Risk Factors Preceding Uterine Artery Embolization in the Setting of Postpartum Hemorrhage

Risk Factors Preceding Uterine Artery Embolization in the Setting of Postpartum Hemorrhage | 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 Research Article Risk Factors Preceding Uterine Artery Embolization in the Setting of Postpartum Hemorrhage Devin Reddy, Bunnarin Theng, Aparna Medarametla, Haroon Dossani, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7411786/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose Uterine artery embolization (UAE) is a minimally invasive, uterine-sparing intervention that can help control postpartum hemorrhage (PPH) when more conservative management has failed. While risk factors for PPH are well established, those leading to the use of embolization remain unclear. This study aimed to determine how maternal history, pregnancy characteristics, and peripartum events impact the utilization of UAE for PPH in the peripartum period. Materials and Methods This case-control study queried electronic health records from 78 healthcare organizations in the United States for patients with PPH from April 2014 to April 2024. Patients who did and did not undergo UAE were then analyzed for risk factors in the preceding year from their initial event. Results Among 158,741 patients with PPH, 796 underwent UAE (mean age 32.1 ± 6.4 years). Significant risk factors included uterine scar (AR 57.20%), fibroids (AR 57.86%), endometriosis (AR 45.79%), advanced maternal age (AR 43.74%), assisted reproductive technology (AR 59.52%), uterine overdistension (AR 29.17%), placental abnormalities (AR 59.66%), pre-eclampsia (AR 37.56%), cesarean delivery (AR 55.81%), anemia (AR 76.62%), disseminated intravascular coagulation (AR 93.21%), thrombocytopenia (AR 57.39%), and shock (AR 94.46%) (p < 0.05). Other identified factors did not significantly impact UAE use. Conclusion Identifying these critical risk factors can help preemptively identify patients at higher risk of needing UAE and can be used to improve multidisciplinary coordination of care and response times, potentially reducing maternal and neonatal morbidity and mortality. Vascular Medicine Nuclear Medicine & Medical Imaging Uterine artery embolization Postpartum hemorrhage Risk factors Case control study Interventional radiology Figures Figure 1 Figure 2 Introduction Postpartum hemorrhage (PPH) is a severe obstetric complication seen in nearly 10% of deliveries and is responsible for over one quarter of maternal deaths worldwide [ 1 ]. The American College of Obstetricians and Gynecologists (ACOG) define PPH as the cumulative loss of at least 1,000 mL of blood, or blood loss presenting with symptomatic hypovolemia within 24 hours of delivery [ 2 ]. PPH is most commonly attributed to uterine atony, or inadequate uterine contraction after birth resulting in insufficient placental vessel compression [ 1 ]. Risk factors for uterine atony include multiple gestation pregnancy, polyhydramnios, and fetal macrosomia, all of which cause uterine enlargement; pathology that alters the structure of the uterus such as uterine fibroids; and prolonged exposure to medications or infection during the peripartum period such as general anesthesia, oxytocin, or chorioamnionitis. Rarer obstetric complications that increase the risk of PPH include retained products of conception, abnormal placental structure or attachment (e.g., placenta accreta spectrum), trauma to the uterus and birth canal, and coagulopathies that may be inherent or acquired (abruptio placentae, gestational hypertension, amniotic fluid embolism, or anticoagulant use). Antepartum risk factors for developing PPH must also be considered: advanced maternal age, preeclampsia, use of in vitro fertilization or intracytoplasmic sperm injections, and increased body mass index [ 3 ]. PPH has both acute and chronic effects on maternal morbidity and mortality, including but not limited to anemia requiring transfusion, acute respiratory distress syndrome, hypovolemic shock, disseminated intravascular coagulation, acute renal failure, Sheehan syndrome, loss of fertility, and death [ 1 , 2 ]. Due to the severity of these complications, it is imperative that patients at risk for PPH are identified as early as possible and several treatment options exist to mitigate or circumvent the effects of this condition (Fig. 1 ). Though a hysterectomy can be a life-saving procedure in the setting of refractory PPH, this definitive intervention is also associated with substantial morbidity for young mothers. Tsolakidis et al. have previously described the significantly elevated risk of complications in pregnancy-related hysterectomies as compared to non-obstetric hysterectomies [ 6 ]. These complications most commonly include bladder and/or ureteral injury, wound dehiscence, and venous thrombosis. Damage to the pelvic floor muscles may result in incontinence and recurrent urinary tract infections, which can be severely debilitating for young mothers and patients in general. One method of conservative management of PPH that may be considered prior to hysterectomy is uterine artery embolization (UAE). UAE is a minimally invasive procedure conducted by an interventional radiologist (IR) that has the added benefit of preserving the patient’s fertility and decreasing their hospital stay [ 7 , 8 ]. In a national inpatient sample study by Webster et al., PPH patients managed with UAE were 0.38 times less likely to have a prolonged hospital stay compared to patients who received a hysterectomy [ 9 ]. In a systematic review by Sathe et al., 89% of UAE procedures were successful in treating PPH [ 10 ]. Though more commonly used in the treatment of refractory or painful leiomyomas (uterine fibroids), UAE has become an increasingly utilized method of reducing PPH. The techniques for UAE have previously extensively been described in literature by Brown et al. and Ruiz Labarta et al. and will not be explored in this paper. Potential for rebleeding is the most common complication of UAE (albeit low). Other rare complications of UAE include uterine infarction, ovarian insufficiency, endometritis, and abscess formation. Few contraindications exist to UAE, namely hemodynamic instability and uncontrolled coagulopathy. Risk factors for a failed UAE procedure include narrow uterine arteries, disseminated intravascular coagulation (due to decreased clotting power secondary to consumption of clotting factors), cesarean delivery and receiving large volumes of blood transfusion [ 11 , 12 ]. Despite numerous studies providing evidence in favor of employing UAE as a conservative treatment option before considering total hysterectomy, IR continues to be an underutilized service in obstetrics and maternal-fetal medicine and often becomes involved much later in the management of PPH patients, as detailed in Fig. 1 [ 13 ]. In fact, the International Federation of Gynecology and Obstetrics (FIGO) identifies skilled human resources as a limitation for the implementation of this life-saving technique [ 4 ]. Current guidelines call for more evidence regarding the clinical benefits of IR, safety of ionizing radiation exposure, and real-time implementation of UAE procedures in hospitals and by clinicians, which at present appears to be more subjective based on access to IR facilities and physician comfort. The purpose of this study, therefore, is two-fold: to analyze the risk factors for mothers who developed PPH and were treated with UAE, and to stratify these risk factors and identify patients at high risk for PPH who would benefit from an IR consult and subsequent UAE treatment. Materials & Methods The data for this case-control study was sourced from the TriNetX platform and was deemed IRB-exempt via the University of Texas Medical Branch institutional IRB. TriNetX (Cambridge, MA) is a database of anonymized patient CPT and ICD-10 codes from healthcare organizations across the globe. A list of the CPT and ICD-10 codes used in this study can be found in the Supplementary Materials. Within TriNetX, patients who had received the ICD-10 code for PPH (O72) between April 2014 and April 2024 were anonymously identified from 78 healthcare organizations in the United States. Our study population was then divided into two groups, those who underwent UAE within one month of the first instance of PPH (the ‘cases’), and those who did not (the ‘controls’; Supplementary Table 1). Next, the groups were compared on historical factors present in the patient’s chart up to one year before the first instance of the PPH ICD-10 code (Supplementary Table 2). Statistical analysis was performed in the TriNetX database and with Microsoft Excel. The null hypothesis for the analyzed historical factors was no difference between the two groups. For each historical factor, the incidence, risk ratio, and attributable risk percent for each historical variable was calculated. Categorical data (presented as incidence) was analyzed with chi-square tests with an alpha level of 0.05. Risk ratios were reported in this study instead of odds ratios because the incidence for each historical factor was rare (< 10%) in both groups. Results 158,741 patients with PPH were identified during the study period. Of these, 796 patients underwent UAE, while 157,945 did not. The mean age of patients who underwent UAE was 32.1 ± 6.4 years, compared to 29.7 ± 6.6 years for those who did not. Among these patients, many risk factors were identified and grouped into three categories: maternal history, pregnancy characteristics, and peripartum events. Maternal History Patients with history of uterine fibroids demonstrated the highest increased risk for PPH requiring UAE, with a risk ratio (RR) of 2.37 and attributable risk (AR) of 57.86% (p < 0.0001). Comparatively, patients with a history of uterine scars from previous surgery (RR 2.34, AR 57.20%, p < 0.0001) and endometriosis (RR 1.84, AR 45.79%, p = 0.011) were also associated with a significantly increased risk for PPH requiring UAE. The remainder of maternal history, including preterm labor, previous pregnancy complications, chronic or gestational anemia, diabetes mellitus in pregnancy, and obesity did not show any statistically significant associations (Table 1 ). Table 1 Summary of Risk Factors for UAE Utilization in PPH Categories Risk Factors Incidence in UAE (+) (%) Incidence in UAE (-) (%) RR AR (%) p-value Maternal History Uterine Fibroids 1.12 0.47 2.37 57.86 < 0.0001* Uterine Scar from Previous Surgery 0.93 0.40 2.34 57.20 < 0.0001* Endometriosis 0.92 0.50 1.84 45.79 0.011* Diabetes Mellitus in Pregnancy 0.57 0.49 1.17 14.72 0.102 Previous Pregnancy Complications 0.56 0.49 1.14 12.56 0.1179 Chronic/Gestational Anemia 0.51 0.50 1.03 2.54 0.7468 Preterm Labor 0.49 0.50 0.97 N/A 0.8786 Obesity 0.47 0.51 0.92 N/A 0.3004 Pregnancy Characteristics Placental Abnormalities 0.97 0.39 2.48 59.66 < 0.0001* Conception via ART 1.16 0.47 2.47 59.52 < 0.0001* Advanced Maternal Age 0.78 0.44 1.78 43.74 < 0.0001* Pre-Eclampsia 0.73 0.46 1.60 37.56 < 0.0001* Uterine Overdistension 0.67 0.47 1.41 29.17 0.0001* High-Risk Pregnancy 0.53 0.46 1.15 12.85 0.0553 Peripartum Events Shock 7.55 0.42 18.04 94.46 < 0.0001* DIC 6.77 0.46 14.74 93.21 < 0.0001* Acute Anemia 1.29 0.30 4.28 76.62 < 0.0001* Thrombocytopenia 1.09 0.47 2.35 57.39 < 0.0001* Cesarean Delivery 0.84 0.37 2.26 55.81 < 0.0001* Chorioamnionitis 0.57 0.50 1.15 13.07 0.244 Long labor 0.52 0.50 1.04 4.15 0.8665 Preterm Labor 0.39 0.52 0.75 N/A 0.0142* Post-Term Pregnancy 0.37 0.52 0.71 N/A 0.0021* Obstetric Trauma or Laceration 0.35 0.60 0.59 N/A < 0.0001* Vaginal Delivery 0.36 0.72 0.50 N/A < 0.0001* * Indicates statistically significant association Pregnancy Characteristics Placental abnormalities and conception by assisted reproduction technology (ART) were associated with significant risk factors for PPH, with RR of 2.48 and 2.47, AR of 59.66% and 59.52% respectively (p < 0.0001). Advanced maternal age (≥ 35 years) and pre-eclampsia also contributed significantly (RR 1.78 and 1.60 and AR 43.74% and 37.56% respectively) (p < 0.0001). Lastly, uterine overdistension, whether due to multiple gestations or macrosomia, demonstrated a significant association (RR 1.41, AR 29.17%, p < 0.0001) while high-risk pregnancies approached significance but did not meet the threshold (RR 1.15, AR 12.85%, p = 0.0553). Peripartum Events Shock was the most significant peripartum risk factor, with an RR of 18.04 and AR of 94.46% (p < 0.0001), followed by disseminated intravascular coagulation (DIC) with RR 14.74, AR 93.21%, p < 0.0001. Another coagulopathy, thrombocytopenia, is also associated with increased risk (RR 2.35, AR 57.39, p < 0.0001). On the other hand, cesarean delivery was a major peripartum risk factor, with an RR of 2.26 and an AR of 55.81% (p < 0.0001) while vaginal delivery (VD) was associated with relatively decreased risk (RR 0.5, p < 0.0001). Other risk factors, such as preterm labor (RR 0.75, p = 0.0142), post-term labor (RR 0.71, p = 0.0021), and obstetric trauma or laceration (RR 0.59, p < 0.0001) were all significantly associated with decreased risk of UAE utilization. However, chorioamnionitis (RR 1.15, p = 0.244) and long labor (RR 1.04, p = 0.8665) showed limited significant associations. Discussion While the risk factors for postpartum hemorrhage (PPH) have been previously well-established, this study further explores the PPH patients that undergo uterine artery embolization (UAE). Our findings indicate that obesity and preterm labor are associated with minimal reduced risk, while factors such as post-term pregnancy, obstetric trauma or lacerations, and vaginal delivery are significantly linked to a lower risk of PPH. This study also examined additional risk factors such as coagulopathies (shock, DIC, acute anemia, thrombocytopenia), endometriosis, advanced maternal age, which are all associated with significantly increased risk for PPH requiring UAE. This approach highlights the importance of considering less traditionally recognized contributors to hemorrhage. Additionally, understanding these risk factors allows for early identification of patients at higher risk of requiring UAE, guiding earlier intervention strategies. This includes implementing systemic models to enhance monitoring during delivery and establishing protocols that integrate IR teams, either through pre-procedure consultation or standby readiness. Such targeted approaches have been shown to significantly improve outcomes by reducing the likelihood of hysterectomy and minimizing complications [ 8 ]. UAE is increasingly recognized as an effective intervention for refractory PPH. A retrospective study by Akoi et al. found that UAE had a 85% clinical success rate in achieving adequate hemostasis in patients with refractory PPH, offering life-saving outcomes, particularly in cases where surgical interventions may be delayed or contraindicated [ 14 ]. Further benefits of UAE include fertility preservation, shorter hospital stays, and a lower risk profile compared to cesarean hysterectomy. For instance, in a large multicenter study, UAE was associated with a median maternal length of hospital stay of 5 days, a mean intraoperative transfusion of 3.7 units of packed red blood cells (pRBCs), and the morbidity and mortality rates of 1.6% compared to 22 days in the hospital, 4.6 units of pRBCs, and 34.9% mortality rate [ 9 ]. Additionally, cesarean hysterectomy has been shown to pose significant surgical risks. A cross-institutional observational study by Shellhaas et al showed that major maternal complications of cesarean hysterectomy include transfusion of red blood cells (84%) and other blood products (34%), fever (11%), subsequent laparotomy (4%), ureteral injury (3%), and death (1.6%) [ 15 ]. While UAE has been shown to be a safer procedure for controlling hemorrhage with more favorable safety profile compared to surgical alternatives, there are also concerns regarding its potential impact on future fertility, particularly among younger patients who may desire future pregnancies. To this day, the effects of UAE on menstruation and fertility have not been sufficiently addressed and the relationship between the amount of bleeding and the time to embolization and the success of UAE, including fertility and the return of menstruation, are still not well understood [ 16 ]. In addition, studies have shown that prior UAE is a significant risk factor for placenta accreta spectrum and increases the risk of PPH in subsequent pregnancies, requiring close monitoring for potential complications [ 17 ]. Moreover, it was noted that the majority of patients with PPH in this study did not undergo UAE, with only 0.5% did. According to ACOG guidelines, the current PPH management include manual uterine massage and medical interventions with uterotonic agents (eg, oxytocin, methylergonovine, and misoprostol) as the first-line treatment, followed by intrauterine balloon tamponade or packing [ 18 ]. Additionally, the current indication for UAE is typically reserved for patients who are hemodynamically stable, appear to have persistent slow bleeding, and have failed less invasive therapy (uterotonic agents, uterine massage, uterine compression, and manual removal of any clots) [ 18 ]. The limited integration of IR into the standard PPH management pathways may be due to several factors, including variability in clinical decision-making, limited availability, and access to IR resources in certain regions, or insufficient awareness among providers regarding the potential benefits of UAE. To better improve response time and survival outcomes, some solutions to propose changes to the current management guidelines would include earlier integration of IR teams based on a more in-depth and refined risk factor stratification, better provider education, and expanding IR resources to improve accessibility, ultimately reducing maternal and neonatal morbidity and mortality. This study poses several limitations that should be considered. For instance, the reliance on data from TriNetX, which is sourced from different electronic medical records (EMR), may introduce potential biases, including variability in documentation and coding accuracy. Institutional differences in UAE indications, protocols, and resource availability further limit the generalizability of these findings. Future directions for research should include age-stratified analyses to better understand the risks and benefits of UAE across different populations, particularly considering the fertility implications for younger patients. Lastly, long-term outcomes studies focusing on reproductive health, maternal well-being, and neonatal outcomes can provide crucial information for comprehensive understanding of UAE’s role in PPH management. Conclusion This study identified key risk factors, including maternal, pregnancy, and peripartum factors that are linked to the need for uterine artery embolization in postpartum hemorrhage. Recognizing these risk factors can allow clinicians to identify patients at increased risk early, involve interventional radiology sooner, and coordinate care more effectively. 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Minim Invasive Therapy Allied Technol 31(2):276–283. 10.1080/13645706.2020.1789662 Matsuzaki S, Lee M, Nagase Y et al (2021) A systematic review and meta-analysis of obstetric and maternal outcomes after prior uterine artery embolization. Sci Rep 11(1):16914. 10.1038/s41598-021-96273-z Committee on Practice Bulletins-Obstetrics (2017) Practice Bulletin 183: Postpartum Hemorrhage. Obstet Gynecol 130(4):e168–e186. 10.1097/AOG.0000000000002351 Additional Declarations The authors declare no competing interests. Supplementary Files Supplementarytable1.docx ICD-10 Procedure Codes Supplementarytable2.docx ICD-10 Diagnosis and CPT codes Cite Share Download PDF Status: Posted Version 1 posted 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-7411786","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":502770059,"identity":"9a4cbb9d-89f8-4b9c-9216-27b892137dff","order_by":0,"name":"Devin Reddy","email":"","orcid":"","institution":"Beth Israel Deaconess Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Devin","middleName":"","lastName":"Reddy","suffix":""},{"id":502770060,"identity":"14546a19-1bdc-4cd7-9976-e68cf5825f12","order_by":1,"name":"Bunnarin Theng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuElEQVRIiWNgGAWjYBACAwYGNhAtxwBhMBOjhRmsxRiogUQtiQ1EazGXyD/24OOO2vQN97vTHjBUWCc2ENJiOSOZ3XDmmeO5G47xbjdgOJNOWIvBjWQ2ad62YyAt2yQY2w4TqeVv27F0A7CWf8RqYWyrSYBoaSBCi2XPYzPJ3rYDhjOP5W43SDiWbkxQizl74jOJn2118nyHz2578KHGWpagFig4DKESiFQOAnUkqB0Fo2AUjIIRBwCxPz+NsX8PjAAAAABJRU5ErkJggg==","orcid":"","institution":"University of Texas Medical Branch at Galveston","correspondingAuthor":true,"prefix":"","firstName":"Bunnarin","middleName":"","lastName":"Theng","suffix":""},{"id":502770061,"identity":"9b179b7d-ca8b-471e-8630-12332c53e26c","order_by":2,"name":"Aparna Medarametla","email":"","orcid":"","institution":"University of Texas Medical Branch at Galveston","correspondingAuthor":false,"prefix":"","firstName":"Aparna","middleName":"","lastName":"Medarametla","suffix":""},{"id":502770062,"identity":"57db6139-4ec9-43d6-9bf7-bcaefd07d8dc","order_by":3,"name":"Haroon Dossani","email":"","orcid":"","institution":"University of Texas Medical Branch at Galveston","correspondingAuthor":false,"prefix":"","firstName":"Haroon","middleName":"","lastName":"Dossani","suffix":""},{"id":502770063,"identity":"18338535-b715-4d54-850f-031f6d5010bb","order_by":4,"name":"Gautam Edhayan","email":"","orcid":"","institution":"University of Texas Medical Branch at Galveston","correspondingAuthor":false,"prefix":"","firstName":"Gautam","middleName":"","lastName":"Edhayan","suffix":""},{"id":502770064,"identity":"78bdcb85-5f3c-4238-b6a3-386b156cb0b6","order_by":5,"name":"Arsalan Saleem","email":"","orcid":"","institution":"University of Texas Medical Branch at Galveston","correspondingAuthor":false,"prefix":"","firstName":"Arsalan","middleName":"","lastName":"Saleem","suffix":""}],"badges":[],"createdAt":"2025-08-19 21:36:02","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-7411786/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7411786/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":89994387,"identity":"c629d4ea-3a0b-42de-9a30-3b13ca2aea20","added_by":"auto","created_at":"2025-08-27 07:51:00","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":60688,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 1. \u003c/strong\u003ePPH Treatment Protocol. Adapted from [4,5].\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7411786/v1/034c19a7a4d5033421ef934e.png"},{"id":89994394,"identity":"7c782ea0-6a86-4a5a-b295-7929bac06296","added_by":"auto","created_at":"2025-08-27 07:51:00","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":34170,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFigure 1a.\u003c/strong\u003e RR with 95% confidence intervals (CI) for maternal history risk factors in patients undergoing UAE for PPH.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 1b.\u003c/strong\u003e RR with 95% CI for pregnancy characteristics risk factors for PPH treated with UAE.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 1c.\u003c/strong\u003e RR with 95% CI of peripartum events risk factors for PPH treated with UAE.\u003c/p\u003e","description":"","filename":"1abc.png","url":"https://assets-eu.researchsquare.com/files/rs-7411786/v1/ea3d4fca9749618832d285c1.png"},{"id":89995729,"identity":"ddf2c0a1-e28c-46c4-877e-dc37f2841e66","added_by":"auto","created_at":"2025-08-27 07:59:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":663974,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7411786/v1/43f5a3b2-dd8c-4303-bc43-6922c2ad37f7.pdf"},{"id":89994388,"identity":"f7493d20-447c-478c-bdbb-8ff66cedd367","added_by":"auto","created_at":"2025-08-27 07:51:00","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":13117,"visible":true,"origin":"","legend":"\u003cp\u003eICD-10 Procedure Codes\u003c/p\u003e","description":"","filename":"Supplementarytable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7411786/v1/eb56f7669174ecb7973d0426.docx"},{"id":89994393,"identity":"91c921fd-d0e6-4d9b-bc46-34f6bf532874","added_by":"auto","created_at":"2025-08-27 07:51:00","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":9810,"visible":true,"origin":"","legend":"\u003cp\u003eICD-10 Diagnosis and CPT codes\u003c/p\u003e","description":"","filename":"Supplementarytable2.docx","url":"https://assets-eu.researchsquare.com/files/rs-7411786/v1/ff1ef00f8ef1f91ee865ce1e.docx"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eRisk Factors Preceding Uterine Artery Embolization in the Setting of Postpartum Hemorrhage\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePostpartum hemorrhage (PPH) is a severe obstetric complication seen in nearly 10% of deliveries and is responsible for over one quarter of maternal deaths worldwide [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The American College of Obstetricians and Gynecologists (ACOG) define PPH as the cumulative loss of at least 1,000 mL of blood, or blood loss presenting with symptomatic hypovolemia within 24 hours of delivery [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. PPH is most commonly attributed to uterine atony, or inadequate uterine contraction after birth resulting in insufficient placental vessel compression [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eRisk factors for uterine atony include multiple gestation pregnancy, polyhydramnios, and fetal macrosomia, all of which cause uterine enlargement; pathology that alters the structure of the uterus such as uterine fibroids; and prolonged exposure to medications or infection during the peripartum period such as general anesthesia, oxytocin, or chorioamnionitis. Rarer obstetric complications that increase the risk of PPH include retained products of conception, abnormal placental structure or attachment (e.g., placenta accreta spectrum), trauma to the uterus and birth canal, and coagulopathies that may be inherent or acquired (abruptio placentae, gestational hypertension, amniotic fluid embolism, or anticoagulant use). Antepartum risk factors for developing PPH must also be considered: advanced maternal age, preeclampsia, use of in vitro fertilization or intracytoplasmic sperm injections, and increased body mass index [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePPH has both acute and chronic effects on maternal morbidity and mortality, including but not limited to anemia requiring transfusion, acute respiratory distress syndrome, hypovolemic shock, disseminated intravascular coagulation, acute renal failure, Sheehan syndrome, loss of fertility, and death [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Due to the severity of these complications, it is imperative that patients at risk for PPH are identified as early as possible and several treatment options exist to mitigate or circumvent the effects of this condition (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThough a hysterectomy can be a life-saving procedure in the setting of refractory PPH, this definitive intervention is also associated with substantial morbidity for young mothers. Tsolakidis et al. have previously described the significantly elevated risk of complications in pregnancy-related hysterectomies as compared to non-obstetric hysterectomies [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. These complications most commonly include bladder and/or ureteral injury, wound dehiscence, and venous thrombosis. Damage to the pelvic floor muscles may result in incontinence and recurrent urinary tract infections, which can be severely debilitating for young mothers and patients in general.\u003c/p\u003e\u003cp\u003eOne method of conservative management of PPH that may be considered prior to hysterectomy is uterine artery embolization (UAE). UAE is a minimally invasive procedure conducted by an interventional radiologist (IR) that has the added benefit of preserving the patient\u0026rsquo;s fertility and decreasing their hospital stay [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In a national inpatient sample study by Webster et al., PPH patients managed with UAE were 0.38 times less likely to have a prolonged hospital stay compared to patients who received a hysterectomy [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In a systematic review by Sathe et al., 89% of UAE procedures were successful in treating PPH [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Though more commonly used in the treatment of refractory or painful leiomyomas (uterine fibroids), UAE has become an increasingly utilized method of reducing PPH.\u003c/p\u003e\u003cp\u003eThe techniques for UAE have previously extensively been described in literature by Brown et al. and Ruiz Labarta et al. and will not be explored in this paper. Potential for rebleeding is the most common complication of UAE (albeit low). Other rare complications of UAE include uterine infarction, ovarian insufficiency, endometritis, and abscess formation. Few contraindications exist to UAE, namely hemodynamic instability and uncontrolled coagulopathy. Risk factors for a failed UAE procedure include narrow uterine arteries, disseminated intravascular coagulation (due to decreased clotting power secondary to consumption of clotting factors), cesarean delivery and receiving large volumes of blood transfusion [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDespite numerous studies providing evidence in favor of employing UAE as a conservative treatment option before considering total hysterectomy, IR continues to be an underutilized service in obstetrics and maternal-fetal medicine and often becomes involved much later in the management of PPH patients, as detailed in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e1\u003c/span\u003e [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In fact, the International Federation of Gynecology and Obstetrics (FIGO) identifies skilled human resources as a limitation for the implementation of this life-saving technique [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Current guidelines call for more evidence regarding the clinical benefits of IR, safety of ionizing radiation exposure, and real-time implementation of UAE procedures in hospitals and by clinicians, which at present appears to be more subjective based on access to IR facilities and physician comfort.\u003c/p\u003e\u003cp\u003eThe purpose of this study, therefore, is two-fold: to analyze the risk factors for mothers who developed PPH and were treated with UAE, and to stratify these risk factors and identify patients at high risk for PPH who would benefit from an IR consult and subsequent UAE treatment.\u003c/p\u003e"},{"header":"Materials \u0026 Methods","content":"\u003cp\u003eThe data for this case-control study was sourced from the TriNetX platform and was deemed IRB-exempt via the University of Texas Medical Branch institutional IRB. TriNetX (Cambridge, MA) is a database of anonymized patient CPT and ICD-10 codes from healthcare organizations across the globe. A list of the CPT and ICD-10 codes used in this study can be found in the Supplementary Materials.\u003c/p\u003e\u003cp\u003eWithin TriNetX, patients who had received the ICD-10 code for PPH (O72) between April 2014 and April 2024 were anonymously identified from 78 healthcare organizations in the United States. Our study population was then divided into two groups, those who underwent UAE within one month of the first instance of PPH (the \u0026lsquo;cases\u0026rsquo;), and those who did not (the \u0026lsquo;controls\u0026rsquo;; Supplementary Table\u0026nbsp;1). Next, the groups were compared on historical factors present in the patient\u0026rsquo;s chart up to one year before the first instance of the PPH ICD-10 code (Supplementary Table\u0026nbsp;2).\u003c/p\u003e\u003cp\u003eStatistical analysis was performed in the TriNetX database and with Microsoft Excel. The null hypothesis for the analyzed historical factors was no difference between the two groups. For each historical factor, the incidence, risk ratio, and attributable risk percent for each historical variable was calculated. Categorical data (presented as incidence) was analyzed with chi-square tests with an alpha level of 0.05. Risk ratios were reported in this study instead of odds ratios because the incidence for each historical factor was rare (\u0026lt;\u0026thinsp;10%) in both groups.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e158,741 patients with PPH were identified during the study period. Of these, 796 patients underwent UAE, while 157,945 did not. The mean age of patients who underwent UAE was 32.1\u0026thinsp;\u0026plusmn;\u0026thinsp;6.4 years, compared to 29.7\u0026thinsp;\u0026plusmn;\u0026thinsp;6.6 years for those who did not. Among these patients, many risk factors were identified and grouped into three categories: maternal history, pregnancy characteristics, and peripartum events.\u003c/p\u003e\n\u003ch3\u003eMaternal History\u003c/h3\u003e\n\u003cp\u003ePatients with history of uterine fibroids demonstrated the highest increased risk for PPH requiring UAE, with a risk ratio (RR) of 2.37 and attributable risk (AR) of 57.86% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Comparatively, patients with a history of uterine scars from previous surgery (RR 2.34, AR 57.20%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) and endometriosis (RR 1.84, AR 45.79%, p\u0026thinsp;=\u0026thinsp;0.011) were also associated with a significantly increased risk for PPH requiring UAE. The remainder of maternal history, including preterm labor, previous pregnancy complications, chronic or gestational anemia, diabetes mellitus in pregnancy, and obesity did not show any statistically significant associations (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSummary of Risk Factors for UAE Utilization in PPH\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCategories\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eRisk Factors\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eIncidence in UAE (+) (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eIncidence in UAE (-) (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRR\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eAR (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eMaternal History\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUterine Fibroids\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e57.86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUterine Scar from Previous Surgery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e57.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eEndometriosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e45.79\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.011*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDiabetes Mellitus in Pregnancy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e14.72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.102\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePrevious Pregnancy Complications\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e12.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.1179\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChronic/Gestational Anemia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.7468\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePreterm Labor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.8786\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eObesity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.3004\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePregnancy Characteristics\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePlacental Abnormalities\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e59.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eConception via ART\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e59.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAdvanced Maternal Age\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.78\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.78\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e43.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre-Eclampsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e37.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUterine Overdistension\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.41\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e29.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHigh-Risk Pregnancy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e12.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.0553\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePeripartum Events\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eShock\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e7.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e18.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e94.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDIC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6.77\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e14.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e93.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAcute Anemia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e4.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e76.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eThrombocytopenia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e57.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCesarean Delivery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e55.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChorioamnionitis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e13.07\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.244\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLong labor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.8665\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePreterm Labor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.0142*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost-Term Pregnancy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.0021*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eObstetric Trauma or Laceration\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eVaginal Delivery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003e* Indicates statistically significant association\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003ePregnancy Characteristics\u003c/h3\u003e\n\u003cp\u003ePlacental abnormalities and conception by assisted reproduction technology (ART) were associated with significant risk factors for PPH, with RR of 2.48 and 2.47, AR of 59.66% and 59.52% respectively (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Advanced maternal age (\u0026ge;\u0026thinsp;35 years) and pre-eclampsia also contributed significantly (RR 1.78 and 1.60 and AR 43.74% and 37.56% respectively) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Lastly, uterine overdistension, whether due to multiple gestations or macrosomia, demonstrated a significant association (RR 1.41, AR 29.17%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) while high-risk pregnancies approached significance but did not meet the threshold (RR 1.15, AR 12.85%, p\u0026thinsp;=\u0026thinsp;0.0553).\u003c/p\u003e\n\u003ch3\u003ePeripartum Events\u003c/h3\u003e\n\u003cp\u003eShock was the most significant peripartum risk factor, with an RR of 18.04 and AR of 94.46% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), followed by disseminated intravascular coagulation (DIC) with RR 14.74, AR 93.21%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001. Another coagulopathy, thrombocytopenia, is also associated with increased risk (RR 2.35, AR 57.39, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). On the other hand, cesarean delivery was a major peripartum risk factor, with an RR of 2.26 and an AR of 55.81% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) while vaginal delivery (VD) was associated with relatively decreased risk (RR 0.5, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Other risk factors, such as preterm labor (RR 0.75, p\u0026thinsp;=\u0026thinsp;0.0142), post-term labor (RR 0.71, p\u0026thinsp;=\u0026thinsp;0.0021), and obstetric trauma or laceration (RR 0.59, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) were all significantly associated with decreased risk of UAE utilization. However, chorioamnionitis (RR 1.15, p\u0026thinsp;=\u0026thinsp;0.244) and long labor (RR 1.04, p\u0026thinsp;=\u0026thinsp;0.8665) showed limited significant associations.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWhile the risk factors for postpartum hemorrhage (PPH) have been previously well-established, this study further explores the PPH patients that undergo uterine artery embolization (UAE). Our findings indicate that obesity and preterm labor are associated with minimal reduced risk, while factors such as post-term pregnancy, obstetric trauma or lacerations, and vaginal delivery are significantly linked to a lower risk of PPH. This study also examined additional risk factors such as coagulopathies (shock, DIC, acute anemia, thrombocytopenia), endometriosis, advanced maternal age, which are all associated with significantly increased risk for PPH requiring UAE. This approach highlights the importance of considering less traditionally recognized contributors to hemorrhage. Additionally, understanding these risk factors allows for early identification of patients at higher risk of requiring UAE, guiding earlier intervention strategies. This includes implementing systemic models to enhance monitoring during delivery and establishing protocols that integrate IR teams, either through pre-procedure consultation or standby readiness. Such targeted approaches have been shown to significantly improve outcomes by reducing the likelihood of hysterectomy and minimizing complications [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eUAE is increasingly recognized as an effective intervention for refractory PPH. A retrospective study by Akoi et al. found that UAE had a 85% clinical success rate in achieving adequate hemostasis in patients with refractory PPH, offering life-saving outcomes, particularly in cases where surgical interventions may be delayed or contraindicated [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Further benefits of UAE include fertility preservation, shorter hospital stays, and a lower risk profile compared to cesarean hysterectomy. For instance, in a large multicenter study, UAE was associated with a median maternal length of hospital stay of 5 days, a mean intraoperative transfusion of 3.7 units of packed red blood cells (pRBCs), and the morbidity and mortality rates of 1.6% compared to 22 days in the hospital, 4.6 units of pRBCs, and 34.9% mortality rate [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Additionally, cesarean hysterectomy has been shown to pose significant surgical risks. A cross-institutional observational study by Shellhaas et al showed that major maternal complications of cesarean hysterectomy include transfusion of red blood cells (84%) and other blood products (34%), fever (11%), subsequent laparotomy (4%), ureteral injury (3%), and death (1.6%) [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eWhile UAE has been shown to be a safer procedure for controlling hemorrhage with more favorable safety profile compared to surgical alternatives, there are also concerns regarding its potential impact on future fertility, particularly among younger patients who may desire future pregnancies. To this day, the effects of UAE on menstruation and fertility have not been sufficiently addressed and the relationship between the amount of bleeding and the time to embolization and the success of UAE, including fertility and the return of menstruation, are still not well understood [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In addition, studies have shown that prior UAE is a significant risk factor for placenta accreta spectrum and increases the risk of PPH in subsequent pregnancies, requiring close monitoring for potential complications [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eMoreover, it was noted that the majority of patients with PPH in this study did not undergo UAE, with only 0.5% did. According to ACOG guidelines, the current PPH management include manual uterine massage and medical interventions with uterotonic agents (eg, oxytocin, methylergonovine, and misoprostol) as the first-line treatment, followed by intrauterine balloon tamponade or packing [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Additionally, the current indication for UAE is typically reserved for patients who are hemodynamically stable, appear to have persistent slow bleeding, and have failed less invasive therapy (uterotonic agents, uterine massage, uterine compression, and manual removal of any clots) [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The limited integration of IR into the standard PPH management pathways may be due to several factors, including variability in clinical decision-making, limited availability, and access to IR resources in certain regions, or insufficient awareness among providers regarding the potential benefits of UAE. To better improve response time and survival outcomes, some solutions to propose changes to the current management guidelines would include earlier integration of IR teams based on a more in-depth and refined risk factor stratification, better provider education, and expanding IR resources to improve accessibility, ultimately reducing maternal and neonatal morbidity and mortality.\u003c/p\u003e\u003cp\u003eThis study poses several limitations that should be considered. For instance, the reliance on data from TriNetX, which is sourced from different electronic medical records (EMR), may introduce potential biases, including variability in documentation and coding accuracy. Institutional differences in UAE indications, protocols, and resource availability further limit the generalizability of these findings. Future directions for research should include age-stratified analyses to better understand the risks and benefits of UAE across different populations, particularly considering the fertility implications for younger patients. Lastly, long-term outcomes studies focusing on reproductive health, maternal well-being, and neonatal outcomes can provide crucial information for comprehensive understanding of UAE\u0026rsquo;s role in PPH management.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study identified key risk factors, including maternal, pregnancy, and peripartum factors that are linked to the need for uterine artery embolization in postpartum hemorrhage. Recognizing these risk factors can allow clinicians to identify patients at increased risk early, involve interventional radiology sooner, and coordinate care more effectively. By using risk-based protocols, response times can be improved, complications reduced, and maternal and neonatal outcomes optimized.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHersh AR, Carroli G, Hofmeyr GJ et al (2024) Third stage of labor: evidence-based practice for prevention of adverse maternal and neonatal outcomes. Am J Obstet Gynecol 230(3):S1046\u0026ndash;S. 1060.e1\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAmerican College of Obstetricians and Gynecologists (2017) Postpartum hemorrhage. Practice Bulletin 183. 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Obstet Gynecol 114(2 Pt 1):224\u0026ndash;229. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/AOG.0b013e3181ad9442\u003c/span\u003e\u003cspan address=\"10.1097/AOG.0b013e3181ad9442\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKim MJ, Kim IJ, Kim S, Park IY (2022) Postpartum hemorrhage with uterine artery embolization: the risk of complications of uterine artery embolization. Minim Invasive Therapy Allied Technol 31(2):276\u0026ndash;283. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1080/13645706.2020.1789662\u003c/span\u003e\u003cspan address=\"10.1080/13645706.2020.1789662\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMatsuzaki S, Lee M, Nagase Y et al (2021) A systematic review and meta-analysis of obstetric and maternal outcomes after prior uterine artery embolization. Sci Rep 11(1):16914. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41598-021-96273-z\u003c/span\u003e\u003cspan address=\"10.1038/s41598-021-96273-z\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCommittee on Practice Bulletins-Obstetrics (2017) Practice Bulletin 183: Postpartum Hemorrhage. Obstet Gynecol 130(4):e168\u0026ndash;e186. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/AOG.0000000000002351\u003c/span\u003e\u003cspan address=\"10.1097/AOG.0000000000002351\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"The University of Texas Medical Branch at Galveston","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Uterine artery embolization, Postpartum hemorrhage, Risk factors, Case control study, Interventional radiology","lastPublishedDoi":"10.21203/rs.3.rs-7411786/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7411786/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eUterine artery embolization (UAE) is a minimally invasive, uterine-sparing intervention that can help control postpartum hemorrhage (PPH) when more conservative management has failed. While risk factors for PPH are well established, those leading to the use of embolization remain unclear. This study aimed to determine how maternal history, pregnancy characteristics, and peripartum events impact the utilization of UAE for PPH in the peripartum period.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e\u003cp\u003eThis case-control study queried electronic health records from 78 healthcare organizations in the United States for patients with PPH from April 2014 to April 2024. Patients who did and did not undergo UAE were then analyzed for risk factors in the preceding year from their initial event.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eAmong 158,741 patients with PPH, 796 underwent UAE (mean age 32.1\u0026thinsp;\u0026plusmn;\u0026thinsp;6.4 years). Significant risk factors included uterine scar (AR 57.20%), fibroids (AR 57.86%), endometriosis (AR 45.79%), advanced maternal age (AR 43.74%), assisted reproductive technology (AR 59.52%), uterine overdistension (AR 29.17%), placental abnormalities (AR 59.66%), pre-eclampsia (AR 37.56%), cesarean delivery (AR 55.81%), anemia (AR 76.62%), disseminated intravascular coagulation (AR 93.21%), thrombocytopenia (AR 57.39%), and shock (AR 94.46%) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Other identified factors did not significantly impact UAE use.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eIdentifying these critical risk factors can help preemptively identify patients at higher risk of needing UAE and can be used to improve multidisciplinary coordination of care and response times, potentially reducing maternal and neonatal morbidity and mortality.\u003c/p\u003e","manuscriptTitle":"Risk Factors Preceding Uterine Artery Embolization in the Setting of Postpartum Hemorrhage","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-27 07:50:55","doi":"10.21203/rs.3.rs-7411786/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"661ea662-ed31-4160-a7e6-c9abd76f343b","owner":[],"postedDate":"August 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":53636415,"name":"Vascular Medicine"},{"id":53636416,"name":"Nuclear Medicine \u0026 Medical Imaging"}],"tags":[],"updatedAt":"2025-08-27T07:50:55+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-27 07:50:55","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7411786","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7411786","identity":"rs-7411786","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}