Chapter 2　Women’s Physiological Characteristics

Other names of the uterus are bāo gōng （胞宫） , nǚ zĭ bāo （女子胞）, bāo zàng （胞脏）, zĭ zàng （子脏）, zĭ chù （子处）, xuè zàng （血脏）.

（1） Name: The actual use of the term “uterus” was frst seen in Shen Nong’s Classic of theMateria Medica—Fluoritum （ Shén Nóng Bĕn Căo Jīng—Zĭ Shí Yīng, 神农本草经·紫石英）, which states: “… governs wind-cold in the uterus of women”.

（2） Location: The uterus is located “in front of the rectum and behind the urinary bladder.

（3） Shape: The uterus, with one lower end and two branches at its upper, is divided in the middle into two parts, like a bowl, one reaching the lef side, and the other extending to the right side.

（4） Functions: The uterus mainly governs menstruation and gestates the fetus. In the Inner Classic （ Nèi Jīng, 内经）, it is referred to as an extraordinary fu-organ. This tells us its special functions and features: （1） It is hollow, like the other fu-organs in form; and it stores essence, blood and the fetus, similar to other zang-organs in function. （2） It has periodic storage and discharge function of both menstrual blood and the fetus. （3） It has no exteriorinterior matching function and has relationships with the other viscera.

（5） Relationships with Other Organs: The uterus is connected with the heart and kidney through the uterine vessels and the collateral network. It is said in Basic Questions—Discussion on Views of Febrile Diseases （ Sù Wèn—Píng Rè Bìng Lùn, 素问·评热病论） that “The uterine vessels are attributed to the heart and connect with the uterus”, and “The absence of menses is a result of obstruction of the uterine vessels.” Basic Questions—Discussion on ExtraDiseases （ Sù Wèn—Qí Bìng Lùn, 素问·奇病论） also states that the uterine collaterals are connected with the kidney. The Treatise on the Origins and Manifestations of Various Diseases （ Zhū Bìng Yuán Hòu Lùn, 诸病源候论） points out that an injury of the uterine collaterals can cause the falling of the reproductive organs, that is, prolapse of the uterus. This indicates that the uterine vessels and the uterine collaterals are the vessels and collaterals connecting the uterus and have a close relationship with women’s physiology. It is through the interactions of the uterine vessels and the uterine collaterals that the uterus coordinates and performs the functions of governing menstruation and gestation.

The cervical orifice is also called the female pudendum （ zĭ hù, 子户）, and refers to the position of the Cervical Os.

Zi chang generally refers to the uterus and the vagina. Prolapse of uterus refers to the uterus being unable to lift back into the vagina.

The vaginal orifice of the virgin （ yù mén, 玉门） is also called lóng mén （龙门） and bāo mén（胞门）. Bāo mén is used to refer to the vaginal orifice women who have already given birth to babies, while lóng mén refers to that in nullipara women, who have never had a child. The vaginal orifice of the virgin refers to that of unmarried women. Its position is under the urethral orifice （ yù quán, 玉泉）, at the vagina entrance. It corresponds to the hymen at the vaginal orifice of the external reproductive organs.

The vaginal orifce, also called the four sides （ sì biān, 四边）, refers to the female’s clitoris, major or minor labia, as well as the position of the vaginal vestibule, i.e. the anterior, posterior, lef and right sides of the vaginal orifce.

The pubic bone refers to the region of the pubic symphysis.

（1） Conception related to menstruation

The Chinese word for menstruation is yuè jīng （月经）, meaning bleeding from the uterus, which occurs monthly, regularly without change. Since it comes regularly like the moon’s waxing and waning, the tide’s fooding and ebbing, it is also called monthly sign （ yuè xìn, 月信）, monthly thing （ yuè shì, 月事）, monthly water （ yuè shuĭ, 月水） and monthly food （ yuè xùn, 月汛）.

i） Menarche—The menarche is the arrival of menstruation. A healthy female’s menarche generally occurs at the age of 14, but it is considered within normal range between the ages of 11 to 16.

ii） Menopause—Menopause is defined as the cessation of periods for 1 year and stopping permanently. It usually occurs in women of our country at about the age of 49, but it is also considered as normal within range of ages of 46 to 52.

iii） Menstrual Normal Manifestations:

Menstrual cycle: 28 ± 7days （21-35 days）

Menstrual period: 3-7 days.

Menstrual blood volume: 50-80 ml, generally. It may be less on the frst day, profuse on the second and third day, decreasing on the fourth day.

Menstrual blood color: Light red when it is scanty; dark red when it is profuse.

Menstrual blood nature: It is neither thin nor sticky, not coagulated, without blood clots and no special odor.

Concurrent Symptoms: Generally, there should be no obvious discomfort. Some women may have mild waist soreness, abdominal distention, breast distension and discomfort, and changes in emotions prior to and during menstruation.

iv） Special Menstrual cycles:

Sometimes, even under normal conditions, menstruation may occur in cycles other than monthly. Such changes in menstruation are regarded as normal phenomena, not morbid.

Bimonthly Menstruation （ bìng yuè, 并月）: Under normal conditions, menstruation may occur once every other month. This is referred to as bimonthly menstruation.

Trimonthly Menstruation （ jū jīng, 居经）: There is no disease, but menstruation occurs once three months. This is referred to as tri-monthly menstruation or seasonal menstruation （ jì jīng, 季经）.

Yearly Menstruation （ bì nián, 避年）: Under normal conditions, menstruation occurring once a year is known as yearly menstruation.

Latent Menstruation （ àn jīng, 暗经）: If menstruation never occurs during the entire lifetime of a woman, but she is able to conceive, it is referred to as latent menstruation.

Menstruation during Pregnancy （ jī jīng, 激经）: In some cases, menstruation may occur regularly in the initial months of pregnancy without afecting the fetus. It is referred to as menstruation during pregnancy, or gòu tāi （垢胎） or shèng tāi （盛胎）.

（2） The Mechanism of Menstrual Production

Menstruation is a physiological phenomenon where the organs, the reproductionstimulating essence, the channels, qi and blood together affect the function of the uterus. In other words, qi and blood generated from the viscera are carried to the uterus through channels （ chong and ren mai, as well as du mai） under the action of the reproductionstimulating essence, and are discharged periodically, this being referred to as the menses. Briefly speaking, the menstrual cycle is the joint effort of the kidney qi, the reproductionstimulating essence, the chong mai, and ren mai, which make the qi and blood of the uterus become full and overflow. In this process, kidney qi is the predominant factor, the reproduction-stimulating essence is the driving force, and the chong mai and the ren mai are the passageways, the uterus is the location, and the qi and blood are the material basis. That is: kidney qi excess → the arrival of the reproduction-stimulating essence → chongmai being abundant and ren mai connected → blood filling the uterus and the arrival of menses.

（3） Menstrual Cycle Regulation

The menstrual cycle has unchanging periodicity and rhythm. How are these characteristics formed and how is it regulated? Chinese medicine believes that this kind of periodicity and rhythm reflect the cyclical growth and decline of yin and yang of the kidney and the waxing and the waning of qi and blood in the process of women’s reproductive physiology. Moreover, at different stages of a menstrual cycle, there are diferent physiological processes. Modern Chinese medicine has explored the mechanism of cyclic formations and its regulation from different angles. Currently there are several types of doctrines as follows: 1） correspondence between human beings and nature, 2） yinyang conversion of the kidney, 3） the reproductive axis: kidney-reproduction-stimulating essence- chong and ren mai-uterus, 4） the axis of the brain-kidney-reproduction-stimulating essence- chong and ren mai-uterus.

（1） Defnition

Leukorrhea has both a broad and narrow meaning. Leukorrhea, in its broad meaning, refers to all the gynecologic diseases below the dai mai （belt vessel）. Dài xià yī （doctors treating leukorrhea diseases） is the name for a gynecologist in ancient China.

Leukorrhea, in its narrow meaning, refers specifically to the sticky fluid that is discharged from the vagina; and it can be divided into physiological and pathological types.

Physiological leukorrhea, in healthy women with mature sexual function, is a type of fuid without color or odor, sticky and thin. It is discharged from the vagina and moistens the vulvae and the vagina.

Pathological leukorrhea refers to the abnormal changes in the volume, color, consistency and smell of the vaginal discharge. They may be classifed as yellow, white, green, red, or fve-colored leukorrhea.

（2） Leukorrhea Production Mechanism

Physiological leukorrhea is a kind of human essence and fuid. It is, in fact, the kidney essence that descends to moisten the reproductive organs. Normally essence is stored in the kidney; but in the presence of tiān guĭ, it will be transformed into menstruation and periodically normal discharge. “The kidney is an organ that controls water and body fuid”. Therefore, the production of leukorrhea is closely associated with the kidney. In addition, it also has important relationships with the three vessels of ren mai, du mai, and dai mai. This is because ren mai is a sea of yin channels, governing the general yin essence. Yin essence also needs the warmth of du mai and the regulation of dai mai to be transformed into body fuid, which bears downwards and moistens the vagina at the right time and in the right amount.

Therefore, the mechanism of leukorrhea production can be summed up as follows. Under the condition of abundant kidney qi, and motivated by the reproduction-stimulating essence, yin essence from the five zang-organs and the six fu-organs descends to the uterus through ren mai and moistens it, forming leukorrhea. This process also requires the warming and transformation function of du mai and the regulating force of dai mai.

（1） Defnition

Gestation （pregnancy） refers to the time from conception up until childbirth, a period when the fetus is nourished, grows and develops inside the womb, culminating in childbirth. In the classics of Chinese medicine, it has other names like chóng shēn （double body, 重身）, huái zĭ （having a baby, 怀子）, yŏu zĭ （having a baby, 有子） and so on.

（2） Manifestations

Detailed records of human pregnancy in Chinese medicine can be dated back to a very early time. Methods of Monthly Fetal Nourishment （ Zhú Yuè Yăng Tāi Fă, 逐月养胎法） by Xu Zhi-cai during the Bei Qi Dynasty （550-577 AD） says, “In the frst month of pregnancy, the embryo has started its development; the second month, fat develops; the third month, the fetus starts to develop; the fourth month, the fetus takes form, the fifth month, the baby can move; the sixth month, tendons and bones are developed; the seventh month, hairs are present; the eighth month, viscera are complete; in the ninth month, qi of food essence enters the stomach; in the tenth month, all spirit and mind are ready and when the date is due, there will be delivery”.

Gestation can be divided into Trimesters （each three months）:

Early Gestation （First Trimester 1st to 3rd month of pregnancy）: 1） Menstrual suppression. 2） Morning sickness: picky appetite, morning dizziness, nausea and vomiting. 3） Enlargement of the breasts, dark discoloration of nipples and areolae. 4） Urine and blood HCG assays are positive. 5） The six pulses feel slippery and fluent, and the chi part of the pulse feels continuous. 6） Gynecological Examination: The vagina and cervix become purplish blue in color; the uterus is enlarged and round, as well as sofened. 7） The enlarged uterus presses against the urinary bladder and provokes frequent urination.

Middle Gestation （Second Trimester, 4th to 6th month of pregnancy）: 1） The abdomen gradually rises, and the fetal body gradually grows. The pregnant woman is conscious of fetal movement. 2） The heart sounds can be heard, the whole fetus and fetal movement, as well as amniotic fluid, can be seen on ultrasound. 3） There is an increased vaginal discharge.

Late Gestation （Third Trimester, 7th to 10th month of pregnancy）: 1） As the baby continues to grow and presses upwards towards the lungs and stomach, breathing becomes shallow and quick. Excessive food intake causes a sensation of fullness and distension in the stomach. 2） Because the uterus enlarges and presses downwards onto the inferior vena cava, it causes the blood flow to become obstructed and mild edema may appear in the lower limbs, which disappears afer rest.

（3） Mechanism of Gestation

Simply speaking, the successful combination of women’s and men’s reproductive essence gestates in the uterine cavity. It is said, “When men’s essence is strong, and women’s essence is regular, it is the time of having an ofspring”.

Conditions: The woman’s body has ripened and begun to menstruate. This indicates that the kidney qi is abundant, the reproduction-stimulating essence is ready, and the functions of chong and ren mai are normal. These are the prerequisites for a woman to be able to conceive and become pregnant. During the time of yīn yūn （ovulatory phase,絪緼） or dí hòu （ovulatory phase, 的候）, the two essences are combined, and conception occurs.

Modern understanding of physiology finds that if the male’s reproductive function is normal, and the woman has regular and normal ovulation, unobstructed fallopian tubes and appropriate intrauterine environment, she is able to conceive if she has sexual intercourse at the time of ovulation. Ovulation usually occurs 14 days prior to beginning of the next period, and may be accompanied by a dull pain on one side of the lower abdomen and more clear and stretchy vaginal discharge. Successful gestation also depends on the functions of other hormones.

Childbearing and feeding are composed of three stages: delivery, childbed, and breast feeding.

（1） Delivery: Delivery refers to the process of the fetus and placenta being completely delivered from the maternal body, afer a period which is variously referred to as, about 288 days from conception, or 40 weeks or ten months.

Calculation of Expected Date of Delivery: The expected due date of delivery is calculated from the frst day of the last menstrual period, its month number, adding nine （or minus three）, its date plus seven. For example, if the last menstrual period occurred on March 12 ^th, then the expected due date of delivery is December 19 ^th. If the lunar calendar is used, then 14 days should be added to its date.

Delivery signs: The term delivery refers to the time two weeks before or after the expected date of delivery. There will be a slightly bloody and mucous secretion from the vagina when the cervical plug is released. When contractions begin there is paroxysmal pain in waist and abdomen [this should be distinguished from false labor （ Nòng Tāi, 弄胎） ], the sensation of downward pressure in the lower abdomen which gradually intensifies. When the waters break, amniotic fluid will flow out, and the cervical orifice （ zĭ mén, 子门）will completely open. As the baby passes down the passage, there is a strong stretching sensation in the vulva （ yīn hù, 阴户） and anus.

In modern medicine, labor is described in three stages:

Stage One: （Cervical Dilatation）: The first stage begins with the onset of uterine contractions, culminating in full cervical dilatation. For first pregnancies, it may take anywhere from 11 to 12 hours. For multiparous women, it may take 6 to 8 hours.

Stage Two: （Delivery of the Infant）: The second stage begins with the full cervical dilatation and fnishes with the delivery of the infant. For frst-time mothers, this can take from two to three hours. For second babies and beyond, the second stage ofen lasts only a few minutes, or up to an hour.

Stage Three: （Passage of the Placenta）: The third stage of labor begins with the delivery of the infant and finishes with the passage of the placenta. This can take from 5 to 30 minutes.

Factors that affect labor and delivery include energy, birth canal, fetus （size and position） and the woman’s mental state.

（2） Puerperium

The six weeks following delivery is called the puerperal period. During this stage, the reproductive organs will begin to be restored to their pre-pregnancy condition, i.e., the uterus decreases in size from 1000 g to 50 g. Its volume decreases 1000 times or so. In addition, the vulva, the vagina and the fallopian tubes all revert to the functional status prior to pregnancy. The ovaries may not revert however while breast feeding continues.

Physiological Characteristics in Puerperium: A mild fever and spontaneous sweating may occur within 1 to 2 days afer the delivery. This is related to damage to the yin blood caused by the exertion and sweating of labor, obstetric trauma, or excessive bleeding afer labor. This follows the physiological phenomenon “When yin-blood suddenly becomes defcient, yang qi foats easily.” Afer several days of rest and good nutrition, the body will recover, the fever will spontaneously resolve and require no special treatment.

Lochia: Lochia is the residual blood and turbid fluid in the uterus that is discharged from the vagina after delivery. Its complete discharge requires about three weeks. In general, the amount of lochia is not more than that of past menstrual periods. During the frst week, it is mainly dark red blood; during the second week, it turns to a light red color; and during the third week, it becomes light yellow. Its amount gradually decreases and there is no special odor.

（3） Breast-feeding

Advantages of Breast-feeding: Milk is generated by and transformed from maternal qi and blood. For the neonate, maternal milk is the best possible food. It contains appropriate nutrition and is easily digested by the infant. What’s more, it contains a large quantity of immunoglobulin, some of which is benefcial for the baby’s entire life. For the mother, breast-feeding also promotes uterine contraction, decreases postpartum bleeding, and is good for the recovery of mother’s body shape. In addition, breast-feeding facilitates a bonding of the mother and the infant as early as possible.

New Conceptions of Breast-feeding: 1） Early sucking: Allowing the infant to suck nipple within 30 minutes afer delivery to stimulate milk secretion as early as possible. 2） Breast-feeding: Breast-feed according to the baby’s needs rather than rigidly defining the time and frequency of breast-feeding. Breast-feed when the baby is hungry, or afer the infant wakes up. Breast-feeding, according to the mother’s requirement, dictates that when the mother feels distention in the breast, no mater whether the infant is sleeping or awake, she can breast-feed the child.

Methods of Breast-Feeding: It is important to clean the nipples and the breast well. When the breast feels hard and is distended, first apply a hot pack compress; and then massage the breast, so as to make the milk flow smoothly. The primipara should breastfeed about ten minutes each time, but no more than 15 minutes to avoid nipple cracking or soreness. Afer fnishing breast-feeding and emptying the breast, carry the infant in one’s arms upright, gently tapping its back to make the air vent and to prevent vomiting of milk.