A comprehensive review of Asherman's syndrome: causes, symptoms and treatment options

Intrauterine infusion of autologous endometrial stem cells for the treatment of moderate and severe intrauterine adhesions: a before-and-after study

BACKGROUND

Intrauterine adhesions (IUAs) can easily cause female infertility or recurrent abortion, but there is still no effective treatment to improve the pregnancy and live birth rates in patients with IUAs. In recent years, great advances have been made in stem cell therapy; however, additional clarity is needed on the clinical efficacy of endometrial stem cells in the treatment of IUAs.

MATERIALS AND METHODS

Fifteen patients with moderate-to-severe IUAs were included in the study at Xiangtan Central Hospital from 2018 to 2020. Patients were treated with endometrial stem cells and sodium hyaluronate gel by intrauterine perfusion in combination with estrogen and acetylsalicylic acid support therapy. Then, data on the pregnancy and live birth status was collected within two years after treatment. To explore the underlying mechanism, primary endometrial stem cells from healthy individuals and IUA patients, as well as fifth-generation endometrial stem cells from IUA patients, were further conducted with RNA sequencing to screen for differentially expressed genes, which were subsequently used for functional enrichment analysis.

RESULTS

After endometrial stem cell transplantation into the uterine cavity, the American Fertility Society scores of all patients decreased, and hysteroscopy revealed an improvement in the uterine condition and a reduction in adhesion symptoms. The total pregnancy rate of the 15 patients was 60.0% and the live birth rate was 53.3%. In addition, RNA sequencing analysis revealed that the cytokine - cytokine receptor interaction was associated with endometrial repair by endometrial stem cells.

CONCLUSIONS

Intrauterine infusion of autologous endometrial stem cells is highly effective for patients with moderate-to-severe IUA, and is a promising treatment strategy.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, CHICTR1800016769, Registered 22 June 2018- Retrospectively registered, https://www.chictr.org.cn/showproj.html?proj=27042 .

Effect of hysteroscopic adhesiolysis for mild intrauterine adhesions on live birth rate following embryo transfer: a retrospective cohort study

BACKGROUND

Numerous studies have demonstrated that the presence of IUAs can have detrimental effects on female reproductive function, potentially leading to infertility. Hysteroscopic adhesiolysis is widely regarded as the primary treatment for IUAs. A 2021 consensus development study on the top 10 research priorities for the future of infertility suggested that the impact on live birth rates after surgical treatment of mild IUAs is uncertain.

MATERIALS AND METHODS

The study was a retrospective cohort study that included 442 patients who were diagnosed with mild IUAs and underwent embryo transfer (fresh or frozen embryo) from January 2017 to December 2023 at a University-based reproductive medical center. Patients were divided into two groups according to whether underwent hysteroscopic adhesiolysis. The non-surgical group consisted of 204 patients, while the surgical group consisted of 238 patients. all patients underwent fresh or frozen embryo transfer. We compared the pregnancy outcomes and obstetric outcomes of the first embryo transfer after diagnosis or surgery of IUAs between the two groups. The main outcome measure is live birth rates. Between-group variances were evaluated using either the Pearson χ² test or the t-test. Multiple logistic regression analyses were applied to control for potential confounding effects.

RESULTS

There were no significant differences in live birth rates of the non-surgical group and the surgical group(45.1% versus 42.0%,aOR,0.824;95%CI,0.558-1.217;P,0.330).All other pregnancy indicators showed no significant difference between the groups either.

CONCLUSION

Hysteroscopic adhesiolysis does not significantly improve the live birth rates in patients with mild IUAs. Therefore, for patients with mild IUAs, it is recommended to prioritize expectant treatment.

CLINICAL TRIAL NUMBER

Not applicable.

Comparison of hysteroscopic adhesiolysis with electrosurgery instrument or hysteroscopic scissors in the treatment of intrauterine adhesions of infertile or recurrent pregnancy loss women

OBJECTIVE

To investigate pregnancy outcomes following hysteroscopic adhesiolysis (HA) in patients with recurrent pregnancy loss (RPL) or infertility.

DESIGN

Retrospective cohort study.

SETTING

University-affiliated hospital.

SUBJECTS

According to the inclusion and exclusion criteria of this study, finally, a total of 461 subjects were included.

INTERVENTIONS

HA performed using either an electrosurgical instrument or hysteroscopic scissors.

MAIN OUTCOME MEASURES

Pregnancy outcomes post-HA.

RESULTS

A total of 461 patients were included in the study, with follow-up periods ranging from 1 to 6 years. The mean age was 29.48 ± 3.25 years. Hysteroscopic scissors demonstrated greater efficiency in restoring the uterine cavity compared to electrosurgical instruments (88.1% vs. 80.0%, p = 0.025). Post-HA, the pregnancy rate was approximately 75.3% (347/461), with a live birth rate of 55.9% (251/449). No significant differences were found between the electrosurgical instrument and hysteroscopic scissors groups regarding improvements in menstrual flow or fertility outcomes (all p > 0.05). Kaplan-Meier time-dependent cumulative curves for pregnancy and live birth rates after HA indicated that over 50% of patients achieved pregnancy within one year, with the pregnancy rate plateauing at 2 years and the live birth rate at 3 years.

CONCLUSION

Our findings suggest that HA can improve fertility outcomes for patients with RPL or infertility within 2 to 3 years following surgery. Hysteroscopic scissors proved more effective than electrosurgical instruments in restoring the uterine cavity, although no differences were observed between the techniques in terms of menstrual flow or fertility improvements. All in all, our study suggests that standardized HA procedures, the implementation of proactive intraoperative and postoperative measures to prevent the recurrence of intrauterine adhesions (IUA), and an active conception plan following HA are key factors in improving reproductive outcomes for these patients with RPL or infertility.

3D bioprinting technology innovation in female reproductive system

Several diseases affect the female reproductive system, and both disease factors and treatments impact its integrity and function. Consequently, understanding the mechanisms of disease occurrence and exploring treatment methods are key research focuses in obstetrics and gynecology. However, constructing accurate disease models requires a microenvironment closely resembling the human body, and current animal models and 2D in vitro cell models fall short in this regard. Thus, innovative in vitro female reproductive system models are urgently needed. Additionally, female reproductive system diseases often cause tissue loss, yet effective tissue repair and regeneration have long been a bottleneck in the medical field. 3D bioprinting offers a solution by enabling the construction of implants with tissue repair and regeneration capabilities, promoting cell adhesion, extension, and proliferation. This helps maintain the long-term efficacy of bioactive implants and achieves both structural and functional repair of the reproductive system. By combining live cells with biomaterials, 3D bioprinting can create in vitro 3D biomimetic cellular models, facilitating in-depth studies of cell-cell and cell-extracellular microenvironment interactions, which enhances our understanding of reproductive system diseases and supports disease-specific drug screening. This article reviews 3D bioprinting methods and materials applicable to the female reproductive system, discussing their advantages and limitations to aid in selecting optimal 3D bioprinting strategies. We also summarize and critically evaluate recent advancements in 3D bioprinting applications for tissue regeneration and in vitro disease models and address the prospects and challenges for translating 3D bioprinting technology into clinical applications within the female reproductive system.

The application of tissue engineering strategies for uterine regeneration

Uterine injuries, particularly damages to endometrium, are usually associated with abnormal menstruation, recurrent miscarriage, pregnancy complications, and infertility. Tissue engineering using cell-based, biomolecule-based, or biomaterial and scaffold-based strategies has emerged as a novel and promising approach for uterine regeneration. Stem cells, biomolecules, and porous scaffolds used alone or, very often, used in combination as a more effective treatment means have shown great potential in promoting uterine regeneration. The reported preclinical studies have indicated that appropriate tissue engineering strategies could safely and effectively reconstruct not only endometrium but also partial or even the whole uterine structure. However, the progress in the uterine regeneration area is slow in comparison to that of regenerating many other body tissues and hence it still remains a great challenge to apply uterine tissue engineering for clinical applications. In this review, conventional treatments for uterine-related diseases are briefly reviewed and discussed first. Subsequently, tissue engineering strategies (cell-based, biomolecule-based, biomaterial and scaffold-based, or their combinations) for uterine repair in preclinical studies and clinical trials are presented and analyzed. Finally, the challenges and perspectives in uterine regeneration are pointed and discussed. Despite various limitations and obstacles, the tissue engineering approach is viable and holds high promise for uterine regeneration.

Progress in Polysaccharide-Based Hydrogels for Preventing Postoperative Adhesions: A Review

Postoperative adhesions are common complications following surgery, often accompanied by pain and inflammation that significantly diminish patients' quality of life. Moreover, managing postoperative adhesions incurs substantial cost, imposing a considerable financial burden on both patients and healthcare systems. Traditional anti-adhesion materials are confronted with limitations, such as inadequate tissue adherence in a moist environment and poor degradability, underscoring the urgent need for more effective solutions. Recently, polysaccharide-based hydrogels have received considerable attention for their potential in preventing postoperative adhesions. The hydrogels not only facilitate wound healing but also effectively reduce inflammation, providing a promising approach to preventing postoperative adhesions. This review provides an extensive analysis of the progress made in the development of polysaccharide-based hydrogels for postoperative anti-adhesion therapy. It highlights their principal benefits, outlines future research trajectories, and addresses the ongoing challenges that need to be overcome.

Multi-parametric MRI combined with radiomics for the diagnosis and grading of endometrial fibrosis

PURPOSE

To evaluate the application of multi-parametric MRI (MP-MRI) combined with radiomics in diagnosing and grading endometrial fibrosis (EF).

METHODS

A total of 74 patients with severe endometrial fibrosis (SEF), 41 patients with mild to moderate fibrosis (MMEF) confirmed by hysteroscopy, and 40 healthy women of reproductive age were prospectively enrolled. The enrolled data were randomly stratified and divided into a train set (108 cases: 28 healthy women, 29 with MMEF, and 51 with SEF) and a test set (47 cases: 12 healthy women, 12 MMEF and 23 SEF) at a ratio of 7:3. All participants underwent T2 and DWI sequence scans. By freely delineating the volume of interest (VOI) of the endometrium in three subgroups, radiomic features were extracted and selected. Two feature selection methods and four machine learning (ML) classifiers were combined in pairs to establish five prediction models [model1 (T2 + ADC + clinical data), model2 (T2 + ADC), model3 (T2), model4 (ADC), and model5 (clinical data)], resulting in a total of 40 classification models. The predictive performance of all models was evaluated using the area under the curve (AUC), F1-score, and accuracy (ACC).

RESULTS

The "UFS-LR" model, which combined unsupervised feature selection (UFS) with the logistic regression (LR) classifier, performed the best, with an average AUC of 0.92 on the test set. Among the five models constructed via UFS-LR, model1 exhibited the best performance, with average AUC, F1-score, and ACC values of 0.92, 0.80, and 0.81, respectively. T2-related features were the most significant in distinguishing fibrosis levels, with T2_wavelet-LLL_gldm_DependenceVariance being the most important characteristic among them.

CONCLUSION

MP-MRI radiomics analysis using ML has excellent performance in grading EF. This approach is non-invasive and has the potential to reduce the reliance on hysteroscopy.

A New Intrauterine Adhesions Classification System: The "Loddo Score"

Intrauterine adhesions (IUAs) and Asherman's syndrome (AS) have been recognized medical conditions since the late 19th and mid-20th centuries. Multiple classification systems have been proposed to better understand their severity and implications. This article aims to provide a comprehensive overview of the existing classifications for IUAs and introduces the Loddo scoring system, a novel approach for classifying these conditions. The Loddo scoring system is unique in amalgamating the strengths of previous classifications while emphasizing the importance of ultrasonographic endometrial thickness. This new system integrates various clinical parameters, offering a holistic representation of IUAs in clinical presentation and underlying structural changes. The Loddo scoring system presents a refined approach to understand and manage IUAs, providing a precise prognosis evaluation. Bridging the diagnostic and therapeutic divide seen in past systems, it offers promise for reshaping the landscape of diagnosis and treatment in women's health. Further research and validation are essential to assess its broad clinical applicability.

Reliability of an Electronic Uterine Diagram to Standardize Intrauterine Adhesion Scoring

STUDY OBJECTIVE

To study the inter-rater reliability of an electronic complementary uterine diagram (electronic American Fertility Society [eAFS] freely available at https://bit.ly/eAFS-score) in comparison with the conventional American Fertility Society (cAFS) intrauterine adhesion (IUA) scoring system. As a secondary aim, we wanted to assess the intra-rater reliability of these tools.

DESIGN

This was an observational cross-over study with a nested test-retest design.

SETTING

Self-identified gynecologists who performed diagnostic hysteroscopy as part of their routine practice were asked to score IUA on 7 preselected videos using both cAFS and eAFS tools in 2 separate rounds. The order of use of tools was determined at random. Gynecologists who agreed to be involved in a third round were asked to use the tool they were allocated to in the first round to assess intra-rater variability.

PATIENTS

No patients were recruited for the purpose of this study.

MEASUREMENTS AND MAIN RESULTS

Inter-rater agreement between evaluators when using eAFS and cAFS for IUA scoring. Overall, the inter-rater agreement was fair (0.25; confidence interval [CI], 0.17-0.34) for cAFS and moderate (0.53; CI, 0.48-0.58) for the eAFS tool. The biggest difference between both tools was seen in the "extent of cavity involved" component, which was fair (0.28; CI, 0.21-0.35) vs substantial (0.71; CI, 0.64-0.78) for cAFS vs eAFS, respectively. Moreover, agreement coefficients were comparable among "expert" and "non-expert" evaluators with the use of the eAFS tool. In addition, intra-rater perfect agreement was higher with the use of eAFS than cAFS (38% vs 32.5%).

CONCLUSION

The current AFS IUA scoring system has fair inter-rater agreement. However, using a complementary electronic uterine diagram increased this agreement from fair to moderate overall and from fair to substantial in the "extent of adhesions" domain of the tool. The use of the electronic diagram also improved inter-rater agreement among non-experts making it comparable with that of experts.

Diagnostic and therapeutic hysteroscopy in Ethiopia: a retrospective study on practice and outcomes

BACKGROUND

Hysteroscopy is considered the standard for evaluating the uterine cavity. Limited data exists regarding hysteroscopy in Ethiopia. Therefore, the objective of the study was to describe the diagnostic and operative hysteroscopic procedures at St. Paul's Hospital.

METHODOLOGY

A three-year retrospective descriptive study examined patients who underwent diagnostic and therapeutic hysteroscopy at the Center for Fertility and Reproductive Medicine, St. Paul's Hospital Millennium Medical College in Addis Ababa, Ethiopia, from June 2018 to June 2021. Descriptive statistics were employed to summarize the findings observed during the hysteroscopy procedures.

RESULT

A total of 328 patient records underwent review and analysis in the study. The mean participant age was 31.9 years (31.9 ± 5.1 years), with about 81.4% being nulliparous. Primary infertility (48.5%) was the leading indication for hysteroscopic evaluation, followed by secondary amenorrhea (18%), secondary infertility (17.4%), and abnormal uterine bleeding (8.8%). Concerning hysteroscopic procedures, 6.1% of participants exhibited no uterine cavity abnormalities. Primary hysteroscopy findings comprised intracavitary adhesions (48.2%), endometrial polyps (18%), and submucosal myomas (9%). Adhesiolysis stood out as the foremost surgical procedure, conducted in 48.2% of patients, followed by polypectomy in 20.7%, and fibroid removal in 9%. The complication rate was 2.4%, exclusively during operative hysteroscopy, with uterine perforation observed in six patients.

CONCLUSION

Our hysteroscopic evaluation was predominantly requested for primary infertility cases, with secondary amenorrhea, secondary infertility, and abnormal uterine bleeding also being commonly encountered indications. Adhesiolysis was the leading intervention during hysteroscopy, while uterine perforation was the main complication. The hysteroscopy procedures exhibited a strong safety profile, with few complications noted. Future studies should address factors affecting outcomes in diagnostic and operative hysteroscopy, and common factors linked to intrauterine adhesions.

A new uterine endometrium preservation hysteroscopic myomectomy: Introduction of improved procedures and a retrospective analysis of 94 cases

Objective

To reduce the damage of uterine endometrium caused during hysteroscopic myomectomy (HM) for reproductive aged patients, a new uterine endometrium preservation hysteroscopic myomectomy (UEP-HM) has been developed. In this study, we introduced this technique with comparing to the conventional hysteroscopic myomectomy (C-HM).

Study Design

The data from 94 patients aged 42 or younger who underwent HM (38 cases with UEP-HM and 56 cases with C-HM) for treating single Type 1 or Type 2 submucosal leiomyoma (SL) were analysed retrospectively for comparing the characteristics of both patient and target SL. In this process, we defined the operation time 60 min or over as the longtime operation (LTO) and the SM sized 3 cm or over as the large submucosal leiomyoma (LSL) for detecting the influential factors, including this procedure, on the difficulty of HM. For assisting the prediction of operation time (OT), we investigated the relationship between the OT and the cube of average diameter (AD) of target SL referring with some past reports.

Results

Although when comparing UEP and control groups, parity, AD, the number of patients with Type 2 SL, OT, and the number of infertile patients showed significant difference, in the multivariate analysis only LSL showed the significant influence on the possibility of LTO. Next, we compared OT/Cube of AD, which calculated by dividing OT by the cube of AD for evaluating OT from the target SL size and confirmed that there was no difference in those 2 groups (3.7 ± 3.0 (95 %CI: 0.9 - 13.3, n = 38) vs. 3.9 ± 3.2 (95 %CI: 0.4 - 17.3, n = 56), p = 0.79).

Conclusions

The new UEP-HM can become an alternative method of C-HM without procedure-specific difficulty. In the future, to investigate the prognosis of this procedure, more patients and further analyses should be accumulated.

Effectiveness of degradable polymer film in the management of severe or moderate intrauterine adhesions (PREG-2): a randomized, double-blind, multicenter, stratified, superiority trial

OBJECTIVE

To study the effectiveness of a new intrauterine degradable polymer film (Womed Leaf) in the management of moderate to severe intrauterine adhesions (IUA).

DESIGN

PREG-2 study was a multicenter, double-blind, randomized, controlled, stratified, two-arm superiority clinical trial conducted in 16 centers in seven countries.

SETTING

Not applicable.

PATIENT(S)

Patients ≥18 years scheduled for hysteroscopic adhesiolysis because of symptomatic severe or moderate adhesions (according to American Fertility Society [AFS] IUA score) were considered eligible for the study.

INTERVENTION(S)

After adhesiolysis, patients were randomized at a 1:1 ratio to either have a Womed Leaf film inserted (intervention group) or not (control group).

MAIN OUTCOME MEASURE(S)

The primary effectiveness endpoint of the study was the change in AFS IUA score on second-look hysteroscopy (SLH), assessed by an independent evaluator, and compared with baseline. Information on the rate of no IUA and responder rate was collected as secondary effectiveness outcomes, while reported adverse events and patient-reported outcomes as safety and tolerability measures.

RESULT(S)

Between October 26, 2021, and September 28, 2023, a total of 160 women were randomized (Womed Leaf: n = 75 and controls: n = 85). The reduction in IUA AFS score on SLH was significantly higher in the intervention compared with the control group (mean 5.2 ± 2.8 vs. 4.2 ± 3.2). Similarly, the absence of adhesions on SLH was significantly higher in the intervention group (41% vs. 24%; odds ratio, 2.44; confidence interval, 1.161-5.116). None of the reported adverse events were serious or considered related to the device.

CONCLUSION(S)

Womed Leaf is effective and safe in the management of symptomatic severe or moderate IUAs.

CLINICAL TRIAL REGISTRATION NUMBER

Clinicaltrials.gov identifier: NCT04963179.

Mechanistic insights into intrauterine adhesions

Intrauterine adhesions (IUA), also known as Asherman's syndrome, arise from damage to the basal layer of the endometrium, frequently caused by intrauterine interventions. This damage leads to nonregenerative healing of endometrium resulting in replacement by fibrous connective tissue, which bring about the adherence of opposing endometrium to render the uterine cavity and/or cervical canal partially or completely obliterated. IUA is a common cause of the refractory uterine infertility. Hysteroscopy is the gold standard for diagnosis of IUA. However, the method of accurately predicting the likelihood of achieving a live birth in the future remains established. Classical treatments have shown limited success, particularly in severe cases. Therefore, utilizing new research methods to deepen the understanding of the pathogenesis of IUA will facilitate the new treatment approaches to be found. In this article we briefly described the advances in the pathogenesis of IUA, with focus on inflammation and parenchymal cellular homeostasis disruption, defects in autophagy and the role of ferroptosis, and we also outlined the progress in IUA therapy.

Treatment of intrauterine adhesions and subsequent pregnancy outcomes in an in vitro fertilization population

BACKGROUND

Asherman syndrome refers to the presence of intrauterine adhesions, which have clinical implications, including infertility. There are few studies assessing the effect of serial hysteroscopies for adhesiolysis on reproductive and pregnancy outcomes among women who subsequently undergo in vitro fertilization, and none have looked at maternal, neonatal, or placental pregnancy complications.

OBJECTIVE

This study aimed to explore the effect of hysteroscopic adhesiolysis among a cohort of patients who subsequently undergo in vitro fertilization.

STUDY DESIGN

This was a retrospective cohort study of all patients who underwent hysteroscopic adhesiolysis for intrauterine adhesions at our center between 2005-2020 and subsequently attempted conception by in vitro fertilization. A control group of patients who underwent in vitro fertilization for nonuterine factor infertility and had no history of intrauterine adhesions was chosen for comparison.

RESULTS

There were 691 patients included in this study, of whom 168 were intrauterine adhesion cases. The implantation rate (41.3% in both groups) and live birth rate (adjusted relative risk, 0.93 [95% confidence interval, 0.76-1.14]) were not statistically different between cases and controls. When grouped by number of previous adhesiolysis surgeries, patients who underwent ≥2 adhesiolysis surgeries had a lower live birth rate than controls (adjusted relative risk, 0.53 [95% confidence interval, 0.28-0.99]). Endometrial thickness before the transfer was significantly reduced in cases vs controls (8.23 vs 10.25 mm; adjusted relative risk, 0.84 [95% confidence interval, 0.78-0.90]). Adverse placental outcomes, including placenta accreta spectrum, placenta previa, or vasa previa, were significantly more likely to occur in cases than controls (adjusted relative risk, 2.08 [95% confidence interval, 1.25-3.46]). When grouped by the number of adhesiolysis surgeries, the risk appeared to increase as the number of prior surgeries increased. This is likely because of the increased severity of these adhesions.

CONCLUSION

Overall, patients with a history of treated intrauterine adhesions have the same live birth rate as patients undergoing in vitro fertilization for nonuterine factor indications. However, the subgroup of patients who require multiple surgeries for correction of intrauterine adhesions had a lower live birth rate after in vitro fertilization than controls. Patients with a history of treated intrauterine adhesions are at significantly greater risk of placenta accreta syndrome disorder than control patients who underwent in vitro fertilization for nonuterine factor indications.

Engineered extracellular vesicles for tissue repair and regeneration

Extracellular vesicles (EVs) are heterogeneous membrane-like vesicles secreted by living cells that are involved in many physiological and pathological processes and act as intermediaries of intercellular communication and molecular transfer. Recent studies have shown that EVs from specific sources regulate tissue repair and regeneration by delivering proteins, lipids, and nucleic acids to target cells as signaling molecules. Nanotechnology breakthroughs have facilitated the development and exploration of engineered EVs for tissue repair. Enhancements through gene editing, surface modification, and content modification have further improved their therapeutic efficacy. This review summarizes the potential of EVs in tissue repair and regeneration, their mechanisms of action, and their research progress in regenerative medicine. This review highlights their design logic through typical examples and explores the development prospects of EVs in tissue repair. The aim of this review is to provide new insights into the design of EVs for tissue repair and regeneration applications, thereby expanding their use in regenerative medicine.

A novel intrauterine estrogen-releasing system for preventing the postoperative recurrence of intrauterine adhesion: a multicenter randomized controlled study

BACKGROUND

Transcervical resection of adhesions (TCRA) is the standard treatment for intrauterine adhesion (IUA). Previous studies have shown that postoperative oral estrogen or an intrauterine physical barrier could reduce the recurrence of IUA by promoting the proliferation of the endometrium or inhibiting the reformation of adhesions. Our team designed an intrauterine stent that can release estrogen within the uterine cavity slowly. In this study, we aimed to investigate the efficacy and safety of the estrogen-releasing intrauterine system in preventing the recurrence of moderate to severe IUA.

METHODS

This was a multicenter prospective randomized controlled 2-arm parallel trial that included patients who were diagnosed with moderate to severe IUA and who received TCRA. A total of 250 patients were randomly assigned, at a 1:1 ratio, to receive the intrauterine estrogen-releasing system or a Foley catheter balloon combined with oral estrogen therapy after surgery. The primary outcome was the rate of adhesion reduction in the two groups. The secondary outcomes included endometrial thickness at the ovulation period, menstrual improvement rates, and other reported adverse events during follow-up.

RESULTS

The average daily drug release amount for all the tested stents was 0.21 mg/day. At 60 days postoperatively, the rate of adhesion reduction was significantly greater in the experimental group than in the control group (93.33% vs. 58.56%, p < 0.001). The endometrium of the experimental group was thicker than that of the control group (p < 0.001). Consistently, the rate of improvement in menstruation was greater in the experimental group than in the control group (p = 0.010). No grade 3-4 adverse events were found in the two groups during the 1-year follow-up.

CONCLUSIONS

In the cohort of patients with moderate to severe IUA, the intrauterine estrogen-releasing system was more effective at reducing adhesion than traditional oral estrogen combined with an intrauterine Foley catheter after TCRA. This novel intrauterine system provides a new option for the management of IUA after surgery.

TRIAL REGISTRATION

The registration number is NCT04972032. Date of registration: August 15, 2021.

Injectable, degradable, and mechanically adaptive hydrogel induced by L-serine and allyl-functionalized chitosan with platelet-rich plasma for treating intrauterine adhesions

The integration of barrier materials with pharmacological therapy is a promising strategy to treat intrauterine adhesions (IUAs). However, most of these materials are surgically implanted in a fixed shape and incongruence with the natural mechanical properties of the uterus, causing poor adaptability and significant discomfort to the patients. Herein, an injectable, biodegradable, and mechanically adaptive hydrogel loaded with platelet-rich plasma (PRP) is created by L‑serine and allyl functionalized chitosan (ACS) to achieve efficient, comfortable, and minimally invasive treatment of IUAs. L‑serine induces fast gelation and mechanical reinforcement of the hydrogel, while ACS introduces, imparting a good injectability and complaint yet strong feature to the hydrogel. This design enables the hydrogel to adapt to the complex geometry and match the mechanical properties of the uterine. Moreover, the hydrogel exhibits proper degradability, sustained growth factors (GFs) of PRP release ability, and good biocompatibility. Consequently, the hydrogel shows promising therapeutic efficacy by reducing collagen fiber deposition and facilitating endometrium cell proliferation, thereby restoring the fertility function of the uterus in an IUAs model of rats. Accordingly, the combination of L‑serine and ACS-induced hydrogel with such advantages holds great potential for treating IUAs. STATEMENT OF SIGNIFICANCE: This research introduces a breakthrough in the treatment of intrauterine adhesions (IUAs) with an injectable, biodegradable and mechanically adaptive hydrogel using L‑serine and allyl functionalized chitosan (ACS). Unlike traditional surgical treatments, this hydrogel uniquely conforms to the uterus's geometry and mechanical properties, offering a minimally invasive, comfortable, and more effective solution. The hydrogel is designed to release growth factors from platelet-rich plasma (PRP) sustainably, promoting tissue regeneration by enhancing collagen fiber deposition and endometrium cell proliferation. Demonstrated efficacy in a rat model of IUAs indicates its great potential to significantly improve fertility restoration treatments. This advancement represents a significant leap in reproductive medicine, promising to transform IUAs treatment with its innovative approach to achieving efficient, comfortable, and minimally invasive therapy.

Transplantation of acellular amniotic membrane seeded with adipose-derived mesenchymal stem cells in a rat model of intrauterine adhesion

Objective

This study aimed to investigate the role of acellular amniotic membrane (AAM) loaded with adipose-derived mesenchymal stem cells (ADSCs) for the treatment of intrauterine adhesion.

Methods

One hundred twenty female Spargue-Dawley rats were randomly divided into four groups: sham operation group (the uterus was picked out and incised without treatment), intrauterine adhesion group, the experimental group treated with AAM, and experimental group treated with AAM loaded with ADSCs. Histological and immunohistochemical analysis were performed on 3, 7, and 14 days after surgery to evaluate the degree of uterine fibrosis and regeneration of injured endometrium. RNA sequencing and real-time PCR were used to explore the potential mechanism by which ADSCs modulated immune response and promoted endometrial regeneration.

Results

On 14 days after surgery, the endometrial thickness, number of glands, and degree of fibrosis reduction in the ADSCs/AAM group was higher than those in the AAM group, and similar to the sham operation group. RNA sequencing analysis showed that ADSCs can modulate local immune responses and promote the formation of functional endometrium. Meanwhile, we found that ADSCs significantly decreased the levels of pro-inflammatory cytokines (TNF-α and IL-1β) and increased the levels of anti-inflammatory cytokines (bFGF and IL-6).

Conclusion

Our results demonstrated that AAM loaded with ADSCs can result in the regeneration of injured endometrium and fibrosis reduction. Meanwhile, ADSCs also regulated the immune microenvironment, which was beneficial to functional endometrial recovery.

Injectable alginate-based zwitterionic hydrogels promoting endometrial repair and restoring fertility

The development of novel therapeutic approaches to facilitate endometrial repair and regeneration while preventing adhesion recurrence is a crucial research objective aimed at enhancing clinical outcomes for women with intrauterine adhesions (IUA). In this study, we introduced an injectable Alg-GMA/PTSB zwitterionic hydrogel, characterized by excellent biocompatibility, anti-protein adsorption properties, and biodegradability. In a rat model, the hydrogel significantly promoted the regeneration and angiogenesis of damaged endometrial tissue, leading to improved recovery of epithelial cells, glands, proliferation, and vascularization. Furthermore, it exhibited the ability to suppress cellular apoptosis and collagen deposition, thereby mitigating fibrosis. Additionally, the hydrogel restored the expression of estrogen/progesterone receptors and endometrial receptivity markers, contributing to enhanced embryo implantation and fertility. These findings underscore the potential of the hydrogel as a promising therapeutic strategy for addressing endometrial injury, reducing fibrosis, restoring fertility, and ultimately improving outcomes for women with IUA.

The efficacy of early office hysteroscopy in preventing intrauterine adhesions after abortion: a randomized controlled trial

BACKGROUND

Intrauterine adhesions (IUA) are a challenging clinical problem in reproductive infertility. The most common causes are intrauterine surgery and abortions. We aimed to investigate whether early second-look office hysteroscopy can prevent IUA.

METHODS

A single-center, prospective, two-armed, randomized controlled trial was designed to explore the efficacy of early office hysteroscopy after first-trimester induced abortion (suction dilatation and curettage [D&C]) and to further analyze fertility outcomes. Women aged 20-45 years undergoing suction D&C and desiring to conceive were recruited. Between October 2019 and September 2022, 66 women were enrolled, of whom 33 were allocated to group A (early hysteroscopy intervention). The women in intervention group A were planned to receive 2 times of hysteroscopies (early and late). In group B, women only underwent late (6 months post suction D&C) hysteroscopy.

RESULTS

The primary outcome was the IUA rate assessed using office hysteroscopy 6 months after artificial abortion. Secondary outcomes included menstrual amount/durations and fertility outcomes. In intervention group A, 31 women underwent the first hysteroscopy examination, and 15 completed the second. In group B (late hysteroscopy intervention, 33 patients), 16 completed the hysteroscopic exam 6 months after an artificial abortion. Twenty-one women did not receive late hysteroscopy due to pregnancy. The IUA rate was 16.1% (5/31) at the first hysteroscopy in group A, and no IUA was detected during late hysteroscopy. Neither group showed statistically significant differences in the follow-up pregnancy and live birth rates.

CONCLUSIONS

Early hysteroscopy following suction D&C can detect intrauterine lesions. IUA detected early by hysteroscopy can disappear on late examination and become insignificant for future pregnancies. Notably, the pregnancy outcomes showed a favorable trend in the early hysteroscopy group, but there were no statistically significant differences.

TRIAL REGISTRATION

ClinicalTrials.gov , ID: NCT04166500. Registered on 2019-11-10. https://clinicaltrials.gov/ct2/show/NCT04166500 .

Incorporation of Decidual Stromal Cells Derived Exosomes in Sodium Alginate Hydrogel as an Innovative Therapeutic Strategy for Advancing Endometrial Regeneration and Reinstating Fertility

Intrauterine adhesion (IUA) stands as a prevalent medical condition characterized by endometrial fibrosis and scar tissue formation within the uterine cavity, resulting in infertility and, in severe cases, recurrent miscarriages. Cell therapy, especially with stem cells, offers an alternative to surgery, but concerns about uncontrolled differentiation and tumorigenicity limit its use. Exosomes, more stable and immunogenicity-reduced than parent cells, have emerged as a promising avenue for IUA treatment. In this study, a novel approach has been proposed wherein exosomes originating from decidual stromal cells (DSCs) are encapsulated within sodium alginate hydrogel (SAH) scaffolds to repair endometrial damage and restore fertility in a mouse IUA model. Current results demonstrate that in situ injection of DSC-derived exosomes (DSC-exos)/SAH into the uterine cavity has the capability to induce uterine angiogenesis, initiate mesenchymal-to-epithelial transformation (MET), facilitate collagen fiber remodeling and dissolution, promote endometrial regeneration, enhance endometrial receptivity, and contribute to the recovery of fertility. RNA sequencing and advanced bioinformatics analysis reveal miRNA enrichment in exosomes, potentially supporting endometrial repair. This finding elucidates how DSC-exos/SAH mechanistically fosters collagen ablation, endometrium regeneration, and fertility recovery, holding the potential to introduce a novel IUA treatment and offering invaluable insights into the realm of regenerative medicine.

Injectable "Homing-Like" Bioactive Short-Fibers for Endometrial Repair and Efficient Live Births

The prevalence of infertility caused by endometrial defects is steadily increasing, posing a significant challenge to women's reproductive health. In this study, injectable "homing-like" bioactive decellularized extracellular matrix short-fibers (DEFs) of porcine skin origin are innovatively designed for endometrial and fertility restoration. The DEFs can effectively bind to endometrial cells through noncovalent dipole interactions and release bioactive growth factors in situ. In vitro, the DEFs effectively attracted endometrial cells through the "homing-like" effect, enabling cell adhesion, spreading, and proliferation on their surface. Furthermore, the DEFs effectively facilitated the proliferation and angiogenesis of human primary endometrial stromal cells (HESCs) and human umbilical vein endothelial cells (HUVECs), and inhibited fibrosis of pretreated HESCs. In vivo, the DEFs significantly accelerated endometrial restoration, angiogenesis, and receptivity. Notably, the deposition of endometrial collagen decreased from 41.19 ± 2.16% to 14.15 ± 1.70% with DEFs treatment. Most importantly, in endometrium-injured rats, the use of DEFs increased the live birth rate from 30% to an impressive 90%, and the number and development of live births close to normal rats. The injectable "homing-like" bioactive DEFs system can achieve efficient live births and intrauterine injection of DEFs provides a new promising clinical strategy for endometrial factor infertility.

Fertility and anatomical outcomes following hysteroscopic adhesiolysis: An 11-year retrospective cohort study to validate a new classification system for intrauterine adhesions (Urman-Vitale Classification System)

OBJECTIVE

To propose a new classification system (Urman-Vitale Classification System) for intrauterine adhesions (IUAs) and to evaluate anatomical and fertility outcomes after hysteroscopic adhesiolysis accordingly.

METHODS

A retrospective analysis of consecutive patients treated over 11 years by a single operator in a tertiary care hospital. Women with sonographic suspicion of IUAs were scheduled for hysterosalpingography (HSG) and hysteroscopy for confirmation and treatment. IUAs were divided into five classes according to symptoms, ultrasound, HSG findings, and postsurgical hysteroscopic appearance. Hysteroscopic adhesiolysis was performed using a bipolar cutting electrode in an office setting. Evaluated outcomes were restoration of the uterine cavity, clinical pregnancy, pregnancy loss, and live birth rates.

RESULTS

A total of 227 patients (479 procedures) were included. Mean number of hysteroscopies increased in frequency with class of adhesions from Class 1 to Class 5 (1.0 ± 0.2 vs 2.3 ± 0.5; P = 0.001). Full restoration of the cavity was achieved in 100% of patients with Class 1 compared with 18.5% for Class 5 (43/43 vs 5/27; P = 0.001). Clinical pregnancy (Class 1 vs Class 4: P = 0.034; 1 vs 5: P = 0.006; 2 vs 5: P = 0.024) and live birth (Class 1 vs Class 4: P = 0.001; 1 vs 5: P = 0.006; 2 vs 4: P = 0.007; 2 vs 5: P = 0.0208) rates decreased with increasing severity of IUAs. Pregnancy loss rate was related to IUA severity (Class 1 vs Class 4: P = 0.012; 1 vs 5: P = 0.003: 2 vs 4: P = 0.014; 2 vs 5: P = 0.021).

CONCLUSION

A classification based on symptoms, imaging findings, and postsurgical macroscopic appearance of the uterine cavity could be useful in predicting prognosis and fertility in women with IUAs.

Mechanism of Smilax china L. in the treatment of intrauterine adhesions based on network pharmacology, molecular docking and experimental validation

BACKGROUND

Smilax china L. (SCL) is a traditional herbal medicine for the potential treatment of intrauterine adhesion (IUA). However, the mechanisms of action have not yet been determined. In this study, we explored the effects and mechanisms of SCL in IUA by network pharmacology, molecular docking and molecular biology experiments.

METHODS

Active ingredients and targets of SCL were acquired from TCMSP and SwissTargetPrediction. IUA-related targets were collected from the GeneCards, DisGeNET, OMIM and TTD databases. A protein‒protein interaction (PPI) network was constructed by Cytoscape 3.9.1 and analysed with CytoHubba and CytoNCA to identify the core targets. The DAVID tool was used for GO and KEGG enrichment analyses. Furthermore, molecular docking was employed to assess the interaction between the compounds and key targets. Finally, the mechanisms and targets of SCL in IUA were verified by cellular experiments and western blot.

RESULTS

A total of 196 targets of SCL were identified, among which 93 were related to IUA. Topological and KEGG analyses results identified 15 core targets that were involved in multiple pathways, such as inflammation, apoptosis, and PI3K/AKT signalling pathways. Molecular docking results showed that the active compounds had good binding to the core targets. In vitro experiments showed that astilbin (AST), a major component of SCL, significantly reduced TGF-β-induced overexpression of fibronectin (FN), activation of the PI3K/AKT signalling pathway and the expression of downstream factors (NF-κB and BCL2) in human endometrial stromal cells, suggesting that AST ameliorates IUA by mediating the PI3K/AKT/NF-κB and BCL2 proteins.

CONCLUSIONS

AST, a major component of SCL, may be a potential therapeutic agent for IUA. Moreover, its mechanism is strongly associated with regulation of the PI3K/AKT signalling pathway and the downstream NF-κB and BCL2 proteins. This study will provide new strategies that utilize AST for the treatment of IUA.

Human umbilical cord-derived mesenchymal stem cells and auto-crosslinked hyaluronic acid gel complex for treatment of intrauterine adhesion

OBJECTIVE

The purpose of this study was to explore the therapeutic characteristics of mesenchymal stem cells generated from human umbilical cord (hUC-MSCs) when utilized in conjunction with auto-crosslinked hyaluronic acid gel (HA-gel) for the management of intrauterine adhesion (IUA). The goal was to see how this novel therapy could enhance healing and improve outcomes for IUA patients.

METHODS

In this study, models of intrauterine adhesion (IUA) were established in Sprague-Dawley (SD) rats, which were then organized and divided into hUC-MSCs groups. The groups involved: hUC-MSCs/HA-gel group, control group, and HA-gel group. Following treatment, the researchers examined the uterine cavities and performed detailed analyses of the endometrial tissues to determine the effectiveness of the interventions.

RESULTS

The results indicated that in comparison with to the control group, both HA-gel, hUC-MSCs, and hUC-MSCs/HA-gel groups showed partial repair of IUA. However, in a more notable fashion transplantation of hUC-MSCs/HA-gel complex demonstrated significant dual repair effects. Significant outcomes were observed in the group treated with hUC-MSCs and HA-gel, they showed thicker endometrial layers, less fibrotic tissue, and a higher number of endometrial glands. This treatment strategy also resulted in a significant improvement in fertility restoration, indicating a profound therapeutic effect.

CONCLUSIONS

The findings of this study suggest that both HA-gel, hUC-MSCs, and hUC-MSCs/HA-gel complexes have the potential for partial repair of IUA and fertility restoration caused by endometrium mechanical injury. Nonetheless, the transplantation of the hUC-MSCs/HA-gel complex displayed exceptional dual healing effects, combining effective anti-adhesive properties with endometrial regeneration stimuli.

Minimally invasive delivery of human umbilical cord-derived mesenchymal stem cells by an injectable hydrogel via Diels-Alder click reaction for the treatment of intrauterine adhesions

Intrauterine adhesions (IUA) are the most common cause of uterine infertility, and conventional treatments have not consistently achieved satisfactory pregnancy rates. Stem cell therapy shows promising potential for the clinical treatment of IUA. Although various advanced biomaterials have been designed for delivering stem cells to the uterine cavity, there remain significant challenges, particularly in devising therapeutic strategies for clinical application that minimize surgical incisions and conform to the intricate structure of uterine cavity. Herein, an injectable hydrogel loaded with human umbilical cord-derived mesenchymal stem cells (UCMSCs) was synthesized via the Diels-Alder click reaction for endometrial regeneration and fertility restoration, exhibiting suitable mechanical properties, good biocompatibility, and desirable degradation properties. Notably, this hydrogel permitted minimally invasive administration and integrated seamlessly with surrounding tissue. Our study revealed that the UCMSCs-laden injectable hydrogel enhanced cell proliferation, migration, angiogenesis, and exhibited anti-fibrotic effects in vitro. The implantation of this hydrogel significantly facilitated endometrium regeneration and restored fertility in a rat endometrial damage model. Mechanistically, in vivo results indicated that the UCMSCs-laden injectable hydrogel effectively promoted macrophage recruitment and facilitated M2 phenotype polarization. Collectively, this hydrogel demonstrated efficacy in regenerating damaged endometrium, leading to the restoration of fertility. Consequently, it holds promise as a potential therapeutic strategy for endometrial damage and fertility decline arising from intrauterine adhesions. STATEMENT OF SIGNIFICANCE: Severe endometrial traumas frequently lead to intrauterine adhesions and subsequent infertility. Stem cell therapy shows promising potential for the clinical treatment of IUA; however, challenges remain, including low delivery efficiency and compromised stem cell activity during the delivery process. In this study, we fabricated an injectable hydrogel loaded with UCMSCs via the Diels-Alder click reaction, which exhibited unique bioorthogonality. The in situ-gelling hydrogels could be introduced through a minimally invasive procedure and adapt to the intricate anatomy of the uterus. The UCMSCs-laden injectable hydrogel promoted endometrial regeneration and fertility restoration in a rat endometrial damage model, efficaciously augmenting macrophage recruitment and promoting their polarization to the M2 phenotype. The administration of UCMSCs-laden injectable hydrogel presents a promising therapeutic strategy for patients with severe intrauterine adhesion.

Establishment and comparison of different procedures for modeling intrauterine adhesion in rats: A preliminary study

The establishment of a stable animal model for intrauterine adhesion (IUA) can significantly enhance research on the pathogenesis and pathological changes of this disease, as well as on the development of innovative therapeutic approaches. In this study, three different modeling methods, including phenol mucilage combined mechanical scraping, ethanol combined mechanical scraping and ethanol modeling alone were designed. The morphological characteristics of the models were evaluated. The underlying mechanisms and fertility capacity of the ethanol modeling group were analyzed and compared to those of the sham surgery group. All three methods resulted in severe intrauterine adhesions, with ethanol being identified as a reliable modeling agent and was subsequently subjected to further evaluation. Immunohistochemistry and RT-PCR results indicated that the ethanol modeling group exhibited an increase in the degree of fibrosis and inflammation, as well as a significant reduction in endometrial thickness, gland number, vascularization, and endometrial receptivity, ultimately resulting in the loss of fertility capacity. The aforementioned findings indicate that the intrauterine perfusion of 95 % ethanol is efficacious in inducing the development of intrauterine adhesions in rats. Given its cost-effectiveness, efficacy, and stability in IUA formation, the use of 95 % ethanol intrauterine perfusion may serve as a novel platform for evaluating innovative anti-adhesion materials and bioengineered therapies.

Review of Asherman syndrome and its hysteroscopic treatment outcomes: experience in a low-resource setting

BACKGROUND

Asherman syndrome is one of the endometrial factors that influence a woman's reproductive capacity. However, in our context, it needs to be well-documented. This study aimed to evaluate the clinical characteristics and hysteroscopic treatment outcomes of Asherman syndrome.

METHOD

A retrospective follow-up study from January 1, 2019, to December 31, 2022, was conducted on cases of Asherman syndrome after hysteroscopic adhesiolysis at St.Paul's Hospital in Addis Ababa, Ethiopia. Clinical data were collected via telephone survey and checklist. Epidata-4.2 and SPSS-26 were employed for data entry and analysis, respectively.

RESULT

A total of 177 study participants were included in the final analysis. The mean patient age was 31 years (range: 21-39) at the initial presentation, and 32.3 years (range: 22-40) during the phone interview. The majority of the patients (97.7%) had infertility, followed by menstrual abnormalities (73.5%). Among them, nearly half (47.5%) had severe, 38.4% had moderate, and 14.1% had mild Asherman syndrome. The review identified no factor for 51.4% of the participants. Endometrial tuberculosis affected 42 patients (23.7%). It was also the most frequent factor in both moderate and severe cases of Asherman syndrome. Only 14.7% of patients reported menstrual correction. Overall, 11% of women conceived. Nine patients miscarried, three delivered viable babies, and six were still pregnant. The overall rate of adhesion reformation was 36.2%. Four individuals had complications (3 uterine perforations and one fluid overload) making a complication rate of 2.3%.

CONCLUSION

Our study revealed that severe forms of Asherman syndrome, which are marked by amenorrhea and infertility, were more common, leading to incredibly low rates of conception and the resumption of regular menstruation, as well as high recurrence rates. A high index of suspicion for Asherman syndrome, quick and sensitive diagnostic testing, and the development of a special algorithm to identify endometrial tuberculosis are therefore essential. Future multi-centered studies should focus on adhesion preventive techniques.

Study on the Mechanism of Estrogen Regulating Endometrial Fibrosis After Mechanical Injury Via MIR-21-5P/PPARΑ/FAO Axis

BACKGROUND

Intrauterine adhesion (IUA) caused by endometrial mechanical injury has been found as a substantial risk factor for female infertility (e.g., induced abortion). Estrogen is a classic drug for the repair of endometrial injury, but its action mechanism in the clinical application of endometrial fibrosis is still unclear.

OBJECTIVE

To explore the specific action mechanism of estrogen treatment on IUA.

METHODS

The IUA model in vivo and the isolated endometrial stromal cells (ESCs) model in vitro were built. Then CCK8 assay, Real-Time PCR, Western Blot and Dual- Luciferase Reporter Gene assay were applied to determine the targeting action of estrogen on ESCs.

RESULTS

It was found that 17β-estradiol inhibited fibrosis of ESCs by down-regulating miR-21-5p level and activating PPARα signaling. Mechanistically, miR-21-5p significantly reduced the inhibitory effect of 17β-estradiol on fibrotic ESCs (ESCs-F) and its maker protein (e.g., α-SMA, collagen I, and fibronectin), where targeting to PPARα 3'- UTR and blocked its activation and transcription, thus lowering expressions of fatty acid oxidation (FAO) associated key enzyme, provoking fatty accumulation and reactive oxygen species (ROS) production, resulting in endometrial fibrosis. Nevertheless, the PPARα agonist caffeic acid counteracted the facilitation action of miR-21-5p on ESCs-F, which is consistent with the efficacy of estrogen intervention.

CONCLUSION

In brief, the above findings revealed that the miR-21-5p/PPARα signal axis played an important role in the fibrosis of endometrial mechanical injury and suggested that estrogen might be a promising agent for its progression.

Cyclical endometrial repair and regeneration: Molecular mechanisms, diseases, and therapeutic interventions

The endometrium is a unique human tissue with an extraordinary ability to undergo a hormone-regulated cycle encompassing shedding, bleeding, scarless repair, and regeneration throughout the female reproductive cycle. The cyclical repair and regeneration of the endometrium manifest as changes in endometrial epithelialization, glandular regeneration, and vascularization. The mechanisms encompass inflammation, coagulation, and fibrinolytic system balance. However, specific conditions such as endometriosis or TCRA treatment can disrupt the process of cyclical endometrial repair and regeneration. There is uncertainty about traditional clinical treatments' efficacy and side effects, and finding new therapeutic interventions is essential. Researchers have made substantial progress in the perspective of regenerative medicine toward maintaining cyclical endometrial repair and regeneration in recent years. Such progress encompasses the integration of biomaterials, tissue-engineered scaffolds, stem cell therapies, and 3D printing. This review analyzes the mechanisms, diseases, and interventions associated with cyclical endometrial repair and regeneration. The review discusses the advantages and disadvantages of the regenerative interventions currently employed in clinical practice. Additionally, it highlights the significant advantages of regenerative medicine in this domain. Finally, we review stem cells and biologics among the available interventions in regenerative medicine, providing insights into future therapeutic strategies.

Promotion of uterine reconstruction by a tissue-engineered uterus with biomimetic structure and extracellular matrix microenvironment

The recurrence rate for severe intrauterine adhesions is as high as 60%, and there is still lack of effective prevention and treatment. Inspired by the nature of uterus, we have developed a bilayer scaffold (ECM-SPS) with biomimetic heterogeneous features and extracellular matrix (ECM) microenvironment of the uterus. As proved by subtotal uterine reconstruction experiments, the mechanical and antiadhesion properties of the bilayer scaffold could meet the requirement for uterine repair. With the modification with tissue-specific cell-derived ECM, the ECM-SPS had the ECM microenvironment signatures of both the endometrium and myometrium and exhibited the property of inducing stem cell-directed differentiation. Furthermore, the ECM-SPS has recruited more endogenous stem cells to promote endometrial regeneration at the initial stage of repair, which was accompanied by more smooth muscle regeneration and a higher pregnancy rate. The reconstructed uterus could also sustain normal pregnancy and live birth. The ECM-SPS may thereby provide a potential treatment for women with severe intrauterine adhesions.

Efficacy of Mesenchymal Stem Cell-Derived Extracellular Vesicles in the Animal Model of Female Reproductive Diseases: A Meta-Analysis

BACKGROUND

Female reproductive disorders, such as premature ovarian insufficiency (POI), intrauterine adhesion (IUA) or thin endometrium, and polycystic ovary syndrome (PCOS), are the main factors affecting fertility. Mesenchymal stem cells derived-extracellular vesicles (MSC-EVs) have gained traction as a new potential treatment and were widely studied in these diseases. However, their impact is still not fully clear.

METHODS

A systematic search of PubMed, Web of Science, EMBASE, the Chinese National Knowledge of Infrastructure, and WanFang online databases was performed up to September 27th, 2022, and the studies of MSC-EVs-based therapy on the animal models of female reproductive diseases were included. The primary outcomes were anti-Müllerian hormone (AMH) in POI and endometrial thickness in IUA, respectively.

RESULTS

28 studies (POI, N = 15; IUA, N = 13) were included. For POI, MSC-EVs improved AMH at 2 weeks (SMD 3.40, 95% CI 2.02 to 4.77) and 4 weeks (SMD 5.39, 95% CI 3.43 to 7.36) compared with placebo, and no difference was found when compared with MSCs in AMH (SMD -2.03, 95% CI -4.25 to 0.18). For IUA, MSC-EVs treatment could increase the endometrial thickness at 2 weeks (WMD 132.36, 95% CI 118.99 to 145.74), but no improvement was found at 4 weeks (WMD 166.18, 95% CI -21.44 to 353.79). The combination of MSC-EVs with hyaluronic acid or collagen had a better effect on the endometrial thickness (WMD 105.31, 95% CI 85.49 to 125.13) and glands (WMD 8.74, 95% CI 1.34 to 16.15) than MSC-EVs alone. The medium dose of EVs may allow for great benefits in both POI and IUA.

CONCLUSIONS

MSC-EVs treatment could improve the functional and structural outcomes in female reproductive disorders. The combination of MSC-EVs with HA or collagen may enhance the effect. These findings can accelerate the translation of MSC-EVs treatment to human clinical trials.

The use of intrauterine balloon therapy in reproductive medicine and surgery: a guidance for practice

The use of balloon therapy in obstetric practice especially in postpartum haemorrhage (PPH) is well established and has recently been reviewed. However, little attention has been drawn regarding the use of intrauterine balloon (IUB) in gynaecological practice. This study focuses on the various usage of IUB in gynaecological practice. An electronic literature search through Medline, EMBASE and Clinicaltrial.gov from inception to August 2022 was conducted. The study focuses on the three following areas: (1) Indications: prevention and removal of intrauterine adhesions, management of ectopic pregnancy, facilitation of endoscopic surgery and other clinical usages; (2) Practical aspects of balloon therapy including ultrasound guidance, choice of balloon, inflation volume, duration of balloon therapy; and (3) Potential complications including pain, infection, uterine rupture and how they can be avoided. IUB therapy is a simple, inexpensive and effective method that can be applied in various gynaecological conditions ranging from IUA to intrauterine haemorrhage. Complications are rare, but in most cases can be avoided with correct use.

Etiology, Risk Factors, and Management of Asherman Syndrome

Asherman syndrome is characterized by a triad of symptoms including pain, menstrual abnormalities, and infertility and is a result of intrauterine scar tissue after instrumentation of a gravid uterus. Saline sonohysterogram is typically the most sensitive diagnostic tool; however, hysteroscopy is the criterion standard for diagnosis. Treatment includes hysteroscopic-guided lysis of adhesion, with restoration of the anatomy of the uterine cavity. Several modalities are used in an attempt to reduce the reformation of scar tissue after surgery; however, there is no consensus on the ideal method. Stem cells and platelet-rich plasma are being explored as means of regenerative therapy for the endometrium, but data remain limited. At present, most individuals can have restoration of menstrual function; however, lower pregnancy rates and obstetric complications are not uncommon. These complications are worse for patients with a higher grade of disease. Efforts are needed in standardizing classification, reducing uterine instrumentation of the gravid uterus, and referring patients to health care professionals with clinical expertise in this area.

Treatment strategies for intrauterine adhesion: focus on the exosomes and hydrogels

Intrauterine adhesion (IUA), also referred to as Asherman Syndrome (AS), results from uterine trauma in both pregnant and nonpregnant women. The IUA damages the endometrial bottom layer, causing partial or complete occlusion of the uterine cavity. This leads to irregular menstruation, infertility, or repeated abortions. Transcervical adhesion electroreception (TCRA) is frequently used to treat IUA, which greatly lowers the prevalence of adhesions and increases pregnancy rates. Although surgery aims to disentangle the adhesive tissue, it can exacerbate the development of IUA when the degree of adhesion is severer. Therefore, it is critical to develop innovative therapeutic approaches for the prevention of IUA. Endometrial fibrosis is the essence of IUA, and studies have found that the use of different types of mesenchymal stem cells (MSCs) can reduce the risk of endometrial fibrosis and increase the possibility of pregnancy. Recent research has suggested that exosomes derived from MSCs can overcome the limitations of MSCs, such as immunogenicity and tumorigenicity risks, thereby providing new directions for IUA treatment. Moreover, the hydrogel drug delivery system can significantly ameliorate the recurrence rate of adhesions and the intrauterine pregnancy rate of patients, and its potential mechanism in the treatment of IUA has also been studied. It has been shown that the combination of two or more therapeutic schemes has broader application prospects; therefore, this article reviews the pathophysiology of IUA and current treatment strategies, focusing on exosomes combined with hydrogels in the treatment of IUA. Although the use of exosomes and hydrogels has certain challenges in treating IUA, they still provide new promising directions in this field.

Prevention strategies of postoperative adhesion in soft tissues by applying biomaterials: Based on the mechanisms of occurrence and development of adhesions

Postoperative adhesion (POA) widely occurs in soft tissues and usually leads to chronic pain, dysfunction of adjacent organs and some acute complications, seriously reducing patients' quality of life and even being life-threatening. Except for adhesiolysis, there are few effective methods to release existing adhesion. However, it requires a second operation and inpatient care and usually triggers recurrent adhesion in a great incidence. Hence, preventing POA formation has been regarded as the most effective clinical strategy. Biomaterials have attracted great attention in preventing POA because they can act as both barriers and drug carriers. Nevertheless, even though much reported research has been demonstrated their efficacy on POA inhibition to a certain extent, thoroughly preventing POA formation is still challenging. Meanwhile, most biomaterials for POA prevention were designed based on limited experiences, not a solid theoretical basis, showing blindness. Hence, we aimed to provide guidance for designing anti-adhesion materials applied in different soft tissues based on the mechanisms of POA occurrence and development. We first classified the postoperative adhesions into four categories according to the different components of diverse adhesion tissues, and named them as "membranous adhesion", "vascular adhesion", "adhesive adhesion" and "scarred adhesion", respectively. Then, the process of the occurrence and development of POA were analyzed, and the main influencing factors in different stages were clarified. Further, we proposed seven strategies for POA prevention by using biomaterials according to these influencing factors. Meanwhile, the relevant practices were summarized according to the corresponding strategies and the future perspectives were analyzed.

Construction and evaluation of intrauterine adhesion model in rats by different methods of mechanical injury

PURPOSE

The study aimed to establish a stable and effective animal model for the experimental study of intrauterine adhesion (IUA) by evaluating various mechanical injury methods.

METHODS

A total of 140 female rats were divided into four groups according to the extent and area of endometrial injury: group A (excision area: 2.0 × 0.5 cm²), group B (excision area: 2.0 × 0.25 cm²), group C (endometrial curettage) and group D (sham operation). On the 3rd, 7th, 15th and 30th day after the operation, the tissue samples of each group were collected, and the uterine cavity stenosis and histological changes were recorded by HE and Masson staining. Immunohistochemistry of CD31 was applied to visualize microvessel density (MVD). The pregnancy rate and the number of gestational sacs were used to evaluate the reproductive outcome.

RESULTS

The results showed that endometrium injured by small-area endometrial excision or simple curettage could be repaired. The ratio of fibrosis in groups A and B was higher than that in groups C and group D 30 days after modeling (P < 0.001). The number of endometrial glands and MVD in group A was significantly lower than those in groups B, C and D (P < 0.05). The pregnancy rate in group A was 20%, which was lower than that in groups B (33.3%), C (89%) and D (100%) (P < 0.05).

CONCLUSION

Full-thickness endometrial excision has a high rate of success in constructing stable and effective IUA models in rats.

PDGFBB improved the biological function of menstrual blood-derived stromal cells and the anti-fibrotic properties of exosomes

BACKGROUND

Intrauterine adhesion (IUA) is a reproductive dysfunction disease characterized by endometrial fibrosis, with limited therapeutic options and poor prognosis. Our previous studies confirmed that menstrual blood-derived stromal cells (MenSCs) effectively attenuated endometrial fibrosis in an animal model of IUA mainly through exosomes. This therapeutic effect can be enhanced by platelet-rich plasma (PRP), in which PDGFBB is an abundant growth factor. Therefore, we aimed to compare the effects of PRP and PDGFBB on the biological activities of MenSCs in vitro, and to further investigate the molecular mechanism of MenSCs-derived exosomes in alleviating endometrial fibrosis.

METHODS

MenSCs were isolated for in vitro functional assays to examine the viability, migration, and stemness of MenSCs. Endometrial stromal cells (EndoSCs) were treated with 50 ug/ml of MenSCs-derived exosomes, obtained by differential ultracentrifugation extraction. The molecular mechanisms by which PDGFBB improves MenSCs and exosomes alleviate EndoSCs fibrosis were then explored using immunofluorescence, western blot, and co-immunoprecipitation.

RESULTS

Both 100 ng/ml PDGFBB and 10% activated PRP promoted the proliferation, increased the S phase of cell cycle, and inhibited apoptosis of MenSCs in vitro. Compared with PRP, PDGFBB significantly promoted MenSCs migration. All of these effects were inhibited by sorafenib, a PDGFR-β inhibitor. PRP and PDGFBB activated AKT/NF-κB signaling pathway in MenSCs and increased the expression of P65 and OCT4. Moreover, pretreatment of PDGFBB did not increase the secretion of MenSCs but significantly increased the anti-fibrosis effects of MenSCs-derived exosomes on IUA-EndoSCs. MenSCs-derived exosomes attenuated SMAD3 phosphorylation and increased YAP ubiquitination, which reduced the binding of YAP/SMAD3. Pretreatment with PDGFBB amplified this effect.

CONCLUSIONS

In summary, PDGFBB could improve the biological functions of MenSCs via AKT/NF-κB signaling pathway, including viability, migration, and stemness. Our results indicated that PDGFBB amplified MenSCs-derived exosomes to attenuate endometrial fibrosis by inhibiting YAP activity, revealing a novel mechanism by which PRP enhanced the ability of MenSCs to repair tissue injury and providing a potential option for improving stem cell efficacy in IUA.

Label-free proteomic analysis and functional analysis in patients with intrauterine adhesion

Intrauterine adhesion (IUA) is one of the principal causes of secondary infertility in women of reproductive age, which seriously affects female reproductive function and quality of life. In recent years, the incidence of IUA has been increasing year by year, but its pathological mechanism has not yet been clarified. This study intended to reveal the pathogenesis of IUA and find new therapeutic targets by analyzing the proteomic differences between intrauterine adhesion tissues and normal human endometrial tissues. In the label-free quantitative proteomics, we identified 789 up-regulated differentially expressed proteins (DEPs) and 539 down-regulated DEPs. These DEPs were further analyzed by Gene Ontology (GO) annotation and enrichment analysis, Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis to preliminarily clarify the biomarkers involved in the pathogenesis of the IUA. The DEPs were further verified by parallel reaction monitoring (PRM) to confirm the results of proteomics. Finally, 7 target proteins may be candidates for treatment and elucidating the pathophysiology of IUA. SIGNIFICANCE: IUA is a fertility complication, which has increasing incidence recently. Until now, only a little research paid attention to the proteomic changes of IUA. This is the first study focused on the comparative analysis of endometrial tissue between IUA patients and normal women. We found 7 key proteins that may become the potential biomarkers of IUA.

Bioactive Injectable and Self-Healing Hydrogel Via Cell-Free Fat Extract for Endometrial Regeneration

The damaged endometrium and the formation of fibrosis are key barriers to pregnancy and further lead to infertility. However, how to promote endometrium repair is always a challenge. Here, a bioactive injectable and self-healing hydrogel is developed by physically combination of thiolated polyethylene (PEG), Cu²⁺ and cell-free fat extract (CEFFE, CF) for endometrial regeneration and fertility. By inheriting the advantages of various active proteins contained in CEFFE, it could induce the overall repair of endometrial microenvironment for intrauterine adhesion (IUA). In vitro, CF@Cu-PEG reduces endometrial cell apoptosis by more than 50%, and increases angiogenesis by 92.8%. In the IUA mouse, injection of CF@Cu-PEG significantly reduces the rate of uterine hydrometra and prevents the formation of endometrial fibrosis. Remarkably, CF@Cu-PEG contributes to the repair of endometrial microstructure, especially increases the number of endometrial pinopodes, significantly improves endometrial receptivity, and increases the pregnancy rate of IUA mice from 7.14% to 66.67%. In summary, through the physically combination of CEFFE and Cu-PEG, the construction of loaded bioactive injectable hydrogel not only inhibits the IUA, but also induces the self-repair of endometrial cells in situ and improves fertility, providing a new strategy for IUA repair in clinical application.

Homogenous subpopulation of human mesenchymal stem cells and their extracellular vesicles restore function of endometrium in an experimental rat model of Asherman syndrome

BACKGROUND

Asherman syndrome (AS), or intrauterine adhesions, is a main cause of infertility in reproductive age women after endometrial injury. Mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) are promising candidates for therapies that repair damaged endometria. However, concerns about their efficacy are attributed to heterogeneity of the cell populations and EVs. A homogenous population of MSCs and effective EV subpopulation are needed to develop potentially promising therapeutic options in regenerative medicine.

METHODS

AS model was induced by mechanical injury in adult rat uteri. Then, the animals were treated immediately with homogeneous population of human bone marrow-derived clonal MSCs (cMSCs), heterogenous parental MSCs (hMSCs), or cMSCs-derived EV subpopulations (EV20K and EV110K). The animals were sacrificed two weeks post-treatment and uterine horns were collected. The sections were taken, and hematoxylin-eosin was used to examine the repair of endometrial structure. Fibrosis was measured by Masson's trichrome staining and α-SMA and cell proliferation by Ki67 immunostaining. The function of the uteri was explored by the result of mating trial test. Expression changes of TNFα, IL-10, VEGF, and LIF were assayed by ELISA.

RESULTS

Histological analysis indicated fewer glands, thinner endometria, increased fibrotic areas, and decreased proliferation of epithelial and stroma of the uteri in the treated compared with intact and sham-operated animals. However, these parameters improved after transplantation of both types of cMSCs and hMSCs and/or both cryopreserved EVs subpopulations. The cMSCs demonstrated more successful implantation of the embryos in comparison with hMSCs. The tracing of the transplanted cMSCs and EVs showed that they migrated and localized in the uteri. Protein expression analysis results demonstrated downregulation of proinflammatory factor TNFα and upregulation of anti-inflammatory cytokine IL-10, and endometrial receptivity cytokines VEGF and LIF in cMSC- and EV20K-treated animals.

CONCLUSION

Transplantation of MSCs and EVs contributed to endometrial repair and restoration of reproductive function, likely by inhibition of excessive fibrosis and inflammation, enhancement of endometrial cell proliferation, and regulation of molecular markers related to endometrial receptivity. Compared to classical hMSCs, cMSCs were more efficient than hMSCs in restoration of reproductive function. Moreover, EV20K is more cost-effective and feasible for prevention of AS in comparison with conventional EVs (EV110K).

Improvement of vaginal probiotics Lactobacillus crispatus on intrauterine adhesion in mice model and in clinical practice

BACKGROUND

Intrauterine adhesion (IUA) is a frequent acquired endometrial condition, for which there is no effective preventive or treatment. Previous studies have found that vaginal microbiota dysregulation is closely related to endometrial fibrosis and IUA. Therefore, we wondered whether restoration of vaginal microbiota by vaginal administration of L. crispatus could prevent endometrial fibrosis and ameliorate IUA.

RESULTS

First, we created a mechanically injured mouse model of IUA and restored the mice's vaginal microbiota by the addition of L. crispatus convolvulus. The observations suggested that intrauterine injections of L. crispatus significantly decreased the degree of uterine fibrosis, the levels of IL-1β and TNF-α in blood, and downregulated the TGF-β1/SMADs signaling pathway in IUA mice. A therapy with L. crispatus considerably raised the abundance of the helpful bacteria Lactobacillus and Oscillospira and restored the balance of the vaginal microbiota in IUA mice, according to high-throughput sequencing. Then we conducted a randomized controlled trial to compare the therapeutic effect of L. crispatus with estrogen after transcervical resection of adhesion (TCRA). And the results showed that vaginal probiotics had a better potential to prevent intrauterine adhesion than estrogen.

CONCLUSIONS

This study confirmed that L. crispatus could restore vaginal microbiota after intrauterine surgery, inhibit endometrial fibrosis, and finally play a preventive and therapeutic role in IUA. At the same time, it is a new exploration for the treatment of gynecological diseases with vaginal probiotics.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/ , identifier (ChiCTR1900022522), registration time: 15/04/2019.

Incidence and Clinical Implications of Placenta Accreta Spectrum after Treatment for Asherman Syndrome

STUDY OBJECTIVE

To investigate the incidence, predictors, and clinical implications of placenta accreta spectrum (PAS) in pregnancies after hysteroscopic treatment for Asherman syndrome (AS).

DESIGN

This is a retrospective cohort study, conducted through a telephone survey and chart review.

SETTING

Minimally invasive gynecologic surgery center in an academic community hospital.

PATIENTS

Database of 355 patients hysteroscopically treated for AS over 4 years. We identified patients who achieved pregnancy past the first trimester and evaluated the incidence and predictors for PAS as well as associated clinical implications.

INTERVENTIONS

Telephone survey.

MEASUREMENTS AND MAIN RESULTS

We identified 97 patients meeting the inclusion criteria. Among these patients, 23 (23.7%) patients had PAS. History of cesarean delivery was the only variable statistically significantly associated with having PAS (adjusted odds ratio 4.03, 95% confidence interval 1.31-12.39). PAS was diagnosed antenatally in 3 patients (14.3%), with patients having placenta previa more likely to be diagnosed (p <.01). Nine patients (39.13%) with PAS required cesarean hysterectomy, which is 9.3% of those with a pregnancy that progressed past the first trimester. Factors associated with cesarean hysterectomy were the etiology of AS (dilation and evacuation after the second trimester pregnancy or postpartum instrumentation, p <.01), invasive placenta (increta or percreta, p <.05), and history of morbidly adherent placenta in previous pregnancies (p <.05). Two patients with PAS (9.5%) had uterine rupture, and another 2 (9.5%) experienced uterine inversion.

CONCLUSION

There is a high incidence of PAS and associated morbidity in pregnancies after hysteroscopic treatment for AS. There is a low rate of antenatal diagnosis as well as a lack of reliable clinical predictors, which both stress the importance of clinical awareness, careful counseling, and delivery planning.

Umbilical cord mesenchymal stem cell-derived exosomes reverse endometrial fibrosis by the miR-145-5p/ZEB2 axis in intrauterine adhesions

RESEARCH QUESTION

What is the specific mechanism of umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-exos) in regulating endometrial repair and regeneration?

DESIGN

In this study, UCMSC-exos were harvested by differential ultracentrifugation from umbilical cord mesenchymal stem cell culture supernatant and identified with western blotting, transmission electron microscopy and nanoparticle tracking analysis. Transforming growth factor-β1 (TGFβ1) at different concentrations was used to construct the intrauterine adhesions cell model. The fibrotic markers were assessed by quantitative reverse transcription-polymerase chain reaction and western blotting. The effects of miR-145-5p over-expression on endometrial fibrosis were assessed. Dual luciferase assay was performed to verify the relationship between miR-145-5p and zinc finger E-box binding homeobox 2 (ZEB2).

RESULTS

The isolated UCMSC-exos had a typical cup-shaped morphology, expressed the specific exosomal markers Alix, CD63 and TSG101, and were approximately 50-150 nm in diameter. TGFβ1 at 10 ng/ml significantly promoted endometrial fibrosis, which was reversed by 20 µg/ml UCMSC-exos. Exosomal miR-145-5p ameliorated TGFβ1-induced endometrial fibrosis. ZEB2 was inversely regulated by exosomal miR-145-5p as a direct target.

CONCLUSIONS

UCMSC-exos might reverse endometrial stromal cell fibrosis by regulating the miR-145-5p/ZEB2 axis, representing a potential novel strategy to promote endometrial repair.

The effect of the combined use of an intrauterine device and a Foley balloon in the prevention of adhesion following hysteroscopic adhesiolysis

The aim of this study was to determine whether intrauterine device (IUD) combined with Foley balloon could obtain better efficacy in preventing re-adhesion for patients with intrauterine adhesions (IUAs). The data of 89 patients with IUAs, who underwent transcervical resection of adhesion (TCRA) operation, were retrospectively collected. According to the method used for preventing re-adhesion of the uterine cavity after TCRA, the enrolled patients were divided into IUD group, Foley balloon group and the combined group. The second-look hysteroscopy was carried out at 3 months after TCRA surgery. The severity and extent of IUA were scored by American Fertility Society (AFS) scoring system. The endometrial thickness (EMT) was measured by ultrasound. Furthermore, the menstruation and pregnancy outcomes were also assessed. Our results showed that the postoperative decrease in AFS score was significantly greater in the combined group than in the IUD group or in the Foley balloon group. The increase in menstrual score among the 3 groups was not significantly different. The difference between preoperative and postoperative values of EMT was greater in the combined group than in the other 2 groups. In conclusion, the effect of a Foley balloon combined with IUD in preventing re-adhesion after TCRA might be better than that of IUD or Foley balloon alone.

Telocyte-Derived Exosomes Provide an Important Source of Wnts That Inhibits Fibrosis and Supports Regeneration and Repair of Endometrium

Intrauterine adhesions (IUAs) often occurred after common obstetrical and gynecological procedures or infections in women of reproductive age. It was characterized by the formation of endometrial fibrosis and prevention of endometrial regeneration, usually with devastating fertility consequences and poor treatment outcomes so far. Telocytes (TCs), as a novel interstitial cell type, present in female uterus with in vitro therapeutic potential in decidualization-defective gynecologic diseases. This study aims to further investigate the role of TC-derived Wnt ligands carried by exosomes (Exo) in reversal of fibrosis and enhancement of regeneration repair in endometrium. IUA cellular and animal models were established from endometrial stromal cells (ESCs) and mice, followed with treatment of TC-conditioned medium (TCM) or TC-derived Exo. In cellular model, fibrosis markers (collagen type 1 alpha 1 [COL1A1], fibronectin [FN], and α-smooth muscle actin [α-SMA]), angiogenesis (vascular endothelial growth factor [VEGF]), and pathway protein (β-catenin) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting (WB), and immunofluorescence. Results showed that, TCs (either TCM or TC-derived Exo) provide a source of Wnts that inhibit cellular fibrosis, as evidenced by significantly elevated VEGF and β-catenin with decreased fibrotic markers, whereas TCs lost salvage on fibrosis after being blocked with Wnt/β-catenin inhibitors (XAV939 or ETC-159). Further in mouse model, regeneration repair (endometrial thickness, number of glands, and fibrosis area ratio), fibrosis markers (fibronectin [FN]), mesenchymal-epithelial transition (MET) (E-cadherin, N-cadherin), and angiogenesis (VEGF, microvessel density [MVD]) were studied by hematoxylin-eosin (HE), Masson staining, and immunohistochemistry. Results demonstrated that TC-Exo treatment effectively promotes regeneration repair of endometrium by relieving fibrosis, enhancing MET, and angiogenesis. These results confirmed new evidence for therapeutic perspective of TC-derived Exo in IUAs.