Myometrial Defect Research Articles

Reevaluating the variation of cesarean scar defect.

The increasing incidence of cesarean sections has led to a higher prevalence of cesarean scar defects (CSDs), predominantly characterized by postmenstrual bleeding in affected women. CSD manifests in various forms, including isolated myometrial defects, intrauterine cystic protrusions, and extrauterine cystic extensions. The pathophysiological mechanisms underpinning CSD and its associated symptoms remain insufficiently understood. This review explores the pathogenesis of CSD, highlights its morphological characteristics with an emphasis on variable clinical diversity, and addresses the challenges for future research. A comprehensive narrative review was conducted using electronic databases, including PubMed and Google Scholar, to identify 41 relevant literatures published up to December 31, 2023. The myometrium comprises two distinct layers-the inner and outer myometrium-with differences in their origin, structure, and function. Disruptions within these layers contribute to CSD development. Histopathologically, symptomatic CSD may be linked to uterine scar endometriosis, cystic adenomyosis, or endometrial cysts, suggesting that CSD, particularly those necessitating surgical intervention, are not limited to myometrial defects but may also involve iatrogenic endometriosis or adenomyosis, thereby exacerbating clinical symptoms. This review provides an updated understanding of the histopathological features and classification of CSD, with an emphasis on elucidating its underlying pathogenesis.

A Case Report of Uterine Myometrial Defect Following Hayman and Square Sutures for Postpartum Hemorrhage

A Case Report of Uterine Myometrial Defect Following Hayman and Square Sutures for Postpartum Hemorrhage

Isthmocele‑an iatrogenic pathology: A prospective study in a tertiary unit.

Isthmocele, also known as uterine niche, refers to a myometrial defect of the anterior wall of the uterine isthmus, specifically at the site of the previous C-section scar. The prevalence of isthmocele has increased in tandem with the rise in deliveries by caesarean section. Risk factors include aspects related to the surgical procedure. The present study aimed to assess the relationship between various suture types and the development of a niche. The analysis of the present study is based on data collected from the evaluation of 52 patients, 6 weeks post C-section performed in 'Saint Pantelimon' Hospital in Bucharest, Romania. The parameters examined included patient age, the number of previous births by C-section, the type of suture used and uterine anatomy. Out of all the 52 patients, 42.3% developed an isthmocele. The results confirm a significant association between the presence of the niche and the type of suture of the first layer, proving that when non-locking continuous suture was used, the absence of niche was observed in most cases, while using the locking continuous suture was associated with more niches. Using the continuous locking suture for the first layer was associated with severe niches, while no severe niches were observed in patients with the other two types of sutures. There is a statistically significant association between the use of continuous locking sutures for uterine closure in the first layer and the development of a uterine niche. Furthermore, all instances of severe niches were linked to this type of suture, compared with continuous non-locking suture or interrupted suture. Given the escalating rate of C-sections, further research is crucial to identify the suture type that minimizes the risk of isthmocele formation. The present study's limitations revolve around its exclusive focus on a single institution and the relatively small sample size.

Barbed vs conventional sutures for cesarean uterine scar defects: a randomized clinical trial

BackgroundThe role of barbed sutures in preventing myometrial defects and enhancing postpartum outcomes after cesarean section (C-section) is uncertain. ObjectiveThis study compared clinical and ultrasonographic outcomes of uterine scar defects after C-section with barbed and conventional smooth thread sutures. Study DesignThis was a multicenter, parallel-group, randomized, controlled clinical trial. Four obstetrics and gynecology departments across three Japanese healthcare regions were included. The participants were women requiring their first cesarean delivery between May 2020 and March 2023. Of the 1211 participants enrolled, 298 underwent C-section and 253 were followed up until July 2023. Participants with singleton pregnancies were randomly assigned (1:1 ratio) to receive either conventional or spiral thread sutures with a double-layer continuous suture. The study period comprised the time of consent to the 6- to 7-month examination. The primary endpoint was the rate of scar niches >2 mm evaluated using transvaginal ultrasonography at 6 to 7 months after surgery. Additional metrics included the total operative time, suture application time, operative blood loss, number of additional sutures required for hemostasis, maternal surgical complications, postoperative infections, surgeon's years of experience, and individual subscale scores. ResultsAll data of the 220 participants (barbed suture group: 110; conventional suture group: 110) were available, thus enabling a full analysis set. A comparison of the barbed and conventional suture groups, respectively, revealed the following: niche length, 2.45±1.65 mm (range: 1.0–6.7) vs 3.79±1.84 mm (range: 1.0–11.0) (P<.001); niche depth, 1.78±1.07 mm (range: 1.0–5.7) vs 2.70±1.34 mm (range: 1.0–7.3) (P<.001); residual myometrial thickness (RMT), 8.46±1.74 mm (range: 4.8–13.0) vs 7.07±2.186 mm (range: 2.2–16.2) (P<.001); and niche width, 1.58±2.73 mm (range: 0.0–14.0) vs 2.88±2.36 mm (range: 0.0–11.0) (P<.001), respectively. The barbed suture group exhibited no defects and an RMT <3 mm. Furthermore, the barbed suture group had a lower rate of uterine niches (29.1%; n=32/110) than the conventional suture group (68.2%; n=75/110). Secondary outcomes showed no significant differences in operative times, maternal surgical complications, or postoperative complications. ConclusionDouble-layer barbed sutures during cesarean delivery may prevent C-section scar defects and postoperative complications.El resumen está disponible en Español al final del artículo.

An unusual case of Uterine window revealing the placenta: A Diagnostic dilemma between Scar dehiscence and the Placenta Accreta Spectrum.

Uterine scar dehiscence, or the "uterine window," is a complication of a repeat cesarean section. Preterm delivery, caesarean sections performed more than twice in the past, or less than a 24-month interval between deliveries are all connected with an increased risk. The terms Placenta Accreta Spectrum (PAS) and uterine scar dehiscence are frequently used interchangeably. A 25-year-old unbooked pregnant woman, gravida 3 para 2 live 1, presented to OPD at 37 weeks gestation. During the intraoperative phase, we discovered a silent scar dehiscence with partially visible placental lobes under the intact serosa mimicking the Placenta Accreta Spectrum. A lower-segment caesarean section was performed, and the placenta was totally separated. After the cesarean incision was closed, the myometrial defect was corrected. It is crucial to distinguish it from disorders in the Placenta Accreta Spectrum, as prenatal imaging can be deceptive if not performed with the requisite expertise to distinguish between the two conditions. This distinction will inform the treatment strategies for uterine dehiscence and PAS disorders, which are distinct.

Laparoscopic removal of heterotopic cesarean scar pregnancy

ObjectiveTo present the laparoscopic management of heterotopic cesarean scar pregnancy and discuss other treatment options. DesignSurgical video article. The Institutional Ethics Committee approved the video reproduction. SettingTertiary referral university hospital PatientA 29-year-old woman with spontaneous heterotopic cesarean scar pregnancy presented for vaginal spotting. Ultrasound revealed two gestational sacs at 7 weeks and 6 days of gestation with fetal cardiac activity. One sac was in a normal intrauterine location and the other in a previous cesarean section scar. InterventionsScar pregnancy was excised laparoscopically while preserving intrauterine pregnancy. No additional measures were taken to reduce bleeding. The bladder was filled with 150 cc isotonic to determine its boundaries. The peritoneum was dissected away from the cervix. After removing the ectopic pregnancy material, the myometrial defect was excised. The uterine wall was closed in three layers using 2-0 V-LocTM sutures. Main outcome measuresOngoing intrauterine pregnancy after laparoscopic removal of cesarean scar pregnancy and term delivery. ResultsThe procedure was completed in 67 min. Total blood loss was <100 cc. Ongoing pregnancy follow-up was uneventful. Delivery was planned for the 37th-38th weeks. Although instructed to visit immediately after experiencing pain, the patient arrived after the 38th week and reported having pain for 2 days. During cesarean section, a rupture was observed at the previous incision site, which was fortunately incomplete. A healthy male baby (weight, 3210 g; Apgar score, 9/10) was delivered. ConclusionsThe most common approach for heterotopic scar pregnancy is embryo reduction with potassium chloride injection. However, the mass persists in the scar area, resulting in complications associated with excessive bleeding during cesarean section in approximately half cases. Moreover, almost all published cases of embryo reduction resulted in premature births before week 36. Considering the present case, laparoscopic surgery may be appropriate for managing heterotopic cesarean scar pregnancy by preserving intrauterine pregnancy.

Repair of a chronic myometrial defect with successful pregnancy outcome

To surgically demonstrate preconceptional laparoscopic repair of a chronic myometrial defect with mesh reinforcement, resulting in a successful pregnancy outcome. Video case report. The Institutional Ethical Committee was consulted, and the requirement for approval was waived because the video describes a modified surgical technique. The patient included in this video gave consent for publication of the video and posting of the video online, including on social media, the journal website, scientific literature websites (such as PubMed, ScienceDirect, Scopus, and others), and other applicable sites. A referral advanced gynecological endoscopy center. A 27-year-old woman (P0A1) was diagnosed with myomas during pregnancy, resulting in miscarriage at 22 weeks. Laparotomy and myomectomy were performed 2 months later, and three 8-cm myomas were removed. The endometrial cavity opened posteriorly during surgery, and retained products of conceptions were removed. Periconceptional imaging done after two years showed few intramural myomas and a deficient myometrium in the posterior fundal region. Laparoscopy revealed a defect in the posterior fundal aspect of the uterus with leakage of dye, which was converted to laparotomy and myomectomy with the repair of the myometrial defect. After 1 year, follow-up magnetic resonance imaging showed thinned-out posterior myometrium with a focal area of absent myometrium in the midline and endometrial prolapse. The patient was advised on surrogacy, but she wanted to repair the defect again and try for pregnancy, so she was referred to our center. With the background of a few case reports using mesh to reinforce myometrial repair (1, 2), we counseled the patient about the myometrial repair with the additional use of mesh as an off-label use. The risk of uterine rupture after myomectomy is rare (<1%) (3), but it is a severe complication. High-risk cases, like significant myometrial defects or previous ruptures, may require surgical correction. Native repair may not achieve optimal results in all cases. Alternative approaches, like the additional use of mesh or biological materials, have been reported (4). In this case, we demonstrate the use of dual mesh for scar repair. Synthetic mesh over the uterus is used in laparoscopic procedures like sacrohysteropexy and cerclage. We used Parietex (Covidien, New Haven, CT, USA) mesh, a composite macroporous polyester mesh usually used for ventral hernia repair. It has an outer hydrophilic, absorbable collagen barrier that reduces adhesion formation. Laparoscopically, after adhesiolysis, a significant defect was demonstrated on the posterior wall of the uterus (Fig.1). A complete resection of the fibrotic tissue along the edges of the scar defect was done to expose healthy myometrium. Myometrium was repaired in two layers, excluding the endometrium, with a V-Loc (Covidien, Dublin, Ireland) No. 1-0 suture. Parietex mesh was sutured over the repaired posterior myometrium to reinforce it (Fig.2). The postoperative myometrial thickness on imaging and pregnancy outcome. Postoperative ultrasound scan after 6 weeks demonstrated restoration of posterior wall myometrial thickness of 14 mm. The patient was conceived through invitro fertilization techniques 4 months after surgery. Antenatal follow-up was uneventful except for suspicion of posterior placenta accreta. She underwent an elective cesarean section with uterine artery embolization at 34 weeks and delivered a healthy infant weighing 1,950 g. Placental removal was uneventful. On inspection, the posterior surface of the uterus was intact without dehiscence, meshing in situ with minimal adhesions (Fig.3). Myometrial scar defects can cause potential obstetric complications. Native repair of scar defects may not achieve optimal results, as in our case. Mesh repair of myomectomy scar defects can be used as an alternative approach, as exemplified in this case. However, further studies are required to establish the safety and efficacy of this approach.

Isthmocele correction: resectoscopic, laparoscopic or both?

An isthmocele is a myometrial defect in the site of the caesarean scar. In symptomatic women with abnormal uterine bleeding and secondary infertility, surgical correction can be considered. Most authors advocate that when there's a residual myometrium ≥ 3mm it can be corrected through resectoscopic approach and when < 3mm the treatment should be laparoscopic, eventually guided by diagnostic hysteroscopy. Both these techniques have important limitations; therefore, the authors propose combining both techniques, in the same procedure, in order to overcome them. To demonstrate the advantages of a surgical technique for correction of an isthmocele using both resectoscopic and laparoscopic resection. A stepwise demonstration of the technique with narrated video footage. Intraoperative data and outcomes in the patient's follow-up. One month after the surgery the patient was asymptomatic, reporting a resolution of the uterine abnormal bleeding, and the ultrasound showed a full correction of the isthmocele. A combination of resectoscopic and laparoscopic resection, in correcting bigger isthmoceles, is a good option to fully excise all the fibrotic tissue. This video aims to demonstrate the benefits of using a technique combining resectoscopic and laparoscopic resection for correcting larger isthmoceles.

Etiology behind canine uterine inertia: Role of uterine expression of MLCK4, MYH2, and PKC genes

Dystocia is an obstetrical emergency, and primary uterine inertia (PUI) is the major etiological reason among the more prevalent maternal causes in dogs. The present study involved the relative expression analysis of genes associated with myometrial contraction in medium-sized dog breeds with uterine inertia. Dogs without any progress in the parturition process even after four hours of the onset of labor and the absence of uterine contractions were considered to have complete primary uterine inertia (CPUI, n = 9). Dogs that had expelled at least one fetus and made no further progress in parturition in the absence of active uterine contraction were considered to be experiencing partial primary uterine inertia (PPUI, n = 6). Dogs with the fetal cause of dystocia (FCD), i.e., obstructive dystocia, were taken as the third (n = 7) group. Uterine tissue samples were collected during cesarean section in each group, RNA was isolated, and the relative expression of myometrial ACTA2, ACTG2, MLCK4, MYH2, and PKC genes was analyzed. The MLCK4 gene expression was downregulated in CPUI (P ≤ 0.05) and PPUI (P ≤ 0.01) when compared to FCD. The MYH2 gene expression was downregulated in PPUI in comparison to CPUI (P ≤ 0.01) and FCD (P ≤ 0.05). The PKC gene expression was upregulated in PPUI in comparison to FCD and CPUI (P ≤ 0.05). The downregulation of MLCK4 and MYH2 gene expressions recorded in PPUI indicated the possibility of myometrial defects. The possibility of myometrial defects was also observed in CPUI, but to a lesser degree, suggesting other etiologies.

Definition and diagnosis of cesarean scar ectopic pregnancies

Cesarean scar ectopic pregnancy is a rare type of ectopic pregnancy, where the pregnancy implants into a myometrial defect caused by a cesarean scar. Its incidence is predicted to increase given the global increase in cesarean deliveries. As most cesarean scar ectopic pregnancies present as failing pregnancies or patients chose termination of pregnancy, there is limited data on their natural history. However, early first trimester diagnosis is essential given the associated significant maternal morbidity. Transvaginal sonography is generally considered to be the optimal method for diagnosing cesarean scar ectopic pregnancy. There is no evidence that MRI adds to the diagnostic accuracy, and it is therefore not recommended for routine evaluation of cesarean scar ectopic pregnancy. There is no agreed reference standard for the diagnosis of cesarean scar ectopic pregnancy; therefore the validity of several proposed sonographic diagnostic criteria reported by different authors remains unknown. There are also various suggested classification systems for cesarean scar ectopic pregnancies, which divide them in differet types. However, the proposals are very heterogeneous and superiority of one classification system over another is yet to be established.

O-054 Live Births following Laparoscopic Caesarean Scar Niche Repair in patients with Secondary Infertility: A Self-Controlled Case Series and Literature Review.

Abstract Study question Does laparoscopic repair of caesarean scar niches as a treatment for secondary infertility improve live birth rates? Summary answer In our self-controlled case series, the laparoscopic repair of caesarean section niches in patients with secondary infertility has improved pregnancy and live birth rates. What is known already A niche is an iatrogenic myometrial defect due to abnormal tissue healing at a previous caesarean section scar site. Patients with a niche present with symptoms of vaginal discharge, abnormal uterine bleeding, chronic pelvic pain, dyspareunia and secondary infertility. As a niche is secondary to caesarean sections, rising caesarean section rates will lead to an increase in the rate of niche presentation and diagnosis. Study design, size, duration A retrospective review was performed of all women undergoing a hysteroscopy assisted laparoscopic niche repair between 2016 and 2023 at Guy’s and St Thomas’ Hospital in London. The primary outcome measure was live births. A literature review was performed to interrogate the currently available evidence on live birth rate following niche repair. Ultrasound images of the niche prior to and post repair, as well as intra-operative laparoscopic and hysteroscopic images and videos, are also presented. Participants/materials, setting, methods The cases were identified from the Assisted Conception Unit database. Only women who presented with secondary infertility with a diagnosis and repair of a niche were reported. Niche diagnosis was made in patients presenting with abnormal discharge, bleeding and fluid in the uterine cavity. Any incidental myometrial defect found on transvaginal ultrasound was also a diagnostic characteristic. Main results and the role of chance There are some reports in the literature on pregnancy outcome following niche repair. A scarcity of studies reporting specifically on live birth rates following repair, suggests this case series as unique. Eleven patients underwent caesarean section niche repair by two surgeons at our unit. The mean age at repair of the patients was 36. All patients had two or more years of subfertility on presentation, with a proportion having several failed in-vitro fertilisation (IVF) cycles prior to repair. The pregnancy rate, clinical pregnancy rate and live birth rate were 73% (8/11), 64% (7/11) and 45% (5/11) respectively. One patient had an early miscarriage at age 48 following repair and has not conceived again since. One patient underwent a second repair and is awaiting further investigations. Two patients have not yet conceived following repair, one of which had sickle cell disease, age factor and endometriosis. Our findings suggest a positive correlation between surgical repair of the niche and live births. However, this could be due to a strict selection criteria in a small sample size. In the two patients that did not have live births following repair, other factors of subfertility such as age, male factor and comorbidities could also play a role. Limitations, reasons for caution The small sample size can lead to selection bias and impairs the external validity of our findings. The likelihood of random error is high. Lack of a control group prevents any comparisons. Furthermore, all repairs were performed by the two surgeons which introduces operator bias. Outcome assessors were not blinded. Wider implications of the findings Subfertility secondary to niches is likely to be a growing challenge as caesarean section rates continue to increase. Our study suggests that surgical repair may improve live birth rates. We present our findings to augment the current international data on live birth rates following niche repair. Trial registration number not applicable

O-142 Surgical evacuation with adjuvant uterine artery embolization: a fertility preserving treatment for advanced live caesarean scar ectopic pregnancies

Abstract Study question Can advanced caesarean scar ectopic pregnancies be managed safely surgically whilst preserving future fertility? Summary answer With the available support of uterine artery embolization, suction and curettage can be an effective treatment for live advanced caesarean scar ectopic pregnancies, avoiding hysterectomy. What is known already Caesarean scar ectopic pregnancies (CSEPs) are associated with significant maternal morbidity and termination of pregnancy is often offered to patients to protect their health and fertility. Treatment of early first trimester CSEPs is usually effective and safe, but the management of more advanced cases is more challenging, and hysterectomy has been considered the treatment of choice for second trimester CSEPs. Study design, size, duration This was a retrospective cohort study in a tertiary referral centre between 2008-2023. Of 371 women diagnosed with CSEP, 22 (6%) had live advanced CSEPs. 17/22 (77%) patients opted for surgery, whilst the remaining five opted to continue with their pregnancies. CSEP was defined by implantation of the pregnancy into a myometrial defect caused by dehiscence of a lower uterine segment caesarean scar. Advanced CSEP was defined as crown rump length (CRL) of ≥ 40mm. Participants/materials, setting, methods A preoperative ultrasound was performed in each patient. All women underwent surgical evacuation under ultrasound guidance and insertion of modified Shirodkar cervical suture as a primary haemostatic measure. Additional haemostatic measures included uterine artery embolization (UAE). Our primary outcome was the rate of blood transfusion. Secondary outcomes were estimated intraoperative blood loss (BL), UAE, and admission to intensive care unit (ICU) and fertility preservation. Descriptive statistics were used to describe these variables. Main results and the role of chance For the 17 cases included, median CRL was 54.1 mm (range 40.0 - 85.7) and median gestational sac diameter was 52.7mm (range 41.0 – 82.7). Median gestational age based on CRL was 12 + 2 weeks (range 10 + 6 weeks and 15 + 2 weeks). Two (12%) women had a recurrent CSEP and 1 woman had a heterotropic pregnancy. On pre-operative ultrasound placental lacunae were recorded in 13 (76%) cases and colour Doppler score was ≥3 in 10 (59%) cases. A Shirodkar cervical suture was used in all cases, as per our protocol. It was successful in achieving haemostasis by tamponade in 13/17 (76%) cases. In the remaining 4 (24%) tamponade failed to achieve a complete haemostasis and UAE was required to control persistent arterial bleeding into the uterine cavity. Median BL at the time of surgery was 800 ml (range 250-2500) and 7/17 (41%) patients had a BL of &amp;gt; 1000 ml with 6/17 (35%) requiring blood transfusion. All four women who had UAE required admission to ICU. Three cases had a two-stage procedure with interval UAE to control the bleeding. All patients made a good postoperative recovery and no emergency hysterectomy was required. Three patients fell pregnant again and all pregnancies were normally sited. Limitations, reasons for caution Although this is the largest series of advanced CSEPs one limitation is its retrospective design and the relatively small number of cases. A second limitation is no women ≥ 16 weeks were included. Lastly, this study was conducted in a tertiary referral centre and results may not be widely replicable. Wider implications of the findings Surgical evacuation with a Shirodkar cervical suture and selective UAE is an effective treatment for advanced CSEPs and should be available to women who want to retain their fertility and avoid a hysterectomy. Pre-surgical planning and collaboration between gynaecologists and interventional radiologists is key in managing these high-risk women. Trial registration number not applicable

Placenta accreta spectrum: Is placental invasion real?

Background/Aim: The description of placenta accreta spectrum disorder (PAS) has undergone significant changes. However, its association with obstetric morbidity and mortality has become even more important. Therefore, we aimed to assess the histopathologic evaluation of PAS patients who underwent a hysterectomy. Methods: We conducted a retrospective study of all pathology reports from patients with peripartum hysterectomies at Sanliurfa Training and Research Hospital diagnosed with PAS. The study included 45 patients with a cesarean hysterectomy due to a preoperative placenta accreta spectrum disorder diagnosis. Hysterectomy specimens were evaluated based on placental invasion and myometrial defect at the site of the placenta. Results: Out of 45 patients diagnosed with placenta accreta spectrum disorder who underwent a hysterectomy, only 17 (37.8%) had a histological diagnosis supporting the placental invasion. The histological diagnosis was consistent in 20 (44.4%) patients, indicating that the placenta protruded from a uterine wall defect without placental invasion. In eighth (17.8%) patients, the histopathological diagnosis was consistent with a histologically normal placenta. Conclusion: The primary pathology of the disorder is variable, and the main issue is the association of the placenta with defective myometrium. Although a more alarming definition, such as invasion, should be avoided, PAS should not be underestimated due to its high mortality.

Multidisciplinary approach to the surgical management of interstitial ectopic pregnancy

To present a multidisciplinary approach to localize and resect suspected interstitial ectopic pregnancies. Interstitial ectopic pregnancies are distinct from eccentric intracavitary pregnancies and are defined by ultrasound-based criteria, including an empty uterine cavity, gestational sac located >1 cm from the cavity, thin overlying myometrium <5 mm, and the interstitial line sign. Case report. Academic medical center. Here, we present the case of a 28-year-old patient at 6 weeks of gestation by last menstrual period who presented to the emergency department with spotting. Initial pelvic ultrasound findings demonstrated a gestational sac and yolk sac that were believed to be located eccentrically within the uterine cavity. Follow-up imaging was performed 2 weeks later that revealed the pregnancy was located at the uterotubal junction and distinct from the endometrial cavity, consistent with an interstitial ectopic. The patient had ongoing light spotting with mild cramping, a benign clinical exam, and normal laboratory findings. Accurate assessment of pregnancy location is critical given that the mortality rate from interstitial pregnancies is twice that of other ectopics. In contrast, live birth rates for eccentric intracavitary pregnancies may be up to 69%, and some clinicians consider expectant management of asymptomatic patients in the first trimester. The patient was recommended for inpatient admission with expedited surgical management of interstitial ectopic pregnancy. On laparoscopic entry, the pregnancy was not well-visualized because it did not deform the uterine serosa. We present a surgical approach to suspected interstitial ectopic pregnancy that is not well-visualized at the time of laparoscopy. The following principles are explored: the use of multiple minimally invasive modalities (laparoscopy and hysteroscopy) to perform a thorough evaluation of the pregnancy location; incorporation of intraoperative ultrasound; temporary vessel ligation and injection of intramyometrial vasopressin; complete enucleation of the products of conception; and closure of the myometrial defect. We emphasize the benefits of a multidisciplinary approach for the localization and resection of interstitial ectopic pregnancy. This patient was discharged home in good condition with no complications.

Conservative surgical approach towards placenta accreta spectrum disorders for uterine preservation

ObjectiveWe previously described a technique for repair of the myometrial defect at repeat Caesarean section which increases residual myometrial thickness thereby potentially reducing future niche-related complications. Here we describe how this technique can be modified for use for placenta accreta spectrum disorders, in line with emerging evidence that this is more a disorder of myometrial deficiency than morbid adherence.DesignThe surgical performance of peripartum hysterectomy was compared with that of the modified technique in all women having repeat Caesarean delivery for placenta accreta spectrum disorder in a tertiary unit in Singapore between December 2019 and October 2021.MethodsModification of the original technique involved the systematic delivery of the placenta starting from its most posterior attachment after uterine exteriorization. This is followed by the identification, mobilization, and apposition of the boundaries of myometrial defects as described previously.ResultsTen women had Caesarean hysterectomy and ten had Caesarean section using the modified approach. Age and gestational age at delivery were similar for the two groups. Women in the modified technique group had had fewer prior Caesarean sections and had a lower body mass index. Operating time, estimated blood loss and need for transfusion were all lower in the myometrial repair group but without statistical significance. There were no visceral injuries in the repair group but there was one bladder injury in the hysterectomy group.ConclusionThe modified approach provides an effective alternative to peripartum hysterectomy with favourable surgical profile and allows uterine conservation with restoration of myometrial thickness.

Biomaterializing the advances in uterine tissue engineering.

The uterus is considered to be a unique wound-healing model and distinguished by the repeated shedding of the endometrium and self-traceless regeneration. Common curettage, cesarean section, and other operations often cause endometrial and myometrial defects and obstetric and gynecological complications, leading to a high demand for uterine repair or partial replacement. However, the structure and function of the uterus are complicated. Functional uterine tissue engineering requires highly specialized biomaterials with a natural extracellular microenvironment. Currently, no biomaterial can fully simulate the structural and biomechanical properties of the uterus. Many efforts have been made to develop highly functional materials and tissue structures that may provide uterine tissue engineering constructs for reducing obstetric and gynecological complications. Continuous efforts will likely facilitate the development of scalable cells and biomaterial technologies for clinical use. This review summarizes the recent applications of biomaterials and tissue engineering in rebuilding a portion of or the entire uterus.

Vasopressin Injection Purse-String Ectopic Resection (VIPER) Technique for Laparoscopic Management of Cornual Ectopic

<h3>Study Objective</h3> To describe the VIPER technique for the laparoscopic management of cornual ectopic pregnancy; a technique that minimizes blood loss and mitigates risk of conversion to laparotomy. <h3>Design</h3> Case series. <h3>Setting</h3> High-volume, academic and academic-affiliated medical centers. <h3>Patients or Participants</h3> All patients presenting with cornual ectopic pregnancy managed surgically. <h3>Interventions</h3> Laparoscopic cornual resection by five Minimally Invasive Gynecologic Surgeons. The VIPER technique utilizes four ports (umbilical, left lower quadrant, and ipsilateral right sided) and a 30-degree laparoscope. After obtaining visualization, dilute vasopressin is injected into the myometrium adjacent to the pregnancy. The affected fallopian tube is disconnected distally. A purse-string stitch with uni-directional barbed suture is placed circumferentially around the pregnancy and cinched. This stitch achieves hemostasis regardless of rupture status. The needle is left attached, and a wedge resection of the cornua is performed with an ultrasonic device. The myometrial defect is repaired with the remaining suture. <h3>Measurements and Main Results</h3> 17 patients underwent laparoscopic cornuectomy between 2012 to 2022, with 7 found to be ruptured. The mean patient age was 30 years (range 20-41), mean body mass index was 31.4kg/m² (range 22-52), and mean gestational age was 8 weeks 6 days (range 5 weeks 6 days to 11 weeks 1 day). Patient risk factors included history of prior sexually transmitted infection (3 patients), in vitro fertilization (1 patient), and prior ectopic pregnancy (1 patient). The other twelve patients had no risk factors. The mean operative time was 107 minutes (range 50-229), with mean estimated blood loss of 41mL for non-ruptured and 412mL for ruptured ectopic pregnancies. The mean hemoperitoneum identified was 1117mL, (range 50mL to 3325mL). There were no conversions to laparotomy. 70.6% of patients were discharged on the day of surgery. <h3>Conclusion</h3> The VIPER technique is feasible and effective for the management of both non-ruptured and ruptured cornual ectopic pregnancy.

Multidisciplinary Approach to the Surgical Management of Interstitial Ectopic Pregnancy

<h3>Study Objective</h3> We aim to present a multidisciplinary approach to localize and resect suspected interstitial ectopic pregnancy. <h3>Design</h3> Case report. <h3>Setting</h3> Academic medical center. <h3>Patients or Participants</h3> 28-year-old at 6 weeks gestation by last menstrual period presented to the emergency department with spotting. Although initial ultrasound suggested an eccentric intracavitary pregnancy, follow up imaging two weeks later showed that the pregnancy was located at the uterotubal junction, distinct from the endometrial cavity, and with thin overlying myometrium. This ruled in for suspected interstitial ectopic pregnancy. <h3>Interventions</h3> Given the patient's gestational age, vaginal spotting and pelvic pain, she was recommended to undergo surgical management. Upon laparoscopic entry, the pregnancy was not well visualized as it did not deform the uterine serosa. <h3>Measurements and Main Results</h3> We present a surgical approach to suspected interstitial ectopic pregnancy that is not well-visualized at the time of laparoscopy. The following principles are explored: 1) use of multiple minimally invasive modalities (laparoscopy and hysteroscopy) to perform thorough evaluation for pregnancy location, 2) incorporation of intraoperative ultrasound, 3) temporary vessel ligation and injection of intramyometrial vasopressin, 4) complete enucleation of products of conception, and 5) closure of the myometrial defect. <h3>Conclusion</h3> We emphasize the benefits of a multidisciplinary approach to localization and resection of interstitial ectopic pregnancy. This patient was discharged home in good condition with no complications.

8407 Interstitial Ectopic Pregnancy: A Case Series with Practical Tips for Surgical Management

<h3>Study Objective</h3> To review current treatment options for interstitial ectopic pregnancy (IP), with a focus on surgical treatments. To review outcomes of three surgically managed cases of IP. To demonstrate practical tips for success in laparoscopic management of IP. <h3>Design</h3> A case series presenting three cases of surgically managed IP with guided explanation of surgical intervention using video. <h3>Setting</h3> Academic affiliated community hospital. <h3>Patients or Participants</h3> The 3 cases of IP evaluated and treated over the past year were included in the study. <h3>Interventions</h3> Two patients underwent laparoscopic cornual resection of IP and one patient underwent emergent abdominal repair of ruptured IP. <h3>Measurements and Main Results</h3> Estimated blood loss (EBL) for laparoscopic management of 6-week IP with preoperative uterine artery embolization (UAE) was 20ml; length of post operative length of stay (LOS) was 1 day. EBL for 13-week IP without embolization was 50 ml, post op LOS was 0 days. EBL for ruptured IP repaired via open approach was 1000ml including hemoperitoneum, post operative LOS was 2 days. Beta hCG was trended once per week post operatively for all patients. Both patients undergoing laparoscopic resection had negative HCG by week 4. The patient with ruptured IP had negative hCG by week 8; however, she did not complete testing between week 5-7; at 4 weeks her hCG was 17. <h3>Conclusion</h3> IP is sometimes a difficult diagnosis to make; a high index of suspicion is necessary. Laparoscopic surgery for IP is achievable using similar techniques as laparoscopic myomectomy for limiting perioperative blood loss and repair of the myometrial defect; Ultrasonic scalpel, vasopressin, delayed absorbable barbed suture. IP can often be treated laparoscopically, however laparotomy may be necessary in unstable patients with advanced gestation. Further investigation is necessary to determine the best practice for surgical management of IP.

P-407 Pregnancy outcomes of different endometrial preparation in patients with a history of cesarean section

Abstract Study question To investigate the efficacies of three cycle regimens in women receiving frozen embryo transfer with a history of cesarean section(CS). Summary answer In women undergoing frozen embryo transfer with a history of CS, hormone replacement therapy for endometrial preparation was associated with a higher early miscarriage rate. What is known already Rates of CS are rising worldwide. Many women with a history of a CS delivery conceived through assisted reproductive technology (ART) are in need of frozen embryo transfer (FET) for their second progeny. Various protocols for endometrium preparation have been used to provide an optimal uterine environment for the transfer of thawed embryos, but the evidence supporting the superiority of one protocol over another is insufficient. Study design, size, duration A retrospective cohort study of patients (N = 6,159) with a history of CS who fulfilled the inclusion criteria were enrolled in the study from January 2014 to December 2019 at the CITIC-Xiangya Hospital of Reproduction and Genetics. Participants/materials, setting, methods Reproductive outcomes of patients in the natural cycle （NC） (n = 4,306) versus hormone replacement therapy（HRT） (n = 1,007) versus gonadotropin-releasing hormone agonist （GnRH-a） + HRT groups (n = 846) were compared. Multiple logistic regression analyses were performed to investigate the potential confounding factors. Main results and the role of chance The unadjusted odds of the miscarriage rate of singleton pregnancies were also significantly higher in the hormone replacement therapy compared with the natural cycle (25.5% versus 20.4%, respectively). After adjusting for possible confounding factors, the early miscarriage rate and the miscarriage rate of singleton pregnancies remained significantly higher in the hormone replacement therapy than the natural cycle. The clinical pregnancy rates in the hormone replacement therapy, hormone replacement therapy and treatment with gonadotropin-releasing hormone agonist of women with a history of cesarean section was 48.8%, 48% and 47.1%, respectively, and the live birth rates were 37%, 34.1% and 35.7%, respectively. Limitations, reasons for caution This study is limited by its retrospective design. Furthermore, the detailed ultrasound information on uterine myometrial defects, complications related to CS and the number of previous CSs were unavailable in our study. Another limitation is that pregnancy-related complications and neonatal outcomes were not analyzed. Wider implications of the findings Our study could help physicians improve their understanding of the impact of different protocols on pregnancy outcomes in patients with a history of CS. Prospective randomized trials should be conducted to assess the efficacy of endometrial preparation protocols for FET in women with a history of CS. Trial registration number not applicable