstrual cycle is primarily the relationship between the hypothalamus, pituitary and the ovaries. The hypothalamus releases the gonadotropin (GnRH) in the Kidneys and ovaries that stimulates the secretion of FSH and LH. FSH encourages the development of follicles and LH stimulates corpus luteum. The Governing Vessel involves the Yang of the menstrual cycle and reaches the Brain as well as the ovaries, whereas the Directing Vessel involves the Yin of the menstrual cycle and only reaches the ovaries. Oestrogen is produced by Kidney Yin and is considered Yin because of the moisture it produces such as mucus and the fluids within the cervical glands. On the other hand, progesterone is produced by Kidney Yang and is considered Yang since it dries the cervical mucus.

In men, the GnRH stimulates the Leydig cells in the testes and causes the secretion of LH. Afterwards, the LH secreted allows the Leydig cells to produce testosterone levels. The pituitary glands in men produce FSH. FSH and testosterone encourage the production of Sertoli cells to develop sperm.

Four phases

Within Chinese Medicine, menstruation is the ebb and flow of Kidney Yin and Yang, and the vertical relationship between the Heart and the Kidney. It is necessary for the Heart- Qi to descend to the Kidneys in order to stimulate ovulation and menstruation. The heart is the fire and the kidneys are the water. It is necessary for fire and water to talk to each other. Read the Five Element article on our website to find more about the connection between Water and Fire. There is a switch from Yang to Yin when the menstruation cycle occurs and a switch from Yin to Yang when ovulation occurs. 

The Directing and Governing Vessels control the ebb and the flow of the Yin and the Yang. The stepping vessels/ qiao mai balance the Yin and Yang, while the Yin and Yang are controlled by the Linking Vessels. The vessels are not the primary role of the menstrual cycle because they do not flow through the uterus.

The Bleeding Phase

The first phase is the menstrual or the bleeding phase, where Yang, Qi, and Blood move down due to the Heart-Qi. It takes place in the Xiao Fu area of the abdomen under the umbilicus. The Penetrating Vessel/Chong Mai, Directing Vessel and the Liver– Blood influences the phase. The descent of the Yang is necessary, otherwise the period starts late or not at all. An excess of Yang or fast dissension of Yang may cause an early and heavy period. Women with minimal blood loss are susceptible to retention of the menses or endometriosis. 

Since Blood descends during this phase, the best treatment involves the invigoration of the Blood. In a normal flow the herbs used for treatment include Chuan Niu Xi, Ze Lan and Dan Shen. In a heavy flow, however, the herbs San Qi Radix Notoginseng, Pu Huang Pollen Typhae, and Qian Cao Gen Radix Rubiae move and stop blood at the same time. 

Post Menstrual

The second phase is the postmenstrual phase where Yang decreases and Yin increases at high rates. Ovulation depends on the Yin ascension and Yang descension. If Yin does not increase the process is delayed, and if Yang does not follow its path down, the process of ovulation may happen earlier. Blood and Yin are empty in comparison to other phases because of the blood loss during the first phase. In this second phase, the menstrual cycle looks for a balance. In this phase, the Yin grows, which in turn increases Kidney-Yin. The Uterus and follicles receive nourishment from the Essence/ Jing as it matures in this phase. The shift in Yin and Yang are integral for a balance within the body. The lack of shift means they are stagnant and there is an obstruction in the menstruation cycle. The growth of Yin promotes vagina fluids and the cervical secretions. 

Since Blood is fairly empty, the best treatment is the nourishment of the Blood and since menstrual blood is connected to Tian Gui, there is a tonification of the Kidneys. 


The third phase occurs in the sides of the lower abdomen also known as the Shao Fu area due to the Penetrating Vessel. The movement of Qi and Blood may produce bloating within the Shao Fu area, mood swings, and breast distention. The cervix secretes a wet and slippery substance due to the influence of the Kidney and the Directing Vessel/Ren Mai. Then at the beginning of ovulation it secretes a viscous, transparent substance. After the first day of ovulation, secretion thickens and less is released. The end of ovulation there is a sticky secretion. 

The Os In The Cervix

The os of the cervix opens when oestrogen levels rise and begins producing fertile mucus. In ovulation, as the os opens, the mucus changes as it clings to the cervix. When fertility is at its peak, mucus is wet and clear, due to the Kidney Yin and Essence. If there is a lack of secretion, it may be a sign of Kidney Deficiency. Heart-Qi propels the cycle of the Yin and Yang as well as the discharge of the ovum from the ovaries

In this third phase, Yin decreases and Yang increases. However if they do not, pathology will occur through dampness and phlegm in the Uterus. Excess in Yin and deficiency in Yang that could delay ovulation, while the alternative would cause ovulation to occur early. 

In the third phase, the tonification of the Kidneys, removal of Dampness, tonification of the Spleen, and the tonification of the Governing, Directing and Penetrating Vessels are the best forms of treatment.

The Fourth Phase

In the fourth phase, Yang increases at a fast rate and produces warmth in the Uterus to facilitate implantation in the endometrium. It removes the Yin from the Uterus to avoid Cold, Phlegm, Dampness and Blood stasis. Yin pathogens include endometriosis where Blood stasis is treated, and polycystic ovary syndrome where Damp Phlegm is treated.

In the fourth phase, the best treatment involves the transference of Qi, movement of Blood, warm the Uterus, and removing the pathogenic factors of excess Yin such as cold and Damp-Phlegm.