Effectiveness of estrogen treatment before transcervical resection of adhesions on moderate and severe uterine adhesion patients

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.

Yangmo decoction versus hyaluronic acid gel in women with intrauterine re-adhesion after hysteroscopic adhesiolysis: a retrospective efficacy and safety analysis

BACKGROUND

Hysteroscopic adhesiolysis is the preferred primary method for intrauterine adhesion. However, there is about a 60% of chance of re-adhesion after surgery. The objectives of the study were to evaluate the efficacy and safety of Yangmo decoction as a secondary treatment in preventing intrauterine re-adhesion against those of hyaluronic acid gel.

METHODS

Women received oral Yangmo decoction (YD cohort, n = 105) or intrauterine hyaluronic acid gel (HA cohort, n = 125) or did not receive secondary re-adhesion prevention treatments (EP cohort, n = 165) after hysteroscopic adhesiolysis for 6 months. In addition, all women have received 3 mg of oral estrogen and 20 mg oral progesterone combination after hysteroscopic adhesiolysis for 3 months. Intrauterine re-adhesion after hysteroscopic adhesiolysis after 6 months with or without secondary treatment(s) was detected using hysteroscopy. The extent of the cavity, type of adhesion, and the menstrual pattern were included to define the American Fertility Society classification of intrauterine re-adhesions (AFS) score.

RESULTS

Fewer numbers of women suffered from intrauterine re-adhesion after hysteroscopic adhesiolysis in the YD cohort than those of the HA (15(14%) vs. 40(32%), p = 0.0019) and the EP (15(14%) vs. 58(35%). p = 0.0001) cohorts. Among women who developed intrauterine re-adhesion, AFS score was fewer for women of the YD cohort than those of HA (2(2-1) vs. 4(4-3), p < 0.001) and the EP (2(2-1) vs. 4(4-4), p < 0.001) cohorts. AFS score after surgery was fewer for women of the HA cohort than those of the EP cohort (p < 0.05). Higher numbers of women of the YD cohort retained pregnancies after 6-months of treatment than those of the HA (55(52%) vs. 45(36%), p = 0.0161) and EP (55(52%) vs. 35(21%), p < 0.0001) cohorts. Among women who develop re-adhesion, 10(10%) women of the YD cohort only had successful pregnancies.

CONCLUSIONS

Yangmo decoction for 6 months after hysteroscopic adhesiolysis can reduce AFS score, prevent intrauterine re-adhesion, and increases the chances of successful pregnancies of women.

LEVEL OF EVIDENCE

IV.

TECHNICAL EFFICACY

Stage 5.

Chitosan combined with intrauterine device prevents intrauterine adhesions after hysteroscopic adhesiolysis: A target trial emulation study

AIM

To compare the efficacy of chitosan and intrauterine device (IUD) combination with an IUD alone in patients with intrauterine adhesions (IUAs) who underwent hysteroscopic adhesiolysis.

METHODS

This retrospective study assessed 303 patients with moderate-to-severe IUA (American Fertility Society [AFS] score ≥5) who underwent hysteroscopic adhesiolysis between January 2018 and December 2020. Using observational data under a cohort design, we emulated a target trial with two treatment arms: chitosan plus IUD and IUD alone groups. Second-look hysteroscopy was performed in all patients 3 months after the initial hysteroscopy. The primary outcome was improved adhesion assessed using the AFS scoring system.

RESULTS

The baseline characteristics were balanced between the two groups. The second hysteroscopy revealed significantly better AFS scores in group A than in group B (values: 3 [1-4] vs. 4 [2-6], p < 0.001; change: 63% [50%-80%] vs. 44% [33%-67%], p < 0.001, respectively). Significantly better menstruation conditions (improved rate: 66% vs. 49%, p = 0.004) and endometrial thickness (mean: 7.0 mm vs. 6.0 mm, p < 0.001) were also observed in group A than in group B. Moreover, group A showed a significantly higher 1-year clinical pregnancy rate (40% vs. 28%, p = 0.037) and better quality of life (p < 0.001) than group B.

CONCLUSIONS

Chitosan and IUD combination showed better efficacy in reducing adhesions and improving clinical outcomes in patients with moderate-to-severe IUA after hysteroscopic adhesiolysis.

Evaluation of pharmacokinetics and safety of a long-term estradiol-releasing stent in rat uterine

Purpose

Intrauterine adhesion (IUA), often leading to gynecological complications including amenorrhea, abdominal pain and infertility, is frequently induced by injuries to the endometrium. Hence it would be of great benefit to take efforts to prevent adhesion after intrauterine operations. Orally administration of 17β-estradiol (E2) is commonly used to promote endometrium regeneration, but is limited by low concentrations at the injured sites. We aim at preparing an E2-releasing uterine stent, which could improve the efficiency of E2 therapy and be utilized for IUA prevention.

Methods

We designed a silicone rubber stent, which could be implanted in the uterine cavity and continuously release E2 in long term. Stents were placed in rodent uterine, and removed at different time points. Remaining E2 in stent was measured by high performance liquid chromatography (HPLC), and organ E2 concentrations were detected by enzyme-linked immuno sorbent assay (ELISA). Endometrium morphology was examined by histological staining of paraffin sections.

Results

Our stent showed a controlled release of E2 in rodent uterine for over 60 days, and significantly increased E2 concentration in serum and in situ uterine. After the stent was removed from uterine, E2 rapidly reverted to a normal level. Also, the stent did not induce pathological changes in endometrium.

Conclusions

The uterine stent provided abundant local E2 in uterine cavity with satisfactory safety. The silicone rubber based E2-releasing uterine stent could be further advanced by adjusting its shape and E2 load for its clinical application, and might promisingly help lowering the incidence of IUA.

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The silicone rubber uterine stent continuously released E2 in long term.

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The E2-releasing uterine stent revealed more efficient E2 delivery capacity than orally administrated E2.

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The E2-releasing uterine stent is safe for endometrium and remote organs.

Recent progress of Bioinspired Hydrogel-based delivery system for endometrial repair

Endometrial injury is the main fact leading to infertility. Current treatments of endometrial injury present many problems, such as unable to achieve desired effects due to low retention and the inherent potential risk of injury. Besides, it is important to the development of bioinspired material that can mimic the natural tissue and possess native tissue topography. Hydrogel is a kind of bioinspired superhydrophilic materials with unique characteristics, such as excellent biocompatibility, biodegradability, porosity, swelling, and cross-linkage. These unique physiochemical properties of bioinspired hydrogels enable their promising application as novel delivery platform and alternative therapies for endometrial injury. In this mini review, we summarize the recent advances in bioinispred hydrogel-based delivery system for endometrial repair, including as a post-operative physical barrier and therapeutic delivery system. In addition, present status, limitations, and future perspectives are also discussed.

Estradiol and intrauterine device treatment for moderate and severe intrauterine adhesions after transcervical resection

Objective

To explore the effect of 4 mg/day, 6 mg/day, and 8 mg/day estradiol alone or in combination with an intrauterine device (IUD) in patients with moderate and severe intrauterine adhesion (IUA) after transcervical resection of adhesion (TCRA).

Methods

Patients with moderate or severe IUA who reived 4 mg/day, 6 mg/day, and 8 mg/day estradiol alone or in combination with an intrauterine device (IUD) after TCRA in Women’s Hospital, Zhejiang University School of Medicine, from March 2014 to December 2014 were enrolled in this retrospective case–control study. In group A, 14 patients received estradiol 4 mg/day + IUD after the first operation; in group B, 29 patients (group B0) received estradiol 6 mg/day after the first operation, and 73 patients (group B1) received estradiol 6 mg/day + IUD; in group C, 14 patients received estradiol 8 mg/day + IUD after the first operation. Referring to ESGE's IUA diagnostic classification method, 72 patients had moderate adhesion, and 58 cases had severe adhesion. Outpatient follow-up was performed at 1 and 23 months and after 1 year. The postoperative menstrual improvement, uterine cavity recovery, drug side effects at two to three months, and pregnancy situation at one year were recorded.

Results

There were no significant differences in age, BMI, and previous intrauterine operation times between the 3 groups (all p > 0.05). Compared with Group A, more patients in group C had severe IUA (p = 0.008). In addition, there were no differences in menstrual recovery, uterine cavity recovery, and pregnancy in one year between the 3 groups (p > 0.05) and between groups B₀ and B₁ (p > 0.05). In group B1, 51 (69.86%) patients had IUD incarceration.

Conclusion

This data suggests that 4 mg/d doses of estrogen may have the same effect in improving the menstrual condition, uterine cavity morphology, and reproductive ability compared to a higher dosage (6 mg/day estrogen and 8 mg/day). In addition, the placement of IUD in the uterine cavity during TCRA may cause IUD incarceration, and the treatment results for the prevention of IUA are not better than without IUD.

A review of the effects of estrogen and epithelial-mesenchymal transformation on intrauterine adhesion and endometriosis

Uterus transplantation has become an option for women suffering from some form of infertility. Current review discusses key physiological functions of the endometrium requiring the transition of tissue cells between the mesenchyme and epithelial cell phenotype, a process known as epithelial-mesenchymal transition (EMT). Estrogen and EMT play a key role in the pathogenesis and treatment of intrauterine adhesion and endometriosis. There is also a close regulatory relationship between estrogen and EMT, and investigation of this relationship is of great significance for the treatment of endometrial disorders. The present review discusses the effects of estrogen on endometrial dysfunction, with a focus on the relationship between estrogen and EMT in endometrial disorders, taking into consideration the mechanisms by which receptors that regulate their functions and proteins that regulate their local biological functions interact with the factors involved in EMT. In addition, the review summarizes emerging drugs targeting receptors or proteins and provides information on the direction of new therapies for endometrial disorders.

Co-Culture of Bone Marrow Mesenchymal Stem Cells Regulates the Fibrotic Response of Endometrial Stromal Cells

This study explored the protective effects and mechanisms of bone marrow mesenchymal stem cells (BMSCs) on the fibrotic response of endometrial stromal cells. The endometrial cells were isolated from intrauterine adhesions (IUA) patients and assigned into control group, TGF-β1 group, BMSC group which was co-cultured with BMSCs in presence of TGF-β1; Exo group (treated with BMSCs-originated exosomes); Exo-inhibitor group (treated with exosome-specific inhibitors) followed by analysis of α-SMA and Vimentin level, cell viability and expression of TGFBR2, TGFβ-1, Fibronectin (FN), α-SMA, Collagen 1α1 (Col1a1), Smad2/3 and p-Smad2/3. After TGF-β1 treatment, cells exhibited higher expression of p-Smad2/3, TGFBR2, FN, TGF-SMA and COL1A1 along with reduced cell proliferation. However, BMSCs-originated exosomes or co-culture with BMSCs reversed these changes which could be inverted by exosome-specific inhibitors. In conclusion, BMSCs-originated exosomes and BMSCs exerted an anti-fibrosis effect, which was possibly through regulation of TGFβ1/Smad2/Smad3 signalling pathway in endometrial stromal cells.

Comparison of the Reproductive Outcome Between 2 and 4 mg Daily Doses of Estradiol After Hysteroscopic Adhesiolysis: A Propensity Score Matching Analysis-Retrospective Cohort Study

OBJECTIVE

To investigate the effect of two postoperative doses of estradiol valerate (2 and 4 mg/day) on reproductive outcomes in patients with moderate to severe intrauterine adhesions (IUAs).

METHODS

A retrospective cohort study was conducted at a single tertiary reproductive medical center between January 2018 and December 2019 to compare the reproductive outcomes of two doses of estradiol valerate (2 and 4 mg daily) after hysteroscopic adhesiolysis. All patients received adjuvant postoperative treatment with a Foley catheter, hyaluronic acid gel, and medication therapy. Hysteroscopy was repeated every 7 days after surgery. Multivariate regression analysis and propensity score matching (PSM) were performed to minimize intrinsic bias.

RESULTS

A total of 212 patients with moderate to severe IUAs were included: 74 patients received 2 mg of estradiol valerate daily and 138 patients received 4 mg of estradiol daily postoperatively. No significant differences were found in the reproductive outcomes between the two groups, including clinical pregnancy rates. The multivariable regression analyses both before and after PSM also showed that there was no significant difference in the menstrual improvement and clinical pregnancy rates between the two groups.

CONCLUSIONS

We suggest the use of a lower dose (2 mg/day) of estradiol valerate as an adjuvant therapy for IUAs to minimize estrogen-related side effects.

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.

The glucagon-like peptide-1 (GLP-1) analog exenatide ameliorates intrauterine adhesions in mice

OBJECTIVE

The purpose of the experiments in this study was to explore the effect of exenatide on intrauterine adhesions (IUAs) and to elucidate its mechanism to provide new ideas for the clinical treatment of IUAs.

METHODS

In this study, an animal model of IUAs was established by double stimulation using mechanical curettage and inflammation. After modeling, the treatment group was injected subcutaneously with three doses of exenatide for two weeks. The model group was injected with sterile ultrapure water, and the sham operation group was treated the same as the normal group, except for the observation of abdominal wound changes. Two weeks later, all mice were sacrificed by cervical dysfunction. The obtained mouse uterine tissue was used for subsequent experimental detection, using HE and Masson staining for histomorphological and pathological analysis; qRT-PCR for the detection of TGF-β1, α-SMA, and MMP-9 gene expression in uterine tissue; and western blotting analysis of TGF-β1, α-SMA, and collagen 1 protein expression to verify whether exenatide has a therapeutic effect on IUAs in mice.

RESULTS

In the high-dose exenatide treatment group, the endometrial glands significantly increased in size, and the deposition area of collagen fibers in the endometrial tissue was significantly reduced. We observed that the mRNA expression of TGF-β1 and α-SMA in the endometrial tissue of IUAs mice in this group was significantly reduced, while the expression of MMP-9 was significantly increased. In addition, we found that the protein expression of TGF-β1, α-SMA, and collagen 1 remarkably decreased after treatment with exenatide.

CONCLUSION

Exenatide may reduce the deposition of collagen fibers in the uterus of IUAs mice and promote the proliferation of endometrial glands in mice.

Metabolomics Analysis Discovers Estrogen Altering Cell Proliferation via the Pentose Phosphate Pathway in Infertility Patient Endometria

Estrogen therapy is widely used as a supplementary treatment after hysteroscopy for female infertility patients owing to its protective function that improves endometrial regeneration and menstruation, inhibits recurrent adhesions, and improves subsequent conception rate. The endometrial protective function of such estrogen administration pre-surgery is still controversial. In the current study, 12 infertility patients were enrolled, who were treated with estrogen before hysteroscopy surgery. Using cutting-edge metabolomic analysis, we observed alterations in the pentose phosphate pathway (PPP) intermediates of the patient's endometrial tissues. Furthermore, using Ishikawa endometrial cells, we validated our clinical discovery and identified estrogen-ESR-G6PD-PPP axial function, which promotes estrogen-induced cell proliferation.

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.

Estrogen attenuates TGF-β1-induced EMT in intrauterine adhesion by activating Wnt/β-catenin signaling pathway

Although estrogen has crucial functions for endometrium growth, the specific dose and underlying molecular mechanism in intrauterine adhesion (IUA) remain unclear. In this study, we aimed to investigate the effects of estrogen on epithelial-mesenchymal transition (EMT) in normal and fibrotic endometrium, and the role of estrogen and Wnt/β-catenin signaling in the formation of endometrial fibrosis. CCK-8 and immunofluorescence assay were performed to access the proliferation of different concentrations of estrogen on normal human endometrial epithelial cells (hEECs). qRT-PCR and western blot assay were utilized to explore the effect of estrogen on EMT in normal and fibrotic endometrium, and main components of Wnt/β-catenin signaling pathway in vitro. Hematoxylin and eosin and Masson staining were used to evaluate the effect of estrogen on endometrial morphology and fibrosis in vivo. Our results indicated that the proliferation of normal hEECs was inhibited by estrogen at a concentration of 30 nM accompanied by upregulation of mesenchymal markers and downregulation of epithelial markers. Interestingly, in the model of transforming growth factor β1 (TGF-β1)-induced endometrial fibrosis, the same concentration of estrogen inhibited the process of EMT, which might be partially mediated by regulation of the Wnt/β-catenin pathway. In addition, relatively high doses of estrogen efficiently increased the number of endometrial glands and reduced the area of fibrosis as determined by the reduction of EMT in IUA animal models. Taken together, our results demonstrated that an appropriate concentration of estrogen may prevent the occurrence and development of IUA by inhibiting the TGF-β1-induced EMT and activating the Wnt/β-catenin pathway.

Transforming growth factor-β1 in intrauterine adhesion

Intrauterine adhesion (IUA), led by trauma to the basal layer, can prevent the endometrium from growing, resulting in complications in females, such as infertility and amenorrhea. Transforming growth factor-β1 (TGF-β1) plays a crucial role in inducing and promoting the differentiation and proliferation of mesenchymal cells, in the secretion of extracellular matrix-associated components, and is a major cytokine in initiating and terminating tissue repair downstream of the TGF-β/Smad signaling pathway. Some evidence supports that TGF-β1 is closely associated with the occurrence and development of IUA, and is regarded as an early risk factor of disease recurrence. Furthermore, the role of TGF-β1 has been demonstrated to be potentially regulated by a variety of cytokines, hormones, enzymes, and microRNAs. This review provides an overview of the expression, function, and regulation of TGF-β1 in IUA, with a brief discussion and perspectives on its future clinical implications on the diagnosis and treatment of IUA.

A prospective randomized controlled trial comparing two different treatments of intrauterine adhesions

RESEARCH QUESTION

Intrauterine adhesions (IUA) are primarily caused by trauma to the endometrium, and hysteroscopy is presently the main treatment for IUA. However, high rates of post-operative adhesion re-formation remain a problem. In this study, the combination of an intrauterine device (IUD) with a Foley catheter and the balloon uterine stent were investigated to evaluate their efficacy in preventing adhesion re-formation and the subsequent reproductive outcomes in patients with moderate to severe adhesions.

DESIGN

A prospective randomized controlled study was conducted in a university-affiliated hospital. A total of 171 women with Asherman's syndrome were initially recruited between August 2016 and December 2017 and were randomized to undergo either balloon uterine stent insertion or placement of a contraceptive IUD plus a Foley catheter after hysteroscopic adhesiolysis. Reduction of adhesion scores, incidence of adhesion re-formation, changes in menstrual flow and reproductive outcomes were analysed.

RESULTS

A total of 118 participants were eligible for analysis. The American Fertility Society (AFS) scores were not significantly different between groups before hysteroscopic adhesiolysis. At the second-look hysteroscopy, the AFS scores and adhesion recurrence rates were significantly higher in the balloon uterine stent group compared with the combination group (P < 0.01 and P = 0.024, respectively). There were no statistically significant differences in pregnancy and live birth rates between the two groups.

CONCLUSIONS

The combination of an IUD and a Foley balloon catheter had better efficacy in preventing adhesion re-formation than the balloon uterine stent alone; however, it did not produce better reproductive outcomes.

Meta-analysis on the use of hyaluronic acid gel to prevent recurrence of intrauterine adhesion after hysteroscopic adhesiolysis

Intrauterine adhesion is a severe complication after intrauterine operation, Various adjuvant therapies failed to improve clinical symptoms and pregnancy rates among patients with moderate-to-severe intrauterine adhesion. At present, hyaluronic acid gel is widely used in the primary prevention of adhesion after hysteroscopic adhesiolysis. However, its efficacy is still under debate. Therefore, the aim of this study was to systematically evaluate the efficacy of hyaluronic acid gel in preventing the recurrence of intrauterine adhesion after hysteroscopic adhesiolysis. The Cochrane Library, Embase, and PubMed databases were used to search for articles published before July 31, 2018, using the following terms: hyaluronic acid, intrauterine adhesions, Asherman's syndrome, IUA, hysteroscopy, and hysteroscopic adhesiolysis. Studies on therapies after hysteroscopic adhesiolysis were collected. The recurrence rate of and pregnancy rate in the presence of intrauterine adhesion after hysteroscopic adhesiolysis were analyzed by RevMan 5.3 software. A total of 6 articles were selected, which included 394 patients who were subjected to hysteroscopic adhesiolysis. The meta-analysis results showed that (1) no statistically significant difference was found between hyaluronic acid gel use and without its use on the score of intrauterine adhesion after hysteroscopic adhesiolysis [the mean difference (MD) = -0.89, 95% confidence interval (CI) (-2.53-0.76), P = 0.29], neither a statistically significant difference was observed between the same groups on the recurrence rate of intrauterine adhesion [odds ratio (OR) = 0.75, 95% CI (0.31-1.81), P = 0.53]; (2) subgroup analysis showed that hyaluronic acid gel could reduce the rate of intrauterine adhesion recurrence in randomized controlled trials [OR = -0.28, 95% CI (0.14-0.56), P = 0.0006]. However, the recurrence rate of intrauterine adhesion after the use of hyaluronic acid gel was not statistically significant in non-randomized controlled experiments [OR = 1.53, 95% CI (0.79-2.95), P = 0.21]; (3) hyaluronic acid gel did not result in a significant effect on pregnancy rate after intrauterine adhesion separation [OR = 2.02, 95% CI (0.53-7.66), P = 0.3]. In conclusion, hyaluronic acid gel could reduce the recurrence rate of intrauterine adhesion, but had no significant effect on the postoperative pregnancy rate.

A Network Meta-Analysis of Efficacy of Different Interventions in the Prevention of Postoperative Intrauterine Adhesions

This network meta‐analysis was conducted to compare the efficacy of six interventions, including anti‐blocking agents, intrauterine contraceptive devices (IUDs), estrogens, intrauterine balloon, Foley catheter, and amnion graft for the prevention of intrauterine adhesions (IUAs). We searched PubMed, Embase, and Cochrane Library from inception to December 2016. Cohort studies meeting these six interventions in the prevention of IUAs were included. The combination of direct and indirect evidence was conducted to assess the odds ratio (OR) or weighted mean differences and surface under the cumulative ranking curves of the six interventions in the prevention of postoperative IUAs. Finally, 12 eligible cohort studies were included in this network meta‐analysis. The results of this network meta‐analysis demonstrated that during 1 to 2 months after operation, compared with the surgical group, anti‐blocking agent, and estrogens presented with relatively low ratios of postoperative IUAs (OR = 0.30 95% confidence interval (CI) = 0.10–0.67; OR = 0.12, 95% CI = 0.01–0.78, respectively). Compared with IUDs, estrogens exerted comparatively low ratio of postoperative IUAs (OR = 0.10, 95% CI = 0.01–0.90), which indicated that anti‐blocking agent and estrogens had relatively better prevention efficacy. The cluster analysis showed that estrogens had relatively better efficacy in the prevention postoperative IUAs. Overall, our findings support that estrogens had relatively better efficacy in the prevention of postoperative IUAs.

Supplements to Conventional Treatment After Hysteroscopic Lysis of Intrauterine Adhesions: A Systematic Review

Intrauterine adhesions (IUAs) are a result of trauma to the basalis layer of the endometrium and may lead to clinical sequelae such as miscarriage, infertility, and menstrual irregularities. Hysteroscopy is recognized as the gold standard in diagnosis and management, although the optimal treatment after surgical intervention remains unclear. This review aimed to provide an update on the treatment options available after hysteroscopic adhesiolysis and to facilitate clinical management of patients with IUAs. To avoid duplicating previous work, the review focused on studies that compared various adjunctive postoperative treatments in patients receiving hormone therapy. Of 548 studies, 15 papers fit our criteria that compared post-resection treatment options in women with IUAs. Meta-analysis of the use of Foley catheter or amnion graft as an adjunctive therapy after adhesiolysis failed to show a statistical difference (odds ratio 1.55; 95% confidence interval 0.60-3.99). Meta-analysis could not be done for the 13 remaining studies as a result of extensive heterogeneity, bias, or non-comparable end points. The lack of a universal classification system for IUAs and the use of variable outcomes to measure the success of adjunctive treatment pose challenges in generating standard treatment recommendations. This review calls for the development of a universal classification system and studies with consistent parameters and end points to allow for the generation of standard treatment guidelines. On the basis of the available evidence, recommendation of specific adjunctive treatments after hysteroscopic adhesiolysis is unjustified.

Therapeutic options and drug delivery strategies for the prevention of intrauterine adhesions

Intrauterine adhesions (IUAs) are bands of fibrous tissue that form in the endometrial cavity and associated with the increased risk of abnormal menstruation, recurrent pregnancy loss, secondary infertility, and pregnancy complications. Physical barriers, including intrauterine device and hydrogel, were clinical available to prevent the post-operational IUAs. But physically separation of the injured endometrium relies on the own limited healing power and often ends with recurrence. In recent years, the mechanisms driving IUAs treatment has validated the application of hormones, and further stem cell therapy has also led to the development of novel therapeutic agents with promising efficacy in pre-clinical and initial clinical studies. Still, it is challenging to delivery the therpaeutic factors to the injured uterus. Herein, in this review, we discuss the traditional intervention methods for the prevention of IUAs, as well as novel therapeutics and delivery strategies that will most likely change the treatment paradigms for better clinical outcomes. The combination strategy that using physical barriers as the delivery carriers for therapeutics might provide new alternatives for the prevention of IUAs.

Using 17β-estradiol heparin-poloxamer thermosensitive hydrogel to enhance the endometrial regeneration and functional recovery of intrauterine adhesions in a rat model

Mechanical damage or infection to the endometrium can lead to the formation of adhesions in the uterine cavity, which may result in reduced reproductive outcome and/or pregnancy complications. The prognosis of this disease is poor due to few effective treatments and the complex environment of endometrium. Heparin-Poloxamer Hydrogel (HP hydrogel) is a nontoxic and biodegradable biomaterial, which has been commonly used as a sustained-release delivery system. In this study, we applied a mini-endometrial curette to scrape the endometrium of rats to mimic the process of curettage in patients. After the establishment of IUA model in rats, we injected the thermo-sensitive hydrogel(E₂-HP hydrogel) into the injured uterine cavity and evaluated the therapeutic effect of E₂-HP hydrogel on the recovery of IUA. Our results showed that E₂-HP hydrogel can significantly facilitate the regeneration of injured endometrium along with inhibiting the cell apoptosis in IUA model. Furthermore, we revealed that E₂-HP hydrogel on the recovery of IUA was closely associated with the upregulation of kisspeptin through activating the ERK1/2 and MAPKs p38 pathways. In conclusion, E₂-HP hydrogel can effectively transfer E₂ into the injured endometrium and it can be considered as a promising therapeutic method for the women with intrauterine adhesions.

Estrogen therapy before hysteroscopic adhesiolysis improves the fertility outcome in patients with intrauterine adhesions

PURPOSES

To describe the fertility outcomes after hysteroscopic adhesiolysis combined with preoperative hormone treatment in women with intrauterine adhesion (IUA).

METHODS

This study is a retrospective cohort study. A total of 230 patients with IUA underwent hysteroscopic adhesiolysis combined with hormone treatment from Jan 2012 to Jun 2018. 148 patients who received preoperative estrogen treatment were enrolled into group A and 82 patients without preoperative estrogen treatment were enrolled into group B. All the patients underwent hysteroscopic adhesiolysis and received postoperative estrogen therapy, intrauterine indwelling device. Second or third look was performed after 2-3 months.

RESULTS

90.87% (209/230) patients complete the study. The AFS scores at baseline were higher in the group A than group B. After the preoperative E2 treatment, group A achieved the comparable AFS score to group B before the surgery. The cumulative fertility rate in group A was comparable in group B, both in the ITT analysis (49.32% vs. 52.44%, p = 0.651) and the PP analysis (54.07% vs.58.10%, p = 0.575).The mean conception time was also similar in group A and group B (8.30 ± 6.47 vs. 8.54 ± 5.68 months, p = 0.837). Besides, the surgery times in group A were less than group B. There was no difference in the rate of adverse events between two groups.

CONCLUSIONS

Hysteroscopic adhesiolysis combined with preoperative oestrogen could reduce the preoperative AFS scores and the times of surgery which yield a similar conception rate in women with less severe intrauterine adhesions.

Hysteroscopy for treating subfertility associated with suspected major uterine cavity abnormalities

BACKGROUND

Observational studies suggest higher pregnancy rates after the hysteroscopic removal of endometrial polyps, submucous fibroids, uterine septum or intrauterine adhesions, which are present in 10% to 15% of women seeking treatment for subfertility.

OBJECTIVES

To assess the effects of the hysteroscopic removal of endometrial polyps, submucous fibroids, uterine septum or intrauterine adhesions suspected on ultrasound, hysterosalpingography, diagnostic hysteroscopy or any combination of these methods in women with otherwise unexplained subfertility or prior to intrauterine insemination (IUI), in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI).

SEARCH METHODS

We searched the following databases from their inception to 16 April 2018; The Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Studies Online, ; MEDLINE, Embase , CINAHL , and other electronic sources of trials including trial registers, sources of unpublished literature, and reference lists. We handsearched the American Society for Reproductive Medicine (ASRM) conference abstracts and proceedings (from 1 January 2014 to 12 May 2018) and we contacted experts in the field.

SELECTION CRITERIA

Randomised comparison between operative hysteroscopy versus control for unexplained subfertility associated with suspected major uterine cavity abnormalities.Randomised comparison between operative hysteroscopy versus control for suspected major uterine cavity abnormalities prior to medically assisted reproduction.Primary outcomes were live birth and hysteroscopy complications. Secondary outcomes were pregnancy and miscarriage.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and risk of bias, and extracted data. We contacted study authors for additional information.

MAIN RESULTS

Two studies met the inclusion criteria.1. Randomised comparison between operative hysteroscopy versus control for unexplained subfertility associated with suspected major uterine cavity abnormalities.In women with otherwise unexplained subfertility and submucous fibroids, we were uncertain whether hysteroscopic myomectomy improved the clinical pregnancy rate compared to expectant management (odds ratio (OR) 2.44, 95% confidence interval (CI) 0.97 to 6.17; P = 0.06, 94 women; very low-quality evidence). We are uncertain whether hysteroscopic myomectomy improves the miscarriage rate compared to expectant management (OR 1.54, 95% CI 0.47 to 5.00; P = 0.47, 94 women; very low-quality evidence). We found no data on live birth or hysteroscopy complication rates. We found no studies in women with endometrial polyps, intrauterine adhesions or uterine septum for this randomised comparison.2. Randomised comparison between operative hysteroscopy versus control for suspected major uterine cavity abnormalities prior to medically assisted reproduction.The hysteroscopic removal of polyps prior to IUI may have improved the clinical pregnancy rate compared to diagnostic hysteroscopy only: if 28% of women achieved a clinical pregnancy without polyp removal, the evidence suggested that 63% of women (95% CI 45% to 89%) achieved a clinical pregnancy after the hysteroscopic removal of the endometrial polyps (OR 4.41, 95% CI 2.45 to 7.96; P < 0.00001, 204 women; low-quality evidence). We found no data on live birth, hysteroscopy complication or miscarriage rates in women with endometrial polyps prior to IUI. We found no studies in women with submucous fibroids, intrauterine adhesions or uterine septum prior to IUI or in women with all types of suspected uterine cavity abnormalities prior to IVF/ICSI.

AUTHORS' CONCLUSIONS

Uncertainty remains concerning an important benefit with the hysteroscopic removal of submucous fibroids for improving the clinical pregnancy rates in women with otherwise unexplained subfertility. The available low-quality evidence suggests that the hysteroscopic removal of endometrial polyps suspected on ultrasound in women prior to IUI may improve the clinical pregnancy rate compared to simple diagnostic hysteroscopy. More research is needed to measure the effectiveness of the hysteroscopic treatment of suspected major uterine cavity abnormalities in women with unexplained subfertility or prior to IUI, IVF or ICSI.

A cohort study comparing 4 mg and 10 mg daily doses of postoperative oestradiol therapy to prevent adhesion reformation after hysteroscopic adhesiolysis

This is a retrospective cohort study conducted in a national training centre for hysteroscopy between January 2012 and December 2014 to compare the clinical outcome of two doses of oestradiol valerate (4 mg and 10 mg daily) in the prevention of recurrence of adhesions after hysteroscopic adhesiolysis. A total of 176 women who suffered from Asherman syndrome with moderate to severe intrauterine adhesions were included: 91 subjects received a 10 mg daily dose of oestradiol and 85 subjects received a 4 mg daily dose of oestradiol in the postoperative period. Second look hysteroscopy was performed 4-6 weeks after the initial surgery. There was no difference in age and preoperative American Fertility Society (AFS) adhesion score between the two groups. The proportion of women in whom menstruation had returned to normal in the 10 mg group (49/91 = 53.8%) was significantly (p < 0.05) higher than that of subjects in the 4 mg group (35/85 = 41.2%). However, there was no difference in AFS scores at second look hysteroscopy between the two groups or in the conception rate and miscarriage rate between the two groups. The findings do not support the use of high-dose postoperative oestrogen therapy following hysteroscopic adhesiolysis.

The different dosages of estrogen affect endometrial fibrosis and receptivity, but not SDF-1/CXCR4 axis in the treatment of intrauterine adhesions

OBJECTIVE

The study was to evaluate whether fibrotic markers, endometrial receptivity markers and SDF-1/CXCR4 had been changed in the treatment of intrauterine adhesions (IUAs) by different dosages of estrogen.

STUDY DESIGN

A total of 39 patients with IUAs were treated with EV 4 mg or 9 mg randomly post-surgery. TGF-β1/MMP-9, VEGF/αvβ3 and SDF-1/CXCR4 were detected in endometrial tissue before and after treatment by real-time PCR and Western blot.

RESULTS

TGF-β1 and MMP-9 expression significantly decreased after treatment for 3 months than before (p < .05), the falling range was larger with EV 4 mg than 9 mg in the mild-moderate degree IUAs (p < .05); Integrin avβ3 expression significantly increased after treatment for 3 months than before (p < .05), the variation range was larger with EV 4 mg than 9 mg (p < .05); CXCR4 expression had no significant change after treatment 3 months compared to that before treatment (p > .05). SDF-1 presented an upward tendency at early phase, and it came back to the level of pre-surgery. But there were no significant difference between treatment with 4 mg and 9 mg in the rate of menstrual restoration and pregnancy follow-up 3 months after the treatment.

CONCLUSIONS

Endometrium fibrosis may be inhibited and endometrium receptivity may be improved by estrogen with moderate dosage therapy. Compared to the large one, it seems to be advantageous.

Anti-adhesion therapy following operative hysteroscopy for treatment of female subfertility

BACKGROUND

Observational evidence suggests a potential benefit with several anti-adhesion therapies in women undergoing operative hysteroscopy (e.g. insertion of an intrauterine device or balloon, hormonal treatment, barrier gels or human amniotic membrane grafting) for decreasing intrauterine adhesions (IUAs).

OBJECTIVES

To assess the effectiveness of anti-adhesion therapies versus placebo, no treatment or any other anti-adhesion therapy, following operative hysteroscopy for treatment of female subfertility.

SEARCH METHODS

We searched the following databases from inception to June 2017: the Cochrane Gynaecology and Fertility Group Specialised Register; the Cochrane Central Register of Studies (CRSO); MEDLINE; Embase; CINAHL and other electronic sources of trials, including trial registers, sources of unpublished literature and reference lists. We handsearched the Journal of Minimally Invasive Gynecology, and we contacted experts in the field. We also searched reference lists of appropriate papers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of anti-adhesion therapies versus placebo, no treatment or any other anti-adhesion therapy following operative hysteroscopy in subfertile women. The primary outcome was live birth. Secondary outcomes were clinical pregnancy, miscarriage and IUAs present at second-look hysteroscopy, along with mean adhesion scores and severity of IUAs.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, extracted data and evaluated quality of evidence using the GRADE method.

MAIN RESULTS

The overall quality of the evidence was low to very low. The main limitations were serious risk of bias related to blinding of participants and personnel, indirectness and imprecision. We identified 16 RCTs comparing a device versus no treatment (two studies; 90 women), hormonal treatment versus no treatment or placebo (two studies; 136 women), device combined with hormonal treatment versus no treatment (one study; 20 women), barrier gel versus no treatment (five studies; 464 women), device with graft versus device without graft (three studies; 190 women), one type of device versus another device (one study; 201 women), gel combined with hormonal treatment and antibiotics versus hormonal treatment with antibiotics (one study; 52 women) and device combined with gel versus device (one study; 120 women). The total number of participants was 1273, but data on 1133 women were available for analysis. Only two of 16 studies included 100% infertile women; in all other studies, the proportion was variable or unknown.No study reported live birth, but some (five studies) reported outcomes that were used as surrogate outcomes for live birth (term delivery or ongoing pregnancy). Anti-adhesion therapy versus placebo or no treatment following operative hysteroscopy.There was insufficient evidence to determine whether there was a difference between the use of a device or hormonal treatment compared to no treatment or placebo with respect to term delivery or ongoing pregnancy rates (odds ratio (OR) 0.94, 95% confidence interval (CI) 0.42 to 2.12; 107 women; 2 studies; I² = 0%; very-low-quality evidence).There were fewer IUAs at second-look hysteroscopy using a device with or without hormonal treatment or hormonal treatment or barrier gels compared with no treatment or placebo (OR 0.35, 95% CI 0.21 to 0.60; 560 women; 8 studies; I² = 0%; low-quality evidence). The number needed to treat for an additional beneficial outcome (NNTB) was 9 (95% CI 5 to 17). Comparisons of different anti-adhesion therapies following operative hysteroscopyIt was unclear whether there was a difference between the use of a device combined with graft versus device only for the outcome of ongoing pregnancy (OR 1.48, 95% CI 0.57 to 3.83; 180 women; 3 studies; I² = 0%; low-quality evidence). There were fewer IUAs at second-look hysteroscopy using a device with or without graft/gel or gel combined with hormonal treatment and antibiotics compared with using a device only or hormonal treatment combined with antibiotics, but the findings of this meta-analysis were affected by evidence quality (OR 0.55, 95% CI 0.36 to 0.83; 451 women; 5 studies; I² = 0%; low-quality evidence).

AUTHORS' CONCLUSIONS

Implications for clinical practiceThe quality of the evidence ranged from very low to low. The effectiveness of anti-adhesion treatment for improving key reproductive outcomes or for decreasing IUAs following operative hysteroscopy in subfertile women remains uncertain. Implications for researchMore research is needed to assess the comparative safety and (cost-)effectiveness of different anti-adhesion treatments compared to no treatment or other interventions for improving key reproductive outcomes in subfertile women.

The Effect of Adjuvant Treatment to Prevent and Treat Intrauterine Adhesions: A Network Meta-Analysis of Randomized Controlled Trials

Intrauterine adhesions (IUAs) can lead to partial or complete closure of the uterine cavity, which may result in symptoms including abnormal menstruation, infertility, and pelvic pain. A network meta-analysis was performed to assess the effect of adjuvant therapy on the prevention and treatment of IUAs. We searched electronic databases, including PubMed, Embase, and the Cochrane Library, up to May 5, 2017, without language restrictions. The primary outcomes in the present analysis were the rate of IUAs for prevention and the rate of IUA recurrence for treatment. The secondary outcomes included the IUA score and the rate of severity of IUAs. The treatments were then ranked by the surface under the cumulative ranking curve (SUCRA). We included 20 articles that involved a total of 1891 patients in our analysis. In the outcomes of prevention-related studies, an alginate hyaluronate-carboxymethylcellulose membrane (ACH) (n = 10, SUCRA score = 93.3%) was the adjuvant treatment that most effectively reduced IUA incidence. It was followed by intercoat (n = 10, SUCRA score = 74.7%) and misoprostol (n = 10, SUCRA score = 68.6%). In addition, auto-cross-linked hyaluronic acid (ACP) (n = 3, SUCRA score = 83.2%) and intercoat (n = 3, SUCRA score = 66.4%) each corresponded to a relatively high preventive effect against severe IUAs. In the treatment-related studies, ACP plus a balloon (n = 4, SUCRA score = 96.3%) and a freeze-dried amnion graft plus a balloon (n = 4, SUCRA score = 62.7%) most effectively reduced IUA recurrence and had a high probability of most effectively reducing IUA scores. Therefore, according to the prophylactic analysis, ACH and intercoat were most likely to prevent IUA development. In our analysis of agents used to prevent severe IUAs, we found that ACP and intercoat provided significant advantages and had high reliability. In our analysis of treatments, ACP plus a balloon and freeze-dried amniotic agents plus a balloon were most likely to reduce IUA recurrence and IUA scores after adhesiolysis.

Three-dimensional structure micelles of heparin-poloxamer improve the therapeutic effect of 17β-estradiol on endometrial regeneration for intrauterine adhesions in a rat model

Intrauterine adhesions (IUA) frequently occur after infectious or mechanical injury to the endometrium, which may lead to infertility and/or pregnancy complications. There are few effective treatments due to the complex function of endometrium and shortage of native materials. 17β-estradiol (E₂) is commonly used as an ancillary treatment in IUA patients, but it is limited by its poor solubility in aqueous solutions and low concentrations at the injured sites. In this research, a mini-endometrial curette was used to injure the rat’s endometrium to form an IUA model. 17β-estradiol was encapsulated into the micelles of heparin-poloxamer and a thermosensitive hydrogel (E₂-HP hydrogel) was formed. This sustained releasing system was applied to restore the structure and function of the injured uterus. E₂-HP hydrogel was constructed and relevant characteristics including gelation temperature and micromorphology were evaluated. Sustained release of 17β-estradiol from HP hydrogel was performed both in vitro and in vivo. Ultrasonography measurement and pathologic characteristics on the IUA rats were performed to evaluate the therapeutic effect of E₂-HP hydrogel. Endoplasmic reticulum (ER) stress-related apoptosis was analyzed to explore the possible mechanisms in IUA recovery. E₂-HP hydrogel showed a prolonged release of E₂ at the targeting region and more effective endometrium regeneration in IUA rats. Significant improvements in both gland numbers and fibrosis area were observed in the E₂-HP hydrogel group. We also demonstrated that E₂-HP hydrogel in the recovery of IUA was closely related to the suppression of ER stress signals via the activation of downstream signals, PI3K/Akt and ERK1/2. HP hydrogel might be an effective approach to deliver E₂ into the injured endometrium. Therapeutic strategies targeting ER stress using E₂-HP hydrogel might be a promising solution for the treatment of women with intrauterine adhesions.