4.月经三旬时一下, 两月并月三居经, 一年一至为避年, 一生不至
孕暗经.
【注】女子阴类也, 以血为主. 其血上应太阴, 下应海潮, 月有盈亏
,潮有朝夕, 月经三旬一下与之相符, 故又谓之月水, 月信也. 女子
月经一月一行者, 其常也. 或先, 或后, 乃其病也. 然亦有两月一行
谓之并月者; 有三月一行, 谓之居经者; 有一年一行, 谓之避年者;
有一生不行而依然能孕育, 谓之暗经者. 此所禀之不同, 而亦非病,
不须治也.
5.经期吐血或衄血, 上溢妄行曰逆经, 受孕行经曰垢胎, 受孕下血
漏胎名.
【注】妇女月经一月一下, 此其常也. 若经行而吐血, 衄血, 下溢妄
行者, 是谓逆经. 有受孕之后, 月月行经而产子者, 是谓垢胎. 有受
孕数月, 其血忽下而胎不陨者, 是谓漏胎. 此皆月经之异乎常者也.
6.天地温和经水安, 寒凝热沸风荡然, 邪入胞中任冲损, 妇人经病
本同参.
【注】经曰: 天地温和, 则经水安静. 天寒地冻, 则经水凝泣. 天暑
地热, 则经水沸溢. 卒风暴起, 则经水波涌而陇起. 六淫之邪入于胞
中,则损伤冲任, 故妇人经病本此同参也. 如寒则血凝, 热则血沸,
风则血荡然波涌而大下, 亦犹经水之被寒, 热, 风而不得安澜也.
4. 月经每三十天来潮一次，这是正常的；如果两个月来潮一次，称为“并月”；如果一年才来潮一次，称为“避年”；如果一生都不来月经但依然能怀孕，称为“暗经”。
【注】女子属阴类，以血为主要基础。其血液上行应合太阴（肺主气、朝百脉），下行应合海潮，月亮有盈亏变化，潮汐有早晚涨落，月经每三十天来潮一次与这些自然规律相符，所以又叫做“月水”或“月信”。女子月经每月来潮一次的，是正常情况。或者提前，或者推后，就是病态了。然而也有两个月来潮一次，称为“并月”的；有三个月来潮一次，称为“居经”的；有一年来潮一次，称为“避年”的；有一生不来月经而依然能够孕育胎儿，称为“暗经”的。这些都是由于先天禀赋不同所致，也并不是疾病，不需要治疗。
5. 经期出现吐血或鼻出血，向上溢出妄行称为“逆经”；受孕后仍有月经来潮称为“垢胎”；受孕后下血但胎儿未堕称为“漏胎”。
【注】妇女月经每月来潮一次，这是正常情况。如果在行经期间出现吐血、鼻出血，血液向下溢出且妄行不止的，这叫做“逆经”。有在受孕之后，每个月仍然来月经并能生育子女的，这叫做“垢胎”。有在受孕数月后，突然下血但胎儿没有流产的，这叫做“漏胎”。这些都属于月经异于常理的情况。
6. 天地气候温和，经水就安宁；寒邪凝滞则经水凝结，热邪炽盛则经水沸腾，风邪扰动则经水动荡不安；邪气侵入胞宫损伤冲脉和任脉，妇人月经病的根本原因与此相同。
【注】医经说：天地气候温和，那么经水就安静平和。天气寒冷大地冻结，那么经水就会凝涩不畅。天气暑热大地燥热，那么经水就会沸腾溢流。忽然狂风大作，那么经水就会波涛汹涌、隆起波动。六淫（风、寒、暑、湿、燥、火）邪气侵入胞宫，就会损伤冲脉和任脉，所以妇人的月经病根本原因都与此相通。比如寒邪导致血液凝滞，热邪导致血液沸腾，风邪导致血液动荡如波涛汹涌而大量出血，也就像经水遭受寒、热、风的影响而不能平静一样。
4. Menstruation occurring every thirty days is normal; menstruation occurring once every two months is termed "Bingyue" (Combined Month); menstruation occurring once a year is termed "Bi Nian" (Avoiding Year); and the condition where menstruation never occurs throughout life yet pregnancy is still possible is termed "An Jing" (Hidden Menses).
【Note】Women belong to the Yin category, with blood as their primary substance. Their blood corresponds upward to the Taiyin (Lung meridian governing Qi and connecting to all vessels) and downward to the ocean tides. The moon has waxing and waning phases, and tides have morning and evening fluctuations. Menstruation occurring every thirty days aligns with these natural rhythms, hence it is also called "Yue Shui" (Monthly Water) or "Yue Xin" (Monthly Trust). For women, menstruation occurring once a month is the norm. If it arrives early or late, it indicates pathology. However, there are cases of menstruation occurring once every two months, termed "Bingyue"; once every three months, termed "Ju Jing" (Residing Menses); once a year, termed "Bi Nian"; and cases where menstruation never occurs throughout life yet conception remains possible, termed "An Jing". These variations arise from differences in innate constitution and are not diseases, requiring no treatment.
5. Hematemesis or epistaxis during menstruation, characterized by upward overflow and reckless flow, is termed "Ni Jing" (Rebellious Menses); menstruation continuing after conception is termed "Gou Tai" (Stained Fetus); bleeding after conception without fetal expulsion is termed "Lou Tai" (Leaking Fetus).
【Note】For women, menstruation occurring once a month is the norm. If hematemesis or epistaxis occurs during the menstrual period, with blood flowing recklessly downwards or upwards, this is called "Ni Jing". There are cases where, after conception, menstruation continues monthly until childbirth, termed "Gou Tai". There are cases where, several months after conception, sudden bleeding occurs but the fetus is not miscarried, termed "Lou Tai". All these represent deviations from normal menstruation.
6. When heaven and earth are mild and warm, the menses remain tranquil; cold causes coagulation, heat causes boiling, and wind causes turbulence; when pathogenic factors enter the uterus damaging the Chong and Ren meridians, the root cause of women's menstrual disorders is consistent with this principle.
【Note】The medical classics state: When heaven and earth are mild and warm, the menses remain tranquil. When the weather is cold and the earth frozen, the menses become stagnant and sluggish. When the weather is hot and the earth dry, the menses boil and overflow. When sudden storms arise, the menses surge like waves and rise up. When the Six Excesses (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) pathogenic factors enter the uterus, they damage the Chong and Ren meridians; thus, the fundamental basis for women's menstrual disorders lies in this same principle. For instance, cold causes blood coagulation, heat causes blood boiling, and wind causes blood turbulence resembling surging waves leading to massive hemorrhage, just as menses fail to remain calm when subjected to cold, heat, or wind influences.