褚侍中曰∶女人天癸既至，逾十年无男子合，则不调。未逾十年，思男子合，亦不调。不调则旧血不出，新
血误行。或渍而入骨，或变而为肿，或虽合而难子，合多则沥枯虚人，产乳众则血枯杀人。观其精血，思过半矣。
王子亨曰∶经者，常候也。谓候其一身之阴阳愆伏，知其安危，故每月一至。太过不及，皆为不调。阳太过
则先期而至，阴不及则后时而来。其有乍多乍少，断绝不行，崩漏不止，皆由阴阳盛衰所致。
许叔微曰∶妇人病，多是月经乍多乍少，或前或后，时发疼痛。医者一例呼为经病，不辨阴胜阳，阳胜阴，
所以服药少效。盖阴气乘阳，则胞寒气冷，血不营运，经所谓天寒地冻，水凝成冰，故令乍少而在月后。若阳
气乘阴，则血流散溢，经所谓天暑地热，经水沸腾，故令乍多而在月前。当别其阴阳，调其血气，使不相乖，
以平为期也。
陈良甫曰∶妇人月水不调，由风冷乘虚，客于胞中，伤冲任之脉，以损手太阳、手少阴之经也。盖冲任之
脉，起于胞中，人将息顺理，则血气调和，六淫不能为害。若劳伤血气，则风冷乘之，脾胃一伤，饮食渐少，
荣卫日衰，肌肤黄瘦，皆由冲任劳损。故凡遇经行，最宜谨慎，否则与产后证相类。
王子亨曰∶妇人月水不调者，由劳伤气血，致体虚，风冷之气乘之也。冲任之脉，皆起于胞内，为经络之
海。手太阳小肠、手少阴心二经为表里，主上为乳汁，下为月水。若冷热调和，则冲任气盛，太阳少阴所生之
血宣流，根据时而下。若寒温乖适，经脉则虚，如有风冷，虚则乘之，邪抟于血，或寒或温，寒则血结，温则血
消，故月水乍多乍少，为不调也。
褚侍中说：女子天癸（指月经）来潮后，如果超过十年没有与男子交合，就会导致月经不调。如果未满十年，但思念男子而欲交合却不得，也会导致月经不调。月经一旦不调，就会造成旧血排不出，新血妄行。这些血液有的渗入骨骼，有的变为肿胀；即使有男子交合也难以受孕；若交合过多，会导致精血枯竭、身体虚弱；若生育哺乳次数过多，则会导致血枯而死。观察精血的盈亏变化，就明白了大半道理。
王子亨说：月经，是常有的生理征候。它是用来候察全身阴阳之气是否有偏差伏匿的，从而知道身体的安危状况，所以每月来潮一次。经量或经期太过或不及，都属于不调。阳气太过，则月经先期而至；阴气不足，则月经后期而来。如果出现经量忽多忽少、断绝不行、崩漏不止等情况，都是由阴阳盛衰所导致的。
许叔微说：妇女的疾病，大多是月经忽多忽少，或提前或推后，时常发作疼痛。医生们一律称之为“经病”，却不辨别是阴胜阳还是阳胜阴，所以服药很少见效。如果是阴气乘袭阳气，则胞宫寒冷，血液运行不畅，正如《内经》所说“天寒地冻，水凝成冰”，所以导致经量忽少且经期推后。如果是阳气乘袭阴气，则血液流散溢泄，正如《内经》所说“天暑地热，经水沸腾”，所以导致经量忽多且经期提前。应当辨别阴阳的偏胜情况，调和气血，使二者不相乖逆，以恢复平衡为治疗目的。
陈良甫说：妇女月经不调，是由于风冷之邪乘虚侵入，客居于胞宫，损伤了冲脉和任脉，进而损害手太阳小肠经和手少阴心经。因为冲脉和任脉都起于胞中，人体保养得法、顺应理则，则气血调和，六淫（风、寒、暑、湿、燥、火）不能为害。如果劳倦内伤导致气血亏损，则风冷之邪便会乘虚而入，脾胃受损，饮食逐渐减少，营卫之气日渐衰弱，肌肤发黄消瘦，这都是由于冲任二脉劳损所致。所以每逢经期，最宜谨慎调养，否则病情会与产后病症相似。
王子亨说：妇女月经不调，是由于劳倦损伤气血，导致体质虚弱，风冷之气乘虚侵袭。冲脉和任脉都起于胞内，被称为经络之海。手太阳小肠经和手少阴心经互为表里，主管上部化为乳汁，下部化为月经。如果冷热调和，则冲任之气旺盛，由太阳、少阴二经所化生的血液能够按时下注。如果寒温失调，经脉则虚弱，若有风冷之邪，便会乘虚而入，邪气搏结于血中，若是寒气则血液凝结，若是温气则血液消散，所以月经忽多忽少，这就是不调。
Chuzheng (Attendant Chu) stated: Once a woman's Tian Gui (menstrual essence/menses) has arrived, if she does not cohabit with a man for over ten years, her menses will become irregular. If less than ten years have passed, but she desires cohabitation with a man and thus experiences frustration or unfulfilled desire, her menses will also become irregular. When menses are irregular, old blood fails to discharge, and new blood flows erratically. This blood may either seep into the bones or transform into swelling. Even if cohabitation occurs, conception becomes difficult; excessive cohabitation leads to the depletion of essence and blood, causing debility in the person; frequent childbirth and lactation lead to blood exhaustion, which can be fatal. By observing the state of essence and blood, one understands the matter half-way.
Wang Ziheng stated: Menses are a regular physiological indicator. They serve to monitor whether the Yin and Yang of the entire body are deviating or stagnating, thereby indicating health or danger; hence, they occur monthly. Excess or deficiency in volume or timing constitutes irregularity. If Yang is in excess, menses arrive early; if Yin is deficient, menses arrive late. Cases where the flow varies significantly, stops completely, or involves metrorrhagia and metrostaxis are all caused by the fluctuation of Yin and Yang prosperity and decline.
Xu Shuwei stated: Women's diseases often manifest as irregular menstrual volume (either excessive or scanty), irregular timing (early or late), and intermittent pain. Physicians generally label these as "menstrual disorders" without distinguishing between Yin prevailing over Yang or Yang prevailing over Yin; consequently, medication yields little effect. If Yin Qi attacks Yang, the uterus becomes cold, and blood circulation is impaired. As the Classics state, "When heaven is cold and earth frozen, water congeals into ice," leading to scanty flow and delayed menstruation. If Yang Qi attacks Yin, blood flows and spills excessively. As the Classics state, "When heaven is hot and earth warm, menstrual water boils," leading to excessive flow and early menstruation. One must differentiate Yin and Yang imbalances, regulate Qi and Blood, ensure harmony between them, and aim for equilibrium.
Chen Liangfu stated: Irregular menstruation in women results from Wind-Cold pathogens invading due to deficiency, lodging in the uterus, damaging the Chong Mai (Penetrating Vessel) and Ren Mai (Conception Vessel), and subsequently impairing the Hand-Taiyang Small Intestine Meridian and Hand-Shaoyin Heart Meridian. The Chong and Ren Mai originate in the uterus. If the body is nurtured properly and follows natural laws, Qi and Blood remain harmonious, and the Six Evils (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) cannot cause harm. However, if labor and fatigue injure Qi and Blood, Wind-Cold invades. Spleen and Stomach function is damaged, food intake gradually decreases, and Ying (Nutritive) and Wei (Defensive) Qi decline daily. Yellowish complexion and emaciation result from the damage to the Chong and Ren Mai. Therefore, utmost caution is required during menstruation; otherwise, the condition resembles postpartum syndromes.
Wang Ziheng stated: Irregular menstruation in women is caused by labor and fatigue injuring Qi and Blood, leading to physical weakness, allowing Wind-Cold Qi to invade. The Chong and Ren Mai both originate within the uterus and are regarded as the Sea of Meridians. The Hand-Taiyang Small Intestine Meridian and Hand-Shaoyin Heart Meridian are exterior-interior pairs; they govern the transformation of blood into milk above and menses below. If Cold and Heat are balanced, the Qi of Chong and Ren is vigorous, and blood generated by the Taiyang and Shaoyin meridians flows freely according to schedule. If Cold and Heat are mismatched, the meridians become weak. If Wind-Cold is present, it exploits this weakness. Pathogenic factors contend with blood: Cold causes blood coagulation, while Warmth causes blood dissolution. Thus, menses vary in volume, constituting irregularity.