Inner Myometrial Laceration Complicated by Severe Antepartum Haemorrhage: A Case Report and Literature Review

Inner Myometrial Laceration Complicated by Severe Antepartum Haemorrhage: A Case Report and Literature Review | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Inner Myometrial Laceration Complicated by Severe Antepartum Haemorrhage: A Case Report and Literature Review Yin Wang, Dehong Liu, Xiumei Wu, Xianxia Chen This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7493159/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Nov, 2025 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted 12 You are reading this latest preprint version Abstract Background Inner myometrial laceration (IML) is a rare but potentially life-threatening obstetric emergency that can cause severe antepartum or postpartum haemorrhage. The pathogenesis of this condition is not fully understood, and this condition is often associated with abnormal uterine contractions, foetal position factors, or obstetric interventions. Its clinical manifestations are nonspecific, making early diagnosis difficult and leading to potential misdiagnosis or missed diagnosis. Case Presentation : This report describes a 26-year-old primigravida at 38⁺¹ weeks gestation who underwent oxytocin induction for preeclampsia. During induction, she presented with sudden massive vaginal haemorrhage, with an estimated blood loss of approximately 1200 ml. An emergency caesarean section revealed a 4 cm inner myometrial laceration on the posterior wall of the lower uterine segment, with the serosal layer intact. Haemostasis was successfully achieved using a "figure-of-8" suture combined with a continuous suture, supplemented with bilateral ligation of the ascending branches of the uterine arteries. The patient recovered well postoperatively, with no complications during follow-up, and her uterus was preserved. Conclusion IML is an important and occult cause of refractory antepartum or postpartum haemorrhage. Diagnosis relies on careful intraoperative exploration. Individualized suturing techniques and necessary vascular ligation are key to preserving fertility, whereas hysterectomy should be reserved as a last resort when conservative measures fail. Enhancing clinical vigilance for IML, early surgical exploration, and targeted repair is crucial for improving maternal and foetal outcomes. Inner myometrial laceration Antepartum haemorrhage Refractory haemorrhage Caesarean section Intraoperative diagnosis Primary suture Figures Figure 1 Figure 2 Figure 3 Introduction Postpartum haemorrhage (PPH) is among the leading causes of maternal mortality worldwide, and antepartum haemorrhage (APH) also seriously threatens maternal and foetal safety [ 1 ]. In addition to maternal coagulation disorders, vaginal and cervical lacerations, uterine rupture, placental abruption, and placenta previa [ 2 ], inner myometrial laceration (IML)—a rare and occult cause of both antepartum and postpartum haemorrhage—is gradually gaining clinical attention [ 3 ]. IML specifically refers to pathological injury in which the endometrium and part of the myometrium are torn but the serosal layer remains intact. Its occurrence is often related to factors such as excessive uterine contractions, abnormal foetal position, or the use of oxytocic drugs [ 4 ]. Since Hayashi et al. [ 5 ] first systematically described it in 2000, only sporadic case reports have been published globally. Owing to the lack of specific clinical manifestations, preoperative diagnosis is extremely difficult; most cases are diagnosed during a caesarean section or via pathological examination after hysterectomy performed for refractory haemorrhage [ 4 ]. Therefore, improving awareness of IML, early recognition, and timely surgical intervention are highly important for reducing hysterectomies and preserving patient fertility. This article reports a case of antepartum haemorrhage caused by IML and presents a review of the literature to explore the clinical features and diagnostic aspects of this condition, as well as management strategies, providing reference information for clinical prevention and treatment. Case presentation The patient was a 26-year-old primigravida at 38 + 1 weeks gestation, admitted to the hospital for planned delivery because of preeclampsia. She had no history of uterine surgery. She had 11 regular prenatal check-ups during pregnancy. At 37 + 6 weeks, her blood pressure was 138/95 mm Hg, 24-hour urinary protein excretion was 460 mg, and other prenatal tests were normal. An examination at admission revealed a blood pressure of 138/100 mm Hg, a heart rate of 89 beats/min, and a temperature of 36.5°C. Laboratory tests revealed a haemoglobin concentration of 123 g/L, a platelet count of 179×10⁹/L, coagulation function (PT of 11.1 s, APTT of 26.6 s, and fibrinogen concentration of 4.14 g/L) and liver and kidney function (ALT concentration of 20 U/L and Cr concentration of 40.9 µmol/L) within the normal range. The cervical Bishop score on admission was 6. Intravenous oxytocin induction was initiated, which failed on the first day. On the second day, she was sent to the delivery room again for intravenous oxytocin induction. At 10:15, a 1% oxytocin infusion was started with continuous foetal heart monitoring (Fig. 1 ). At 15:56, the patient complained of vaginal fluid leakage. Examination revealed massive vaginal bleeding. After routine disinfection, a vaginal examination was performed: the cervix was not dilated, the cervical canal length was 0.5 cm, the cervix was soft, the presenting part was vertex at station − 2, and the membranes were intact. The instantaneous vaginal blood loss was approximately 1200 ml and was bright red. Oxytocin was immediately stopped. An emergency caesarean section under general anaesthesia was performed in the delivery room operating theatre. A transverse lower abdominal incision was made. The uterus was opened via a transverse incision in the lower uterine segment. Clear amniotic fluid, approximately 500 ml, was noted. The placenta was located on the fundal posterior wall, with no signs of abruption or accreta. Twenty units of oxytocin were injected into the uterine body. The placenta separated completely and spontaneously after 1 minute. At this time, the uterine body contracted well, but copious amounts of bright red blood gushed from the lower uterine segment. After the lower uterine segment was packed with large gauze pads and the abdominal incision was covered with wet gauze, the patient was placed in the lithotomy position. Exploration with a vaginal speculum revealed no active bleeding; examination revealed no lacerations in the vagina or cervix. Upon re-exploration in the abdomen, there was no haemoperitoneum, and the uterine body was well contracted. When the large gauze pressure pad covering the lower uterine segment was removed, bright red blood immediately spurted out. The uterus was delivered out of the pelvic cavity. Careful examination revealed a longitudinal inner myometrial laceration at the 6 o'clock position on the posterior wall of the lower uterine segment, approximately 4 cm long, extending 2/3 through the myometrial thickness, with the serosal layer intact (Fig. 2 ). A 1–0 absorbable suture (Vicryl) was used to first place a "figure-of-8" suture at the base of the laceration, followed by a continuous suture to reinforce the muscle layer. Bilateral ligation of the ascending branches of the uterine arteries was also performed simultaneously, without uterine packing. Intraoperative blood loss was 400 ml, totalling 1600 ml pre- and intraoperatively. Postoperative monitoring revealed that the haemoglobin concentration decreased to 77 g/L. Given that the patient was haemodynamically stable with no signs of continued bleeding, transfusion was not administered. The patient recovered well and was discharged 72 hours post-operatively. One-week follow-up revealed that the patient had no complaints of abnormal vaginal bleeding or other discomfort. Ultrasound revealed a well-healed uterine scar, a continuous and intact myometrium, and no abnormal blood flow signals (Fig. 3 ). Discussion In 2000, Hayashi et al. [ 5 ] reported IML in three patients with postpartum haemorrhage that was refractory to conventional uterine atony treatment. Based on observations of hysterectomy specimens, a hypothetical uterine corpus model, and data from 34 women, they proposed IML as a new cause of postpartum haemorrhage, suggesting that it results from excessive stress on the cervix due to abnormally high intrauterine pressure during delivery. In 2016, Kaplanoglu et al. [ 4 ] first explicitly listed IML as a cause of antepartum haemorrhage based on four patients who bled during the active phase of labour and were diagnosed with IML via uterine incision during caesarean section after other causes of bleeding were excluded. In 2024, Khakifirooz et al. [ 6 ] reported a rare case of massive intrapartum haemorrhage in which the patient survived because of timely diagnosis and management of a myometrial laceration. This patient was a 26-year-old primigravida admitted at term with premature rupture of membranes and vaginal bleeding. During spontaneous labour without oxytocin, the estimated blood loss reached 750 ml at 5 cm of cervical dilation. An emergency caesarean section revealed a 4 cm longitudinal laceration in the inner layer of the myometrium on the posterior wall of the lower uterine segment. Haemostasis was achieved with a continuous locked absorbable suture, and the patient recovered well. The case discussed in the present report represents the third report related to IML causing antepartum haemorrhage: a patient at 37 weeks gestation receiving oxytocin induction for preeclampsia who developed sudden antepartum haemorrhage (estimated blood loss of 1200 ml) before cervical dilation, leading to an emergency caesarean section. Intraoperatively, a 4 cm laceration was found within the myometrium of the posterior lower uterine segment (serosa intact), and haemostasis was successfully achieved using absorbable sutures in a "figure-of-8" plus continuous fashion. The patient recovered well postoperatively. Some scholars suggest that IML is an incomplete form of unscarred uterine rupture [ 7 ]. However, significant differences exist between the two: uterine rupture is more common in multiparous women or those with instrumental delivery, whereas IML is more closely associated with augmented contractions when oxytocin is used [ 8 ]. Furthermore, all reported IML cases are confined to the lower uterine segment, whereas approximately 10% of unscarred uterine ruptures occur in the upper uterine segment [ 9 ]. The incidence of IML remains unclear. Since the diagnosis can be confirmed only by direct examination of hysterectomy specimens or via a uterine incision, cases may be missed. Additionally, some minor lacerations might have been successfully managed with uterine packing [ 8 ]. The pathogenesis of inner myometrial laceration (IML) has not been fully elucidated. Among previously reported cases with clearly documented laceration sites, approximately 80% occurred on the posterior uterine wall [ 8 ]. This predilection for the posterior wall and lateral walls of the lower uterine segment suggests that the abnormal distribution of intrauterine pressure might be one injury mechanism [ 5 ]. Furthermore, most cases are associated with the use of oxytocic drugs or augmented contractions, indicating that the occurrence of IML may be linked to abnormal contraction patterns or obstetric interventions [ 8 ]. The case reported in this article involves a patient admitted for preeclampsia who underwent oxytocin-induced labor. Before the occurrence of antepartum hemorrhage, the patient had exhibited significant signs of uterine hyperstimulation. The primary sign of IML is unexplained massive antepartum or postpartum haemorrhage. The patient may have received potent uterotonics (e.g., oxytocin, carboprost), and although the uterus may feel well contracted on external examination, bright red blood continues to flow heavily from the vagina and responds poorly to medication [ 3 – 8 , 10 , 11 ]. Pain may be present but is typically less severe and less dramatic than in complete uterine rupture. Diagnosing IML involves many challenges. Sudden massive haemorrhage is its hallmark, often manifesting as unprovoked vaginal bleeding during active labour or after placental delivery, with blood loss rapidly reaching over 1000 ml and a poor response to conventional uterotonics (e.g., oxytocin and carboprost) [ 8 ]. Definitive diagnosis relies primarily on intraoperative exploration. After excluding common causes, caesarean section or laparotomy is the gold standard for diagnosing IML. Typical intraoperative findings include: (1) an intact serosal layer, but with a longitudinal laceration in the myometrium, extending up to 2/3 of its depth; and (2) lacerations more commonly located on the posterior and lateral walls, mostly single, though cases with multiple or unspecified sites have been reported [ 4 ]. Although pathological examination can reveal characteristic changes such as muscle fibre breaks with haemorrhage, it is seldom used in emergency settings [ 5 ]. In terms of differential diagnosis, IML must be distinguished from (1) placental abruption, which typically presents with abdominal pain, a rigid abdomen, and ultrasound showing a retroplacental haematoma [ 12 ]; (2) uterine rupture, which presents as a full-thickness tear with intra-abdominal bleeding and often leads to shock [ 13 ]; and (3) cervical laceration, where the cervical wound can be directly observed via vaginal examination [ 14 ]. The management strategy for IML depends on the number and location of lacerations and the severity of bleeding. Commonly reported treatments in the literature include hysterectomy, primary suture, and various combined procedures [ 8 ]. Hysterectomy is often used for multiple or severe lacerations combined with uncontrollable bleeding [ 4 , 5 , 8 , 11 ]; primary suture is commonly used for localized single lacerations [ 4 , 6 , 8 , 11 ], with some cases combined with uterine artery ligation [ 4 ], B-Lynch suture [ 4 , 8 ], Cho compression suture [ 3 ], or internal iliac artery ligation [ 10 ]to enhance haemostasis. With respect to primary suturing techniques, it is recommended to choose the appropriate method based on the injury characteristics: (1) layered suture should be the first choice, using 2–0 or 3–0 absorbable suture (e.g., Vicryl), first placing a "figure-of-8" suture to close the base of the laceration, followed by continuous suturing to reinforce the muscle layer to avoid dead space and reduce rebleeding risk [ 7 ]; (2) if the laceration involves branches of the uterine artery, ligation of the ascending branch of the uterine artery (BUtAL) should be combined to effectively control bleeding [ 8 ]; and (3) for diffuse myometrial injury, compressive suturing techniques such as B-Lynch suture [ 15 ] or Cho square suture can be considered to compress the uterine volume and reduce the blood supply [ 3 ]. (4) All procedures should be performed with the patient in the lithotomy position to allow real-time observation of vaginal bleeding [ 3 , 4 ]. In previous cases where hysterectomy was performed for IML, the diagnosis was often confirmed only by postoperative pathological examination following uncontrollable massive postpartum haemorrhage or haemorrhagic shock. If the possibility of IML is considered early and timely surgical exploration with primary suturing is performed, most patients can achieve successful haemostasis through meticulous suturing, thereby avoiding hysterectomy. The indications for hysterectomy should be strictly limited to the following situations: persistent active bleeding after suturing that threatens the patient's life, or concomitant irreparable uterine rupture and placenta accreta [ 3 ]. Conclusion Inner myometrial laceration (IML) is a rare but important cause of life-threatening antepartum or postpartum haemorrhage. Its occurrence is closely related to abnormal uterine contractions, foetal head pressure, or iatrogenic intervention, particularly in the posterior wall of the lower uterine segment. IML typically presents as sudden, refractory vaginal haemorrhage that responds poorly to conventional uterotonics, with diagnosis requiring intraoperative exploration. Treatment should be individualized based on the extent of the laceration and severity of bleeding. Primary meticulous suturing combined with necessary vascular ligation is key to preserving fertility, whereas hysterectomy should be strictly reserved for failure of conservative treatment or when there is associated irreparable damage. Enhancing the clinical recognition of IML and awareness of intraoperative exploration is recommended to improve prognosis and reduce the risk of hysterectomy. Declarations Ethics approval and consent to participate All necessary measures were taken to preserve the information’s confidentiality. The study was conducted in accordance with the Declaration of Helsinki (2008 version). Consent for publication Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Competing interests The authors declare no competing interests. Funding This study was supported by the "Hefei City Health Commission 2024 Applied Medical Research Project" (Grant No.: Hwk2024zc010). Author Contribution YW contributed to the conception and design. DL and XW contributed to the development of the methodology. YW collected and analyzed the data. YW contributed to the writing, review, and/or revision of the manuscript.XC contributed to administrative, technical, or material support. All authors read and approved the final manuscript. Acknowledgements Not applicable. Data availability Not applicable. References Lord MG, Calderon JA, Ahmadzia HK, Pacheco LD. Emerging technology for early detection and management of postpartum hemorrhage to prevent morbidity. Am J Obstet Gynecol MFM. 2023;5(2s):100742. Dahlke JD, Mendez-Figueroa H, Maggio L, Hauspurg AK, Sperling JD, Chauhan SP, Rouse DJ. Prevention and management of postpartum hemorrhage: a comparison of 4 national guidelines. American journal of obstetrics and gynecology 2015, 213(1):76.e71-76.e10. Conrad LB, Groome LJ, Black DR. Management of Persistent Postpartum Hemorrhage Caused by Inner Myometrial Lacerations. Obstet Gynecol. 2015;126(2):266–9. Kaplanoglu M, Kaplanoglu D, Bulbul M, Dilbaz B. Inner myometrial laceration - an unusual presentation of antepartum and postpartum hemorrhage: case reports and review of the literature. J Matern Fetal Neonatal Med. 2016;29(16):2621–4. Hayashi M, Mori Y, Nogami K, Takagi Y, Yaoi M, Ohkura T. A hypothesis to explain the occurence of inner myometrial laceration causing massive postpartum hemorrhage. Acta Obstet Gynecol Scand. 2000;79(2):99–106. Khakifirooz B, Shojaei A, Hajialigol A. A rare case of massive intrapartum hemorrhage followed by inner myometrial laceration during a vaginal delivery: A case report. Clin Case Rep. 2024;12(1):e8373. Page AS, Page G. Letter to 'Inner myometrial laceration: Case report and literature review'. J Obstet Gynaecol Res. 2020;46(12):2701. Zakaria ZA, Mohammad Razin NS, Abas S. Inner myometrial laceration: Case report and literature review. J Obstet Gynaecol Res. 2020;46(11):2442–5. Ofir K, Sheiner E, Levy A, Katz M, Mazor M. Uterine rupture: differences between a scarred and an unscarred uterus. Am J Obstet Gynecol. 2004;191(2):425–9. Pourali L, Ayati S, Vatanchi A, Darvish A. Massive Postpartum Hemorrhage Following an Inner Myometrial Laceration: A Case Report. J Obstet Gynecol Cancer Res 2019. Abu-Rustum RS, Abu-Rustum SE, Abdo BK, Jamal MH. Inner myometrial laceration causing a massive postpartum hemorrhage: a case report. J Reprod Med. 2006;51(2):135–7. Brandt JS, Ananth CV. Placental abruption at near-term and term gestations: pathophysiology, epidemiology, diagnosis, and management. Am J Obstet Gynecol. 2023;228(5s):S1313–29. Takahashi T, Ota K, Jimbo M, Mizunuma H. Spontaneous unscarred uterine rupture and surgical repair at 11 weeks of gestation in a twin pregnancy. J Obstet Gynaecol Res. 2020;46(9):1911–5. Landy HJ, Laughon SK, Bailit JL, Kominiarek MA, Gonzalez-Quintero VH, Ramirez M, Haberman S, Hibbard J, Wilkins I, Branch DW, et al. Characteristics associated with severe perineal and cervical lacerations during vaginal delivery. Obstet Gynecol. 2011;117(3):627–35. C BL, Coker A, Lawal AH, Abu J, Cowen MJ. The B-Lynch surgical technique for the control of massive postpartum haemorrhage: an alternative to hysterectomy? Five cases reported. Br J Obstet Gynaecol. 1997;104(3):372–5. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 10 Nov, 2025 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted Editorial decision: Revision requested 25 Sep, 2025 Reviews received at journal 23 Sep, 2025 Reviewers agreed at journal 17 Sep, 2025 Reviews received at journal 14 Sep, 2025 Reviewers agreed at journal 09 Sep, 2025 Reviews received at journal 09 Sep, 2025 Reviewers agreed at journal 09 Sep, 2025 Reviewers invited by journal 09 Sep, 2025 Editor invited by journal 01 Sep, 2025 Editor assigned by journal 01 Sep, 2025 Submission checks completed at journal 01 Sep, 2025 First submitted to journal 30 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7493159","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":514924517,"identity":"595266bc-f138-48b5-add8-edc5ce703b27","order_by":0,"name":"Yin Wang","email":"","orcid":"","institution":"Maternal and Child Medical Center of Anhui Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yin","middleName":"","lastName":"Wang","suffix":""},{"id":514924518,"identity":"2c4035de-54d4-42bd-bb62-bd0eb0ca368f","order_by":1,"name":"Dehong Liu","email":"","orcid":"","institution":"Maternal and Child Medical Center of Anhui Medical University","correspondingAuthor":false,"prefix":"","firstName":"Dehong","middleName":"","lastName":"Liu","suffix":""},{"id":514924519,"identity":"bd18c9ea-b59b-4258-8861-5313fcaa0ca3","order_by":2,"name":"Xiumei Wu","email":"","orcid":"","institution":"Maternal and Child Medical Center of Anhui Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xiumei","middleName":"","lastName":"Wu","suffix":""},{"id":514924520,"identity":"a8896b78-fa50-407f-9cc7-e9b13f393167","order_by":3,"name":"Xianxia Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwElEQVRIiWNgGAWjYDACCTBZI8fG3sDATIqWY8Z8PAdI08KcOE8igUgt/LObjz3mbWNLbJN8/vBxYRuDPL/YAQKW3DmWbjjjjIxxm3SOsfHMNgbDmbMT8GsxkMgxk/hQwSYL1MImzdvGkGBwm6CW/G8SCQbMjG2Sx58RqyWHDWgLs2KbBIMZcVokbqSZSc44c8yYjQfoF55zEoT9wj8jGeSeGjn59uMPH/OU2cjzSxPQgmEracpHwSgYBaNgFGAHAOJ7OJ5EYOW3AAAAAElFTkSuQmCC","orcid":"","institution":"Maternal and Child Medical Center of Anhui Medical University","correspondingAuthor":true,"prefix":"","firstName":"Xianxia","middleName":"","lastName":"Chen","suffix":""}],"badges":[],"createdAt":"2025-08-30 06:23:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7493159/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7493159/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12884-025-08382-6","type":"published","date":"2025-11-10T15:57:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":91560443,"identity":"67ec75c4-f4f2-4542-9f88-641e32d43300","added_by":"auto","created_at":"2025-09-17 18:42:29","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":692003,"visible":true,"origin":"","legend":"\u003cp\u003eContinuous foetal heart monitoring tracing during oxytocin infusion.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7493159/v1/36c5bff8500992e8e5269b46.jpeg"},{"id":91560446,"identity":"1d179119-fe0c-487e-ae59-6ff3f5de6bd3","added_by":"auto","created_at":"2025-09-17 18:42:29","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":686971,"visible":true,"origin":"","legend":"\u003cp\u003eIntraoperative view of the myometrial laceration on the posterior wall of the lower uterine segment (arrows indicate the extent of the laceration); the serosal layer is intact.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7493159/v1/0457790f35b03721fc745108.jpeg"},{"id":91560440,"identity":"2f7f4b7f-af0b-4717-94c0-1f7a682766cf","added_by":"auto","created_at":"2025-09-17 18:42:29","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":26149,"visible":true,"origin":"","legend":"\u003cp\u003eOne-week post-operative ultrasound image showing a well-healed uterine scar and a continuous and intact myometrium.\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7493159/v1/d2c48aad520708e02a17b8be.jpg"},{"id":96104977,"identity":"c89e59e5-9ef8-4acc-9750-e79f5384a237","added_by":"auto","created_at":"2025-11-17 16:05:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1783406,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7493159/v1/5938ab7b-045b-4b85-9d14-68d4cddc7ece.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Inner Myometrial Laceration Complicated by Severe Antepartum Haemorrhage: A Case Report and Literature Review","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePostpartum haemorrhage (PPH) is among the leading causes of maternal mortality worldwide, and antepartum haemorrhage (APH) also seriously threatens maternal and foetal safety [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. In addition to maternal coagulation disorders, vaginal and cervical lacerations, uterine rupture, placental abruption, and placenta previa [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], inner myometrial laceration (IML)\u0026mdash;a rare and occult cause of both antepartum and postpartum haemorrhage\u0026mdash;is gradually gaining clinical attention [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. IML specifically refers to pathological injury in which the endometrium and part of the myometrium are torn but the serosal layer remains intact. Its occurrence is often related to factors such as excessive uterine contractions, abnormal foetal position, or the use of oxytocic drugs [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Since Hayashi et al. [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] first systematically described it in 2000, only sporadic case reports have been published globally. Owing to the lack of specific clinical manifestations, preoperative diagnosis is extremely difficult; most cases are diagnosed during a caesarean section or via pathological examination after hysterectomy performed for refractory haemorrhage [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Therefore, improving awareness of IML, early recognition, and timely surgical intervention are highly important for reducing hysterectomies and preserving patient fertility. This article reports a case of antepartum haemorrhage caused by IML and presents a review of the literature to explore the clinical features and diagnostic aspects of this condition, as well as management strategies, providing reference information for clinical prevention and treatment.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eThe patient was a 26-year-old primigravida at 38\u0026thinsp;+\u0026thinsp;1 weeks gestation, admitted to the hospital for planned delivery because of preeclampsia. She had no history of uterine surgery. She had 11 regular prenatal check-ups during pregnancy. At 37\u0026thinsp;+\u0026thinsp;6 weeks, her blood pressure was 138/95 mm Hg, 24-hour urinary protein excretion was 460 mg, and other prenatal tests were normal. An examination at admission revealed a blood pressure of 138/100 mm Hg, a heart rate of 89 beats/min, and a temperature of 36.5\u0026deg;C. Laboratory tests revealed a haemoglobin concentration of 123 g/L, a platelet count of 179\u0026times;10⁹/L, coagulation function (PT of 11.1 s, APTT of 26.6 s, and fibrinogen concentration of 4.14 g/L) and liver and kidney function (ALT concentration of 20 U/L and Cr concentration of 40.9 \u0026micro;mol/L) within the normal range.\u003c/p\u003e\u003cp\u003eThe cervical Bishop score on admission was 6. Intravenous oxytocin induction was initiated, which failed on the first day. On the second day, she was sent to the delivery room again for intravenous oxytocin induction. At 10:15, a 1% oxytocin infusion was started with continuous foetal heart monitoring (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). At 15:56, the patient complained of vaginal fluid leakage. Examination revealed massive vaginal bleeding. After routine disinfection, a vaginal examination was performed: the cervix was not dilated, the cervical canal length was 0.5 cm, the cervix was soft, the presenting part was vertex at station \u0026minus;\u0026thinsp;2, and the membranes were intact. The instantaneous vaginal blood loss was approximately 1200 ml and was bright red. Oxytocin was immediately stopped. An emergency caesarean section under general anaesthesia was performed in the delivery room operating theatre.\u003c/p\u003e\u003cp\u003eA transverse lower abdominal incision was made. The uterus was opened via a transverse incision in the lower uterine segment. Clear amniotic fluid, approximately 500 ml, was noted. The placenta was located on the fundal posterior wall, with no signs of abruption or accreta. Twenty units of oxytocin were injected into the uterine body. The placenta separated completely and spontaneously after 1 minute. At this time, the uterine body contracted well, but copious amounts of bright red blood gushed from the lower uterine segment. After the lower uterine segment was packed with large gauze pads and the abdominal incision was covered with wet gauze, the patient was placed in the lithotomy position. Exploration with a vaginal speculum revealed no active bleeding; examination revealed no lacerations in the vagina or cervix. Upon re-exploration in the abdomen, there was no haemoperitoneum, and the uterine body was well contracted. When the large gauze pressure pad covering the lower uterine segment was removed, bright red blood immediately spurted out. The uterus was delivered out of the pelvic cavity. Careful examination revealed a longitudinal inner myometrial laceration at the 6 o'clock position on the posterior wall of the lower uterine segment, approximately 4 cm long, extending 2/3 through the myometrial thickness, with the serosal layer intact (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eA 1\u0026ndash;0 absorbable suture (Vicryl) was used to first place a \"figure-of-8\" suture at the base of the laceration, followed by a continuous suture to reinforce the muscle layer. Bilateral ligation of the ascending branches of the uterine arteries was also performed simultaneously, without uterine packing. Intraoperative blood loss was 400 ml, totalling 1600 ml pre- and intraoperatively. Postoperative monitoring revealed that the haemoglobin concentration decreased to 77 g/L. Given that the patient was haemodynamically stable with no signs of continued bleeding, transfusion was not administered. The patient recovered well and was discharged 72 hours post-operatively. One-week follow-up revealed that the patient had no complaints of abnormal vaginal bleeding or other discomfort. Ultrasound revealed a well-healed uterine scar, a continuous and intact myometrium, and no abnormal blood flow signals (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn 2000, Hayashi et al. [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] reported IML in three patients with postpartum haemorrhage that was refractory to conventional uterine atony treatment. Based on observations of hysterectomy specimens, a hypothetical uterine corpus model, and data from 34 women, they proposed IML as a new cause of postpartum haemorrhage, suggesting that it results from excessive stress on the cervix due to abnormally high intrauterine pressure during delivery. In 2016, Kaplanoglu et al. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e] first explicitly listed IML as a cause of antepartum haemorrhage based on four patients who bled during the active phase of labour and were diagnosed with IML via uterine incision during caesarean section after other causes of bleeding were excluded. In 2024, Khakifirooz et al. [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] reported a rare case of massive intrapartum haemorrhage in which the patient survived because of timely diagnosis and management of a myometrial laceration. This patient was a 26-year-old primigravida admitted at term with premature rupture of membranes and vaginal bleeding. During spontaneous labour without oxytocin, the estimated blood loss reached 750 ml at 5 cm of cervical dilation. An emergency caesarean section revealed a 4 cm longitudinal laceration in the inner layer of the myometrium on the posterior wall of the lower uterine segment. Haemostasis was achieved with a continuous locked absorbable suture, and the patient recovered well.\u003c/p\u003e\u003cp\u003eThe case discussed in the present report represents the third report related to IML causing antepartum haemorrhage: a patient at 37 weeks gestation receiving oxytocin induction for preeclampsia who developed sudden antepartum haemorrhage (estimated blood loss of 1200 ml) before cervical dilation, leading to an emergency caesarean section. Intraoperatively, a 4 cm laceration was found within the myometrium of the posterior lower uterine segment (serosa intact), and haemostasis was successfully achieved using absorbable sutures in a \"figure-of-8\" plus continuous fashion. The patient recovered well postoperatively.\u003c/p\u003e\u003cp\u003eSome scholars suggest that IML is an incomplete form of unscarred uterine rupture [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, significant differences exist between the two: uterine rupture is more common in multiparous women or those with instrumental delivery, whereas IML is more closely associated with augmented contractions when oxytocin is used [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Furthermore, all reported IML cases are confined to the lower uterine segment, whereas approximately 10% of unscarred uterine ruptures occur in the upper uterine segment [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe incidence of IML remains unclear. Since the diagnosis can be confirmed only by direct examination of hysterectomy specimens or via a uterine incision, cases may be missed. Additionally, some minor lacerations might have been successfully managed with uterine packing [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe pathogenesis of inner myometrial laceration (IML) has not been fully elucidated. Among previously reported cases with clearly documented laceration sites, approximately 80% occurred on the posterior uterine wall [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This predilection for the posterior wall and lateral walls of the lower uterine segment suggests that the abnormal distribution of intrauterine pressure might be one injury mechanism [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Furthermore, most cases are associated with the use of oxytocic drugs or augmented contractions, indicating that the occurrence of IML may be linked to abnormal contraction patterns or obstetric interventions [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The case reported in this article involves a patient admitted for preeclampsia who underwent oxytocin-induced labor. Before the occurrence of antepartum hemorrhage, the patient had exhibited significant signs of uterine hyperstimulation.\u003c/p\u003e\u003cp\u003eThe primary sign of IML is unexplained massive antepartum or postpartum haemorrhage. The patient may have received potent uterotonics (e.g., oxytocin, carboprost), and although the uterus may feel well contracted on external examination, bright red blood continues to flow heavily from the vagina and responds poorly to medication [\u003cspan additionalcitationids=\"CR4 CR5 CR6 CR7\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Pain may be present but is typically less severe and less dramatic than in complete uterine rupture.\u003c/p\u003e\u003cp\u003eDiagnosing IML involves many challenges. Sudden massive haemorrhage is its hallmark, often manifesting as unprovoked vaginal bleeding during active labour or after placental delivery, with blood loss rapidly reaching over 1000 ml and a poor response to conventional uterotonics (e.g., oxytocin and carboprost) [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Definitive diagnosis relies primarily on intraoperative exploration. After excluding common causes, caesarean section or laparotomy is the gold standard for diagnosing IML. Typical intraoperative findings include: (1) an intact serosal layer, but with a longitudinal laceration in the myometrium, extending up to 2/3 of its depth; and (2) lacerations more commonly located on the posterior and lateral walls, mostly single, though cases with multiple or unspecified sites have been reported [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Although pathological examination can reveal characteristic changes such as muscle fibre breaks with haemorrhage, it is seldom used in emergency settings [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn terms of differential diagnosis, IML must be distinguished from (1) placental abruption, which typically presents with abdominal pain, a rigid abdomen, and ultrasound showing a retroplacental haematoma [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]; (2) uterine rupture, which presents as a full-thickness tear with intra-abdominal bleeding and often leads to shock [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]; and (3) cervical laceration, where the cervical wound can be directly observed via vaginal examination [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe management strategy for IML depends on the number and location of lacerations and the severity of bleeding. Commonly reported treatments in the literature include hysterectomy, primary suture, and various combined procedures [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Hysterectomy is often used for multiple or severe lacerations combined with uncontrollable bleeding [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]; primary suture is commonly used for localized single lacerations [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], with some cases combined with uterine artery ligation [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], B-Lynch suture [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], Cho compression suture [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], or internal iliac artery ligation [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]to enhance haemostasis.\u003c/p\u003e\u003cp\u003eWith respect to primary suturing techniques, it is recommended to choose the appropriate method based on the injury characteristics: (1) layered suture should be the first choice, using 2\u0026ndash;0 or 3\u0026ndash;0 absorbable suture (e.g., Vicryl), first placing a \"figure-of-8\" suture to close the base of the laceration, followed by continuous suturing to reinforce the muscle layer to avoid dead space and reduce rebleeding risk [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]; (2) if the laceration involves branches of the uterine artery, ligation of the ascending branch of the uterine artery (BUtAL) should be combined to effectively control bleeding [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]; and (3) for diffuse myometrial injury, compressive suturing techniques such as B-Lynch suture [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] or Cho square suture can be considered to compress the uterine volume and reduce the blood supply [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. (4) All procedures should be performed with the patient in the lithotomy position to allow real-time observation of vaginal bleeding [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn previous cases where hysterectomy was performed for IML, the diagnosis was often confirmed only by postoperative pathological examination following uncontrollable massive postpartum haemorrhage or haemorrhagic shock. If the possibility of IML is considered early and timely surgical exploration with primary suturing is performed, most patients can achieve successful haemostasis through meticulous suturing, thereby avoiding hysterectomy. The indications for hysterectomy should be strictly limited to the following situations: persistent active bleeding after suturing that threatens the patient's life, or concomitant irreparable uterine rupture and placenta accreta [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eInner myometrial laceration (IML) is a rare but important cause of life-threatening antepartum or postpartum haemorrhage. Its occurrence is closely related to abnormal uterine contractions, foetal head pressure, or iatrogenic intervention, particularly in the posterior wall of the lower uterine segment. IML typically presents as sudden, refractory vaginal haemorrhage that responds poorly to conventional uterotonics, with diagnosis requiring intraoperative exploration. Treatment should be individualized based on the extent of the laceration and severity of bleeding. Primary meticulous suturing combined with necessary vascular ligation is key to preserving fertility, whereas hysterectomy should be strictly reserved for failure of conservative treatment or when there is associated irreparable damage. Enhancing the clinical recognition of IML and awareness of intraoperative exploration is recommended to improve prognosis and reduce the risk of hysterectomy.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003cp\u003eAll necessary measures were taken to preserve the information\u0026rsquo;s confidentiality. The study was conducted in accordance with the Declaration of Helsinki (2008 version).\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cp\u003e Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eThis study was supported by the \"Hefei City Health Commission 2024 Applied Medical Research Project\" (Grant No.: Hwk2024zc010).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eYW contributed to the conception and design. DL and XW contributed to the development of the methodology. YW collected and analyzed the data. YW contributed to the writing, review, and/or revision of the manuscript.XC contributed to administrative, technical, or material support. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eNot applicable.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLord MG, Calderon JA, Ahmadzia HK, Pacheco LD. Emerging technology for early detection and management of postpartum hemorrhage to prevent morbidity. Am J Obstet Gynecol MFM. 2023;5(2s):100742.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDahlke JD, Mendez-Figueroa H, Maggio L, Hauspurg AK, Sperling JD, Chauhan SP, Rouse DJ. Prevention and management of postpartum hemorrhage: a comparison of 4 national guidelines. \u003cem\u003eAmerican journal of obstetrics and gynecology\u003c/em\u003e 2015, 213(1):76.e71-76.e10.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eConrad LB, Groome LJ, Black DR. Management of Persistent Postpartum Hemorrhage Caused by Inner Myometrial Lacerations. Obstet Gynecol. 2015;126(2):266\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKaplanoglu M, Kaplanoglu D, Bulbul M, Dilbaz B. Inner myometrial laceration - an unusual presentation of antepartum and postpartum hemorrhage: case reports and review of the literature. J Matern Fetal Neonatal Med. 2016;29(16):2621\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHayashi M, Mori Y, Nogami K, Takagi Y, Yaoi M, Ohkura T. A hypothesis to explain the occurence of inner myometrial laceration causing massive postpartum hemorrhage. Acta Obstet Gynecol Scand. 2000;79(2):99\u0026ndash;106.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKhakifirooz B, Shojaei A, Hajialigol A. A rare case of massive intrapartum hemorrhage followed by inner myometrial laceration during a vaginal delivery: A case report. Clin Case Rep. 2024;12(1):e8373.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePage AS, Page G. Letter to 'Inner myometrial laceration: Case report and literature review'. J Obstet Gynaecol Res. 2020;46(12):2701.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZakaria ZA, Mohammad Razin NS, Abas S. Inner myometrial laceration: Case report and literature review. J Obstet Gynaecol Res. 2020;46(11):2442\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOfir K, Sheiner E, Levy A, Katz M, Mazor M. Uterine rupture: differences between a scarred and an unscarred uterus. Am J Obstet Gynecol. 2004;191(2):425\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePourali L, Ayati S, Vatanchi A, Darvish A. Massive Postpartum Hemorrhage Following an Inner Myometrial Laceration: A Case Report. J Obstet Gynecol Cancer Res 2019.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAbu-Rustum RS, Abu-Rustum SE, Abdo BK, Jamal MH. Inner myometrial laceration causing a massive postpartum hemorrhage: a case report. J Reprod Med. 2006;51(2):135\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBrandt JS, Ananth CV. Placental abruption at near-term and term gestations: pathophysiology, epidemiology, diagnosis, and management. Am J Obstet Gynecol. 2023;228(5s):S1313\u0026ndash;29.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTakahashi T, Ota K, Jimbo M, Mizunuma H. Spontaneous unscarred uterine rupture and surgical repair at 11 weeks of gestation in a twin pregnancy. J Obstet Gynaecol Res. 2020;46(9):1911\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLandy HJ, Laughon SK, Bailit JL, Kominiarek MA, Gonzalez-Quintero VH, Ramirez M, Haberman S, Hibbard J, Wilkins I, Branch DW, et al. Characteristics associated with severe perineal and cervical lacerations during vaginal delivery. Obstet Gynecol. 2011;117(3):627\u0026ndash;35.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eC BL, Coker A, Lawal AH, Abu J, Cowen MJ. The B-Lynch surgical technique for the control of massive postpartum haemorrhage: an alternative to hysterectomy? Five cases reported. Br J Obstet Gynaecol. 1997;104(3):372\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Inner myometrial laceration, Antepartum haemorrhage, Refractory haemorrhage, Caesarean section, Intraoperative diagnosis, Primary suture","lastPublishedDoi":"10.21203/rs.3.rs-7493159/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7493159/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eInner myometrial laceration (IML) is a rare but potentially life-threatening obstetric emergency that can cause severe antepartum or postpartum haemorrhage. The pathogenesis of this condition is not fully understood, and this condition is often associated with abnormal uterine contractions, foetal position factors, or obstetric interventions. Its clinical manifestations are nonspecific, making early diagnosis difficult and leading to potential misdiagnosis or missed diagnosis.\u003c/p\u003e\u003ch2\u003eCase Presentation\u003c/h2\u003e\u003cp\u003e: This report describes a 26-year-old primigravida at 38⁺\u0026sup1; weeks gestation who underwent oxytocin induction for preeclampsia. During induction, she presented with sudden massive vaginal haemorrhage, with an estimated blood loss of approximately 1200 ml. An emergency caesarean section revealed a 4 cm inner myometrial laceration on the posterior wall of the lower uterine segment, with the serosal layer intact. Haemostasis was successfully achieved using a \"figure-of-8\" suture combined with a continuous suture, supplemented with bilateral ligation of the ascending branches of the uterine arteries. The patient recovered well postoperatively, with no complications during follow-up, and her uterus was preserved.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eIML is an important and occult cause of refractory antepartum or postpartum haemorrhage. Diagnosis relies on careful intraoperative exploration. Individualized suturing techniques and necessary vascular ligation are key to preserving fertility, whereas hysterectomy should be reserved as a last resort when conservative measures fail. Enhancing clinical vigilance for IML, early surgical exploration, and targeted repair is crucial for improving maternal and foetal outcomes.\u003c/p\u003e","manuscriptTitle":"Inner Myometrial Laceration Complicated by Severe Antepartum Haemorrhage: A Case Report and Literature Review","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-17 18:42:24","doi":"10.21203/rs.3.rs-7493159/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-25T11:31:58+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-23T09:45:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"33957593173730617789151265949052178680","date":"2025-09-17T23:48:11+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-14T22:37:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"294709910599885612748641099491949132560","date":"2025-09-09T21:58:39+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-09T15:43:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"13114111246431493555000668381842688034","date":"2025-09-09T15:39:33+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-09T15:29:53+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-09-01T12:49:10+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-01T07:00:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-01T07:00:01+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pregnancy and Childbirth","date":"2025-08-30T06:11:31+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3271e757-3298-4ea6-bda6-7665e9a48ff8","owner":[],"postedDate":"September 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-17T16:00:00+00:00","versionOfRecord":{"articleIdentity":"rs-7493159","link":"https://doi.org/10.1186/s12884-025-08382-6","journal":{"identity":"bmc-pregnancy-and-childbirth","isVorOnly":false,"title":"BMC Pregnancy and Childbirth"},"publishedOn":"2025-11-10 15:57:00","publishedOnDateReadable":"November 10th, 2025"},"versionCreatedAt":"2025-09-17 18:42:24","video":"","vorDoi":"10.1186/s12884-025-08382-6","vorDoiUrl":"https://doi.org/10.1186/s12884-025-08382-6","workflowStages":[]},"version":"v1","identity":"rs-7493159","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7493159","identity":"rs-7493159","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}