Metritis

Metritis is a serious inflammatory condition affecting the uterus of mares, characterized by infection and inflammation of all layers of the uterine wall. This condition represents a more severe form of uterine disease compared to endometritis, which affects only the superficial endometrial lining. Metritis involves deeper penetration of infectious agents and inflammatory processes into the myometrium and potentially the perimetrium, making it a significant threat to both the mare's fertility and overall health. The condition requires prompt veterinary attention to prevent serious complications and preserve the mare's reproductive potential.

Metritis occurs in mares of all breeds and ages but is most commonly observed in broodmares, particularly those that have recently foaled or experienced complications during parturition. Post-foaling metritis is especially concerning as it can develop rapidly within the first few days after delivery, often associated with retained fetal membranes, dystocia, or contamination during the foaling process. Mares with compromised immune systems, poor perineal conformation, or histories of reproductive problems face elevated risks of developing this condition.

The impact of metritis on a mare's health and reproductive capacity can be substantial. Acute metritis may cause systemic illness with fever, depression, and toxemia, while chronic cases can lead to permanent uterine damage affecting future fertility. Performance mares may experience decreased athletic ability during active infection, and broodmares may suffer repeated pregnancy losses or complete infertility if the condition is not adequately addressed. The economic implications for breeding operations can be significant when valuable mares are affected.

Fortunately, metritis is treatable when diagnosed early and managed appropriately by an experienced equine veterinarian. Treatment success depends heavily on identifying the causative organisms, addressing predisposing factors, and implementing comprehensive therapeutic protocols. Early detection through regular reproductive examinations and prompt intervention at the first signs of infection dramatically improve outcomes. With proper treatment, many mares can recover fully and return to successful breeding careers, though some cases may require extended treatment periods or result in reduced fertility.

The primary causes of metritis in mares involve bacterial infection of the uterine tissues, with various organisms capable of initiating the disease process. Common bacterial pathogens include Streptococcus equi subspecies zooepidemicus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Taylorella equigenitalis, the causative agent of contagious equine metritis. These organisms typically gain access to the uterus through the cervix, either during breeding, foaling, or through compromised anatomical barriers. Fungal organisms such as Candida and Aspergillus species can also cause metritis, particularly in mares that have received prolonged antibiotic treatment or have compromised immune function.

While metritis is not considered a hereditary condition, certain conformational traits that predispose mares to reproductive infections can be passed from generation to generation. Mares with poor perineal conformation, characterized by a sunken anus or vulvar tilt that allows fecal contamination of the reproductive tract, face significantly higher risks of developing uterine infections. These anatomical predispositions may be more common in certain breed lines, though the condition itself is not genetically transmitted. Additionally, mares that have experienced repeated reproductive problems may pass conformational weaknesses to their offspring.

Environmental and management factors play substantial roles in metritis development. Unsanitary breeding conditions, contaminated breeding equipment, and poor hygiene during reproductive procedures increase infection risk significantly. Mares housed in dirty environments, particularly those with accumulated fecal material near the vulvar area, face elevated contamination risks. The breeding season itself creates challenges, as repeated covering or artificial insemination increases opportunities for bacterial introduction. Natural cover breeding carries additional risks of sexually transmitted organisms compared to artificial insemination with properly handled semen.

Several risk factors increase a mare's susceptibility to metritis beyond environmental contamination. Age plays a significant role, with older mares demonstrating decreased uterine clearance mechanisms and increased vulnerability to persistent infections. Mares that have foaled multiple times may have compromised cervical competence, allowing easier bacterial access. Nutritional status affects immune function, with undernourished or stressed mares showing reduced ability to combat uterine infections. Mares undergoing immunosuppressive treatments or suffering from concurrent illnesses face heightened risks of developing metritis when exposed to pathogenic organisms.

The pathophysiology of metritis involves bacterial colonization of uterine tissues followed by inflammatory response activation. Once organisms breach the cervical barrier and establish themselves within the uterine lumen, they begin proliferating and invading deeper tissue layers. The mare's immune system responds with inflammatory mediator release, neutrophil migration, and fluid accumulation within the uterus. In severe cases, bacterial toxins enter systemic circulation, causing endotoxemia with widespread effects including fever, cardiovascular compromise, and potential laminitis development. The depth of tissue involvement distinguishes metritis from superficial endometritis, with metritis potentially causing permanent structural damage to the uterine wall if not treated promptly and effectively.

Early warning signs of metritis in mares can be subtle, as horses naturally tend to hide signs of illness as a survival mechanism inherited from their prey animal ancestry. Initial indicators may include mild behavioral changes such as decreased appetite, slight lethargy, or reduced interaction with herd mates. Observant handlers might notice the mare standing with her tail slightly elevated or appearing uncomfortable in the hindquarter region. Some mares display subtle changes in attitude, becoming quieter than normal or showing mild irritability when handled. These early signs are easily overlooked but represent crucial opportunities for early intervention before the condition progresses to more serious stages.

Common symptoms of established metritis include vulvar discharge, which ranges from thin and watery to thick, purulent, and malodorous depending on the causative organisms and severity of infection. This discharge may be visible on the mare's tail, hindquarters, or stall bedding, and often has an unpleasant odor that differs noticeably from normal reproductive secretions. The vulvar area may appear swollen or irritated, with some mares showing obvious discomfort when the perineal region is touched or examined. Frequent urination posturing without actually urinating may occur as the mare experiences discomfort from uterine inflammation.

Behavioral changes become more pronounced as metritis progresses. Affected mares typically demonstrate depression, standing with lowered heads and showing little interest in their surroundings or feed. Appetite reduction is common, with some mares refusing grain entirely while others eat only hay or show intermittent interest in food. Mares may paw at the ground or exhibit mild colic-like signs due to abdominal discomfort associated with uterine distension and inflammation. Social interactions change noticeably, with normally gregarious mares becoming withdrawn and less responsive to human interaction or herd dynamics.

Physical signs observable on examination include elevated body temperature, often ranging from 101.5 to 104 degrees Fahrenheit or higher in severe cases. Heart rate and respiratory rate typically increase proportionally to fever severity and systemic involvement. The mare's coat may appear dull and rough, with some animals showing signs of dehydration including tacky mucous membranes and prolonged skin tent response. Weight loss occurs rapidly in severe cases due to combined effects of reduced feed intake and metabolic demands of fighting infection. Rectal examination often reveals uterine enlargement, increased uterine tone, and pain response when the reproductive tract is palpated.

Symptom progression in untreated or inadequately treated metritis can be alarming. What begins as mild discharge and behavioral changes can escalate to severe systemic illness within days. The discharge volume typically increases while becoming more purulent and foul-smelling. Fever spikes higher, and the mare becomes increasingly depressed and unwilling to move or eat. Abdominal pain may intensify, and signs of endotoxemia including elevated heart rate, brick-red or purple mucous membranes, and cool extremities may develop. Some mares develop concurrent laminitis as a result of systemic toxemia, adding a potentially life-threatening complication to an already serious condition.

Emergency symptoms requiring immediate veterinary care include high fever exceeding 103 degrees Fahrenheit, profuse malodorous discharge, severe depression or inability to rise, signs of colic or abdominal pain, evidence of laminitis such as reluctance to walk or shifting weight between feet, and any signs of cardiovascular compromise including racing heart rate, abnormal mucous membrane color, or cold extremities. Post-foaling mares showing any combination of these signs require urgent evaluation, as post-partum metritis can deteriorate rapidly and become life-threatening within hours. Any mare with retained placenta for more than three hours post-foaling should be considered at high risk for developing metritis and requires immediate veterinary attention.

Physical examination forms the foundation of metritis diagnosis in mares. The veterinarian begins with a thorough general assessment including vital signs measurement, evaluation of mucous membrane color and capillary refill time, and assessment of overall body condition and attitude. External examination of the perineal region reveals discharge characteristics, vulvar swelling, and conformational abnormalities that may predispose to infection. The tail and hindquarters are inspected for evidence of discharge accumulation, and the mare's overall demeanor and response to handling are noted. This initial assessment helps determine the severity of illness and guides subsequent diagnostic steps.

Diagnostic testing for metritis encompasses both reproductive-specific evaluations and systemic health assessments. Transrectal palpation allows the veterinarian to assess uterine size, tone, and presence of fluid or abnormal contents. Complete blood count reveals elevated white blood cell counts in most cases, with neutrophilia indicating active bacterial infection. Serum chemistry panels help evaluate organ function and detect complications such as kidney or liver involvement from systemic infection. Fibrinogen levels are often elevated, providing additional evidence of inflammation. Culture samples collected from uterine discharge or directly from the uterine lumen identify the causative organisms and guide antibiotic selection through sensitivity testing.

Advanced diagnostics significantly enhance metritis evaluation and treatment planning. Transrectal ultrasound examination provides detailed visualization of uterine contents, wall thickness, and structural abnormalities. Free fluid within the uterine lumen appears as characteristic anechoic or hypoechoic areas, and the degree of uterine wall thickening can be measured. Ultrasound also allows assessment of ovarian structures and detection of concurrent reproductive abnormalities. Endometrial biopsy may be recommended in chronic cases to evaluate the degree of permanent uterine damage and provide prognostic information regarding future fertility. Hysteroscopy, while less commonly performed, allows direct visualization of the uterine lining and identification of focal lesions or foreign material.

Differential diagnosis for metritis includes several conditions presenting with similar clinical signs. Pyometra, characterized by pus accumulation within a closed cervix, shares many symptoms but differs in cervical status and treatment approach. Endometritis affects only the superficial uterine lining and typically presents with less severe systemic signs. Retained placenta must be identified as it often predisposes to or accompanies metritis. Other causes of vulvar discharge including cervicitis, vaginitis, and urinary tract infections require differentiation through careful examination. Systemic illnesses causing fever and depression such as viral infections, pleuropneumonia, or peritonitis may initially appear similar to metritis, particularly when reproductive discharge is minimal or absent. Thorough diagnostic workup ensures accurate diagnosis and appropriate treatment implementation.

Emergency and immediate treatment for acute metritis focuses on stabilizing the mare and beginning aggressive therapy to combat infection. Intravenous fluid therapy addresses dehydration and supports cardiovascular function, particularly critical in mares showing signs of endotoxemia. Anti-inflammatory medications including flunixin meglumine help control fever, reduce pain, and provide important anti-endotoxic effects. Broad-spectrum systemic antibiotics are initiated immediately based on likely causative organisms, with therapy adjusted once culture and sensitivity results become available. Mares with severe systemic compromise may require intensive care including plasma transfusion, vasopressor support, and careful monitoring of vital parameters around the clock.

Medical management of metritis involves comprehensive antibiotic therapy targeting identified pathogens combined with local uterine treatment. Systemic antibiotics are selected based on culture results, tissue penetration characteristics, and safety profiles, with common choices including trimethoprim-sulfamethoxazole combinations, gentamicin, or penicillin derivatives depending on organism sensitivity. Uterine lavage using large volumes of sterile saline or lactated Ringer's solution mechanically removes purulent material and bacteria from the uterine lumen. Following lavage, intrauterine antibiotic infusion delivers high local antibiotic concentrations directly to infected tissues. Treatment frequency and duration depend on severity and response, with daily lavage often required initially, tapering as the mare improves.

Surgical options for metritis are limited but may become necessary in specific circumstances. Mares with retained fetal membranes that cannot be safely removed manually may require careful surgical extraction to prevent further uterine damage while eliminating this source of ongoing contamination. Severe cases with uterine rupture or necrosis require emergency surgical intervention, though prognosis in such situations is guarded. Caslick's procedure, a minor surgical correction of vulvar conformation, may be performed once active infection resolves to prevent future contamination in mares with poor perineal anatomy. Ovariectomy is rarely indicated but may be considered for mares with intractable chronic infections where eliminating reproductive cycling offers the best chance for resolution.

Supportive care measures complement specific anti-infective therapy in managing metritis. Nutritional support ensures adequate caloric intake during recovery, with palatable feeds offered frequently to encourage eating in depressed mares. Pain management beyond anti-inflammatories may include additional analgesics if the mare shows significant discomfort. Environmental management places the mare in clean, dry, well-bedded housing that minimizes stress and prevents additional contamination. Careful monitoring of potential laminitis development is essential, with soft footing and foot care implemented prophylactically in high-risk cases. Probiotics may help restore normal gastrointestinal flora in mares receiving prolonged antibiotic therapy.

Rehabilitation and return to work or breeding follows different timelines depending on the mare's use and severity of infection. Broodmares typically require multiple negative uterine cultures obtained over several estrous cycles before breeding is attempted again, a process that may take three to six months. Treatment continues through several cycles to ensure complete resolution and verify the uterus has regained normal function. Performance mares may return to light work once fever resolves and systemic signs improve, with gradual increase in activity as recovery progresses. Full athletic work typically waits until complete resolution is confirmed, preventing relapse from the stress of intense exercise.

Treatment decision factors include the mare's age, reproductive history, intended use, and economic considerations. Young, valuable broodmares may warrant aggressive, prolonged treatment to preserve fertility even at significant cost. Older mares or those with extensive uterine damage visible on biopsy may have poor prognoses for future fertility regardless of treatment intensity, influencing decisions about treatment extent. Performance mares without breeding value may focus on faster return to athletic function rather than reproductive preservation. Owner financial constraints and the mare's individual response to initial therapy also guide treatment intensity and duration decisions. Throughout treatment, open communication between veterinarian and owner ensures treatment goals remain realistic and aligned with the mare's best interests.

Recovery timeline for metritis varies considerably based on infection severity, causative organisms, treatment response, and individual mare factors. Acute post-foaling metritis caught early may show significant improvement within seven to fourteen days of intensive treatment, with complete resolution achieved within four to six weeks. More severe or chronic cases require extended treatment periods of two to three months or longer before the uterus returns to normal condition. Throughout recovery, regular veterinary rechecks assess progress through physical examination, ultrasound evaluation, and periodic cultures to confirm infection clearance. Mares should show progressive improvement with decreasing discharge, normalizing vital signs, and improving attitude and appetite within the first week of appropriate treatment.

Post-treatment care and monitoring extend well beyond apparent clinical recovery. Serial uterine cultures, typically obtained during estrus when the cervix is relaxed, confirm bacterial elimination and guide decisions about breeding timing. Ultrasound examinations monitor uterine size reduction, fluid clearance, and wall thickness normalization. Endometrial cytology, examining cells collected from the uterine lining, provides additional information about ongoing inflammation even when cultures are negative. Many veterinarians recommend at least two to three negative cultures obtained during separate estrous cycles before considering the mare cleared for breeding. Continued attention to vulvar conformation and hygiene practices helps prevent reinfection during the vulnerable post-treatment period.

Prognosis factors influencing long-term outcomes include the depth of uterine damage, mare's age, promptness of treatment initiation, and presence of predisposing conformational defects. Mares treated early in the disease process before extensive tissue damage occurs generally have excellent prognoses for both health and fertility. Chronic metritis cases with fibrosis and permanent endometrial changes face more guarded fertility prognoses, though they may maintain normal health. Older mares with decreased natural uterine clearance mechanisms may struggle with recurrent infections despite successful initial treatment. Mares with poor perineal conformation require surgical correction to prevent reinfection and achieve lasting resolution.

Long-term fertility outlook depends significantly on degree of endometrial damage sustained during infection. Mares recovering from mild to moderate metritis without extensive tissue destruction often return to normal fertility with conception rates comparable to their pre-infection baseline. Those with chronic infection may have decreased conception rates, increased early embryonic loss, or higher susceptibility to future uterine infections. Endometrial biopsy provides the most accurate prognostic information, grading uterine tissue changes and predicting expected foaling rates. Many mares with Category I or IIA biopsies maintain good fertility, while those with Category III changes face significantly reduced chances of carrying foals to term. Despite guarded fertility prognoses, most mares recover their general health completely and can continue athletic careers or serve as companion animals even if breeding is no longer advisable.

Management practices form the cornerstone of metritis prevention in broodmares. Maintaining excellent hygiene during all reproductive procedures dramatically reduces infection risk. Breeding areas should be clean, with handlers using proper sterile technique when performing artificial insemination or assisting with natural cover. Stallion hygiene matters equally, with regular sheath cleaning and culture screening of breeding stallions preventing transmission of pathogenic organisms. Post-breeding uterine lavage, performed within twenty-four to forty-eight hours of cover in susceptible mares, helps clear contamination before infection establishes. Veterinary examination before each breeding cycle identifies subclinical infections that could worsen with the cervical relaxation and uterine manipulation of breeding.

Nutritional prevention supports optimal immune function and reproductive health. Well-balanced diets meeting all vitamin and mineral requirements maintain the mare's natural disease resistance. Adequate protein intake supports tissue repair and immune cell production. Trace mineral supplementation, particularly selenium in deficient areas, contributes to reproductive health. Body condition maintenance between four and six on the nine-point scale provides energy reserves for immune function without obesity-related complications. Pregnant mares require appropriate nutritional increases during late gestation to support both fetal development and maternal reserves needed for foaling and postpartum recovery.

Exercise and conditioning contribute to overall health that supports reproductive disease resistance. Fit mares generally have stronger immune function and better post-foaling recovery than sedentary animals. Moderate exercise during pregnancy, appropriate to the individual mare's fitness level and stage of gestation, maintains cardiovascular health and muscle tone beneficial for foaling. Post-foaling exercise, once veterinary cleared, promotes uterine involution and helps restore normal reproductive tract function. However, excessive stress from overtraining can suppress immune function, requiring balance between fitness benefits and immunological demands.

Environmental factors significantly influence metritis risk. Clean, dry stall conditions minimize bacterial load in the mare's environment. Regular manure removal and proper bedding maintenance reduce fecal contamination of the perineal area. Foaling areas require particular attention to cleanliness, with fresh bedding and disinfected surfaces reducing pathogen exposure during the vulnerable periparturient period. Pasture management includes avoiding muddy areas that promote fecal-vulvar contact. Adequate shelter protects mares from environmental stressors that compromise immune function. Well-designed facilities with appropriate ventilation reduce airborne pathogen exposure while maintaining comfortable temperature ranges.

Reproductive management protocols specifically targeting metritis prevention include pre-breeding examinations to identify susceptible mares before problems develop. Mares with poor perineal conformation benefit from Caslick's procedure before breeding season to prevent contamination during pregnancy. Post-foaling monitoring ensures prompt identification of retained placenta or early infection signs, allowing immediate intervention. Routine post-foaling uterine examination at seven to fourteen days detects subclinical infections before they progress to clinical metritis. For mares with histories of reproductive infection, prophylactic uterine lavage and antibiotic infusion after breeding may prevent infection establishment. These proactive approaches prove far more effective and economical than treating established metritis after clinical signs develop.

Daily management adjustments for mares recovering from or susceptible to metritis focus on minimizing infection risk while supporting reproductive health. Housing should prioritize cleanliness, with stalls cleaned thoroughly at least twice daily and fresh bedding added as needed to maintain dry conditions. Handlers should pay particular attention to keeping the mare's hindquarters clean, removing any manure or debris that accumulates around the tail and perineal area. For mares with Caslick's procedures, daily visual inspection ensures the vulvar closure remains intact and no discharge accumulates. Feed and water management ensures optimal nutrition for immune support, with clean water available at all times and quality forage forming the diet foundation.

Housing and turnout considerations balance the benefits of movement and social interaction against infection risks. Individual turnout in clean, well-maintained pastures provides exercise and mental stimulation without the contamination risks of communal areas. Mares recovering from metritis may initially require limited turnout duration, gradually increasing as their condition improves. Avoid turnout in muddy paddocks where fecal material can contact the vulvar area. Group turnout decisions should consider the mare's reproductive status, with pregnant mares separated from potentially aggressive herd members and open mares managed to prevent unplanned breeding. Shelter access provides protection from weather extremes that could stress the mare's immune system.

Exercise modifications during metritis recovery and prevention differ from normal training protocols. During active infection treatment, exercise is typically restricted to hand walking or small paddock turnout that allows movement without exhaustion. As treatment progresses and the mare improves, light riding or lunging may resume based on veterinary guidance. Full work returns only after complete infection resolution is confirmed. For mares in metritis prevention programs, regular moderate exercise maintains fitness and immune function without the stress of intense training. Pregnant mares continue appropriate exercise throughout gestation, modified as pregnancy advances, to maintain health beneficial for uncomplicated foaling.

Monitoring and ongoing care requirements extend well beyond initial treatment completion. Daily observation for any discharge, behavioral changes, or signs of illness catches potential problems early. Temperature monitoring may be recommended during high-risk periods such as post-foaling or post-breeding. Regular veterinary reproductive examinations throughout the breeding season track uterine health and identify developing problems before clinical disease appears. Owners should maintain detailed records of breeding dates, treatments, examination findings, and any abnormalities observed, providing valuable information for ongoing management decisions. Communication with the veterinarian about any concerns, no matter how minor they seem, ensures timely intervention when needed.

Quality of life and use considerations for mares affected by metritis depend on recovery completeness and long-term effects. Mares recovering fully from acute metritis typically return to their previous use without restriction, whether breeding or performance. Those with chronic changes affecting fertility may transition from breeding programs to performance careers or comfortable retirement as riding horses or companions. Even mares with significantly compromised reproductive tracts can enjoy excellent quality of life in non-breeding roles. The emotional wellbeing of mares should not be overlooked, with attention to herd social needs, mental stimulation through varied activities, and positive human interaction contributing to overall health. Decisions about continued breeding attempts versus retirement from reproduction should prioritize the mare's welfare alongside owner goals and economic considerations.

While metritis can affect mares of any breed, certain characteristics increase susceptibility across breed lines. Thoroughbreds and other breeds selected for athletic performance sometimes exhibit poor perineal conformation as a consequence of selection for other traits, predisposing them to reproductive tract contamination. Older mares within any breed face increased risk due to age-related changes in cervical competence and uterine clearance mechanisms. Draft breeds including Clydesdales, Percherons, and Belgians may face increased dystocia risk due to fetal size, with difficult births predisposing to post-foaling metritis. Individual variation within breeds matters more than breed averages, with conformational assessment of each mare providing better risk prediction than breed generalizations.

Use and discipline influence metritis risk more significantly than breed identity in many cases. Heavily campaigned broodmares bred repeatedly each season face cumulative reproductive tract stress that increases infection susceptibility over time. Mares used as embryo transfer donors undergo frequent uterine manipulation that may increase contamination opportunities despite careful technique. Performance mares transitioning to breeding careers later in life may have undetected subclinical reproductive issues that manifest when breeding attempts begin. Race mares often have Caslick's procedures performed early in their careers, and proper timing of opening and reclosing these surgical modifications around breeding and foaling affects infection risk significantly.

Genetic testing and breeding recommendations for metritis focus on conformational selection rather than specific genetic markers. Responsible breeding programs evaluate mare conformation before including individuals in breeding plans, avoiding propagation of traits predisposing to reproductive infections. Stallion selection should similarly consider whether the cross might produce offspring with problematic conformational characteristics. Screening mares for contagious equine metritis and other sexually transmitted pathogens protects breeding operations from introducing these organisms. Documentation of reproductive histories across generations helps identify family lines with higher infection susceptibility, guiding breeding decisions. These considerations support production of offspring with optimal reproductive health potential while addressing metritis risk at the population level.

Commonly co-occurring conditions with metritis include endometritis, which represents superficial uterine lining inflammation and often precedes or follows metritis. Retained fetal membranes frequently accompany or precede post-foaling metritis, with the decomposing placental tissue providing an ideal bacterial growth medium. Pyometra, characterized by pus accumulation within a closed cervix, may develop from untreated metritis when the cervix closes over infected uterine contents. Laminitis represents a serious systemic complication of metritis, developing secondary to endotoxemia when bacterial toxins trigger inflammation in the hoof laminae. Cervicitis and vaginitis may occur concurrently with metritis as part of ascending reproductive tract infection affecting multiple anatomical areas.

Conditions presenting with similar symptoms to metritis require careful differentiation. Pyometra shares many clinical signs but differs in treatment approach and prognosis. Post-foaling hemorrhage or hematoma can cause vulvar discharge and systemic signs resembling infection. Urinary tract infections produce discharge and fever that may be confused with reproductive tract disease. Vaginal varicose vein rupture, particularly in older mares, causes bloody discharge without infection. Uterine tumors including leiomyoma and lymphoma may produce discharge and reproductive changes mimicking infectious metritis. Systemic illness from any cause can produce the fever and depression seen with metritis, requiring thorough examination to identify the true disease source.

Potential complications of metritis extend beyond the reproductive tract when the condition is severe or inadequately treated. Laminitis remains the most feared complication, potentially causing permanent lameness or necessitating euthanasia in severe cases. Septicemia may develop when bacteria enter the bloodstream, spreading infection to distant organs including joints, kidneys, and heart valves. Peritonitis can occur if uterine infection extends through the uterine wall to involve the abdominal cavity. Chronic metritis may result in pyometra formation, adhesion development, or permanent endometrial scarring affecting fertility. Recurrent infection susceptibility often follows metritis episodes, with affected mares requiring intensive management to prevent future occurrences. Early recognition and aggressive treatment of metritis significantly reduce complication risks and improve long-term outcomes.