人禀父母精血化生。故内经有曰。阳施阴化。谓之有子。圣济经言。方其受授之初。一月血凝。二月胚胎兆。三月
阳神为魂。四月阴灵为魄。五月五行分五脏。六月六律定六腑。七月七精开窍。八月八景具全。九月气足象成。十月百
神集备。至日满而生也。（又云。一月如珠露。二月若桃花。三月形象成。四月男女分。五月腑脏具。六月筋骨全。七月
魂生而动左。八月魄长而动右。九月三转身。十月足而生。此未知其所出。）其始有谓之妊者。以其阳始而阴任之也。有
谓之胚者。以其未成为器而犹坯也。有谓之胞者。以其已为正阳而阴
包之也。有谓之胎者。以食于母而为口颐也。有谓之娠者。以其有时而动也。有谓之怀者。以其有身而根据也。原夫此象
者。皆阳始阴任在有形之先。次由五行而后化成也。故曰。阴阳具而五行立矣。且阴之所任者。
壬也。一阳壬兆。则人乃肇生。命门主生气之原。精所藏焉。壬、阳水也。合丁之阴火而生丙。故有命门。然后生心。
心主血。神所藏焉。丙之阳火。合辛之阴金而生庚。故有心然后有肺。肺主皮毛。魄所藏焉。庚、阳金也。合乙之阴木
而生甲。故有肺然后生肝。肝主筋。魂所藏焉。甲为阳木。合己之阴土而生戊。故有肝然后生脾。脾生肉。意所藏焉。
戊为阳土。合癸之阴水而生壬。故有脾然后生肾。肾主骨。志所藏焉。故肾与命门一也。此阴阳五行。夫妇生化。自然
之理也。人之赋禀。自受气至胎化。自成形至生养。亦皆由焉。
人是由父母的精血结合而化生形成的。所以《黄帝内经》中说：阳施予阴，阴受纳阳，阴阳交合才能生育子女。《圣济经》记载：在受孕之初，第一个月血液凝结；第二个月胚胎的征兆显现；第三个月阳神化为魂；第四个月阴灵化为魄；第五个月五行分化出五脏；第六个月六律确定六腑；第七个月七窍开启；第八个月八种感官功能完备；第九个月气机充足，形体已成；第十个月各种神灵（生命机能）聚集完备，直到足月才出生。（又有一种说法称：第一个月像露珠一样微小，第二个月像桃花一样娇嫩，第三个月形象形成，第四个月男女性别区分，第五个月脏腑具备，第六个月筋骨健全，第七个月魂产生且身体向左动，第八个月魄生长且身体向右动，第九个月胎儿转身三次，第十个月足月而生。这种说法不知出自何处。）
起初称为“妊”的，是因为阳气开始发动而由阴血承载它。称为“胚”的，是因为尚未形成具体的器官形态，还像土坯一样未定型。称为“胞”的，是因为已经具备正阳之气而被阴包裹着。称为“胎”的，是因为依靠母体摄取营养来滋养口唇面部。称为“娠”的，是因为有时会出现胎动。称为“怀”的，是因为身怀六甲有所依托。推究这些名称的由来，都是在有形体质形成之前，阳气始动、阴血承载的结果，随后才由五行作用而化成形体。所以说，阴阳具备而后五行确立。
至于阴所承载的，是壬水。一阳初现于壬，人便开始了生命的肇始。命门主宰生气之源，精气藏于此。壬属于阳水，与丁之阴火相合而生丙火，因此有了命门之后才生出心。心主血脉，神志藏于此。丙为阳火，与辛之阴金相合而生庚金，因此有了心之后才生出肺。肺主管皮毛，魄志藏于此。庚属于阳金，与乙之阴木相合而生甲木，因此有了肺之后才生出肝。肝主管筋脉，魂志藏于此。甲为阳木，与己之阴土相合而生戊土，因此有了肝之后才生出脾。脾生成肌肉，意志藏于此。戊属于阳土，与癸之阴水相合而生壬水，因此有了脾之后才生出肾。肾主管骨骼，志意藏于此。所以肾与命门本质上是同一个东西。这就是阴阳五行、夫妇生化自然运行的道理。人的禀赋，从受气到胎化，从成形到出生后养育，也都遵循这一规律。
Human beings are generated from the transformation of their parents' essence and blood. Therefore, the *Huangdi Neijing* (Yellow Emperor's Inner Canon) states: "Yang exerts influence and Yin transforms; this is called having offspring." The *Shengji Jing* (Classic of Holy Relief) records: At the initial moment of conception, in the first month, blood coagulates; in the second month, the embryo begins to take shape; in the third month, the Yang spirit becomes the Hun (ethereal soul); in the fourth month, the Yin spirit becomes the Po (corporeal soul); in the fifth month, the Five Elements differentiate into the Zang organs; in the sixth month, the Six Harmonies determine the Fu organs; in the seventh month, the seven orifices open; in the eighth month, the eight faculties are complete; in the ninth month, Qi is sufficient and the form is established; in the tenth month, all divine functions are gathered and prepared, leading to birth upon completion of the term. (Another account says: In the first month, it is like a drop of dew; in the second, like a peach blossom; in the third, the image forms; in the fourth, male and female are distinguished; in the fifth, viscera and bowels are equipped; in the sixth, sinews and bones are whole; in the seventh, the Hun arises and movement is to the left; in the eighth, the Po grows and movement is to the right; in the ninth, the fetus turns three times; in the tenth, it is born fully formed. It is unknown where this account originates.)
Initially, it is called "Ren" (pregnancy) because Yang begins and Yin bears it. It is called "Pei" (embryo) because it has not yet formed distinct organs and remains like an unfired clay brick. It is called "Bao" (womb/uterus) because it has acquired true Yang energy and is wrapped by Yin. It is called "Tai" (fetus) because it receives nourishment from the mother to sustain the mouth and chin. It is called "Shen" (gestation) because there is occasional movement. It is called "Huai" (carrying) because the body is pregnant and supported. Tracing back to the origin of these terms, they all refer to the state before physical form exists, where Yang initiates and Yin supports, followed by transformation through the Five Elements. Thus it is said: When Yin and Yang are complete, the Five Elements are established.
Regarding what Yin bears, it is Ren Water. When one Yang appears in Ren, human life begins. the Mingmen (Gate of Life) governs the source of vital Qi, where essence is stored. Ren is Yang Water; combining with Ding Yin Fire, it generates Bing Fire. Thus, after the Mingmen, the Heart is generated. The Heart governs blood, and Shen (spirit) is stored within it. Bing is Yang Fire; combining with Xin Yin Metal, it generates Geng Metal. Thus, after the Heart, the Lung is generated. The Lung governs skin and hair, and Po is stored within it. Geng is Yang Metal; combining with Yi Yin Wood, it generates Jia Wood. Thus, after the Lung, the Liver is generated. The Liver governs sinews, and Hun is stored within it. Jia is Yang Wood; combining with Ji Yin Earth, it generates Wu Earth. Thus, after the Liver, the Spleen is generated. The Spleen produces flesh, and Yi (intention) is stored within it. Wu is Yang Earth; combining with Gui Yin Water, it generates Ren Water. Thus, after the Spleen, the Kidney is generated. The Kidney governs bones, and Zhi (will) is stored within it. Therefore, the Kidney and the Mingmen are essentially one. This is the natural principle of Yin-Yang and the Five Elements, and the generation and transformation of husband and wife. Human endowment, from receiving Qi to fetal transformation, from forming shape to postnatal nurturing, all follows this law.