程鸣谦曰∶信褚氏之言，则人有精先泄而生男，精后泄而生女者，何欤？信东垣之言，则有经始断，交合
生女，经久断交合生男。亦有四五日以前交合无孕，八九日以后交合有孕者，何欤？俞子木又谓∶微阳不能
射阴，弱阴不能摄阳。信斯言也。世有 羸之夫，怯弱之妇，屡屡受胎。而血气方刚，精力过人者，往往有终
身不育，竟至乏嗣，独何欤？丹溪论治，专以妇人经水为主。然富贵之家，侍外家亦多，其中宁无月水如期者？
又有经前夫频育，而娶此以图易，则不受胎。岂能受于此。而不能受于彼耶？大抵父母生子，如天地生物。《易》
曰，坤道其顺乎承天而时行。知地之生物，不过顺承乎天，则知母之生子，亦不过顺承乎父而已。知母之顺承
乎父，则种子者果以妇人为主乎，以男子为主乎？若主男子，则不拘老少强弱，康宁病患，
精之易泄难泄，只以交感之时，百脉齐到为善耳。若男女之辨，不以精血先后为拘，不以经尽几日为拘，不以夜
半前后交感为拘，不以父母强弱为拘，只以精血各由百脉齐到者别胜负耳。故精之百脉齐到胜乎血，则成男。
血之百脉齐到胜乎精，则成女矣。
李东璧曰∶《易》云，一阴一阳之谓道。男女媾精，万物化生。干道成男，坤道成女。此盖言男女生生之
机，亦阴阳造化之良能也。齐·褚澄言血先至裹精则生男，精先至裹血则生女。阴阳均至，非男非女之身。精
血散分，骈胎品胎之兆。《道藏》言∶月水亡后一三五日成男，二四六日成女。东垣言∶血海始净一二日成男，
三四五成女。《圣济经》言∶因气而左动，阳资之则成男；因气而右动，阴资之则成女。丹溪乃非褚氏而是东
垣，主《圣济》左右之说立论，归于子宫左右之系，其说可谓悉矣。窃谓褚氏未可非也，东垣亦未尽是也。
盖褚氏以精血之先后言，《道藏》以日数之奇偶言，东垣以女血之盈亏言，《圣济》、丹溪以子宫之左右言。
各执一见，会而通之，理自得矣。夫独男独女之胎，可以日数论，骈胎品胎之感，亦可以日数论乎？稽之史载，
一产三子四子，有半男半女，或男多女少，男少女多，则一三五日为男，二四六日为女之说，岂其然哉。岂有
一日受男，而二日复受女之理乎？此褚氏、《圣济》、丹溪主精血、子宫左右之论为有见。而《道藏》、东垣
日数之论为可疑矣。叔和《脉经》以脉之左右浮沉，辨猥生之男女；高阳《脉诀》，以脉之纵横逆顺，别骈品
之胎形，恐亦臆度之见，而非确论也。
慎斋按∶以上七条，序受胎辨男女之分，有不同之论也。经云，左右者，阴阳之道路。男女者，阴阳之仪
象。故阴阳和，而万物生。夫妇合，而男女形。可见男女之生，未有不本于阴阳之理者也。故褚澄以精血先后分男
女，东垣以日数奇偶分男女，鸣谦以百脉齐到分男女，皆为理之未确。故丹溪议褚李二公之论为未融，而以《易》
道之干元资始，坤元资生为据，娄全善所以叹为造极精微，发前人未发是矣。若子宫分左右，而以两歧辨男女，
夫子宫为命门，女子系胞，形如合钵，何尝两歧，而分左右则是有两子宫，此说为凿空无据。《圣济》是论左
右阴阳之气分男女，未尝以子宫有左右之分也。况男女交媾时，均有其精，何尝有血。褚氏、东垣、丹溪，俱
以精血混言，几见男女媾精，而妇人以血施也。前贤之论多谬，僭辨之。
程鸣谦说：如果相信褚氏的说法，那么先泄精而生男孩，后泄精而生女孩，这是为什么呢？如果相信李东垣的说法，那么月经刚停止时交合生女孩，月经结束后一段时间再交合生男孩。也有在月经来潮前四五天交合不能受孕，而在八九天后交合却能受孕的情况，这又是为什么呢？俞子木又说：微弱的阳气不能射入阴中，虚弱的阴气不能摄持阳气。如果相信这些话，世上那些身体瘦弱衰败的丈夫和怯懦虚弱的妻子，却屡屡能够受孕；而血气正旺盛、精力过人的人，往往终身不育，甚至断绝后代，这究竟是什么原因呢？丹溪论述治疗，专门以妇女的月经为主。然而富贵人家，侍奉外室（妾）的也很多，其中难道没有月经按时来潮的吗？又有之前频繁生育的妇人，改娶此妇以求易孕，结果却不受孕。难道能在此处受孕，而不能在彼处受孕吗？大抵父母生子，就像天地化生万物。《易经》说，地道柔顺，承奉天道而按时运行。知道大地化生万物，不过是顺承天道，就知道母亲孕育子女，也不过是顺承父亲罢了。知道母亲顺承父亲，那么种子（受孕）这件事，究竟是以妇人为主，还是以男子为主呢？如果以男子为主，那么不论老少强弱、健康或患病，只要看精气容易泄出还是难以泄出，只以交感之时，百脉之气同时到达为最好。如果要辨别男女，不拘泥于精血到来的先后，不拘泥于月经结束后的天数，不拘泥于半夜前后交合的时间，不拘泥于父母的强弱，只以精和血各自由百脉同时到达者谁占优势来区分胜负罢了。所以，如果精的百脉齐到胜过血的百脉齐到，就生成男孩；如果血的百脉齐到胜过精的百脉齐到，就生成女孩。
李东璧说：《易经》讲，一阴一阳交互作用叫做道。男女交合精气，万物由此化生。乾道成就男身，坤道成就女身。这大概是讲述男女生生不息的机理，也是阴阳造化的良能。南齐·褚澄说，血先到包裹精则生男孩，精先到包裹血则生女孩。阴阳均等到达，则形成非男非女的身体。精血分散分布，则是双胎或多胎的征兆。《道藏》说：月经干净后的一、三、五日受孕成男，二、四、六日受孕成女。李东垣说：血海刚刚干净的一二天受孕成男，三四五天受孕成女。《圣济经》说：因气机向左动，阳气资助则成男；因气机向右动，阴气资助则成女。朱丹溪否定褚氏而肯定李东垣，依据《圣济经》左右之说立论，归结于子宫左右的系带，他的说法可以说是详尽无遗了。我私下认为褚氏不可全盘否定，李东垣也未完全正确。大概褚氏是从精血到来的先后来说，《道藏》是从日数的奇偶来说，李东垣是从女子血的盈亏来说，《圣济经》和朱丹溪是从子宫的左右来说。各自坚持自己的见解，融会贯通它们，道理自然明了。至于独男独女的胎儿，可以用日数来论述，但双胎或多胎的形成，也可以用日数来论述吗？考察史书记载，一次分娩三个或四个孩子，有半男半女，或男多女少，或男少女多，那么“一三五日为男，二四六日为女”的说法，难道是真实的吗？难道有一天受胎生男，第二天又受胎生女的道理吗？因此，褚氏、《圣济经》、朱丹溪主张的精血、子宫左右之论是有见地的，而《道藏》、李东垣的日数之论是值得怀疑的。王叔和《脉经》通过脉象的左右浮沉，来辨别杂生（指非正常单胎或性别不明）的男女；高阳《脉诀》，通过脉象的纵横逆顺，来辨别双胎或多胎的胎形，恐怕也是臆测之见，而非确切的结论。
慎斋按语：以上七条，叙述了关于受胎辨别男女的不同论点。《内经》说，左右，是阴阳运行的道路。男女，是阴阳的形象表现。所以阴阳调和，万物就产生；夫妇结合，男女的形体就形成。可见男女的出生，没有不基于阴阳道理的。所以褚澄用精血先后区分男女，李东垣用日数奇偶区分男女，程鸣谦用百脉齐到区分男女，这些观点都有不够确切之处。因此朱丹溪评议褚氏、李氏两位公子的理论不够圆融，而以《易经》中乾元资始、坤元资生的道理为依据，娄全善因此赞叹其达到精微极致，发挥了前人未曾阐发的见解，这是正确的。如果说子宫分左右，并用两歧来辨别男女，子宫就是命门，女子胞宫形状像合起来的钵，何曾有两歧，如果说分左右那就是有两个子宫，这种说法是凭空捏造没有根据的。《圣济经》讨论的是左右阴阳之气分男女，并没有说子宫有左右之分。况且男女交媾时，都有精气，何曾有血？褚氏、李东垣、朱丹溪，都混用精血而言，哪里见过男女交合精气，而妇人只用血来施予的呢？前贤的言论大多有误，我冒昧加以辨析。
Cheng Mingqian stated: If one believes in Chu's theory, then why does seminal emission occurring first result in a male child, while emission occurring later results in a female child? If one believes in Li Dongyuan's theory, then why does intercourse immediately after the cessation of menstruation yield a female, whereas intercourse after a longer interval yields a male? Furthermore, there are cases where intercourse four or five days before menstruation fails to conceive, yet intercourse eight or nine days later succeeds. Why is this? Yu Zimu further asserted: "Weak Yang cannot penetrate Yin, and weak Yin cannot grasp Yang." If these words are believed, then why do frail and debilitated husbands and timid and weak wives frequently conceive, while men with robust blood and Qi (vital energy) and abundant vitality often remain sterile and fail to produce heirs? Danxi's discussion on treatment focuses primarily on the woman's menstrual flow. However, in wealthy households, concubines are common; surely not all of them have regular menstruation? Moreover, a woman who has frequently given birth previously might fail to conceive when married to a new husband seeking fertility. How can she conceive with him but not with the previous partner? Generally speaking, parents giving birth to children is akin to Heaven and Earth generating all things. The *I Ching* (Book of Changes) states: "The Way of Kun (Earth) is its submission, receiving from Tian (Heaven) and acting according to time." Knowing that Earth generates all things by submitting to Heaven, we know that a mother bearing children also submits to the father. Understanding that the mother submits to the father, we must ask: Is conception primarily dependent on the woman or the man? If it depends on the man, regardless of age, strength, health, or illness, and whether his essence is easy or difficult to emit, the key is that at the moment of sexual union, the Qi of the hundred vessels arrives simultaneously. To distinguish between male and female, one should not be constrained by the sequence of essence and blood arrival, the number of days since menstruation ended, the time of night (before or after midnight), or the strength of the parents. One should only distinguish based on which—essence or blood—arrives via the hundred vessels more dominantly. Thus, if the simultaneous arrival of essence via the hundred vessels surpasses that of blood, a male is conceived; if the simultaneous arrival of blood surpasses that of essence, a female is conceived.
Li Dongbi stated: The *I Ching* says, "One Yin and one Yang constitute the Dao (Way)." When male and female unite their essence, all things are transformed. The Way of Qian (Heaven) forms the male, and the Way of Kun (Earth) forms the female. This describes the generative mechanism of male and female, and the virtuous capacity of Yin-Yang creation. Chu Cheng of the Southern Qi dynasty said: If blood arrives first and envelops the essence, a male is born; if essence arrives first and envelops the blood, a female is born. If Yin and Yang arrive equally, a non-male, non-female body is formed. If essence and blood scatter and divide, it indicates twins or multiple fetuses. The *Daozang* (Daoist Canon) states: Conception on the 1st, 3rd, or 5th day after menstruation ends results in a male; on the 2nd, 4th, or 6th day, a female. Li Dongyuan stated: Conception within 1-2 days after the Blood Sea (uterus) is clean results in a male; on days 3-5, a female. The *Shengji Jing* (Holy Relief Classic) states: If Qi moves to the left, Yang nourishes it to form a male; if Qi moves to the right, Yin nourishes it to form a female. Zhu Danxi rejected Chu's view and supported Li Dongyuan's, basing his argument on the *Shengji Jing*'s theory of left and right, attributing it to the ligaments of the left and right uterus. His explanation was considered thorough. I privately believe Chu's view cannot be entirely dismissed, nor is Li Dongyuan's entirely correct. Chu spoke of the sequence of essence and blood; the *Daozang* spoke of odd and even days; Li Dongyuan spoke of the waxing and waning of women's blood; the *Shengji Jing* and Danxi spoke of the left and right of the uterus. Each held a partial truth; integrating them reveals the complete principle. Can single-gender fetuses be determined by days, but can twins/multiples also be determined by days? Historical records show single births of three or four children, sometimes mixed gender, some male-heavy, some female-heavy. Does the "1,3,5 for male, 2,4,6 for female" rule hold true? Is there any logic that a male is conceived on one day and a female on the next? Therefore, the theories of Chu, the *Shengji Jing*, and Danxi regarding essence/blood and uterine left/right are insightful, while those of the *Daozang* and Li Dongyuan regarding days are questionable. Wang Shuhe's *Mai Jing* (Pulse Classic) distinguishes genders of irregular births by the floating/sinking of pulses on the left/right; Gao Yang's *Mai Jue* (Pulse Manual) distinguishes twin shapes by pulse direction and smoothness/obstruction. These are likely speculative and not definitive conclusions.
Shenzhai commented: The above seven passages present differing theories on determining fetal sex during conception. The Classics state: "Left and Right are the pathways of Yin and Yang." "Male and Female are the images of Yin and Yang." Thus, when Yin and Yang harmonize, all things are born; when husband and wife unite, male and female forms arise. It is evident that the birth of males and females is rooted in the principles of Yin and Yang. Therefore, Chu Cheng distinguished sexes by the sequence of essence and blood, Li Dongyuan by odd/even days, and Cheng Mingqian by the simultaneous arrival of the hundred vessels. All these views are imperfect. Hence, Danxi criticized Chu and Li as incomplete, relying instead on the *I Ching*'s concept of Qianyuan initiating life and Kunyuan nurturing life. Lou Quanshan praised this as reaching the pinnacle of subtlety and revealing what predecessors had not. The idea that the uterus divides into left and right to determine sex is flawed. The uterus is the Gate of Life (Mingmen); in women, the Bao Luo (womb) resembles a closed bowl. It does not split into two; claiming left/right division implies two uteri, which is baseless speculation. The *Shengji Jing* discussed Yin/Yang Qi moving left/right to determine sex, not anatomical left/right uteri. Moreover, during intercourse, both parties contribute essence; where is the blood? Chu, Li, and Danxi conflated essence and blood. Have you ever seen male-female union involving only female blood? Previous experts' theories contain many errors; I venture to clarify them.