Fecal Incontinence and Diarrhea During Pregnancy

INTRODUCTION AND PHYSIOLOGY Gastrointestinal (GI) symptoms are common during pregnancy, with the most common reports being nausea and vomiting, reflux, and constipation. The topics of diarrhea and fecal incontinence (FI) in pregnancy receive less attention in the GI literature, with diarrhea being less common than constipation in pregnancy and FI being often at the intersection of GI and obstetrics. Although acute infection is the most common cause of diarrhea in pregnancy, noninfectious, noninflammatory diarrhea can also occur during pregnancy because of several factors: hormonal changes, recent uptake of a “healthier diet” with fiber-rich foods or calcium-rich milk products, prenatal multivitamin side effects, or preexisting conditions. Diarrhea can lead to fecal urgency and FI that becomes amplified during pregnancy because of the increased intra-abdominal pressure from the gravid uterus, preexisting pelvic floor dysfunction, and potentially decreased mobility during the last trimester of pregnancy. Previous pregnancy is associated with pelvic floor dysfunction in up to 45% of patients (1), and prior trauma to the posterior pelvic floor, such as a prior obstetrical laceration involving the anal sphincter, can lead to FI in the absence of altered bowel habits. Although cesarean deliveries are associated with less pelvic floor dysfunction and organ prolapse than vaginal deliveries, it seems that the main stress on the pelvic floor comes from the pregnancy itself more than the mode of delivery. Constipation, which is also common during pregnancy and the postpartum period, can lead to overflow diarrhea and FI as well. Patients with prior anorectal surgeries or with ileal pouch anal anastomosis are also at higher risk of FI during pregnancy (2). Whether the diarrhea and/or FI are related to the pregnancy itself or due to new onset or exacerbation of a preexisting disorder, these symptoms negatively affect the physical, emotional, and social health of the pregnant person and need to be properly addressed and managed. EVALUATION Differential diagnosis The differential diagnosis of acute and chronic diarrhea in pregnancy is similar to that in the nonpregnant population. The most common cause of acute diarrhea is infection, typically from a viral pathogen, such as rotaviruses and Norwalk virus. Clostridioides difficile infection is associated with an increased risk of maternal sepsis, paralytic ileus, thromboembolism, and mortality (3). Because of the negative impact of pregnancy-associated listeriosis on the fetus and neonate, a high index of suspicion should be maintained in a pregnant patient presenting with diarrhea and fever or flu-like symptoms. Chronic conditions such as irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), celiac disease, lactose intolerance, and hyperthyroidism can be unmasked or exacerbated during pregnancy. Finally, with the incidence of colorectal cancer increasing in younger individuals, it is important to consider rectal malignancy in a patient presenting with a new change in the bowel habit pattern and FI. Key elements for the evaluation of FI are summarized in Table 1.Table 1.: Summary of workup of diarrhea and fecal incontinence during pregnancyHistory A thorough review of travel history, household or work-related sick contacts, dietary habits (including raw food intake, fiber supplements, milk products, and sugar substitute intake), and new medications including antibiotics should be performed. Acute large volume and watery diarrhea is likely to be due to viral agents, whereas bacterial pathogens produce inflammatory diarrhea with frequent small bowel movement and occasional blood in the stool, abdominal pain, and fever. Foul-smelling diarrhea alternating with soft greasy stool, abdominal cramps, and bloating suggest Giardia infection, the most common intestinal parasitic infection in the United States and the world. Extraintestinal symptoms such as flu-like symptoms, neurological symptoms, IBD, or celiac-associated joint or skin manifestations should be assessed. A history of cholecystectomy or ileocolonic resection suggests bile acid diarrhea while prior bowel surgeries can lead to diarrhea from small bowel bacterial overgrowth. Patients with FI are often reluctant to report their symptoms, and physicians should screen pregnant patients for FI, especially when the main report is diarrhea, and patients at higher risk of FI during pregnancy as described above (4). Once identified, further questioning should determine the onset, frequency, and type of FI (i.e., gas, liquid, staining, and full); association with change in bowel habits; rectal urgency or straining; and blood in the stool. Motor or sensory dysfunction in the lower extremity and coexisting urinary incontinence suggest a neurological disorder such as a spinal cord lesion. A history of anorectal surgery (e.g., hemorrhoidectomy and fissurectomy), ileal pouch anal anastomosis, and prior vaginal deliveries complicated by perineal lacerations or forceps use may suggest the presence of a weakened anal sphincter. Finally, patients who report of tissues protruding from the anal canal may indicate prolapsing hemorrhoids or rectal prolapse. Physical examination In addition to a general physical examination looking for evidence of dehydration or extraintestinal manifestations of infectious or inflammatory disease in patients presenting with diarrhea, a focused examination of the perianal area and digital rectal examination (DRE) should be performed in patients with FI (5). The DRE is generally performed with the patient in the left lateral position and begins with inspection of the perineal area to assess for skin abnormalities, such as irritation from chronic anal leakage, presence of a fistula, prolapsed hemorrhoids, or a prolapsed rectum. On simulated defecation, the perineum normally descends 2–4 cm; a descent of the pelvic floor muscles of more than 4 cm (or beyond the ischial tuberosities) is associated with FI (6). The perineal sensation and anal wink (i.e., reflexive contraction of the external anal sphincter by gently stroking the perianal skin) suggests integrity of the motor and sensory nerves at the levels of S4–S5. The DRE allows for the assessment of the anal sphincter pressure at rest, during squeeze and simulated defecation, as well as the evaluation of anorectal mass and of fecal impaction. Laboratory testing The evaluation of acute diarrhea includes stool studies for bacterial (including C. difficile), parasitic, and viral (norovirus and rotavirus) infections. When listeriosis is suspected, blood culture (and an infectious disease consultation) should be obtained. Checking for inflammatory markers, such as fecal calprotectin or lactoferrin (recognizing that C-reactive protein can be elevated in normal pregnancy), thyroid, and celiac serology should be performed in patients with a history of IBD or other chronic illness associated with diarrhea or who develop chronic diarrhea during pregnancy or diarrhea suggestive of an organic disease. Imaging Flexible sigmoidoscopy (with or without sedation) may be necessary in patients where there is concern for IBD or malignancy. Colonoscopy is relatively safe during pregnancy and can be performed when strongly indicated in the second or third trimester (please refer to endoscopy in the pregnancy chapter in this monograph for more details). Further anal sphincter imaging for FI with endoanal ultrasound or MRI is rarely necessary during pregnancy. Endoanal ultrasound provides superior imaging of the internal anal sphincter while MRI has the advantage of assessing for external anal sphincter abnormalities or the presence of a fistula. MR defecography, which can detect rectal prolapse and assess the anorectal angle, perineum, and pelvic organs during simulated defecation, is rarely necessary for the evaluation of FI during pregnancy. Other testing Anorectal manometry (ARM) can provide important information regarding anal sphincter pressures (resting and squeeze), anorectal inhibitory reflex, rectal sensation during balloon distention, and rectal and anal pressures during simulated defecation (7). When available, 3D high-definition ARM can also assess for pressure symmetry within the sphincter (8). The balloon expulsion test, which is performed on a bedside commode by asking the patient to expel a 50-cc water-filled balloon, is important for the evaluation of dyssynergic defecation, which may be present in patients with fecal impaction and overflow FI. The assessment of the electrophysiological activity of the anal sphincter is most commonly performed by evaluating pudendal nerve latency and less commonly with needle EMG (9). Although ARM testing may be helpful and, in general, well tolerated in pregnancy, they should be limited to those who fail to respond to conservative treatments. TREATMENT AND PHARMACOTHERAPY OF DIARRHEA The treatment of diarrhea in pregnancy varies by diagnosis and should target the underlying organic cause when present. The management of a new diagnosis of IBD or IBD exacerbation is covered in a separate chapter in this monograph. In this review, we will focus on the management of acute diarrhea and chronic functional diarrhea and review the safety of commonly used medications for those conditions during pregnancy and breastfeeding (Table 2).Table 2.: Summary of the safety of medical therapies for infectious and noninfectious diarrhea and fecal incontinence in pregnancy and breastfeedingAcute diarrhea Fluid repletion/Dietary recommendations Most episodes of acute diarrhea are usually self-limited and mild; however, there should be a low threshold to seek care and replenish fluids during pregnancy because of the serious risk of dehydration in this population. Conservative management including oral rehydration and careful monitoring of fetal well-being is essential. Oral rehydration solutions (ORSs) that contain glucose will accelerate absorption in the jejunum; however, an ORS that contains a microbially fermentable starch (termed hypo-osmolar high-amylose maize starch) has been found to be superior (10–12). This type of ORS allows the delivery of a nonabsorbed starch into the colon, which is then fermented into short-chain fatty acids and stimulates colonic sodium and fluid absorption (e.g., CeraLyte 70). If there is prolonged diarrhea, IV hydration with the correction of electrolyte abnormalities may be needed. Dietary modifications with small, frequent meals, which include salty soups, carbohydrates, fruit juices that are low in fat, and caffeine and do not contain artificial sweeteners, are advised (13). Dairy products, except yogurt, should be avoided because the enteritis can cause secondary lactase deficiency, which may last for months after the original insult (14). Pharmacologic treatment Opioids. Loperamide is a peripherally acting opiate-receptor agonist, is the preferred antidiarrheal agent in pregnancy, and should be used for persistent or severe symptoms. Loperamide has been associated with a moderate risk of infant malformations in one registry trial, but in a prospective, controlled multicenter trial, there was no association with infant malformations, except for lower birth weights (15–17). Diphenoxylate with atropine showed adverse events in animal studies and is not recommended during pregnancy (15). Bile acid sequestrants. Bile acid sequestrants, such as colestipol or cholestyramine, can be used to treat bile acid diarrhea and IBS diarrhea (IBS-D). Bile acid sequestrants can interfere with the absorption of fat-soluble vitamins, which could lead to maternal coagulopathy by a low-vitamin-K mechanism (18). Patients who take bile acid sequestrants regularly during pregnancy should be checked for fat-soluble vitamin deficiency and disordered clotting function because regular prenatal supplementation may not be adequate (15,18). Bismuth preparations. Bismuth subsalicylate, found in Pepto-Bismol and Kaopectate, is commonly used in acute diarrhea in the nonpregnant population and reduces the number of unformed stools and symptoms (19). However, fetal toxicity experts recommend against the use of these products during pregnancy, especially in the second and third trimesters, because it is hard to control how much of the subsalicylate is converted to salicylate, which at high dose is associated with fetal adverse effects (15). Probiotics. Probiotics are nonpathogenic microorganisms meant to promote colonization resistance; they are not recommended for acute diarrhea, except in cases of postantibiotic-associated illness (13). In a large meta-analysis of 26 studies, there was no evidence that taking probiotics during pregnancy had any deleterious effect on birth, infant, or maternal outcomes (20). Empiric antibiotics. Empiric antibiotics are not routinely used in acute diarrhea because symptoms are often short lived and secondary to viruses (13). Antibiotics should be considered in patients with severe disease warranting hospitalization and features suggestive of invasive bacterial infection with bloody stools. However, enterotoxin-producing E. coli is in the differential for bloody stools, and there is the possibility of inducing hemolytic uremic syndrome with antibiotic use in that setting (21). Therefore, it is important to withhold empiric antibiotic therapy pending the results of stool testing to rule out enterotoxin-producing E. coli infection. Certain antibiotics are contraindicated or should be used with caution during pregnancy, including metronidazole in the first trimester (potential risk of birth defects), tetracyclines in the last half of pregnancy (risk of hepatotoxicity in the mother and potential for permanent teeth discoloration in the fetus and impairment of fetal long bone growth), and sulfa antibiotics (potential congenital malformations if used in the first trimester as well as jaundice and hemolytic anemia when used in the last month of pregnancy). Acute diarrhea from Clostridioides difficile. The Infectious Diseases Society of America recommends vancomycin 125 mg 4 times a day or fidaxomicin 200 mg twice a day for 10 days for the treatment of C. difficile. Both antibiotics are safe to use in pregnancy. Acute febrile diarrhea from Listeria monocytogenes. The American College of Obstetricians and Gynecologists recommends the use of high-dose aminopenicillin for at least 14 days or until delivery for symptomatic, febrile patients diagnosed with Listeria monocytogenes (ampicillin intravenously 6–12 g/d or amoxicillin orally 100 mg/kg/d) (22). Gentamicin synergy is also considered first line, in combination with ampicillin/amoxicillin for 3–5 days (23). In summary, the management of acute diarrhea in a pregnant woman consists of oral rehydration, dietary changes, and loperamide for severe symptoms. Exacerbation of chronic diarrhea/IBS-D Antidiarrheals/bile acid sequestrants (see acute diarrhea) 5-HT3 receptor antagonists. 5-HT3 receptor antagonists inhibit peristalsis, which slows colonic transit time to allow more water absorption, leading to formed stool. Alosetron is FDA-approved for IBS-D but has a black-box warning for the rare event of ischemic colitis and serious complications of constipation and, hence, should not be initiated during pregnancy. Animal reproduction studies failed to demonstrate a risk to the fetus, and although there are no adequate studies in humans, alosetron does not need to be discontinued during pregnancy if it is clearly needed (15). Ondansetron has demonstrated efficacy in IBS-D, and its use in pregnancy seems safe overall. In a cohort study, the use of ondansetron in the first trimester was associated with an increased risk of oral cleft, whereas a meta-analysis showed no significant association between ondansetron and congenital malformations or adverse pregnancy outcomes (24,25). Rifaximin. Rifaximin is a nonabsorbed oral antibiotic, FDA-approved for the treatment of traveler's diarrhea and IBS-D. There have been no studies of rifaximin in human pregnancy. According to the manufacturer, studies in pregnant rats and rabbits demonstrated craniofacial and skeletal developmental toxicity at higher than normal doses (26). Although its lack of gut absorption should imply that the risk to the fetus is low, until human data are available, the safest course is to avoid this medication in the first trimester. Mixed opioid receptor agonist/antagonist. Eluxadoline is a peripherally acting, mixed mu-opioid and kappa-opioid receptor agonist/delta-opioid receptor antagonist that is US FDA-approved for the treatment of IBS-D. Studies using very high doses in pregnant rats and rabbits did not demonstrate any teratogenic effects (27); however, there are no reports of its use in human pregnancy at this time. Contrarily, buprenorphine, an investigational drug for IBS-D, exhibits good safety data in its approved indication for opioid disorders in pregnancy (28). MANAGEMENT OF FI Assessing for prior obstetric anal sphincter injury Anticipating and proactively managing FI and discussing future delivery in pregnant people with 1 or more prior obstetric anal sphincter injury (OASIS) is important because the risk of FI with prior OASIS and the risk of another OASIS in those with a history of OASIS are significantly increased (29–31). All women who have an episiotomy or a perineal tear at the time of delivery should undergo a rectal examination to evaluate for a rectal or anal sphincter injury. Patients with suspected injuries, which are not apparent on clinical examination, should undergo additional testing with endoanal ultrasound or MRI. Primary repair of the external anal sphincter may be performed using an end-to-end (approximation) or overlap technique immediately or, when resources are not available, within 12 hours of delivery (32). Dietary interventions First-line dietary intervention should include dietary fiber, such as psyllium. Psyllium reduces FI by up to 50% in multiple randomized controlled trials of nonpregnant patients (33,34). Although there are no published studies on the use of fiber to treat FI in pregnancy, a similar efficacy of fiber supplementation is expected in this population. To reduce the incidence of bloating, a slow introduction of supplemental fiber of no more than 5 g/d 1 week at a time is recommended. Target psyllium doses used in clinical trials range from 6 to 16 g/d. There are additional dietary interventions that can focus on beverages and foods that are associated with urgency or loose stools such as dairy, fat-free substitutes, unabsorbable sugars, and caffeine (35). There is also evidence that foods high in fermentable oligosaccharides, disaccharides, and monosaccharides and polyols can cause symptoms of diarrhea, urgency, and FI (36). Although avoidance of fermentable carbohydrates reduces FI symptoms, such a restrictive diet would not be recommended during pregnancy. Lifestyle modifications Potentially modifiable risk factors, such as inactivity and smoking, should be addressed. Certain behavioral techniques to help reduce FI should also be used, such as implementing a toileting scheduling, particularly after meals to help counter the gastrocolic reflex. Kegel exercises that engage the perineal muscles should be performed to reduce episodes of incontinence and when there is fecal urgency (37). Pelvic floor muscle training/biofeedback Learning to engage and strengthen the pelvic floor through pelvic floor muscle training (PFMT) with or without biofeedback may help reduce FI. In nonpregnant patients with FI, the most recent Cochrane review found that biofeedback training or electrical stimulation was more efficacious than PFMT alone in patients who have failed to respond to other conservative measures (38). A Cochrane meta-analysis reported varying interventions on FI outcomes during pregnancy and in the postpartum period (39). In pregnant people with or without FI, PFMT led to little or no difference in the prevalence of FI in late pregnancy. In postpartum patients with persistent FI, it was uncertain whether PFMT reduced incontinence in the late postnatal period compared with usual care (2 trials; 620 participants; very low-quality evidence). For postnatal PFMT in a mixed population, there was considerable uncertainty about the effect on FI in the late postnatal period (107 participants, very low-quality evidence). However, several trials have demonstrated evidence of improvement in FI symptoms after physical therapy in postpartum people with OASIS (40–42). Therefore, after appropriate healing of the sphincter injury postpartum, patients should be referred for pelvic floor therapy. Pharmacologic therapy of FI In the general population, two-thirds of FI episodes are associated with loose stool or diarrhea (43). Medications that reduce diarrhea can be used in pregnant and postpartum patients with FI, with the same caveats stated previously in the acute diarrhea section. In nonpregnant patients, loperamide has been evaluated as a single agent or in combination with other treatments in several randomized controlled studies and has shown efficacy in reducing FI (44,45). In one small prospective trial of nonpregnant older adults, cholestyramine as an adjunct to biofeedback therapy improved stool consistency, reduced stool frequency, and reduced the number of incontinent episodes compared with biofeedback alone (46). Perianal injection of bulking agents The use of an injectate that is composed of dextranomer microspheres stabilized with hyaluronic acid to augment the native anal sphincter can be considered in nonpregnant patients with FI who have failed conservative medical therapies and can be offered in people who suffer from FI before a pregnancy (47). Anal inserts Anal inserts which temporarily occlude the anal canal and prevent stool leakage are an option for pregnant patients with FI. Renew inserts are a single-use, disposable silicone device that are expelled at defecation. In a multicenter, open-label study of 73 patients, 78% had a ≥ 50% reduction of FI and were very or extremely satisfied with the result, with a median reduction of 0.9–0.2 episode/d (48). In this trial, 35% of subjects dropped out because of complaints of feeling constant rectal pressure. This device could be considered for patients with low-grade FI and soilage; however, these are currently no longer commercially available in the United States because of US Food and Drug Administration import restrictions. Other therapies Other therapies have been studied in the nonpregnant population, and no data are available regarding the safety and efficacy of their use during pregnancy. The vaginal bowel control system (Eclipse System) is a vaginal device with an inflatable balloon that occludes the rectal vault and prevents incontinence. Richter et al (49) demonstrated that 86% of patients achieved treatment success (>50% reduction in FI events) and 41% attained continence. The most common adverse event was vaginal wall injury, with most adverse events (90/134, 67%) occurring during the fitting period. In patients with moderate-to-severe FI who have failed to respond to more conservative measures, sacral nerve stimulation (SNS) can be considered. SNS is believed to improve FI by chronically stimulating the sacral nerves, the surrounding muscles, and the production of colonic retrograde propagated contractions, thus delaying colonic transit and delivery of stool to the rectum (50). SNS is effective in improving FI and is also durable with up to 89% of subjects reporting persistent reduction and relief from FI at 5 years (51,52). Studies have demonstrated good results even in patients with known sphincter defects, regardless of the degree of the defect (53,54). In concept, percutaneous tibial nerve stimulation (PTNS) is comparable with SNS and is used for the treatment of urinary incontinence. Initial trials of PTNS showed promise in FI subjects; however, 2 subsequent, large, randomized controlled trials failed to demonstrate a difference in FI clinical outcomes between different study arms (55,56). Therefore, PTNS is not recommended as a primary treatment of FI alone but as a noninvasive treatment option in those with concurrent urinary incontinence. CONCLUSION Both diarrhea and FI are not uncommon during pregnancy and the postpartum period. The causes of diarrhea in pregnancy are similar to those in the nonpregnant population, and the evaluation is reflective of this. Acute diarrhea is managed with dietary modification, rehydration, and a judicious use of loperamide. C. difficile and Listeria infections carry significant morbidity in pregnant patients and should be recognized and treated effectively. The first-line treatment of FI, regardless of pregnancy status, involves noninvasive strategies, such as dietary and lifestyle changes, control of diarrhea, and PFMT. Postpartum patients can be referred for PFMT 6–8 weeks from OASIS repair. If these noninvasive strategies fail, patients can be considered for sphincter augmentation using injectable bulking agents or for a vaginal insert in the postpartum period. Continued failure to respond to these measures would warrant stepwise escalation to minimally invasive options, such as SNS, and surgical interventions, such as secondary sphincteroplasty repair or fecal diversion surgery for the most severe cases. CONFLICTS OF INTEREST Guarantor of the article: Stacy B. Menees, MD, MS. Financial support: This article appeared as part of the ACG Monograph on GI Diseases and Endoscopy in Pregnancy and Postpartum Period. Unrestricted educational grants to support the monograph have been provided to the ACG Institute for Clinical Research & Education from UCB, Inc., Ferring Pharmaceuticals, Inc., and Janssen Biotech, Inc. Potential competing interests: AL is a consultant for Takeda Pharmaceuticals, AbbVie, and Janssen Biotech, and received honoraria from Pfizer and Lilly. SBM has received consulting fees from Takeda Pharmaceuticals.BEST PRACTICE RECOMMENDATIONS ✓ Diarrhea should be assessed and managed in a timely manner because dehydration can lead to serious risks to the pregnancy. Provide adequate rehydration with an oral rehydration solution, and use loperamide for severe diarrhea. ✓ Most acute diarrhea are due to self-limited viral infections. However, a high index of suspicion should be maintained for C. difficile and listeriosis infections because both are associated with high morbidity of the pregnant patient and the fetus. ✓ Ask pregnant persons about fecal incontinence if they have associated diarrhea. If fecal incontinence is present, treat with dietary modification, fiber supplements, and pelvic floor muscle therapy.