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

A short peptide encoded by long non-coding RNA small nucleolar RNA host gene 6 promotes cell migration and epithelial-mesenchymal transition by activating transforming growth factor-beta/SMAD signaling pathway in human endometrial cells

BACKGROUND

Endometrial dysfunction is closely correlated with the development of multiple severe gynecological disorders including intrauterine adhesion. Accumulating evidence supports that some long non-coding RNAs (lncRNAs) have peptide-coding potential. In this text, the peptide-coding ability of lncRNA SNHG6 was examined. Also, the effects of an SNHG6-encoded peptide on the viability and migration of human endometrial stromal cells (hESCs) and human endometrial epithelial cells (hEECs) and related molecular mechanisms were explored.

METHODS

The peptide-encoding potential of SNHG6 was predicted by FuncPEP and getorf databases and validated by western blot assay. Cell viability was tested by cell counting kit-8 assay. Cell migratory ability was examined by wound healing and transwell migration assays. Protein levels of genes were measured by western blot assay.

RESULTS

Prediction analysis suggested that SNHG6 had the potential peptide-coding ability and multiple open-reading frames (ORFs). Western blot validated that SNHG6 ORF#1 and ORF#2 could translate into short peptides. SNHG6 ORF#2 overexpression facilitated cell migration and epithelial-mesenchymal transition (EMT) in hESCs and hEECs, while these effects were abrogated by transforming growth factor-beta (TGF-β)/SMAD signaling inhibitor GW788388. Moreover, GW788388 inhibited the increase of p-SMAD2 and p-SMAD3 levels induced by SNHG6 ORF#2 in hESCs. SNHG6 ORF#2-encoded peptide did not influence endometrial stromal and epithelial cell viability.

CONCLUSIONS

LncRNA SNHG6 ORF#1 and ORF#2 could translate into small peptides and SNHG6 ORF#2 overexpression promoted cell migration and EMT by activating the TGF-β/SMAD pathway in hESCs and hEECs, suggesting the potential roles of SNHG6-encoded peptides in the development of endometrial stromal and epithelial cells and related gynecological diseases.

Cell therapy for the treatment of reproductive diseases and infertility: an overview from the mechanism to the clinic alongside diagnostic methods

Infertility is experienced by 8%-12% of adults in their reproductive period globally and has become a prevalent concern. Besides routine therapeutic methods, stem cells are rapidly being examined as viable alternative therapies in regenerative medicine and translational investigation. Remarkable progress has been made in understanding the biology and purpose of stem cells. The affected pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs) are further studied for their possible use in reproductive medicine, particularly for infertility induced by premature ovarian insufficiency and azoospermia. Accordingly, this study discusses current developments in the use of some kinds of MSCs such as adipose-derived stem cells, bone marrow stromal cells, umbilical cord MSCs, and menstrual blood MSCs. These methods have been used to manage ovarian and uterine disorders, and each technique presents a novel method for the therapy of infertility.

The link between intrauterine adhesions and impaired reproductive performance: a systematic review of the literature

Background

Intrauterine adhesions (IUAs) are one of the main reproductive system diseases in women worldwide. Fusion between the injured opposing walls leads to partial-to-complete obliteration of the cavity and/or cervical canal. The main clinical manifestations in case of IUAs are menstrual disturbances, cyclic pain and reproductive disorders. The reproductive outcomes of women with IUAs remain limited and inefficient compared to women without IUAs, even after adhesiolysis. An exact understanding of the underlying mechanisms and processes to explain the compromised reproductive performance and outcomes in case of IUAs are lacking.

Methods

A systematic literature review of MEDLINE-PubMed (1966 to January 2022) and EMBASE (1974 to January 2022) was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were included if they reported underlying causes, related mechanisms and processes to explain the association between IUAs and impaired reproductive performance, pregnancy and obstetric complications.

Results

After an extensive review of the literature, 58 articles were identified reporting underlying mechanisms to explain the association between IUAs and impaired fertility. Intrauterine scarring influences the process of fertilization, reproductive performance and ultimately reproductive outcome. IUAs can disturb the cervico-utero-tubal sperm transport and result in an avascular and unresponsive endometrium with decreased receptivity and thickness. Abnormal decidualization and abnormal trophoblastic infiltration leads to placental attachment disorders. Moreover, the risk for premature delivery, intrauterine fetal growth restriction and fetal anomalies is increased in case of IUAs.

Conclusion

The impact of IUAs on reproductive performance, even after adhesiolysis, is becoming more apparent. The postulated mechanisms to explain the association are related to sperm transport, embryo implantation and placentation. Prevention, by preserving the basal layer of the endometrium is essential. Effective and evidence-based strategies for the prevention of endometrial injury and formation of IUAs, are urgently needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05164-2.

Reproductive Outcomes and Overall Prognosis of Women with Asherman's Syndrome Undergoing IVF

STUDY OBJECTIVE

To evaluate the impact of Asherman syndrome (AS) following hysteroscopic adhesiolysis on reproductive outcomes and the time to achieve pregnancy in women with infertility undergoing in vitro fertilization (IVF) treatment.

DESIGN

Case-control study.

SETTING

Tertiary university-affiliated medical center.

PATIENTS

Fifty-one infertile women who were treated for AS and underwent IVF (study group) matched for age and etiology of infertility with non-AS controls at a 1:1 ratio.

INTERVENTIONS

Medical records search, chart review, and phone survey were used to assess reproductive outcomes.

MEASUREMENTS AND MAIN RESULTS

A multivariate logistic regression analyses was used to assess live birth, accounting for patient age at stimulation cycle start, parity, number of embryos transferred, and endometrial thickness. A survival analysis was performed to assess the times that had lapsed from interventions to conception. The study group of 51 women included 38 (74.5%) with moderate to severe disease. The mean number of embryo transfers per woman was similar for the study and control groups (4.9 ± 4.6 vs 6.22 ± 4.3, respectively, p = .78). The controls had a significantly higher mean endometrial thickness before embryo transfer (8.7 ± 1.8 mm vs 6.95 ± 1.7 mm, p = .001). The overall time to achieve live birth was significantly longer in women with AS (p = .022). In a logistic regression analysis, the presence of moderate to severe AS was shown to be an independent factor for achieving a live birth (adjusted odds ratio 0.174, 95% confidence interval [CI], 0.032-0.955, p = .004). Women with AS who had live births had a significantly thicker mean endometrial thickness (8.2 ± 1.4 mm vs 6.9 ± 1.2, p = .001).

CONCLUSION

Moderate and severe AS has a detrimental effect on reproductive performance in infertile women. Endometrial thickness is an important predictor for live births among women with AS who undergo IVF.

Extracellular vesicles in reproduction and pregnancy

Extracellular vesicles (EVs) are small, lipid-bound packages that are secreted by all cell types and have been implicated in many diseases, such as cancer and neurodegenerative disorders. Though limited, an exciting new area of EV research focuses on their role in the reproductive system and pregnancy. In males, EVs have been implicated in sperm production and maturation. In females, EVs play a vital role in maintaining reproductive organ homeostasis and pregnancy, including the regulation of folliculogenesis, ovulation, and embryo implantation. During the development and maintenance of a pregnancy, the placenta is the main form of communication between the mother and the developing fetus. To support the developing fetus, the placenta will act as numerous vital organs until birth, and release EVs into the maternal and fetal bloodstream. EVs play an important role in cell-to-cell communication and may mediate the pathophysiology of pregnancy-related disorders such as preeclampsia, gestational diabetes mellitus, preterm birth, and intrauterine growth restriction, and potentially serve as noninvasive biomarkers for these conditions. In addition, EVs may also mediate processes involved in both male and female infertility. Together, the EVs secreted by both the male and female reproductive tracts work to promote reproductive fertility and play vital roles in mediating maternal-fetal crosstalk and pregnancy maintenance.

Comparison of the localization of intrauterine adhesions in pregnant and infertile women

Objective:

Intrauterine adhesion (IUA) is the formation of band-shaped fibrotic tissues in the endometrial cavity due to uterine procedures. Most adhesions remain asymptomatic and do not affect fertility or pregnancy conditions. However, they may lead to infertility and pregnancy complications in some women. This study aimed to determine which localization and type of IUA may lead to infertility.

Materials and Methods:

Seventy-six women with IUA were retrospectively scanned. Thirty-nine women with IUA with uterine factor-related infertility were included in the infertility group. Thirty-seven pregnant women, who had adhesions in the second-trimester ultrasonography and who had a live birth via cesarean section at term, were included in the pregnancy group. The localization of adhesions was determined as the fundus, corpus, isthmus, and cornu. Concerning the type of adhesion, the adhesions were classified as dense- and film-type adhesions.

Results:

The infertility group was compared with the pregnancy group according to the type and localization of the adhesions. Fundal adhesions were significantly higher in the infertility group compared to the pregnancy group (p<0.05). The isthmic adhesions, however, were more common in the pregnancy group than in the infertility group (p<0.05). Dense-type adhesions were more common in the infertility group than in the pregnancy group (p<0.05).

Conclusion:

According to the localization and types of adhesions, fundal and dense-type adhesions are among the features of uterine factor-related infertility. However, isthmus-located and film-type adhesions may not cause infertility.

Animal models in intrauterine adhesion research

Intrauterine adhesion (IUA) is a gynaecological disease caused by uterine cavity surgeries and infections that leads to partial or total occlusion of the uterine cavity. However, the underlying mechanism(s) and progression of the disease have not yet been identified. IUA has a high recurrence rate and poor prognosis, and effective drugs to prevent adhesion are lacking. Therefore, establishing an effective animal model of IUA is of great significance for revealing the pathogenesis of IUA and the mechanism(s) governing drug effects. Rats, mice, rabbits, and other animals are currently used to establish intrauterine adhesion models. The IUA induction methods include chemical, thermal, or mechanical damage and mechanical damage combined with an infective method. We analysed the advantages and disadvantages of various models and their clinical simulations in order to provide a precise animal model for exploring the pathogenesis, treatment strategies, and prevention of IUA.

Melatonin-primed MSCs alleviate intrauterine adhesions by affecting MSC-expressed galectin-3 on macrophage polarization

Intrauterine adhesion (IUA) is characterized by the presence of fibrosis on the uterine cavity. It is mainly caused by infection or trauma to the endometrium, and it imposes a great challenge to female reproductive health. Mesenchymal stem cells (MSCs) have been used to regenerate the human endometrium in patients with IUA, but stem cell therapy is not curative in some patients. Melatonin (MT) was reported as a potential modulator of MSCs. However, it remains unclear whether MSCs pretreated with MT exert an improved therapeutic effect on IUA. In this study, an IUA model was established using our invented electric scratching tool. Our results illustrated that MT-pretreated MSCs significantly attenuated the development of IUA. Moreover, MT-pretreated MSCs highly expressed galectin-3 (Gal-3), which enhanced MSC proliferation and migration and influenced macrophage polarization. Of note, IUA mice exhibited colonic injury, and MT-pretreated MSCs alleviated this injury by normalizing colonic microbial communities and recruiting macrophages. Furthermore, inhibition of sympathetic nerves had no effect on IUA progression but delayed colonic injury, and Gal-3 combined with norepinephrine better promoted M2-like macrophage polarization and inhibited M1-like macrophage polarization. Together, these data indicated that MT-primed MSCs can ameliorate injury of both the uterus and colon in an IUA model through high Gal-3 expression to influence sympathetic nerves and in turn affect the polarization and recruitment of macrophages.

Clinical Evaluation of Autologous and Allogeneic Stem Cell Therapy for Intrauterine Adhesions: A Systematic Review and Meta-Analysis

Objective

Intrauterine adhesions (IUAs) are a major cause of female infertility. Stem cells can be used to restore endometrial function owing to their regenerative abilities. We compared the safety and efficacy of autologous and allogeneic stem cell treatments in patients with recurrent IUA after conventional therapy based on a systematic review of the related literature.

Methods

The PubMed, Embase, and Cochrane databases were systematically searched. All analysis were performed using Review Manager 5.4. We compared improvements in endometrial thickness, pregnancy rates, menstruation, and side effects after autologous and allogeneic stem cell therapy. The study was registered with PROSPERO, CRD 42022322870.

Results

Our search returned 154 reports, 10 of which met the inclusion criteria, representing 116 patients. Of these, 44 patients in two studies were treated with allogeneic stem cells and 72 patients in eight studies were treated with autologous stem cells. Improvements in endometrial thickness and pregnancy rates after intrauterine device treatment were compared between the autologous and allogeneic stem cell groups. Endometrial thickness increased more after autologous stem cell IUA treatment (mean difference, 1.68; 95% confidence interval [CI]: 1.30–2.07; P < 0.00001), and the pregnancy rate was also improved (relative risk, 1.55; 95% CI: 1.19–2.02, P < 0. 001). No obvious and serious adverse reactions were observed during stem cell therapy in either group.

Conclusions

This meta-analysis and systematic review of the results of randomized trials of autologous and allogeneic stem cell treatments for IUA suggests that autologous stem cells have a better effect in improving the endometrium thickness and pregnancy rate.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022322870.

Recent Developments in Biomaterial-Based Hydrogel as the Delivery System for Repairing Endometrial Injury

Endometrial injury caused by intrauterine surgery often leads to pathophysiological changes in the intrauterine environment, resulting in infertility in women of childbearing age. However, clinical treatment strategies, especially for moderate to severe injuries, often fail to provide satisfactory therapeutic effects and pregnancy outcomes. With the development of reproductive medicine and materials engineering, researchers have developed bioactive hydrogel materials, which can be used as a physical anti-adhesion barrier alone or as functional delivery systems for intrauterine injury treatment by loading stem cells or various active substances. Studies have demonstrated that the biomaterial-based hydrogel delivery system can provide sufficient mechanical support and improve the intrauterine microenvironment, enhance the delivery efficiency of therapeutic agents, prolong intrauterine retention time, and perform efficiently targeted repair compared with ordinary drug therapy or stem cell therapy. It shows the promising application prospects of the hydrogel delivery system in reproductive medicine. Herein, we review the recent advances in endometrial repair methods, focusing on the current application status of biomaterial-based hydrogel delivery systems in intrauterine injury repair, including preparation principles, therapeutic efficacy, repair mechanisms, and current limitations and development perspectives.

Hysteroscopic resection for management of early pregnancy loss: a case report and literature review

Objective

To report a case of early pregnancy loss successfully managed by hysteroscopic resection, review the literature comparing hysteroscopic resection to dilation and curettage for retained products of conception, and review potential advantages of hysteroscopic resection over dilation and curettage for management of early pregnancy loss.

Design

Case report.

Setting

Private practice.

Patient(s)

One woman with early pregnancy loss.

Intervention(s)

Hysteroscopic resection using a mechanical morcellation device.

Main Outcome Measure(s)

Complete uterine evacuation after hysteroscopic resection as demonstrated by a normal transvaginal ultrasound and cessation of bleeding 2 weeks after surgery.

Result(s)

The hysteroscopic fluid deficit was 365 ml, with minimal blood loss. Products of conception were confirmed on pathologic examination. There were no intraoperative or postoperative complications. A saline infusion sonogram obtained 4 months after surgery demonstrated a normal endometrial cavity with no intrauterine adhesions.

Conclusion(s)

Surgical management of early pregnancy loss may be complicated by retained products of conception (RPOC) or intrauterine adhesion formation, which can lead to adverse fertility outcomes in the future. Hysteroscopic resection of RPOC has been associated with fewer cases of intrauterine adhesions, more cases of complete tissue removal, and earlier time to conception compared with dilation and curettage. Early pregnancy loss can also be characterized as RPOC with potentially similar benefits from hysteroscopic resection. Thus, hysteroscopic resection can be considered as an alternative surgical technique for management of early pregnancy loss. This case report demonstrates the successful application of hysteroscopic resection in a case of early pregnancy loss.

Treating intrauterine adhesion using conditionally reprogrammed physiological endometrial epithelial cells

Background

There is unmet need for effective therapies of intrauterine adhesions (IUAs) that are common cause of menstrual disturbance and infertility, since current clinical procedures do not improve prognosis for patients with moderate to severe IUA, with a recurrence rate of 23–50%. Stem cell-based therapy has emerged as a therapeutic option with unsolved issues for IUA patients in the past few years. Primary endometrial epithelial cells for cell therapy are largely hampered with the extremely limited proliferation capacity of uterine epithelial cells. This study was to evaluate whether IUA is curable with conditionally reprogrammed (CR) endometrial epithelial cells.

Methods

Mouse endometrial epithelial cells (MEECs) were isolated from C57BL female mice, and long-term cultures of MEECs were established and maintained with conditional reprogramming (CR) method. DNA damage response analysis, soft agar assay, and matrigel 3D culture were carried out to determine the normal biological characteristics of CR-MEECs. The tissue-specific differentiation potential of MEECs was analyzed with air–liquid interface (ALI) 3D culture, hematoxylin and eosin (H&E) staining, Masson’s trichrome and DAB staining, immunofluorescence assay. IUA mice were constructed and transplanted with CR-MEECs. Repair and mechanisms of MEECs transplantation in IUA mice were measured with qRT-PCR, Masson’s trichrome, and DAB staining.

Results

We first successfully established long-term cultures of MEECs using CR approach. CR-MEECs maintained a rapid and stable proliferation in this co-culture system. Our data confirmed that CR-MEECs retained normal biological characteristics and endometrium tissue-specific differentiation potential. CR-MEECs also expressed estrogen and progesterone receptors and maintained the exquisite sensitivity to sex hormones in vitro. Most importantly, allogeneic transplantation of CR-MEECs successfully repaired the injured endometrium and significantly improved the pregnancy rate of IUA mice.

Conclusions

Conditionally reprogrammed physiological endometrial epithelial cells provide a novel strategy in IUA clinics in a personalized or generalized manner and also serve as a physiological model to explore biology of endometrial epithelial cells and mechanisms of IUA.

Pregnancy Patterns Impact Live Birth Rate for Patients With Intrauterine Adhesions After Hysteroscopic Adhesiolysis: A Retrospective Cohort Study

Objective

The pregnancy patterns and other factors of live birth for patients with intrauterine adhesions (IUAs) were identified by analyzing the clinical features of pre-, intra-, and post-hysteroscopic adhesiolysis (HA).

Design

A total of 742 patients with IUAs who wanted to become pregnant underwent HA from January 2017 to May 2018 at the Third Xiangya Hospital of Central South University. The patient follow-up period was 2 years post-HA. A logistic regression was performed to analyze the clinical characteristics associated with a live birth for patients with IUAs. Pre-operative clinical indicators included age, gravidity, parity, abortion, IUA recurrence, menstrual patterns, disease course. Intraoperative clinical features assessed in the last operation were uterine cavity length, IUA appearance, IUA area, number of visible uterine cornua, number of visible tubal ostia, AFS scores. Pregnancy patterns were post-hysteroscopic adhesiolysis features.

Results

Among the 742 IUA patients, 348 (46.9%) had a live birth and 394 (53.1%) did not. A bivariate and binary logistic regression analysis showed that IUA patients’ pregnancy patterns, age, number of visible tubal ostia noted by a second-look hysteroscopy, and American Fertility Society (AFS) scores were significantly related to the live birth rate (P < 0.05).

Conclusions

Pregnancy patterns, age, number of visible tubal ostia, and AFS scores were significantly related to the live birth rate and may be considered potential predictors of the live birth rate in IUA patients. The indications of assisted reproductive technology (ART) might be a better choice for patients with recurrent IUAs.

Genetically engineered FGF1-sericin hydrogel material treats intrauterine adhesion and restores fertility in rat

Endometrial injury can cause intrauterine adhesions (IUA) and induce the formation of endometrial fibrosis, leading to infertility and miscarriage. At present, there is no effective treatment method for severe IUA and uterine basal injury with adhesion area larger than 1/3 of the uterus. In this study, we prepared FGF1 silk sericin hydrogel material (FGF1-SS hydrogel) to treat endometrial injury and prevent endometrial fibrosis. Compared with the silk sericin hydrogel material (WT-SS hydrogel), FGF1-SS hydrogel significantly promotes the cell migration and infiltration ability of endometrial stromal cells (ESCs). More importantly, FGF1-SS hydrogel can release FGF1 stably for a long time and inhibit The ESCs injury model forms fibrosis through the TGF-β/Smad pathway. In the IUA rat model, FGF1-SS hydrogel treatment effectively restored the number of uterine glands and uterine wall thickness in rats, with a fertility rate of 65.1 ± 6.4%. The results show that FGF1-SS hydrogel is expected to be a candidate to prevent IUA.

Uterine Transplantation: Recipient Patient Populations

Uterine transplantation is an emerging treatment for patients with uterine factor infertility (UFI). In order to determine patient candidacy for transplant, it is imperative to understand how to identify, counsel and treat uterine transplant recipients. In this article, we focus on patient populations with UFI, whether congenital or acquired, including Mayer-Rokitansky-Kuster-Hauser, complete androgen insensitivity syndrome, hysterectomy, and other causes of nonabsolute UFI. Complete preoperative screening of recipients should be required to assess the candidacy of each individual prior to undergoing this extensive treatment option.

Therapeutic Potential of Menstrual Blood-Derived Stem Cell Transplantation for Intrauterine Adhesions

An increasing number of women experience intrauterine adhesion as a result of intrauterine operations, such as induced abortion, which can cause infertility, recurrent abortion and amenorrhea. Although some strategies have been applied clinically, such as hysteroscopy adhesiolysis of intrauterine adhesions, the results have not been promising. As regenerative medicine develops, research on menstrual blood-derived stem cell transplantation is increasing due to the properties of these cells, including self-renewal, differentiation, angiogenesis, anti-inflammation and immunomodulation. As a result, menstrual blood-derived stem cells may be an ideal cell source for the treatment of intrauterine adhesion. Excitingly, it has been reported that autologous menstrual blood stem cells could recovery injured endometrium and improve infertility in patients with refractory intrauterine adhesion. In this review, we discuss the possible potential of menstrual blood-derived stem cell transplantation for intrauterine adhesion, including the antifibrosis, angiogenesis, anti-inflammation and immunoregulation properties of the cells, which brings hopes for clinical therapy.

A Novel Xeno-Free Method to Isolate Human Endometrial Mesenchymal Stromal Cells (E-MSCs) in Good Manufacturing Practice (GMP) Conditions

The cyclic regeneration of human endometrium is guaranteed by the proliferative capacity of endometrial mesenchymal stromal cells (E-MSCs). Due to this, the autologous infusion of E-MSCs has been proposed to support endometrial growth in a wide range of gynecological diseases. We aimed to compare two different endometrial sampling methods, surgical curettage and vacuum aspiration biopsy random assay (VABRA), and to validate a novel xeno-free method to culture human E-MSCs. Six E-MSCs cell samples were isolated after mechanical tissue homogenization and cultured using human platelet lysate. E-MSCs were characterized for the colony formation capacity, proliferative potential, and multilineage differentiation. The expression of mesenchymal and stemness markers were tested by FACS analysis and real-time PCR, respectively. Chromosomal alterations were evaluated by karyotype analysis, whereas tumorigenic capacity and invasiveness were tested by soft agar assay. Both endometrial sampling techniques allowed efficient isolation and expansion of E-MSCs using a xeno-free method, preserving their mesenchymal and stemness phenotype, proliferative potential, and limited multi-lineage differentiation ability during the culture. No chromosomal alterations and invasive/tumorigenic capacity were observed. Herein, we report the first evidence of efficient E-MSCs isolation and culture in Good Manufacturing Practice compliance conditions, suggesting VABRA endometrial sampling as alternative to surgical curettage.

Gene silencing by EZH2 suppresses TGF-β activity within the decidua to avert pregnancy-adverse wound healing at the maternal-fetal interface

A little-appreciated feature of early pregnancy is that embryo implantation and placental outgrowth do not evoke wound-healing responses in the decidua, the specialized endometrial tissue that surrounds the conceptus. Here, we provide evidence that this phenomenon is partly due to an active program of gene silencing mediated by EZH2, a histone methyltransferase that generates repressive histone 3 lysine 27 trimethyl (H3K27me3) histone marks. We find that pregnancies in mice with EZH2-deficient decidual stromal cells frequently fail by mid-gestation, with the decidua showing ectopic myofibroblast formation, peri-embryonic collagen deposition, and gene expression profiles associated with transforming growth factor β (TGF-β)-driven fibroblast activation and fibrogenic extracellular matrix (ECM) remodeling. Analogous responses are observed when the mutant decidua is surgically wounded, while blockade of TGF-β receptor signaling inhibits the defects and improves reproductive outcomes. Together, these results highlight a critical feature of reproductive success and have implications for the context-specific control of TGF-β-mediated wound-healing responses elsewhere in the body.

Cell-based therapy in thin endometrium and Asherman syndrome

Numerous treatment strategies have so far been proposed for treating refractory thin endometrium either without or with the Asherman syndrome. Inconsistency in the improvement of endometrial thickness is a common limitation of such therapies including tamoxifen citrate as an ovulation induction agent, acupuncture, long-term pentoxifylline and tocopherol or tocopherol only, low-dose human chorionic gonadotropin during endometrial preparation, aspirin, luteal gonadotropin-releasing hormone agonist supplementation, and extended estrogen therapy. Recently, cell therapy has been proposed as an ideal alternative for endometrium regeneration, including the employment of stem cells, platelet-rich plasma, and growth factors as therapeutic agents. The mechanisms of action of cell therapy include the cytokine induction, growth factor production, natural killer cell activity reduction, Th17 and Th1 decrease, and Treg cell and Th2 increase. Since cell therapy is personalized, dynamic, interactive, and specific and could be an effective strategy. Despite its promising nature, further research is required for improving the procedure and the safety of this strategy. These methods and their results are discussed in this article.

3D-printed hydrogel scaffold-loaded granulocyte colony-stimulating factor sustained-release microspheres and their effect on endometrial regeneration

After injury, the endometrium cannot self-repair or regenerate because damages of the basal layer of the uterine, which often lead to intrauterine adhesions (IUAs), which can cause serious problems such...

Stem Cell Therapies for Human Infertility: Advantages and Challenges

Physical and mental health and hormonal imbalance are associated with the problems related to infertility and reproductive disorders. The rate of infertility has increased globally over the years, due to various reasons. Given the psychosocial implications of infertility and its effects on the life of the affected people, there has been an increased focus on its treatment over the last several years. Assisted reproductive technology can only solve about 50% of the cases. Moreover, it contains significant risks and does not solve the fundamental problem of infertility. As pluripotent stem cells have the potential to differentiate into almost any type of cell, they have been widely regarded as a promising option in the development of stem cell-based fertility treatments, which could even correct genetic diseases in offspring. These advancements in reproductive biotechnology present both challenges and possibilities for solving infertility problems caused by various unexplainable factors. This review briefly presents the different types of infertility disorders and the potential applications of stem cells in the treatment of these reproductive diseases.

Making More Womb: Clinical Perspectives Supporting the Development and Utilization of Mesenchymal Stem Cell Therapy for Endometrial Regeneration and Infertility

The uterus is a homeostatic organ, unwavering in the setting of monthly endometrial turnover, placental invasion, and parturition. In response to ovarian steroid hormones, the endometrium autologously prepares for embryo implantation and in its absence will shed and regenerate. Dysfunctional endometrial repair and regeneration may present clinically with infertility and abnormal menses. Asherman's syndrome is characterized by intrauterine adhesions and atrophic endometrium, which often impacts fertility. Clinical management of infertility associated with abnormal endometrium represents a significant challenge. Endometrial mesenchymal stem cells (MSC) occupy a perivascular niche and contain regenerative and immunomodulatory properties. Given these characteristics, mesenchymal stem cells of endometrial and non-endometrial origin (bone marrow, adipose, placental) have been investigated for therapeutic purposes. Local administration of human MSC in animal models of endometrial injury reduces collagen deposition, improves angiogenesis, decreases inflammation, and improves fertility. Small clinical studies of autologous MSC administration in infertile women with Asherman's Syndrome suggested their potential to restore endometrial function as evidenced by increased endometrial thickness, decreased adhesions, and fertility. The objective of this review is to highlight translational and clinical studies investigating the use of MSC for endometrial dysfunction and infertility and to summarize the current state of the art in this promising area.

Metabolomics and pharmacodynamic analysis reveal the therapeutic role of Prunella vulgaris oil on intrauterine adhesion rats

Metabolomics is applied to explore the curative effect of complex systems, such as Chinese medicine. Intrauterine adhesion (IUA) harms the reproductive system and affects fertility, and hence is a significant public health concern. Prunella vulgaris oil (PVO) protects the reproductive system and exerts anti-inflammatory effects, but its effect on IUA and the underlying mechanism is unclear. In this study, we established a serum metabolomics method based on GC-TOF-MS to evaluate the mechanism of PVO in the IUA rat model established by mechanical injury and infection. Animal experiments showed that PVO improves the inflammatory response in the uterus of IUA model rats and reduces the content of inflammatory factors to improve the microenvironment of the reproductive system. It also regulates the expression of TGF-β1 and Smad-related mRNA and protein to inhibit fibrosis. Metabolomics indicated a significant abnormality in serum metabolism in IUA rats, and a total of 51 differential markers were screened and identified. After PVO treatment, these metabolic abnormalities improved significantly. The metabolic pathway analysis revealed that PVO affects glyoxylate and dicarboxylate metabolism, and β-alanine metabolism pathways. This study showed that PVO significantly improves inflammation and fibrosis in IUA rats combined with the pharmacological results. The primary mechanism is related to regulating the metabolism of amino acids and their derivatives to balance the associated disorders and control energy metabolism.

The Latest Developments in Immunomodulation of Mesenchymal Stem Cells in the Treatment of Intrauterine Adhesions, Both Allogeneic and Autologous

Intrauterine adhesion (IUA) is an endometrial fibrosis disease caused by repeated operations of the uterus and is a common cause of female infertility. In recent years, treatment using mesenchymal stem cells (MSCs) has been proposed by many researchers and is now widely used in clinics because of the low immunogenicity of MSCs. It is believed that allogeneic MSCs can be used to treat IUA because MSCs express only low levels of MHC class I molecules and no MHC class II or co-stimulatory molecules. However, many scholars still believe that the use of allogeneic MSCs to treat IUA may lead to immune rejection. Compared with allogeneic MSCs, autologous MSCs are safer, more ethical, and can better adapt to the body. Here, we review recently published articles on the immunomodulation of allogeneic and autologous MSCs in IUA therapy, with the aim of proving that the use of autologous MSCs can reduce the possibility of immune rejection in the treatment of IUAs.

The potential of Zishen Yutai pills to facilitate endometrial recovery and restore fertility after induced abortion in rats

CONTEXT

Abortions damage the endometrium in women. Currently, therapeutic options for endometrial recovery are limited. Zishen Yutai Pill (ZYP) was found to promote endometrial blood supply as a traditional Chinese medicine. However, whether ZYP promotes endometrial recovery post-abortion has not yet been explored.

OBJECTIVE

This study evaluated the role of ZYP in rat endometrial recovery after induced abortion and explored its mechanism of action.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into three groups: no-operation group, control group, and ZYP group. The rats in the control and ZYP group were induced abortion, and then treated with normal saline or ZYPs, respectively, for 1-3 oestrous cycles. Morphological changes in the endometrium were examined. Expression levels of the factors related to endometrial recovery were analyzed. The duration of this study was almost seven months.

RESULTS

The endometrial thickness (7.3 ± 0.17 mm) and number of glands (5.5 ± 0.20) increased significantly in the ZYP group compared with those in the control group (5.5 ± 0.15 mm and 3.5 ± 0.18; p < 0.05). Fibrosis of the endometrium was ameliorated by ZYP administration (45 ± 6% vs. 58 ± 7%; p < 0.05). ZYPs treatment increased the expression of VEGF, ER, MMP-9, LIF, and HB-EGF, but decreased TGF-β expression. Moreover, the average number of pups in the ZYP group (9.0 ± 1.5) was greater than that in the control (4 ± 1.3).

DISCUSSION AND CONCLUSION

ZYPs accelerate endometrial recovery and restored fertility in rats, suggesting its potential to promote human endometrial repair.

Clinical application of three-dimensional transvaginal ultrasonography in the diagnosis of intrauterine adhesions

Objective

The present study aimed to evaluate the diagnostic accuracy of three-dimensional transvaginal ultrasonography (3D-TVS) for intrauterine adhesions (IUA).

Methods

We performed a retrospective cohort study. A total of 500 women aged 19 to 46 years with uterine lesions who received treatment from the Department of Obstetrics and Gynecology were enrolled. Endometrial 3D imaging was conducted to obtain the display plane and 3D-TVS parameters. Patients also underwent hysteroscopy for a definitive diagnosis.

Results

For diagnosing IUA, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy of 3D-TVS were 98.8%, 90.8%, 91.4%, 98.7%, and 94.8%, respectively. For diagnosing a submucosal myoma, the sensitivity, specificity, PPV, NPV, and overall accuracy of 3D-TVS were 88.2%, 97.9%, 88.2%, 97.9%, and 96.4%, respectively. For diagnosing endometrial polyps, the sensitivity, specificity, PPV, NPV, and overall accuracy of 3D-TVS were 94.7%, 96.8%, 92.9%, 97.7%, and 96.2%, respectively.

Conclusions

Before hysteroscopy, 3D-TVS, as a method of screening, has great value for comparing differences before and after treatment, and for evaluating therapeutic effects.

Management of intrauterine adhesions using human amniotic mesenchymal stromal cells to promote endometrial regeneration and repair through Notch signalling

Intrauterine adhesions (IUAs) severely hamper women's reproductive functions. Human amniotic mesenchymal stromal cell (hAMSC) transplantation is effective in treating IUAs. Here, we examined the function of Notch signalling in IUA treatment with hAMSC transplantation. Forty-five Sprague-Dawley female rats were randomly divided into the sham operation, IUA, IUA + E2, IUA + hAMSCs and IUA + hAMSCs + E2 groups. After IUA induction in the rats, hAMSCs promoted endometrial regeneration and repair via differentiation into endometrial epithelial cells. In all groups, the expression of key proteins in Notch signalling was detected in the uterus by immunohistochemistry. The results indicated Notch signalling activation in the hAMSCs and hAMSCs + E2 groups. We could also induce hAMSC differentiation to generate endometrial epithelial cells in vitro. Furthermore, the inhibition of Notch signalling using the AdR-dnNotch1 vector suppressed hAMSC differentiation (assessed by epithelial and mesenchymal marker levels), whereas its activation using the AdR-Jagged1 vector increased differentiation. The above findings indicate Notch signalling mediates the differentiation of hAMSCs into endometrial epithelial cells, thus promoting endometrial regeneration and repair; Notch signalling could have an important function in IUA treatment.

Autologous platelet-rich plasma treatment for moderate-severe Asherman syndrome: the first experience

PURPOSE

Treatment of Asherman syndrome (AS) presents a significant clinical challenge. Based on our in vitro data showing that PRP could activate endometrial cell proliferation and migration, we hypothesized that intrauterine infusion of autologous platelet-rich plasma (PRP) may improve endometrial regeneration and fertility outcomes in patients with moderate-severe AS.

MATERIALS AND METHODS

Subjects with moderate-severe AS were randomized to PRP or saline control administered following hysteroscopic adhesiolysis. Due to relative inability to randomize patients to the control group, after initial randomization of 10 subjects (6 in PRP and 4 in control groups), the remainder were prospectively enrolled in PRP group (n = 9), with 11 historic controls added to control group, for a total of 30 subjects (PRP n = 15; saline control n = 15). Right after hysteroscopy, 0.5-1 mL of PRP or saline was infused into the uterus via a Wallace catheter, followed by estrogen therapy. The primary outcomes were changes in endometrial thickness (EMT, checked in 3 weeks) and in menstrual flow; secondary outcomes were pregnancy and live birth rates. EMT and menstrual bleeding pattern were assessed before and after the intervention. Pregnancy was assessed over a 6-month period.

RESULTS

There were no statistically significant differences in age, gravidity/parity, cause of AS, preoperative menses assessment, AS hysteroscopy score, and intrauterine balloon placement between the groups. There was no statistically significant difference (p = 0.79) in EMT pre-PRP infusion for control (5.7 mm, 4.0-6.0) and study arm (5.3 mm, 4.9-6.0). There was no statistically significant change (p = 0.78) in EMT after PRP infusion (1.4 mm, - 0.5-2.4) vs saline (1.0 mm, 0.0-2.5). Patients tolerated the procedure well, with no adverse effects. There was no difference in the predicted likelihood of pregnancy (p = 0.45) between the control (0.67, 0.41-0.85) and study arm (0.53, 0.29-0.76).

CONCLUSIONS

PRP was well accepted and tolerated in AS patients. However, we did not observe any significant EMT increase or improved pregnancy rates after adding PRP infusion, compared to standard treatment only. The use of intrauterine PRP infusion may be a feasible option, and its potential use must be tested on a larger sample size of AS patients.

Uterine adhesion: Is luteal phase prior to follicular phase in uterine adhesiolysis?

To compare the patients' outcomes of Asherman syndrome who underwent uterine adhesiolysis in luteal phase or follicular phase.A retrospective cohort study.A tertiary hospital in China.Four hundred sixty-four women suffered intrauterine adhesion who underwent monopolar adhesiolysis from March 2014 to March 2017 were analyzed. One hundred seventy-eight patients underwent operations in follicular phase (OFP) and 286 underwent operations in luteal phase (OLP).Hormone therapy was accompanied with an intrauterine device and a second-look hysteroscopy was performed postoperatively.Endometrial thickness in women was analyzed by a transvaginal 3-dimensional ultrasound examination. Re-adhesion was confirmed by a second-look hysteroscopy 3 months after hysteroscopic adhesiolysis. Pregnancy rate was acquired by questionnaires 3 months after a second-look hysteroscopy.OLP has advantages with thicker luteal endometrium (P = .001), higher pregnancy rates (P < .001), and lower re-adhesion rates (P = 0015) compared to these values of OFP.For Asherman syndrome, our study showed that OLP is more feasible than OFP in intrauterine adhesiolysis.

Hydrogel, a novel therapeutic and delivery strategy, in the treatment of intrauterine adhesions

Intrauterine adhesions (IUAs) are caused by damage to the underlying lining of the endometrium. They' re related to disorder of endometrial repair. In recent years, hydrogels with controllable biological activity have been widely used for treating IUAs. They encapsulate estrogen, cytokines, cells, or exosomes, forming a delivery system to release therapeutic components for the treatment of IUAs. In addition, the hydrogel acting as a barrier can be degraded in the body automatically, reducing the risk of infection caused by secondary surgeries. In this review, we summarize the recent progress of hydrogels and their application in IUAs as both a novel alternative therapeutic and an artificial delivery strategy.

Therapeutic Role of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Female Reproductive Diseases

Reproductive disorders, including intrauterine adhesion (IUA), premature ovarian insufficiency (POI), and polycystic ovary syndrome (PCOS), are great threats to female reproduction. Recently, mesenchymal stem cells derived-extracellular vesicles (MSC-EVs) have presented their potentials to cure these diseases, not only for the propensity ability they stemmed from the parent cells, but also for the higher biology stability and lower immunogenicity, compared to MSCs. EVs are lipid bilayer complexes, functional as mediators by transferring multiple molecules to recipient cells, such as proteins, microRNAs, lipids, and cytokines. EVs appeared to have a therapeutic effect on the female reproductive disorder, such as repairing injured endometrium, suppressing fibrosis of endometrium, regulating immunity and anti-inflammatory, and repressing apoptosis of granulosa cells (GCs) in ovaries. Although the underlying mechanisms of MSC-EVs have reached a consensus, several theories have been proposed, including promoting angiogenesis, regulating immunity, and reducing oxidate stress levels. In the current study, we summarized the current knowledge of functions of MSC-EVs on IUA, POI, and PCOS. Given the great potentials of MSC-EVs on reproductive health, the critical issues discussed will guide new insights in this rapidly expanding field.

Improved Models of Human Endometrial Organoids Based on Hydrogels from Decellularized Endometrium

Organoids are three-dimensional (3D) multicellular tissue models that mimic their corresponding in vivo tissue. Successful efforts have derived organoids from primary tissues such as intestine, liver, and pancreas. For human uterine endometrium, the recent generation of 3D structures from primary endometrial cells is inspiring new studies of this important tissue using precise preclinical models. To improve on these 3D models, we decellularized pig endometrium containing tissue-specific extracellular matrix and generated a hydrogel (EndoECM). Next, we derived three lines of human endometrial organoids and cultured them in optimal and suboptimal culture expansion media with or without EndoECM (0.01 mg/mL) as a soluble additive. We characterized the resultant organoids to verify their epithelial origin, long-term chromosomal stability, and stemness properties. Lastly, we determined their proliferation potential under different culture conditions using proliferation rates and immunohistochemical methods. Our results demonstrate the importance of a bioactive environment for the maintenance and proliferation of human endometrial organoids.

Role of hyaluronic acid intrauterine injection in the prevention of Asherman's syndrome in women undergoing uterine septum resection: An RCT

Background

Adhesion due to intrauterine surgery such as septal resection associated with damaged endometrium can increase the risk of Asherman's syndrome. The main goal of treatment in this syndrome is to repair the damaged endometrium for creating a physiological pregnancy.

Objective

To investigate the effect of intrauterine injection of hyaluronic acid on the prevention of Asherman's syndrome in women undergoing uterine septum resection.

Materials and Methods

In this double-blind randomized clinical trial, 65 women undergoing the uterine septum resection were divided into two groups; the case group (n = 34) and the control group (n = 31). Immediately after the septal resection with a resectoscope, 1cc of hyaluronic acid gel in the case group and 1cc normal saline solution as a placebo in the control group was injected into the uterine cavity. After two months, existence of intrauterine adhesions in the both groups was examined by the hysteroscope and assessment of menstrual patterns, according to the American Society for Reproductive Medicine criteria.

Results

Our results showed that after intervention, the incidence of Asherman's syndrome in the control group was higher than the case group (p = 0.012). In the case group, only four women had poor adhesion (Asherman's syndrome) at the end of the study, while the rest of them were free of any adhesions in the uterine cavity. In the control group, however, only 19 were free of intrauterine adhesions and 12 had mild symptoms.

Conclusion

The results of the study exhibited the hyaluronic acid capacity to reduce the risk of Asherman's syndrome in women with endometrial damage following a septal resection surgery.

Endometrial membrane organoids from human embryonic stem cell combined with the 3D Matrigel for endometrium regeneration in asherman syndrome

Asherman's syndrome (AS), a leading cause of uterine infertility worldwide, is characterized by scarring of the uterine surfaces lacking endometrial epithelial cells, which prevents endometrial regeneration. Current research on cell therapy for AS focuses on mesenchymal and adult stem cells from the endometrium. However, insufficient number, lack of purity, and rapid senescence of endometrial epithelial progenitor cells (EEPCs) during experimental processes restrict their use in cell therapies. In this study, we induced human embryonic stem cells-9 (H9-ESC) into EEPCs by optimizing the induction factors from the definitive endoderm. EEPCs, which act as endometrial epithelial cells, accompanied by human endometrial stromal cells provide a niche environment for the development of endometrial membrane organoids (EMOs) in an in vitro 3D culture model. To investigate the function of EMOs, we transplanted tissue-engineered constructs with EMOs into an in vivo rat AS model. The implantation of EMOs into the damaged endometrium facilitates endometrial regeneration and angiogenesis. Implanting EMOs developed from human embryonic stem cells into the endometrium might prove useful for "endometrial re-engineering" in the treatment of Asherman's syndrome.

Expression and significance of estrogen receptor and progesterone receptor in endometrial tissue of patients with intrauterine adhesions

Background

Our study aims to analyze the expression and significance of estrogen receptor (ER) and progesterone receptor (PR) in endometrial tissues of patients with intrauterine adhesion (IUA).

Methods

Fifty-four patients with IUAs examined in our hospital from January 2017 to January 2019 were selected as the research object (observation group), 54 healthy women who had physical examinations during the same period were selected as the control group, and the immunohistochemical EnVision was used. Two-step and real-time fluorescent quantitative PCR methods were used to detect the expression levels of ER and PR in the endometrial tissues of the two groups of subjects.

Results

The immunohistochemical test results showed that ER's expression level in the observation group was significantly higher than that in the control group, and the difference between the two groups was statistically significant (P<0.05). The difference in PR expression levels between the two groups was insignificant (P<0.05). Real-time fluorescent quantitative PCR results showed ER and PR's expression levels in the observation group were significantly higher than those in the control group, and the difference between the two groups was statistically significant (P<0.05).

Conclusions

After IUA can detect ER and PR expression, we can formulate a personalized hormone treatment plan to improve the clinical treatment effect.

Recent developments in bio-scaffold materials as delivery strategies for therapeutics for endometrium regeneration

Intrauterine adhesions (IUAs) refer to the repair disorder after endometrial injury and may lead to uterine infertility, recurrent miscarriage, abnormal menstrual bleeding, and other obstetric complications. It is a pressing public health issue among women of childbearing age. Presently, there are limited clinical treatments for IUA, and there is no sufficient evidence that these treatment modalities can effectively promote regeneration after severe endometrial injury or improve pregnancy outcome. The inhibitory pathological micro-environment is the main factor hindering the repair of endometrial damaged tissues. To address this, tissue engineering and regenerative medicine have been achieving promising developments. Particularly, biomaterials have been used to load stem cells or therapeutic factors or construct an in situ delivery system as a treatment strategy for endometrial injury repair. This article comprehensively discusses the characteristics of various bio-scaffold materials and their application as stem cell or therapeutic factor delivery systems constructed for uterine tissue regeneration.

Anti-adhesion Gel versus No gel following Operative Hysteroscopy prior to Subsequent fertility Treatment or timed InterCourse (AGNOHSTIC), a randomised controlled trial: protocol

STUDY QUESTIONS

Does the application of anti-adhesion gel, compared to no gel, following operative hysteroscopy to treat intrauterine pathology in women wishing to conceive increase the chance of conception leading to live birth?

WHAT IS KNOWN ALREADY

Intrauterine adhesions (IUAs) following operative hysteroscopy may impair reproductive success in women of reproductive age. Anti-adhesion barrier gels may decrease the occurrence of IUAs, but the evidence on their effectiveness to improve reproductive outcomes is sparse and of low quality.

STUDY DESIGN SIZE DURATION

This multicentre, parallel group, superiority, blinded and pragmatic randomised controlled trial is being carried out in seven participating centres in Belgium. Recruitment started in April 2019. Women will be randomly allocated to treatment with anti-adhesion gel (intervention group) or no gel (control group). Sterile ultrasound gel will be applied into the vagina as a mock-procedure in both treatment arms. The patient, fertility physician and gynaecologist performing the second-look hysteroscopy are unaware of the allocated treatment. Power analysis, based on a target improvement of 15% in conception leading to live birth using anti-adhesion gel, a power of 85%, a significance level of 5%, and a drop-out rate of 10%, yielded a number of 444 patients to be randomised. The baseline rate of conception leading to live birth in the control group is expected to be 45%.

PARTICIPANTS/MATERIALS SETTING METHODS

Women of reproductive age (18-47 years), wishing to conceive (spontaneously or by fertility treatment) and scheduled for operative hysteroscopy to treat intrauterine pathology (endometrial polyps, myomas with uterine cavity deformation, uterine septa, IUAs or retained products of conception) are eligible for recruitment. Women may try to conceive from 3 to 6 weeks after receiving allocated treatment with follow-up ending at 30 weeks after treatment. If the woman fails to conceive within this timeframe, a second-look hysteroscopy will be scheduled within 2-6 weeks to check for IUAs. The primary endpoint is conception leading to live birth, measured at 30 weeks after randomisation. The secondary endpoints are time to conception, clinical pregnancy, miscarriage and ectopic pregnancy rates, measured at 30 weeks after receiving allocated treatment. The long-term follow-up starts when the patient is pregnant and she will be contacted every trimester.

STUDY FUNDING/COMPETING INTERESTS

This work is funded by the Belgian Healthcare Knowledge Centre (KCE). The anti-adhesion gel is supplied at no cost by Nordic Pharma and without conditions. Dr. Tomassetti reports grants and non-financial support from Merck SA, non-financial support from Ferring SA, personal fees and non-financial support from Gedeon-Richter, outside the submitted work. None of the other authors have a conflict of interest.

HMGA2-induced epithelial-mesenchymal transition is reversed by let-7d in intrauterine adhesions

Intrauterine adhesions (IUAs), the leading cause of uterine infertility, are characterized by endometrial fibrosis. The management of IUA is challenging because the pathogenesis of the disease largely unknown. In this study, we demonstrate that the mRNA and protein levels of high mobility group AT-hook 2 (HMGA2) were increased by nearly 3-fold (P < 0.0001) and 5-fold (P = 0.0095) in the endometrial epithelial cells (EECs) of IUA patients (n = 18) compared to controls. In vivo and in vitro models of endometrial fibrosis also confirmed the overexpression of HMGA2 in EECs. In vitro cell experiments indicated that overexpression of HMGA2 promoted the epithelial-mesenchymal transition (EMT) while knockdown of HMGA2 reversed transforming growth factor-β-induced EMT. A dual luciferase assay confirmed let-7d microRNA downregulated HMGA2 and repressed the pro-EMT effect of HMGA2 in vitro and in vivo. Therefore, our data reveal that HMGA2 promotes IUA formation and suggest that let-7d can depress HMGA2 and may be a clinical targeting strategy in IUA.

Predictive value of live birth rate based on different intrauterine adhesion evaluation systems following TCRA

OBJECTIVE

The aim of this study was to assess the predictive value of five different intrauterine adhesion (IUA) evaluation systems for live birth rate following transcervical resection of adhesion (TCRA).

METHOD

This retrospective study included 128 women with IUA who desired for spontaneous conception after TCRA. All the patients were retrospectively scored by the American Fertility Society (AFS) classification, European Society of Gynecological Endoscopy (ESGE) classification, March's classification (March), Nasr classification (Nasr) and Chinese IUA diagnosis classification criteria (Chinese). The predictive value of these evaluation systems was determined by receiver operating characteristic (ROC) curves and area under a ROC curve (AUC).

RESULTS

The correlation coefficients of AFS, ESGE, March, Nasr and Chinese classification and the live birth rate were 0.313, 0.313, 0.288, 0.380, and 0.336, respectively. Among women with hypomenorrhea and amenorrhea, as well as women with no infertility, the severities determined by all five evaluation systems were correlated with live birth rate (P <  0.001). All five scoring systems were efficient to predict live birth rate. Among them, Nasr classification showed the highest AUC (0.748) with the best predictive value. Multivariate logistic regression analyses showed that Nasr classification had the highest OR (OR, 6.523; 95% CI, 2.612, 18.263). And, Nasr's classification system also showed highest sensitivity (81.8%) and negative predictive value (96.7%) when divide the system into mild IUA vs. moderate and severe IUA.

CONCLUSION

AFS, ESGE, March, Nasr and Chinese classification were demonstrated to be capable of predicting live birth following TCRA although the predictive capacities might be limited, and Nasr classification showed the highest predictive value of live birth.

Identifying the risk factors and incidence of Asherman Syndrome in women with post-abortion uterine curettage

AIM

To evaluate the risk factors and incidence of Asherman Syndrome in women with post-abortion uterine evacuation and curettage.

METHODS

A total of 2546 patients who had surgical abortion (uterine evacuation and curettage) before the 20th gestational week with indications of missed abortion, anembryonic pregnancy, incomplete abortion, and elective curettage in a tertiary antenatal care center were recruited. The patients were called and surveyed for their symptoms; including infertility, oligo-amenorrhea and recurrent pregnancy loss, preterm birth and intrauterine growth retardation and abnormal placentation as criteria of Asherman Syndrome. Diagnostic (office) hysteroscopy was performed for 177 who had one of those complaints.

RESULTS

The incidence of Asherman Syndrome was 1.6% (n = 43/2546). History of ≥3 abortions was the main factor that increased the risk of Asherman Syndrome for by 4.6 times. Use of vacuum aspiration or sharp curettage, premedication for cervical priming, and having a pregnancy >10th gestational weeks were not risk factors for Asherman Syndrome.

CONCLUSION

When the diagnosis was based on presence of symptoms who underwent uterine instrumentation, the incidence of Asherman Syndrome was found to be 1.6%. Repeated abortions were the main risk factor for Asherman Syndrome and avoiding from repeated uterine instrumentations may have a role in prevention.

Patient-reported menstrual and obstetric outcomes following hysteroscopic adhesiolysis for Asherman syndrome

Objective

Review the menstrual and obstetric outcomes among Asherman syndrome patients when stratified by disease severity.

Design

Retrospective cohort study.

Setting

A community teaching hospital affiliated with a large academic medical center.

Patients

A total of 355 Asherman syndrome patients stratified by March classification who underwent hysteroscopic adhesiolysis.

Interventions

Telephone survey, analyzed with multivariable analysis.

Main Outcome Measures

Return of menstruation. Pregnancy, miscarriage, and live birth rate.

Results

A total of 355 patients underwent hysteroscopic adhesiolysis. Of these, 150 (42.3%) patients completed the telephone survey with a mean follow-up of 2.21 years. Additionally, 40.7% had mild, 52.7% had moderate, and 6.6% had severe disease. Furthermore, 25.3% of patients reported amenorrhea at presentation, with mild disease patients having the highest rate of returning menstruation (93.8%) following treatment. The cumulative pregnancy rate was 81.9%, and the cumulative live birth rate was 51.2%, with no statistical differences identified by the classification group.

Conclusion

Asherman syndrome disease severity predicted returning menstruation but not pregnancy or live birth rate.

Definition and Multiple Factors of Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is usually defined as three or more spontaneous abortions prior to 20-28 weeks gestation. RSA affects approximately 2-5% of all women of childbearing age, and it brings tremendous psychological and psychiatric trauma to the women and also results in economic burden. The causes could be female age, anatomical and chromosomal abnormalities, genetic, endocrinological, placental anomalies, infection, smoking and alcohol consumption, psychological factor, exposure to environmental factors such as heavy metal, environment pollution, and radiation.

LncRNA HOTAIR promotes endometrial fibrosis by activating TGF-β1/Smad pathway

Homeobox transcript antisense RNA (HOTAIR) is a long non-coding RNA associated with a number of fibrosis-related diseases. The aim of this study was to investigate the specific role of HOTAIR in the development of endometrial fibrosis and to identify the molecular mechanisms underlying this process. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine the expression levels of HOTAIR in samples of intrauterine adhesion (IUA) tissue and in endometrial stromal cells (ESCs) that had been treated with transforming growth factor beta 1 (TGF-β1). Additionally, we transfected ESCs with either overexpression plasmid (pcDNA-HOTAIR) or silencing construct (si-HOTAIR) and then treated these cells with TGF-β1. We then performed RT-qPCR and western blot analysis, along with cell proliferation and apoptosis assays, to investigate the effects of HOTAIR on the transdifferentiation of ESCs into myofibroblasts. The results showed that the expression levels of HOTAIR were significantly elevated in IUA tissue and in ESCs that had been treated with TGF-β1. The overexpression of HOTAIR had a pro-fibrotic effect on ESCs, while the silencing of HOTAIR exerted an anti-fibrotic effect. Most importantly, the protein expression levels of p-Smad2 and p-Smad3 were significantly upregulated in TGF-β1-treated ESCs transfected with pcDNA-HOTAIR and were downregulated after transfection with si-HOTAIR constructs. These data indicate that HOTAIR promotes endometrial fibrosis by activating the TGF-β1/Smad signaling pathway, suggesting that the inhibition of HOTAIR may represent a promising therapeutic option for suppressing endometrial fibrosis.

miR-29a in Exosomes from Bone Marrow Mesenchymal Stem Cells Inhibit Fibrosis during Endometrial Repair of Intrauterine Adhesion

Background and Objectives

Bone marrow mesenchymal stem cells (BMSCs) is an ideal source of stem cells in the treatment of intrauterine adhesion. Exosomes are a type of membrane vesicle and the diameter is 30∼100 nm. Exosomes can take their contents into the target cells, releasing and exerting their functions. In this study, we intend to study the role of human BMSC-derived exosomes (BMSC-Exo) in promoting endometrial damage repair in the treatment of IUA.

Methods

We used the magnetic bead affinity method to extract BMSC-Exo and analyzed its biological character. Then we co-cultured the BMSCs-Exo with endometrial cells to detect its effect. We injected BMSCs-Exo into the IUA mouse model. We over-expressed miR-29a in BMSCs-Exo by transient transfection, then used RT-PCR to analyze the expression of the related genes.

Results

BMSCs-Exo expressed exosome-specific proteins CD9, CD63, and CD81. BMSCs-Exo could bring the contents into the target cells. BMSCs-Exo can promote endometrial repair in vitro or in vivo. BMSCs-Exo overexpressing miR-29a can reduce αSMA, Collagen I, SMAD2, and SMAD3.

Conclusions

In this study, we successfully isolated BMSCs-Exo and proved its character and biological activity. BMSCs-Exo can promote cell proliferation and cell migration in vitro and can repair damaged endometrium in the IUA model. The presence of miR-29a in BMSCs-Exo may be an important factor in its resistance to fibrosis during endometrial repair of IUA. This study provides new ideas for the treatment of patients with IUA and has important clinical research significance.

Application of Hydrogel-Based Delivery System in Endometrial Repair

A receptive endometrium with proper thickness is essential for successful embryo implantation. However, endometrial injury caused by intrauterine procedures often leads to pathophysiological changes in its environment, resulting in subsequent female infertility. Among diverse treatment methods of endometrial injury, hydrogels are a class of hydrophilic three-dimensional polymeric network with biocompatibility as well as the capability of absorbing water and encapsulation, which have potential applications as a promising intrauterine controlled-release delivery system. This review summarizes recent advances in the approaches of endometrial repair and further focuses on the application of a hydrogel-based delivery system in endometrial repair, including its preparation, therapeutic loading considerations, clinical applications, as well as working mechanisms.