{"paper_id":"b4533aeb-82ca-4e58-bbd3-a0b9afa2162c","body_text":"Review began\n 09/22/2026 \nReview ended\n 10/11/2026 \nPublished\n 10/13/2026\n© Copyright \n2026\nKumar et al. This is an open access article\ndistributed under the terms of the Creative\nCommons Attribution License CC-BY 4.0.,\nwhich permits unrestricted use, distribution,\nand reproduction in any medium, provided\nthe original author and source are credited.\nDOI:\n 10.7759/cureus.117835\nA Rare Association of Bladder Endometriosis,\nUnicornuate Uterus, and Hematometra: A Case\nReport\nPranesh K. Kumar \n, \nVamshi C. Yadav \n, \nDavneet Singh \n, \nJagadeeshwar Thirukovela \n,\nPanduranga Rao Karnam \n1.\n Urology, Employees' State Insurance Corporation (ESIC) Medical College, Hyderabad, Hyderabad, IND\nCorresponding author: \nPranesh K. Kumar, \npraneshkumarkandi@gmail.com\nAbstract\nEndometriosis involving the urinary tract is uncommon, with the urinary bladder being the most frequently\naffected site. Its nonspecific urinary manifestations may result in delayed diagnosis. Congenital Müllerian\nanomalies, particularly a unicornuate uterus with a noncommunicating functional rudimentary horn, may\nbe associated with hematometra and endometriosis secondary to obstructed menstrual outflow and\nretrograde menstruation. We report an unusual coexistence of bladder endometriosis, a right unicornuate\nuterus with a noncommunicating left rudimentary cavity, and hematometra in a 22-year-old nulliparous\nwoman who presented with a one-year history of cyclical dysuria, hematuria, and dyspareunia. She had\nregular menstrual cycles associated with dysmenorrhea and had attempted conception without success.\nPelvic magnetic resonance imaging demonstrated a right hemi-uterus measuring approximately 7 × 3 × 2.5\ncm and a separate left-sided endometrial cavity measuring 4.1 × 3.5 × 4.2 cm, which did not communicate\nwith the uterus and was distended with hematometra. An ill-defined T2 hypointense lesion measuring 3.4 ×\n2.3 × 3 cm with T1 hyperintense foci was centered in the vesicouterine pouch, extending posteriorly into the\nlower uterine segment and cervix and anteriorly into the bladder wall with intraluminal extension.\nThickening of the proximal bilateral round ligaments was also noted, with the overall appearance suggestive\nof deep pelvic endometriosis. Cystoscopy showed multiple reddish-brown cystic lesions involving the lateral\nand posterior walls of the urinary bladder. Near-complete transurethral resection of the bladder lesions was\nperformed, along with laparoscopic drainage and partial excision of the rudimentary horn.\nHistopathological examination of the resected bladder lesions confirmed bladder endometriosis.\nPostoperatively, the patient was started on leuprolide acetate and remained symptom-free at six-month\nfollow-up. This case highlights the importance of considering bladder endometriosis in young women\npresenting with cyclical urinary symptoms and demonstrates the value of magnetic resonance imaging in\ndelineating Müllerian anomalies, hematometra, and the extent of deep pelvic endometriosis. The\ncoexistence of extensive bladder endometriosis with a unicornuate uterus and hematometra underscores the\nimportance of coordinated urological and gynecological management.\nCategories:\n Urology, Obstetrics/Gynecology\nKeywords:\n bladder endometriosis, cyclical hematuria, deep pelvic endometriosis, hematometra, müllerian anomaly,\nunicornuate uterus\nIntroduction\nEndometriosis is a chronic inflammatory condition characterized by the presence of endometrial-like tissue\noutside the uterine cavity. Although it predominantly affects the pelvic reproductive organs, extragenital\ninvolvement can occur. Urinary tract endometriosis is uncommon, occurring in approximately 1% of\npatients with endometriosis, with the urinary bladder being the most frequently affected site \n[1,2]\n. Bladder\nendometriosis may present with dysuria, urinary frequency, pelvic pain, and hematuria. Although cyclical\nhematuria is considered a characteristic manifestation, it occurs in only a minority of patients.\nConsequently, urinary tract endometriosis may be overlooked or misdiagnosed as a more common urological\ncondition \n[1,2]\n.\nBladder endometriosis is frequently associated with deep infiltrating endometriosis involving the anterior\npelvic compartment. Magnetic resonance imaging (MRI) is valuable for detecting and characterizing deep\ninfiltrating endometriosis and for determining its relationship with adjacent pelvic organs. MRI can\ndemonstrate the location, depth, and extent of bladder involvement and therefore plays an important role in\npreoperative planning \n[3]\n.\nCongenital Müllerian anomalies represent a spectrum of developmental abnormalities of the female\nreproductive tract. A unicornuate uterus results from incomplete development of one Müllerian duct and\nmay be associated with a rudimentary horn. When a functional rudimentary horn does not communicate\nwith the main uterine cavity, menstrual blood may accumulate within it, resulting in hematometra.\nObstructed menstrual outflow and retrograde menstruation may contribute to the development of\nendometriosis and may also have implications for fertility \n[4,5]\n.\n1\n1\n1\n1\n1\n \nOpen Access Case Report\nHow to cite this article\nKumar P K, Yadav V C, Singh D, et al. (October 13, 2026) A Rare Association of Bladder Endometriosis, Unicornuate Uterus, and Hematometra: A\nCase Report. Cureus 18(10): e117835. \nDOI 10.7759/cureus.117835\n\nThe coexistence of a unicornuate uterus with a noncommunicating rudimentary horn, hematometra, and\nbladder endometriosis is uncommon, with only a limited number of cases described in the literature. A\nprevious report documented a unicornuate uterus with a noncommunicating rudimentary horn containing\nhematometra and a communicating bladder endometriotic nodule \n[6]\n. Extensive bladder involvement in this\nsetting may pose diagnostic and therapeutic challenges because of the proximity of the bladder to the uterus\nand other pelvic structures. Recognizing the underlying Müllerian anomaly is therefore important for\ndefining the extent of disease and planning appropriate treatment. The present case describes extensive\ndeep pelvic endometriosis involving the urinary bladder, with intraluminal extension, in association with a\nunicornuate uterus and hematometra. We discuss the clinical, radiological, cystoscopic, operative, and\nhistopathological findings, highlighting the diagnostic and therapeutic considerations in this unusual\npresentation.\nCase Presentation\nA 22-year-old nulliparous woman presented with a one-year history of dysuria, hematuria, and dyspareunia.\nHer urinary symptoms were present throughout the menstrual cycle but worsened during menstruation. She\nreported regular menstrual cycles associated with dysmenorrhea and had attempted conception but had not\nconceived. The cyclical exacerbation of her urinary and pelvic symptoms raised clinical suspicion of\nendometriosis.\nOn abdominal examination, the patient had mild pelvic tenderness, with no other significant findings.\nInitial investigations included an unremarkable urinalysis and a urine culture showing no bacterial growth.\nUltrasonography of the abdomen revealed multiple small bladder masses, a unicornuate uterus, and\nhematometra, prompting further evaluation with magnetic resonance imaging (MRI).\nMRI of the pelvis with plain and contrast sequences demonstrated a right-sided hemi-uterus measuring\napproximately 7 × 3 × 2.5 cm, consistent with a unicornuate uterus. A separate left-sided endometrial cavity\nmeasuring approximately 4.1 × 3.5 × 4.2 cm did not communicate with the main uterine cavity and was\ndistended with hematometra, as seen in Figure \n1\n.\nFIGURE\n 1: Pelvic MRI demonstrating a unicornuate uterus and a\nnoncommunicating rudimentary uterine cavity containing hematometra.\nMRI also demonstrated an ill-defined T2-hypointense lesion measuring approximately 3.4 × 2.3 × 3 cm,\ncontaining T1-hyperintense foci and centered in the vesicouterine pouch. The lesion extended posteriorly\ninto the lower uterine segment and cervix, and anteriorly into the bladder wall and lumen. It demonstrated\nmild heterogeneous enhancement following contrast administration (Figure \n2\n). Focal thickening of the\njunctional zone along the right lateral uterine wall, measuring approximately 1.5 cm, was considered\npossibly consistent with focal adenomyosis. Thickening of the proximal portions of both round ligaments\nwas also noted.\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n2\n of \n8\n\nFIGURE\n 2: Axial pelvic MRI demonstrating an infiltrative lesion centered\nin the vesicouterine pouch, extending into the bladder wall and lumen,\nwith posterior extension towards the lower uterine segment and cervix.\nThe right ovary measured approximately 3 × 1.8 cm and contained small subcentimetric T1-hyperintense\ncystic lesions. The left ovary measured approximately 4 × 1.7 cm and contained multiple cystic lesions,\nincluding a T1-hyperintense cyst. These findings were considered possibly representative of endometriotic\ncysts. No free fluid or pelvic or inguinal lymphadenopathy was identified.\nCystoscopy subsequently demonstrated multiple reddish-brown cystic lesions within the urinary bladder,\npredominantly involving the lateral and posterior walls (Figure \n3\n).\nFIGURE\n 3: Cystoscopic appearance of multiple reddish-brown lesions\ninvolving the lateral and posterior walls of the urinary bladder.\nIn view of the imaging and cystoscopic findings, transurethral resection of the bladder lesions was\nperformed, achieving near-complete resection (Figure \n4\n).\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n3\n of \n8\n\nFIGURE\n 4: Intraoperative cystoscopic view during transurethral\nresection of the bladder lesions.\nDuring the same treatment episode, the patient underwent laparoscopic drainage of the hematometra and\npartial excision of the rudimentary horn (Figure \n5\n). Complete excision of the horn was not performed\nbecause of extensive adhesions and technical difficulty. The excised rudimentary horn was not submitted for\nhistopathological examination.\nFIGURE\n 5: Intraoperative laparoscopic view following drainage of the\nhematometra and partial excision of the rudimentary uterine horn.\nHistopathological examination of the resected bladder tissue confirmed bladder endometriosis (Figure \n6\n).\nPostoperatively, the patient received leuprolide acetate 11.25 mg intramuscularly every three months for a\ntotal of six months.\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n4\n of \n8\n\nFIGURE\n 6: Histopathological examination of the resected bladder lesion\ndemonstrating endometrial tissue, confirming bladder endometriosis.\nAt the six-month follow-up, the patient was asymptomatic. Repeat ultrasonography, cystoscopy, and\nurinalysis were normal, with no evidence of recurrent bladder lesions on cystoscopy. Follow-up MRI was not\nperformed. The patient expressed a desire to attempt conception at a later date; therefore, no subsequent\nfertility outcome was available at the time of follow-up (Table \n1\n).\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n5\n of \n8\n\nStage\nClinical event\nApproximately one year before\npresentation\nOnset of dysuria, hematuria, and dyspareunia, with worsening during menstruation\nInitial evaluation\nUrinalysis, urine culture, and abdominal ultrasonography\nFurther evaluation\nPelvic MRI demonstrating the uterine anomaly, hematometra, and infiltrative vesicouterine lesion\nDiagnostic evaluation\nCystoscopy demonstrating multiple bladder lesions\nSurgical management\nNear-complete transurethral resection of the bladder lesions, laparoscopic drainage of hematometra, and\npartial excision of the rudimentary horn\nPostoperative management\nLeuprolide acetate initiated\nSix-month follow-up\nPatient remained symptom-free\nTABLE\n 1: Clinical timeline of presentation, diagnostic evaluation, treatment, and follow-up.\nDiscussion\nUrinary tract endometriosis is an uncommon manifestation of endometriosis, with the urinary bladder being\nthe most frequently affected site \n[1,2]\n. Clinical manifestations include dysuria, urinary frequency, urgency,\nsuprapubic or pelvic pain, and hematuria. Symptoms may be cyclical or noncyclical, and the absence of a\nclear temporal relationship with menstruation can contribute to diagnostic delay \n[1,2]\n. Cyclical hematuria is\na characteristic manifestation of bladder endometriosis but occurs in only a minority of affected patients.\nRecognizing a menstrual association with urinary symptoms is therefore clinically important. In the present\ncase, dysuria and hematuria occurred throughout the menstrual cycle but worsened during menstruation,\naccompanied by dyspareunia and dysmenorrhea. The initial urinalysis was unremarkable, and urine culture\nshowed no bacterial growth. These findings, together with the imaging abnormalities, supported further\nevaluation for a noninfectious cause of the urinary symptoms.\nBladder endometriosis commonly involves the posterior bladder wall and base and may extend into the\ndetrusor muscle. Lesions may appear as nodular or infiltrative abnormalities containing hemorrhagic\ncomponents. Magnetic resonance imaging (MRI) is particularly useful for characterizing these lesions,\ndefining their relationship with adjacent pelvic structures, and planning treatment \n[3]\n. In this patient, MRI\ndemonstrated an ill-defined T2-hypointense lesion containing T1-hyperintense foci, centered in the\nvesicouterine pouch and extending posteriorly towards the lower uterine segment and cervix and anteriorly\ninto the bladder wall and lumen. Thickening of the proximal portions of both round ligaments further\nsupported the radiological impression of deep pelvic endometriosis. Ultrasonography had initially identified\nmultiple small bladder masses and the associated uterine anomaly, while MRI provided more detailed\nanatomical characterization of the pelvic disease.\nThe MRI also demonstrated a right-sided hemi-uterus and a separate noncommunicating left-sided cavity\ncontaining hematometra. A unicornuate uterus results from incomplete development of one Müllerian duct\nand may be associated with a rudimentary horn. The European Society of Human Reproduction and\nEmbryology (ESHRE)/European Society for Gynaecological Endoscopy (ESGE) classification categorizes a\nunicornuate uterus as a hemi-uterus \n[4]\n. When a functional rudimentary horn does not communicate with\nthe main uterine cavity, menstrual blood may accumulate within it, resulting in hematometra. This may\ncause dysmenorrhea and chronic pelvic pain and may be associated with endometriosis and reproductive\ndifficulties \n[5]\n. In the present case, the noncommunicating cavity containing hematometra was identified on\nMRI and subsequently treated surgically.\nThe coexistence of a noncommunicating rudimentary horn, hematometra, and endometriosis raises the\npossibility of an association between obstructed menstrual outflow and the development of endometriosis.\nRetrograde menstruation is one proposed mechanism by which menstrual material may reach the peritoneal\ncavity and contribute to endometriotic implantation \n[5]\n. However, the mechanism underlying the\ncoexistence of these abnormalities cannot be established from an individual case, and the presence of\nhematometra does not by itself demonstrate that it caused the bladder endometriosis.\nA particularly relevant report by Giampaolino et al. described a patient with a unicornuate uterus, a\nnoncommunicating rudimentary horn containing hematometra, and a communicating bladder\nendometriotic nodule \n[6]\n. That patient presented with dysmenorrhea, cyclical dysuria, hematuria, and\ninfertility. The report illustrates the potential coexistence of obstructive Müllerian anatomy and bladder\nendometriosis. In the present case, MRI demonstrated a relatively extensive infiltrative lesion centered in\nthe vesicouterine pouch, with extension into the lower uterine segment and cervix and through the bladder\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n6\n of \n8\n\nwall into the bladder lumen. Cystoscopy revealed multiple reddish-brown cystic lesions predominantly\ninvolving the lateral and posterior bladder walls. Histopathological examination of the resected bladder\ntissue confirmed endometriosis. The multifocal bladder involvement and the need for near-complete\ntransurethral resection distinguish the clinical presentation from the previously reported case involving a\nsolitary communicating bladder nodule.\nCystoscopy provides direct visualization of bladder lesions and permits tissue sampling for histopathological\ndiagnosis. Endometriotic lesions may appear bluish, reddish, or brown because of associated hemorrhagic\ncomponents \n[2,3]\n. In this patient, cystoscopy demonstrated multiple reddish-brown cystic lesions, and\nhistopathological examination confirmed bladder endometriosis. Near-complete transurethral resection was\nperformed, with no visible residual lesions documented at the end of the procedure. The agreement between\nthe clinical presentation, MRI findings, cystoscopic appearance, and histopathological diagnosis supported\nthe final diagnosis.\nTreatment of bladder endometriosis should be individualized according to symptom severity, lesion location\nand depth, associated pelvic disease, and reproductive goals. Hormonal treatment may suppress\nendometriotic activity and improve symptoms, whereas surgery may be indicated when symptoms are\nsignificant, lesions require histopathological diagnosis, or anatomical involvement warrants intervention\n[1,2,7]\n. Surgical approaches include transurethral resection in selected cases and more extensive excisional\nprocedures, such as partial cystectomy, depending on the location and depth of disease \n[2,7]\n. Management\nof a symptomatic, functional, noncommunicating rudimentary horn generally involves surgical treatment,\nparticularly when hematometra or associated endometriosis is present \n[5]\n.\nIn the present case, near-complete transurethral resection of the bladder lesions was combined with\nlaparoscopic drainage of the hematometra and partial excision of the rudimentary horn. Complete excision\nof the horn was not feasible because of adhesions and technical difficulty. The horn was not submitted for\nhistopathological examination; therefore, no histological conclusions can be drawn regarding that structure.\nPostoperatively, the patient received leuprolide acetate at a dose of 11.25 mg every three months for six\nmonths. At the six-month follow-up, she was asymptomatic, and ultrasonography, cystoscopy, and\nurinalysis were normal. These findings indicate a favorable short-term clinical outcome. However, no\nfollow-up MRI was performed, and the absence of symptoms and normal cystoscopy do not establish\ncomplete resolution of extravesical endometriotic disease. The patient planned to attempt conception at a\nlater date, so a subsequent fertility outcome was not available.\nThis report has several limitations. As a single case, it cannot establish a causal relationship between the\nMüllerian anomaly, hematometra, and bladder endometriosis. The rudimentary horn was not submitted for\nhistopathological examination, and follow-up MRI was not performed. Although the patient remained\nasymptomatic with normal ultrasonography, cystoscopy, and urinalysis at six months, the limited follow-up\nperiod prevents conclusions regarding long-term recurrence, persistence of extravesical disease, or\nsubsequent fertility outcomes.\nThis case highlights the importance of considering bladder endometriosis in young women presenting with\nurinary symptoms that worsen during menstruation, particularly when initial urine investigations do not\nsupport infection. The presence of a Müllerian anomaly with hematometra should prompt careful\nassessment for associated pelvic endometriosis. Ultrasonography may identify the initial anatomical\nabnormalities, while MRI provides more detailed mapping of the uterine anomaly and the extent of pelvic\ndisease. Cystoscopy and histopathological examination can establish the diagnosis of bladder involvement.\nCoordinated urological and gynecological management can address both urinary tract disease and the\nassociated Müllerian anomaly while taking into account the patient's reproductive plans.\nConclusions\nBladder endometriosis should be considered in young women presenting with cyclical urinary symptoms,\nparticularly when associated with dysmenorrhea and dyspareunia. A unicornuate uterus with a functional\nnoncommunicating rudimentary horn may be complicated by hematometra and associated endometriosis.\nMRI is valuable for delineating the Müllerian anomaly, characterizing hematometra, and mapping the extent\nof deep pelvic and bladder endometriosis. Cystoscopy and histopathological examination provide important\nconfirmation of bladder involvement. A coordinated urological and gynecological approach combining\nsurgical treatment with postoperative hormonal suppression can achieve effective symptom control in\nselected patients.\nAdditional Information\nAuthor Contributions\nAll authors have reviewed the final version to be published and agreed to be accountable for all aspects of the\nwork.\nConcept and design:\n  \nPranesh K. Kumar, Vamshi C. Yadav, Davneet Singh, Jagadeeshwar Thirukovela,\n \n2026 Kumar et al. Cureus 18(10): e117835. DOI 10.7759/cureus.117835\n7\n of \n8\n\nPanduranga Rao Karnam\nAcquisition, analysis, or interpretation of data:\n  \nPranesh K. Kumar, Vamshi C. Yadav, Davneet Singh,\nJagadeeshwar Thirukovela, Panduranga Rao Karnam\nDrafting of the manuscript:\n  \nPranesh K. Kumar, Vamshi C. Yadav, Davneet Singh, Jagadeeshwar\nThirukovela, Panduranga Rao Karnam\nCritical review of the manuscript for important intellectual content:\n  \nPranesh K. Kumar, Vamshi C.\nYadav, Davneet Singh, Jagadeeshwar Thirukovela, Panduranga Rao Karnam\nSupervision:\n  \nPranesh K. Kumar, Vamshi C. Yadav, Davneet Singh, Jagadeeshwar Thirukovela, Panduranga\nRao Karnam\nDisclosures\nHuman subjects:\n Informed consent for treatment and open access publication was obtained or waived by all\nparticipants in this study. \nConflicts of interest:\n In compliance with the ICMJE uniform disclosure form, all\nauthors declare the following: \nPayment/services info:\n All authors have declared that no financial support\nwas received from any organization for the submitted work. \nFinancial relationships:\n All authors have\ndeclared that they have no financial relationships at present or within the previous three years with any\norganizations that might have an interest in the submitted work. \nOther relationships:\n All authors have\ndeclared that there are no other relationships or activities that could appear to have influenced the\nsubmitted work.\nAcknowledgements\nChatGPT (OpenAI) was used during the preparation of this manuscript for language editing, refinement of\nwording, organization of the manuscript, and assistance with literature-related drafting. The authors\nindependently reviewed and verified the content, references, clinical information, and final manuscript and\ntake full responsibility for the accuracy and integrity of the submitted work.\nReferences\n1\n. \nSherman AK, MacLachlan LS: \nA review of urinary tract endometriosis\n. Curr Urol Rep. 2022, 23:219-23.\n10.1007/s11934-022-01107-8\n2\n. \nFleischer K, Bachi A, Kam J, Narayanan P, Nair R, Khazali S: \nBladder endometriosis: what do we know and\nwhat is left to find out? A narrative review\n. Best Pract Res Clin Obstet Gynaecol. 2024, 96:102536.\n10.1016/j.bpobgyn.2024.102536\n3\n. \nShenoy-Bhangle AS, Pires Franco I, Ray LJ, Cao J, Kilcoyne A, Horvat N, Chamie LP: \nImaging of urinary\nbladder and ureteral endometriosis with emphasis on diagnosis and technique\n. 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DOI 10.7759/cureus.117835\n8\n of \n8","source_license":"CC0","license_restricted":false}