Progress in Chinese and Western medicine research on the pathogenesis of constipation in women Xiyuan Hospital, Chinese Academy of Traditional Chinese Medicine, 100091 Jia Xiaoqiang Xu Chunyan Cheng Fang Xie Zhennian Cao Weiwei Jia Xiaoqiang, Department of Anorectal Medicine, Xiyuan Hospital, Chinese Academy of Traditional Chinese Medicine Constipation is a condition in which feces are retained in the intestine for too long and become constipated, with prolonged bowel cycles, or cycles that are not long, but the feces are dry and difficult to pass, or the feces are not hard, and although there is an intention to pass stool, the stool is not smooth[1] . . According to statistics, the overall prevalence of constipation in the world is 0.7 % – 79.0 %, with an average of 16.0 %[2] , and the total prevalence of constipation in China is 9.18 %[3] , and female patients with constipation are more common in clinical practice, with women being more than four times as common as men[4] . In addition to systemic factors, the causes are closely related to the anatomical, physiological and psychological factors specific to women. Therefore, it is important to study the causative factors and characteristics of female constipation to effectively prevent and treat female constipation.1 The causes of constipation in women are complex and diverse, and there are abundant records on the causes of constipation in medical books throughout the ages. The “re-revised Yan’s Jisheng formula – secret conclusion treatment” said: “five secret, wind secret, gas secret, wet secret, cold secret, heat secret is also. What’s more, sweat and urine, and women’s newborn blood, go depletion of fluid, often are constipated.” In summary, the cause of constipation is summarized in two aspects of external sensations and internal injuries. In terms of the relevant internal organs, the basic pathology of constipation belongs to the large intestine conduction disorder, and is related to the dysfunction of the lung, spleen, stomach, liver, kidney and other internal organs. Constipation clinical sub-certification is more complex, now on the female constipation high incidence of etiology is summarized as follows.1.1 liver loss of drainage The location of constipation is in the large intestine, but closely related to the function of the liver main drainage, in women is more obvious performance, Ye Tianshi had in the “clinical evidence guide medical case” proposed “women to liver for the first”, “liver The liver is the organ of wind and wood, so it is the general’s official. Therefore, the liver disease, more than other organs, and in women especially.” The liver is the master of drainage, which means that liver qi has the function of unblocking and unobstructing the qi of the whole body, thus promoting the flow and distribution of essence, blood and fluid, the rise and fall of the qi of the spleen and stomach, the secretion and excretion of bile and the relaxation of the emotions. If depression or anger affects the discharge of the liver, all diseases will arise. As stated in “Suwen – The Treatise on Pain”, “All diseases are born from Qi”. Women need to face family, work, social pressure, plus menstruation, physiological cycle, pregnancy and childbirth, menopause and other special periods of physiological changes in the body, mood fluctuations than men, sadness and depression, emotional and mental depression, or due to sedentary less active, lying down for a long time to hurt the qi, and due to the acquired fall, abdominal surgery, etc. resulting in intestinal injury or adhesion, or phlegm, dampness, silt and blood blocking the intestinal complex, can lead to intestinal qi obstruction, stagnation, stagnation. The constipation can be caused by obstruction of intestinal qi, stagnation, and decrease in the function of the large intestine to transfer the dregs. In addition, if the disease further develops, because the liver body Yin and Yang, if the liver Qi stagnation is too much, can form blood stasis, further blocking the intestinal complex, aggravate the bowel irregularities; or Qi depression for a long time into fire, forcing blood delusion and see blood in the stool; fire heat further injury Jin and depletion of Qi, Qi depletion is very weak after the stool, Jin injury is very no water boat stop, see dry stool like sheep dung ball. Some recent investigations have also shown that anxiety and depression scores in the psychological test results of people with defecation disorders are significantly higher than those of normal controls [6], which shows that patients with functional constipation may have some psychological disorders such as anxiety and depression to different degrees, and such mental factors in turn affect the coordination of rectal and anal canal movements during defecation and aggravate constipation [7] [8]. 1.2 Qi and Yin depletion As stated in “The Complete Good Formula for Women The special physiological stages of women, such as menstruation, belt, fetus, childbirth and breast milk, are all directly related to blood and fluid. The “Spiritual Pivot – Five Sounds and Five Flavors” says: “Nowadays, women’s births are surplus to Qi and deficient to Blood, because their numbers are also off Blood.” It points out that female diseases are mostly due to surplus of qi and deficiency of blood. In adolescence, a lot of menstrual blood is lost due to menorrhagia, excessive menstruation, prolonged intermenstrual period and other menstrual diseases; during childbirth, pregnancy and delivery, abortion and miscarriage, nursing a fetus, excessive childbirth, pelvic surgery, etc., too much blood is removed and fluid is dried up, resulting in dryness of the intestines and stomach due to blood deficiency and fluid deficiency, however, blood can carry qi, too much blood loss can lead to qi shedding with blood, which eventually becomes a deficiency of both qi and yin. 1.3 Yin cold condensation, stasis of blood Women due to childbirth trauma, damage to the veins, blood overflowing outside the veins; postpartum vacancy, carelessness, feeling cold, cold stagnation, Qi, blood and fluid condensation; or uterine clothing, placenta residue; menstrual cold can be when the blood does not return to the meridian, generating stagnant blood, clotting in the large intestine. This causes intestinal obstruction and difficulty in defecation, as stated in the Jin Kui Yi: “Cold constipation, cold gas, accumulation in the intestines and stomach, condensation of yin and solidification, Yang Qi does not work, fluid does not work.” 1.4 Qi sink Women with weak body and insufficient middle qi, if they have too many children; childbirth injury; too much blood loss during childbirth, qi is depleted with the blood; after menstruation and childbirth, they do not take in the tonic, heavy exertion, depletion of qi and injury, resulting in the depletion of middle qi, qi deficiency and sinking, unable to lift, resulting in pelvic organs sagging, intestinal mucosa stacking, blocking the intestinal cavity, plus the spleen is the main muscle, middle qi sink, resulting in muscle relaxation, transmission is weak, so see Although the effort to struggle and feces can not come out. However, in different stages of constipation, the above-mentioned types of evidence can be transformed into each other, or the patient has two or more conditions at the same time, the clinical evidence needs to be identified, timely adjustment of prescriptions and medicine. 2 Western medical etiology of female constipation Domestic research studies on patients with chronic constipation show that the proportion of each type of constipation: outlet obstruction type constipation (OOC), slow transmission type constipation (STC) and mixed type constipation (MC) 50.8%, 10.2% and 39.0%, respectively [9], while women were affected by various physiological factors. 2.1 Female anatomical features and constipation In men, the anterior rectal wall is adjacent to the urethra and prostate. Its support is strong, and anterior rectal protrusion rarely occurs [10]. Women have a wide pelvis, small perineal body, weak muscles and fascia of the urogenital triangle, less support in front of the anus, thin vaginal-rectal septum, the front wall of the rectum is flaccid and easy to expand to the vagina, forming a rectal protrusion, fecal mass under pressure when defecating into the rectal protrusion and can not be discharged from the anus. After stopping the pressure, the fecal mass is “bounced” back into the rectum, resulting in a sense of incomplete defecation, forcing the patient to make more forceful defecation movements, resulting in a gradual deepening of the protrusion and increasing constipation [10]. In women, the anal canal is short, the rectum is flaccid during defecation, the rectal wall is squeezed between the elevated abdominal pressure and the contracted pelvic floor, and the anterior wall is prone to prolapse; the rectal mucosa prolapses, resulting in difficulty in emptying the rectum, resulting in incomplete defecation and anal obstruction. And the greater the force, the heavier the obstruction. The patient is prompted to insert fingers or suppositories into the anus to assist in defecation. Secondly, the Douglas fossa is deeper in women than in men, and the intestinal tube in the abdominal cavity sags and compresses the pelvic floor and rectum, which affects fecal transmission and emptying and leads to constipation [11]. In addition, in women, the uterus is adjacent to the rectal wall, and due to injuries in childbirth, multiple births, and premature physical labor after delivery, the supporting tissues of the uterus are relaxed, resulting in the uterus shifting backward or prolapsing, compressing the anterior rectal wall, narrowing and bending the rectal cavity, preventing fecal evacuation, which can cause constipation in women.2.2 Pregnancy and constipation After pregnancy, the weight of the uterus gradually increases, especially above the sixth month of pregnancy. The enlarged uterus compresses the intestinal canal, causing obstruction to the movement of intestinal contents; the increased intra-abdominal pressure during pregnancy compresses the pelvic cavity, the pelvic venous reflux is poor, the rectal mucosa is chronically stagnant, weakening the tension of the intestinal mucosa, making it loose and sagging, and because of the reduced secretion of gastric acid during pregnancy, both of which can inhibit rectal peristalsis, prolonging the time that stool stays in the intestinal cavity, increasing water absorption, resulting in dry, hard stool and difficult discharge. In addition, the tension of the levator muscle plate, which supports the pelvic organs, is weakened by the hormonal influence of pregnancy, and relaxes and sinks, so that the levator muscle fissure is enlarged, and due to the change in the position and volume of the uterus, the direction of the pressure on the pelvic floor changes to act directly on the enlarged levator muscle fissure area [12], and the above factors form the conditions of pelvic floor organ prolapse or bulge. Prolapsed or bulging pelvic floor organs, such as perineal descent, endorectal stenosis, rectal bulge, and pelvic floor hernia, can lead to decreased bowel function and constipation.2.3 Childbirth and constipation Childbirth is the most basic and common cause of anterior rectal protrusion constipation. The anterior midline crossed fibers of the levator ani and puborectalis muscles are torn during delivery, which can damage the strength of the rectovaginal septum and dilate the weak rectovaginal septum. The onset of the disease is usually postpartum, suggesting that it is associated with transvaginal delivery [14]. In addition, childbirth can cause injury to the pubic nerves that innervate the transverse pelvic floor muscles. During pregnancy and delivery, the abdominal pressure increases, the pelvic floor drops, and the nerve strains are damaged. A normal nerve is susceptible to injury when the pulling force is greater than 12% of its length. During delivery, the pelvic floor can drop by 50 px [12], and when the pelvic floor drops >20 mm, the pudendal nerve is elongated by 20%, which is more than 12% of the reversible injury. The excessive elongation of the nerve slows down the rate of excitation conduction and results in denervation of the pelvic floor muscles, which may lead to motility disorders such as insufficiency of the levator muscle, hypertrophy or spasm of the puborectalis muscle, and paradoxical contraction of the external sphincter, resulting in obstruction of the defecation passage and constipation. Large weight babies, prolonged second stage of labor, use of forceps, and multiple births are all high-risk factors for these injuries. In most first-time mothers, the damage can be recovered quickly, but in those who have had multiple deliveries, the repeated damage cannot be recovered, resulting in difficulty in defecation and straining to defecate, and repeated perineal descent strains and damages the nerves in the pubic area, resulting in a vicious cycle, which eventually leads to chronic constipation. 2.4 Estrogen levels and constipation Female hormone abnormalities may be related to constipation. The secretion of progesterone during the female physiological cycle can inhibit intestinal peristalsis and reduce the sensitivity of intestinal stimulus receptors, leading to constipation. Tong Weidong et al [15] examined 29 female patients with constipation, and sex hormone abnormalities accounted for 61 %. It was shown that overexpression of progesterone receptors in patients with slow-transmission constipation could regulate contractile G-proteins and upregulate inhibitory G-proteins ultimately leading to colonic motility disorders [16].2.5 Gynecological diseases and constipation Qunbo Zhang [17] found that more than 80% of female patients with rectal prolapse had gynecological diseases, especially cervicitis, cervical hypertrophy and retroversion of the uterus, due to internal It is often caused by inflammation of the genitalia, childbirth, injury, poor recovery of the pelvic floor and other uterine supporting tissues after childbirth. According to statistics, more than 41% of female patients with rectal prolapse have a history of pelvic surgery [18], e.g., loss of support of the anterior rectal wall after hysterectomy, which predisposes to mucosal prolapse and rectal prolapse [10]. Patients with female outlet obstruction constipation often have a combination of bladder prolapse or bulge, retroversion of the uterus, and a range of urologic and gynecologic symptoms, such as urinary frequency, stress urinary incontinence, difficulty urinating, perineal cramping, increased and yellowish leucorrhea, and painful intercourse [19]. When lesions cause the uterine body and cervix to increase in size, weight, and tilt backward, pressing the lower part of the anterior rectal wall, narrowing or bending the rectal cavity, patients experience lower abdomen and anus, lumbosacral swelling, difficulty in defecation, and blockage during defecation; when suffering from gynecological diseases such as cervicitis and cervical hypertrophy, the normal orbit of intestinal feces changes and pressure increases, resulting in increased friction with the mucosa of the intestinal cavity, which can This can cause prolapse of the rectal mucosa, which over time can lead to a decrease in the elastic retraction of the submucosal tissue fibers, hypertrophy and degeneration of the supporting and connecting fibers, followed by fracture, and the formation of endoplasia. The pelvic inflammatory disease, hypertrophy of the cervix, degenerative changes in old age and other factors can further cause damage to the pelvic floor and other uterine support tissues, hypertrophy and degeneration of muscle fibers, poor elasticity, relaxation of the pelvic floor muscle groups, perineal decline, and disruption of the balance of forces on the lower part of the anterior rectal wall, under the action of pathological factors such as mucosal prolapse, overlap, protrusion of the rectum, posterior pressure of the uterus, and perineal decline, when gravity, abdominal pressure and fecal friction are greater than When gravity, abdominal pressure and fecal friction are greater than the elastic retraction force of the muscle tissue of the intestinal wall and the support force of the tissue below, it will easily lead to exit obstruction and constipation. Patients try to empty by increasing the abdominal pressure, but the obstruction is aggravated, making the rectal protrusion more obvious, the mucosal prolapse is aggravated, and the symptoms are heavier, forming a vicious circle. Therefore, gynecological diseases such as cervicitis, cervical hypertrophy, posterior uterus, and birth injury are the initiating and determining factors of rectal outlet obstruction constipation in women [20]. Under normal conditions, the peritoneum in the female pelvis folds back from the bladder to the uterus and then to the anterior wall of the rectum, forming a recto-uterine depression between the uterus and the rectum, which can deepen and form a hernia sac if the tissue around the rectum is lax. During defecation, the sigmoid colon herniates into it and compresses the rectum, resulting in a series of discharge obstruction and downward symptoms. Liu Sifang et al [21] found that the prevalence of chronic constipation in women with pelvic organ prolapse (including uterine prolapse, anterior vaginal wall prolapse, and posterior vaginal wall prolapse) was 28.7% using a questionnaire survey; endometriosis is a comorbidity of various gynecological surgeries and is a common disease in women after marriage and childbirth. The ectopic site is mostly in the rectal uterine recess, forming a solid nodule or mass. According to Zhang D.W. [22] Zhang D.W., Meng Fancheng. Diagnosis and differential diagnosis of constipation in women. Chinese Journal of Practical Surgery, 1993, 13(12):714-716.] reported 1,694 cases of endometriosis with constipation accounting for 85.7 %. 2.6 Female psychological factors and constipation Wang Yuming et al [23] found that the sel-rating depression scale (SDS), the self-rating anxiety scale (SAS), and the functional constipation scale (FC) in patients with functional constipation (SDS) were all used in the diagnosis of constipation. Dykes et al. [24] found that FC patients had significantly higher scores on the hospital anxiety and depression scale (HADS) than controls (healthy volunteers or patients’ spouses and children), suggesting a significant tendency for depressive and/or anxiety psychological disorders in FC patients; female FC patients had significantly higher scores on the three groups than males, suggesting a more pronounced tendency for psychological disorders in female FC. [24] found that psychological disorders were particularly prominent in female patients with idiopathic constipation, and Wald et al [25] found that interpersonal, anxiety, terror, paranoia and psychotic factors were significantly higher in patients with normal transmission compared to slow transmission (p < 0105). In general, women's psychology is more susceptible to large fluctuations due to environmental and temporal factors, and chronic anxiety, terror, and depression can inhibit bowel movements and raise the threshold of rectal irritation receptors, leading to constipation [11].Devroede et al [26] reported that the MMPI (Minnesota Multiphasic Personality Inventory) was used as a psychological testing tool for 38 female constipation The results showed that the scores of hypochondriac (HS) and hysteria (HY) were above the upper limit of normal; it was also found that anxiety levels were highly correlated with mean transit time (TT) in patients with prolonged colonic transit time in constipation. Studies have shown [27] that mood swings can cause an overreaction in the vegetative nervous system associated with smooth muscle contraction. In the female population, there is a greater tendency to shy away from bowel problems and ignore "bowel movements" due to environmental and interpersonal changes, and the frequent suppression of bowel movements results in a higher rectal threshold, leading to constipation. The scores of somatic symptoms, depression, and anxiety were significantly higher in patients with chronic constipation compared to normal controls. Psychological disorders may cause constipation by inhibiting the peripheral autonomic innervation of the colon, and also by affecting the hypothalamus and the vegetative nervous system, especially the parasympathetic nerves, through the cerebral cortex [29] Depression is one of the most commonly encountered psychiatric disorders in patients with constipation, and the degree of depression varies from mild (bad mood) to psychotic. 2.7 Women's eating habits and constipation By nature, many women have poor dietary habits of dieting or eating too finely, and anorexia nervosa is more common in women with constipation. As a result of eating too little fiber, it cannot produce effective stimulation of the gastrointestinal tract, the gastrocolonic reflex is weakened and the intestinal pressure is insufficient, then the defecation reflex is also weakened; women are relatively less active, most of them prefer static and evil movement, and weakened intestinal peristalsis can easily induce constipation. 2.8 Overdose of laxatives Under normal circumstances, the nerve receptor cells in the rectal wall are very sensitive to pressure, and when subjected to a certain threshold pressure, the impulses are transmitted via the pelvic nerve and infra-abdominal nerves to the lower centers of the lumbosacral defecation reflex and the higher centers of defecation activity in the thalamus and cerebral cortex to complete defecation [30]. However, there are few modern women who use laxatives frequently for a long time in order to pursue slimming; or patients who are constipated and need to use laxatives to assist defecation, and long-term laxative abuse reduces the stress of intestinal wall cells and increases the response threshold, so that even if there is a sufficient amount of stool in the intestine, the defecation reflex is not produced, resulting in difficulty in defecation and constipation [31]. The vicious circle is caused by the inability to defecate without taking laxatives or enemas. It can also lead to colorectal melanosis. Some animal experiments found that long-term use of irritating laxatives can damage the intestinal nerves [32]. Guilin et al [33] used rhubarb infusion to establish a "laxative bowel" model, and found that rhubarb could cause intestinal chromophores to gradually tolerate laxative stimulation, and the release of 5-HT was relatively reduced, resulting in slowed peristalsis of the gastrointestinal tract and S T C . In conclusion, women are vulnerable to constipation due to their anatomical, physiological and pathological peculiarities. Understanding the causes of female constipation can help us better grasp the characteristics of female constipation and guide clinical management. Female constipation patients are often accompanied by gynecologic or obstetric abnormalities, while anorectal physicians in the diagnosis and treatment of female constipation, it is easy to ignore the impact of gynecologic or obstetric diseases on constipation, resulting in missed diagnosis, misdiagnosis, and subsequent loss of treatment and misdiagnosis. In view of the characteristics of female constipation, we should consider the pelvic organs as an organic whole, analyze the morphological and functional changes of the pelvic floor in female patients with constipation, study their influence on defecation and their interaction, so as to reveal the role of gynecological factors in the occurrence of the disease, in order to further determine whether to operate on female patients with constipation and the type of surgery, and to provide an objective basis for the scope and extent of surgical correction, thus making It also provides an objective basis for the scope and extent of surgical correction, thus making the diagnosis more accurate and objective, and the treatment more reasonable and effective. References