Hematochezia during menstruation refers to the occurrence of bloody stools in women during or before their menstrual period, which resolves after the period ends and occurs cyclically. Other instances of bloody stools unrelated to the menstruation cycle are not within the scope of this discussion.

The "Bamboo Grove Gynaecology" mentions a condition called "cha jing," which refers to the phenomenon where blood is discharged from both the stool and urine during menstruation; the "Bamboo Grove Gynaecology Secret Prescriptions" also mentions a condition called "cuo jing," referring to vicarious menstruation and bloody stools during menstruation; the "Secretly Transmitted Inner Palace Experienced Gynaecology" calls it "zhong jing"; "Yang Er Bao" calls it "cuo jing"; "Gynecology Guide" calls it "cuo li syndrome"; Gynaecology references call it "cuo chan"; "Essentials of Women's Health" also refers to "cha jing" as "recto-urethral fistula."

This discussion is limited to the cyclical occurrence of bloody stools in women before or during their menstrual period. Other conditions such as bloody stools related to internal medicine or anal diseases are discussed separately.

bubble_chart Pattern Analysis

1. Stomach and Intestine Stagnant Heat︰Bleeding during defecation before or during menstruation, with dark red or bright red blood. Or flushed face, dry lips, dry throat, bitter taste in mouth. Scanty menstrual flow, purplish-red in color, thick and sticky in texture, or even amenorrhea. Dry stools, yellow urine, red tongue with yellow coating, slippery and rapid pulse. The syndrome belongs to excess heat, mostly caused by excessive consumption of spicy, fried, and dry foods that stir up fire, leading to heat stagnation in the Yangming and injury to the intestinal collaterals, resulting in bloody stool. The Chong channel is the Sea of Blood and is subordinate to the Yangming. When menstruation is about to begin, the qi and blood in the uterus are both abundant, thus stirring up latent heat in the intestines and forcing blood downward, hence bloody stool often occurs one or two days before menstruation; blood is scorched by heat, hence both bloody stool and menstrual blood appear purplish-red and sticky; blood is lost through the anus, hence scanty menstrual flow or even cessation; internal exuberance of stagnant heat in the Yangming leads to flushed face, dry mouth, dry stools, yellow urine, red tongue with yellow coating, and slippery, rapid pulse as accompanying symptoms. Treatment should focus on clearing heat and cooling blood, regulating menstruation, and stopping bleeding, using Yueying Decoction.
2. Spleen Failing to Control Blood︰Menstrual bloody stools with dull-colored blood, limb fatigue, mental fatigue, shortage of qi, reluctance to speak, complexion without luster, palpitation, insomnia, or poor appetite, loose stools, and cold limbs. Menstruation comes early with heavy flow and dull-colored blood. The tongue is pale white or with tooth marks, and the pulse is thin, slow, and weak. It belongs to the pattern of deficiency cold. Mostly caused by prolonged bloody stools, leading to damage of middle qi. It can also result from factors such as dietary overstrain, seven emotions causing internal damage, and injury to middle qi. Qi is the commander of blood; qi deficiency leads to inability to control blood circulation. When menstruation occurs, qi is lost along with blood, and the qi of the stomach and intestines becomes even more deficient, causing the loss of yin blood and resulting in bloody stools. Therefore, this condition often occurs after the onset of menstruation, with dull-colored and heavy bleeding. It is also accompanied by limb fatigue, mental fatigue, palpitation, shortage of qi, poor appetite, loose stools, a pale tongue, and weak pulse—symptoms of spleen deficiency and qi weakness. Treatment should focus on tonifying qi and controlling blood, using Returning to Spleen Decoction or Oven Yellow Earth Decoction.

bubble_chart Documentation

1. Fuqingzhu Gynecology．Regulating Menstruation: "There are women who experience bleeding from the large intestine the day before their menstrual period. People think it is a symptom of menorrhagia, but who would have thought that the menstrual flow is actually going to the large intestine! The large intestine and the path of menstruation are distinct, so how can the menstrual blood enter the large intestine? It is not known that the connection of the uterus extends upward to the heart and downward to the kidneys. If there is non-interaction between the heart and kidney, the blood of the uterus has nowhere to go, and the qi of the heart and kidney meridians does not come to regulate it, allowing it to flow freely. This is why the blood does not go to the small intestine but to the large intestine. ... It is essential to greatly tonify the heart and kidneys, so that the yin qi and yang qi of the heart and kidney meet together, and the qi of the uterus naturally does not disperse. Then the blood in the large intestine will not flow recklessly, and the menstrual flow will naturally become regular."