A prospective, randomized, controlled trial comparing two doses of oestrogen therapy after hysteroscopic adhesiolysis to prevent intrauterine adhesion recurrence

Evolution of biotechnological advances and regenerative therapies for endometrial disorders: a systematic review

BACKGROUND

The establishment and maintenance of pregnancy depend on endometrial competence. Asherman syndrome (AS) and intrauterine adhesions (IUA), or endometrial atrophy (EA) and thin endometrium (TE), can either originate autonomously or arise as a result from conditions (i.e. endometritis or congenital hypoplasia), or medical interventions (e.g. surgeries, hormonal therapies, uterine curettage or radiotherapy). Affected patients may present an altered or inadequate endometrial lining that hinders embryo implantation and increases the risk of poor pregnancy outcomes and miscarriage. In humans, AS/IUA and EA/TE are mainly treated with surgeries or pharmacotherapy, however the reported efficacy of these therapeutic approaches remains unclear. Thus, novel regenerative techniques utilizing stem cells, growth factors, or tissue engineering have emerged to improve reproductive outcomes.

OBJECTIVE AND RATIONALE

This review comprehensively summarizes the methodologies and outcomes of emerging biotechnologies (cellular, acellular, and bioengineering approaches) to treat human endometrial pathologies. Regenerative therapies derived from human tissues or blood which were studied in preclinical models (in vitro and in vivo) and clinical trials are discussed.

SEARCH METHODS

A systematic search of full-text articles available in PubMed and Embase was conducted to identify original peer-reviewed studies published in English between January 2000 and September 2023. The search terms included: human, uterus, endometrium, Asherman syndrome, intrauterine adhesions, endometrial atrophy, thin endometrium, endometritis, congenital hypoplasia, curettage, radiotherapy, regenerative therapy, bioengineering, stem cells, vesicles, platelet-rich plasma, biomaterials, microfluidic, bioprinting, organoids, hydrogel, scaffold, sheet, miRNA, sildenafil, nitroglycerine, aspirin, growth hormone, progesterone, and estrogen. Preclinical and clinical studies on cellular, acellular, and bioengineering strategies to repair or regenerate the human endometrium were included. Additional studies were identified through manual searches.

OUTCOMES

From a total of 4366 records identified, 164 studies (3.8%) were included for systematic review. Due to heterogeneity in the study design and measured outcome parameters in both preclinical and clinical studies, the findings were evaluated qualitatively and quantitatively without meta-analysis. Groups using stem cell-based treatments for endometrial pathologies commonly employed mesenchymal stem cells (MSCs) derived from the human bone marrow or umbilical cord. Alternatively, acellular therapies based on platelet-rich plasma (PRP) or extracellular vesicles are gaining popularity. These are accompanied by the emergence of bioengineering strategies based on extracellular matrix (ECM)-derived hydrogels or synthetic biosimilars that sustain local delivery of cells and growth factors, reporting promising results. Combined therapies that target multiple aspects of tissue repair and regeneration remain in preclinical testing but have shown translational value. This review highlights the myriad of therapeutic material sources, administration methods, and carriers that have been tested.

WIDER IMPLICATIONS

Therapies that promote endometrial proliferation, vascular development, and tissue repair may help restore endometrial function and, ultimately, fertility. Based on the existing evidence, cost, accessibility, and availability of the therapies, we propose the development of triple-hit regenerative strategies, potentially combining high-yield MSCs (e.g. from bone marrow or umbilical cord) with acellular treatments (PRP), possibly integrated in ECM hydrogels. Advances in biotechnologies together with insights from preclinical models will pave the way for developing personalized treatment regimens for patients with infertility-causing endometrial disorders such as AS/IUA, EA/TE, and endometritis.

REGISTRATION NUMBER

https://osf.io/th8yf/.

Early GnRH-agonist therapy does not negatively impact the endometrial repair process or live birth rate

Study objective

To investigate whether different timings of GnRH-a downregulation affected assisted reproductive outcomes in infertile women with moderate-to-severe intrauterine adhesions (IUAs) accompanied by adenomyosis.

Design

A retrospective case series.

Setting

An assisted reproductive technology center.

Patients

The study reviewed 123 infertile women with moderate-to-severe IUAs accompanied by adenomyosis undergoing their first frozen-thawed embryo transfer (FET) cycles between January 2019 and December 2021.

Measurements and main results

The majority of patients had moderate IUA (n=116, 94.31%). The average Basal uterine volume was 73.58 ± 36.50 cm3. The mean interval from operation to the first downregulation was 21.07 ± 18.02 days (range, 1-79 days). The mean duration of hormone replacement therapy (HRT) was 16.93 ± 6.29 days. The average endometrial thickness on the day before transfer was 10.83 ± 1.75 mm. A total of 70 women achieved clinical pregnancy (56.91%). Perinatal outcomes included live birth (n=47, 67.14%), early miscarriage (n=18, 25.71%), and late miscarriage (n=5, 7.14%). The time interval between uterine operation and the first downregulation was not a significant variable affecting live birth. Maternal age was the only risk factor associated with live birth (OR:0.89; 95% CI: 0.79-0.99, P=0.041).

Conclusions

The earlier initiation of GnRH-a to suppress adenomyosis prior to endometrial preparation for frozen embryo transfer did not negatively impact repair of the endometrium after resection.

Multilayered Shape-Morphing Scaffolds with a Hierarchical Structure for Uterine Tissue Regeneration

Owing to dysfunction of the uterus, millions of couples around the world suffer from infertility. Different from conventional treatments, tissue engineering provides a new and promising approach to deal with difficult problems such as human tissue or organ failure. Adopting scaffold-based tissue engineering, three-dimensional (3D) porous scaffolds in combination with stem cells and appropriate biomolecules may be constructed for uterine tissue regeneration. In this study, a hierarchical tissue engineering scaffold, which mimicked the uterine tissue structure and functions, was designed, and the biomimicking scaffolds were then successfully fabricated using solvent casting, layer-by-layer assembly, and 3D bioprinting techniques. For the multilayered, hierarchical structured scaffolds, poly(l-lactide-co-trimethylene carbonate) (PLLA-co-TMC, "PLATMC" in short) and poly(lactic acid-co-glycolic acid) (PLGA) blends were first used to fabricate the shape-morphing layer of the scaffolds, which was to mimic the function of myometrium in uterine tissue. The PLATMC/PLGA polymer blend scaffolds were highly stretchable. Subsequently, after etching of the PLATMC/PLGA surface and employing estradiol (E2), polydopamine (PDA), and hyaluronic acid (HA), PDA@E2/HA multilayer films were formed on PLATMC/PLGA scaffolds to build an intelligent delivery platform to enable controlled and sustained release of E2. The PDA@E2/HA multilayer films also improved the biological performance of the scaffold. Finally, a layer of bone marrow-derived mesenchymal stem cell (BMSC)-laden hydrogel [which was a blend of gelatin methacryloyl (GelMA) and gelatin (Gel)] was 3D printed on the PDA@E2/HA multilayer films of the scaffold, thereby completing the construction of the hierarchical scaffold. BMSCs in the GelMA/Gel hydrogel layer exhibited excellent cell viability and could spread and be released eventually upon biodegradation of the GelMA/Gel hydrogel. It was shown that the hierarchically structured scaffolds could evolve from the initial flat shape into the tubular structure completely in an aqueous environment at 37 °C, fulfilling the requirement for curved scaffolds for uterine tissue engineering. The biomimicking scaffolds with a hierarchical structure and curved shape, high stretchability, and controlled and sustained E2 release appear to be very promising for uterine tissue regeneration.

Comparison of Secondary Prevention Following Hysteroscopic Adhesiolysis in the Improvement of Reproductive Outcomes: A Retrospective Cohort Study

Intrauterine adhesion (IUA) is primarily caused by endometrial injury, and hysteroscopic adhesiolysis is presently the main treatment. However, postoperative recurrence and poor pregnancy outcomes remain intractable. In this study, we aim to assess the effects of different treatments on clinical symptoms and reproductive outcomes in IUA. This retrospective study was conducted in a tertiary university-affiliated women's hospital. The study included 1449 consecutive women who desired to have a baby and were diagnosed with IUA through hysteroscopy from January 2016 to December 2021. Patients with IUA underwent hysteroscopic electric resection (E) or cold scissors separation (C), as well as hormone therapy and one or both of the following secondary prevention measures: intrauterine devices (IUD) and hyaluronic acid gel (HA). The pregnancy rate (PR) was significantly higher in the E + IUD + HA (90.23% CI: 85.82, 94.64%) than in other groups (p = 0.000) groups. The rates of full-term birth (p = 0.000) and live birth (p = 0.000) were significantly higher in the E + IUD + HA (67.82% and 68.97%, respectively) and E + HA (62.41% and 63.91%, respectively) groups. Multivariate logistic regression analysis revealed a significantly higher PR in women who received second-look hysteroscopy (OR 1.571, 95% CI: 1.009-2.224, p = 0.013) and E + IUD + HA (OR 4.772, 95% CI: 2.534-8.987, p = 0.000). Combining hysteroscopic electric resection with IUDs and HA gel could prevent adhesion recurrence and improve postoperative pregnancy and live birth outcomes in IUA. Furthermore, postoperative second-look hysteroscopy may increase the PR and shorten the waiting period.

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.

Adjuvants to prevent reformation of adhesions following adhesiolysis for Asherman syndrome: a systematic review and meta-analysis

Two international guidelines published on the management of Asherman syndrome (AS) have made recommendations on various adjuvant methods to prevent intrauterine reformation. Nevertheless, the effectiveness of these methods when used in primary or secondary prevention settings is different. Our aim is to assess the effectiveness of various adjuvant methods for the secondary prevention of intrauterine adhesions (IUAs). Articles were considered eligible if they included subjects with AS before surgery and compared a chosen method with either a control or a comparison group (using another method). The primary outcome was the IUA reformation rate at follow-up hysteroscopy. A total of 29 studies [15 randomised controlled trials (RCTs) and 14 cohort studies] were included. Adhesion reformation with various methods to prevented IUA reformation when compared with controls were: second-look hysteroscopy: [risk ratio (RR): 0.21, 95% confidence interval (CI): 0.05-0.90 (p = 0.02)]; intrauterine contraceptive device: RR: 0.64, 95% CI: 0.36-1.12 (p = 0.12); continuous intrauterine balloon: RR: 0.18, 95% CI: 0.05-0.68 (p = 0.01); intermittent intrauterine balloon: RR: 0.50, 95% CI: 0.31-0.80 (p = 0.004); anti-adhesion gel: RR: 0.80, 95% CI: 0.58-1.10 (p = 0.17); amnion graft: RR: 0.63, 95% CI: 0.44-0.91 (p = 0.01).

Hysteroscopic Findings and Operative Treatment: All at Once?

Hysteroscopy is considered not only a diagnostic instrument but also a therapeutic tool for many uterine pathologies. In the early 1990s, advances in technology and techniques made hysteroscopy less painful and invasive, allowing to increase in the number of gynecological procedures performed in an ambulatory setting without significant patient discomfort and with potentially significant cost savings. This is the so-called "office hysteroscopy" or "see-and-treat hysteroscopy", whose spread has permitted the decrease of the number of procedures performed in the operating room with the benefit of obviating the need for anesthesia and dilatation of the cervical canal.

Reproductive outcomes of women with moderate to severe intrauterine adhesions after transcervical resection of adhesion: A systematic review and meta-analysis

BACKGROUND

Intrauterine adhesions (IUA) refers to the adhesion of the inner wall of the uterus, resulting in complete or partial occlusion of the uterine cavity, which causes a series of symptoms. Transcervical resection of adhesion (TCRA) is the standard surgical method for patients with IUA. However, the recurrence rate of women with moderate to severe IUA is high and it has raised a big concern about the reproductive outcomes.

METHODS

We conducted a scoping review by using 4 databases, including Google Scholar, PubMed, Scopus, Embase, and web of science, to retrieve relevant literature from September 1, 2001, to February 1, 2023, and to explore the reproductive outcomes in women with moderate to severe IUA after TCRA treatment. Following defined guidelines, data extraction was carried out by 2 researchers, and the findings were examined by 2 senior academics. The papers were evaluated by 2 reviewers using the inclusion and exclusion criteria. Using a form developed especially for this study, pertinent information was retrieved, including the first author, research design, study duration, age, intervention measurement, pregnancy rate, techniques of conception, and live birth rate. Two researchers conducted a quality assessment to determine any potential bias using the Cochrane technique and the Newcastle-Ottawa scale. RevMan 5.4.1 (The Cochrane Collaboration, London, United Kingdom) was used for data analysis, while I2 was used to evaluate heterogeneity.

RESULTS

In total, this study included 2099 participants. After a detailed systematic review and meta-analyses, the results showed that pregnancy and live birth rates were increased significantly after TCRA, and the risk difference of the pregnancy rate was 1.75 [1.17, 2.62]. Besides, in 2 retrospective studies, the risk difference of live birth rate was 2.26, with a 95% confidence interval of 1.99 to 2.58. Moreover, the menstrual status of women also was improved, and the risk difference of hypermenorrhoea and amenorrhea were -0.28 [-0.37, -0.19] and -0.06 [0.26, 0.13], respectively.

CONCLUSIONS

Taken together, TCRA is the useful strategy for the treatment of moderate to severe IUA to enhance the reproductive outcomes in women.

A comparison of special intrauterine balloons and intrauterine contraceptive devices in the treatment of intrauterine adhesions

PURPOSE

This study aimed to compare the efficacy of a special kind of intrauterine balloon (IUB) and that of an intrauterine contraception device (IUD) for patients with intrauterine adhesions (IUAs) after transcervical resection of adhesion (TCRA).

METHODS

In this retrospective cohort study, after TCRA, 31 patients received a special IUB, and 38 patients received an IUD. The Fisher exact test, logistic regression method, Kaplan-Meier method and Cox proportional hazards regression model were used for statistical analysis. A two-sided value of P < 0.05 was considered statistically significant.

RESULTS

The readhesion rate significantly differed between the IUB group and IUD group, at 15.39% and 54.06%, respectively (P = 0.002). For recurrent moderate IUA, patients in the IUB group had lower scores than patients in the IUD group (P = 0.035). There was a significant difference in the intrauterine pregnancy rate of IUA patients in the IUB group and IUD group after treatment, with rates of 55.56% and 14.29%, respectively (P = 0.015).

CONCLUSION

Patients in the special IUB group had better outcomes than those in the IUD group, which has a certain guiding significance for clinical work.

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.

Aldehyde-mediated adaptive membranes with self-healing and antimicrobial properties for endometrial repair

Traditional treatment methods for irreversible endometrial damage face a number of challenges in clinical practice, the most important of which are bacterial infection and the inability to restore endometrial function. By modifying glucan, oxidized dextran (OD) with multifunctional aldehyde groups was obtained in this study. Based on the dynamic Schiff base reaction between gelatin (GA) and OD, a GA-OD adaptive membrane with good biocompatibility, self-healing, biodegradability, and antimicrobial properties was created. In vitro studies revealed that GA and OD cross-linking overcame GA's low gel temperature, accelerated gelling, and improved mechanical properties, hydrophilicity, and degradability. The dynamic bond formed by the reaction between GA and OD caused the GA-OD film to self-heal. Meanwhile, the GA-OD membrane had antibacterial properties. To assess the repair effect of GA-OD film, an in vivo rat endometrial injury model filled with GA-OD adaptive membrane was created. According to the results of the study, the GA-OD membrane was biocompatible, and the uterine tissue did not have edema and inflammation. Further study on the postoperative endometrial regeneration effect of GA-OD material showed that it had an excellent ability for epithelial reconstruction and cell proliferation. As a result, the use of GA-OD composite film in endometrial repair has promising therapeutic implications.

Repairing and Regenerating Injured Endometrium Methods

Good endometrium is the prerequisite and guarantee for reproduction and maternal and child health. Endometrial injury caused by operation or non-operation can lead to menstrual irregularities, amenorrhea, abortion, infertility, and other gynecological diseases to bother women. Intrauterine adhesions (IUA) and thin endometrium are common diseases caused by abnormal repair after endometrium damage. The incidence of IUA is not low after uterine operative surgery, and the recurrence is pretty high after uterine adhesiolysis. At present, there were many methods for endometrial repair in clinic or in the laboratory, but the efficacy was different from methods to methods. They are mainly including estrogen therapy, stem cell therapy, complementary medicine therapy, and some physical barrier therapy. In order to guide the effective repair and regeneration of endometrium in clinic, this paper reviews the merit and demerit of these methods for endometrium regeneration and repair that have been proved to be effective in experiments and clinical in recent years.

Transdermal estrogen gel vs oral estrogen after hysteroscopy for intrauterine adhesion separation: A prospective randomized study

BACKGROUND

This randomized controlled trial (RCT) aimed to compare two different routes of postoperative estrogen treatment on the improvements of menstruation, postoperative endometrial thickness, and fertility outcomes in patients with moderate to severe intrauterine adhesions (IUA).

METHODS

This study prospectively included 78 women (age: 25 to 45 years) with moderate to severe IUA who underwent hysteroscopic resection of adhesions between March 2019 and October 2020. The enrolled patients were randomized 1:1 into either the transdermal gel group (n = 39) or the estradiol valerate oral tablet group (n = 39) on the day of receiving hysteroscopy. Postoperative endometrial thickness, AFS (American Fertility Society) score, estrogen level, and the pattern and amount of menstruation were compared. Pregnancy information was actively collected during 1-year follow-up after the operation.

RESULTS

The postoperative endometrium thickness was improved in both groups, and both groups gained menstruation improvement rates of 67%. For patients who underwent second-look hysteroscopy (17 from the oral group and 19 from the transdermal group), the mean AFS score declined greater than 2 in both groups. For patients with postoperative pregnancy intention, the pregnancy rates at 1-year follow-up after the procedures were 40.5% and 28% in the transdermal group and oral group, respectively. Although no statistically significant difference was observed between the two groups, patients in the transdermal group had a tendency toward increased pregnancy rate.

CONCLUSIONS

Transdermal administration of estrogen is equally efficacious as oral estrogen in postoperative treatment of IUA patients with a relatively safe profile. It is very likely to broaden its indication to the field of IUA.

TRIAL REGISTRATION

http://www.chictr.org.cn/showproj.aspx?proj=37197, identifier ChiCTR1900022110.

Hormonal support in women with Asherman syndrome does not lead to better outcomes: A randomized trial

Purpose

The purpose of the study was to investigate if adjuvant hormones after successful adhesiolysis lead to a reduction in spontaneous recurrence of adhesions and influence reproductive outcomes.

Methods

A single-blind randomized controlled trial comparing administration of oral estrogen (the usual care group) with not giving estrogen (no estrogen) in women after successful adhesiolysis for Asherman syndrome. Women were included between September 2013 and February 2017, with a follow-up of 3 years to monitor recurrences and reproductive outcomes. Analyses were based on an intention to treat analyses. This study was registered under NL9655.

Results

A total of 114 women were included. At 1 year, virtually all patients (except 3) were either having a recurrence or were pregnant. Women who did not receive estrogen did not have more recurrences of adhesions in the first year prior to pregnancy (66.1% in the usual care group, 52.7% in the no-estrogen group, p = 0.15). Of the women in usual care, 89.8% got pregnant within 3 years, and 67.8% got a living child; this was 83.6% and 60.0%, respectively, in the no-estrogen group (p = 0.33 and p = 0.39, respectively).

Conclusion

Usual care does not lead to better outcomes as compared with not giving exogenous estrogen but is associated with side effects.

A LIGHT-HVEM/LTβR axis contributes to the fibrosis of intrauterine adhesion

Intrauterine adhesion (IUA) is a fibrotic disease, with complex and multifactorial process, causing menstrual disorders, pregnancy loss or infertility. LIGHT (also named TNFSF14), mainly expressed by immune cells, has been reported to be associated with tissue fibrosis. However, the features of immunocyte subsets, the expression and roles of LIGHT and its receptor HVEM (herpes virus entry mediator) and LTβR (lymphotoxin beta receptor) in IUA remain largely unknown. Compared with the control group, we observed increased ratios of CD45⁺ cells, neutrophils, T cells, macrophages and decreased natural killer cells proportion, and high LIGHT expression on CD4⁺ T cells and macrophages in IUA endometrium. Further analysis showed there was a positive correlation between upregulated profibrotic factors (e.g., ɑ-smooth muscle actin, transforming growth factor β1) and HVEM in IUA endometrial tissue. More importantly, recombinant human LIGHT protein directly up-regulated the expression of HVEM, LTβR, profibrotic and proinflammatory factors expression in human endometrial stromal cells. These findings reveal abnormal changes of immune cell subsets proportion and the overexpression of LIGHT-HVEM/LTβR axis in IUA endometrium, should contribute to inflammation and fibrosis formation of IUA.

Recent Advances in Treatment of Recurrent Spontaneous Abortion

Importance

Recurrent spontaneous abortion (RSA) is a distressing condition experienced by approximately 1% of women trying to conceive. However, the treatment of RSA is a challenge both for clinicians and patients.

Objective

The aim of this review is to discuss the medical and surgical approach to the management of RSA, including those caused by anatomical, genetic, male, infectious, endocrine, and immune factors.

Evidence Acquisition

A literature search using MeSH terms for each topic was undertaken using PubMed, supplemented by hand searching for additional references. Retrieved articles were reviewed, synthesized, and summarized.

Results

Available treatments target hypothetical risk factors for RSA, although the effectiveness of many treatment options is controversial. Intervention should depend on the benefit-to-risk ratio of the proposed treatment.

Conclusions and Relevance

The etiology of RSA is heterogeneous, and patients often lack specific clinical manifestations, which has hindered the progress in predicting and preventing RSA to some extent. Despite intensive workup, at least 50% of couples do not have a clear underlying pathology. In addition, an evidence-based treatment is not available in most patients even if abnormal test results are present. Many new treatment directions are also still actively exploring; empirical and combined multiple treatments are still the main methods.

Target Audience

Obstetricians and gynecologists, family physicians.

Learning Objectives

After completing this activity, the learner should be better able to describe common risk factors for RSA; formulate individualized treatment plans to improve pregnancy outcomes; and propose supportive treatment recommendations for patients with unclear causes.

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.

Recent trends in therapeutic strategies for repairing endometrial tissue in intrauterine adhesion

Intrauterine adhesion (IUA) is a common gynaecological disease that develops from infection or trauma. IUA disease may seriously affect the physical and mental health of women of childbearing age, which may lead to symptoms such as hypomenorrhea or infertility. Presently, hysteroscopic transcervical resection of adhesion (TCRA) is the principal therapy for IUAs, although its function in preventing the recurrence of adhesion and preserving fertility is limited. Pharmaceuticals such as hormones and vasoactive agents and the placement of nondegradable stents are the most common postoperative adjuvant therapy methods. However, the repair of injured endometrium is relatively restricted due to the different anatomical structures of the endometrium. Recently, the treatment outcome of IUAs has improved with the advancement of hysteroscopic techniques. In particular, the application of bioactive scaffolds combined with tissue engineering technology has proven to have high therapeutic potential or endometrial repair in IUA treatment. Herein, this review has summarized past therapeutic strategies, including postoperative adjuvant therapy, cell or therapeutic molecular delivery therapy methods and bioactive scaffold-based tissue engineering methods. Therefore, this review presented the recent therapeutic strategies for repairing endometrium treatment and pointed out the issues of clinical concern to provide alternative methods for the management of IUAs.

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.

The efficacy of amniotic membrane-mediated sequential double-barrier therapy for the treatment of postoperative intrauterine adhesions

To study the efficacy of using amniotic membrane, balloon and intrauterine device (IUD) as barrier therapy to prevent re-adhesion after hysteroscopic adhesiolysis.A total of 45 patients diagnosed with intrauterine adhesions in Changzhou Maternal and Child Health Hospital from June 2014 to December 2017 were included in this retrospective case control study. According to different postoperative isolation barrier methods, the patients were divided into group A (Foley balloon + fresh amniotic membrane Day1 + IUD Day7) (22 cases) and group B (Foley balloon Day1 + IUD Day7) (23 cases). Three months after the surgery, the second hysteroscopy was performed to observe the condition of the uterine cavity and the improvement of menstruation, and to monitor the thickness of the endometrium.The efficacy of hysteroscopic procedure in group A was significantly higher than that of group B (P < .05). After 3 months of treatment, the improvement rate of menstruation was significantly higher in group A than in group B (P < .05). Endometrial thickness in both group A and B was significantly increased compared with that before the surgery (P < .05). The postoperative endometrium of group A was significantly thicker than that of group B (P < .05).Amniotic membrane-mediated sequential double-barrier method is clinically feasible for preventing recurrent intrauterine adhesions.

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.

A randomized controlled study on an integrated approach to prevent and treat re-adhesion after transcervical resection of moderate-to-severe intrauterine adhesions

OBJECTIVES

This study aims to compare the clinical efficacy of an integrated approach to prevent and treat the recurrence of moderate-to-severe intrauterine adhesions (IUA) after hysteroscopic transcervical resection of adhesion (TCRA).

METHODS

The study included a total of 70 patients with moderate-to-severe IUAs who underwent TCRA. Patients were randomly divided into two groups: treatment group (n=35) and control group n=35). In the treatment group, patients underwent balloon uterine stent placement and artificial cycle as well as received intrauterine perfusion of Danshen injection and oral Chinese medicine. In the control group, patients underwent balloon uterine stent placement and artificial cycle as well as received hyaluronic acid sodium and intrauterine device (IUD). Follow-up was performed after treatment of uterine cavity, menstruation and pregnancy.

RESULTS

After 3 months of treatment, we observed a significantly lower rate of intrauterine re-adhesion (45.71% versus 77.14%, p=0.044) and significantly higher clinical efficiency (82.86% versus 77.14%, p=0.025) in the treatment group than those in the control group. After 6 months of treatment, we observed a significantly higher clinical efficiency in the treatment group than that in the control group (88.57% versus 68.57%, p=0.039). During the follow-up period, the pregnancy rate was 45.71% and 37.14% in the treatment group and control group, respectively, although the difference was not statistically significant (p=0.628).

CONCLUSIONS

After surgical management of IUA, the integrated treatment combining a uterus stent placement and artificial cycle with Danshen injection and oral Chinese medicine can improve the condition of menstruation, and prevent and treat recurrence of IUA.

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.

Auto-Cross-Linked Hyaluronic Acid Gel for Prevention of Intrauterine Adhesions after Hysteroscopic Adhesiolysis: A Randomized Controlled Trial

STUDY OBJECTIVE

To investigate auto-cross-linked hyaluronic acid gel for the prevention of intrauterine adhesion (IUA) recurrence after hysteroscopic adhesiolysis.

DESIGN

A single-center, double-blinded randomized controlled trial.

SETTING

A tertiary university hospital.

PATIENTS

Two hundred seventy-two patients with moderate-to-severe (American Fertility Society [AFS] score ≥5) IUAs underwent hysteroscopic adhesiolysis.

INTERVENTIONS

The patients were randomized to receive standard care along with auto-cross-linked hyaluronic acid gel after surgery (treatment group) or standard care only (control group). All patients had second-look hysteroscopy at 4 weeks and hormonal therapy for 2 cycles after surgery.

MEASUREMENTS AND MAIN RESULTS

Two hundred sixty patients were eligible and randomized; 245 patients successfully completed the study (n = 122 in treatment group, and n = 123 in control group). The primary outcome measure was IUA recurrence at second-look hysteroscopy. The secondary outcome measures included an improvement in the AFS score and menstrual pattern. There was no significant difference with regard to IUA recurrence (31.1% vs 39.8%) or median AFS score at second-look hysteroscopy (2, interquartile range [2-4] vs 2, interquartile range [2-4]) or improvement in the menstrual pattern at 3-month follow-up (87.7% vs 76.4%), in the treatment and control groups, respectively.

CONCLUSION

The application of auto-cross-linked hyaluronic acid gel did not seem to improve IUA recurrence after hysteroscopic adhesiolysis.

An update on stem cell therapy for Asherman syndrome

The current treatment for Asherman syndrome is limited and not very effective. The aim of this review is to summarize the most recent evidence for stem cells in the treatment of Asherman syndrome. The advent of stem cell therapy has propagated experimentation on mice and humans as a novel treatment. The consensus is that the regenerative capacity of stem cells has demonstrated improved outcomes in terms of fertility and fibrosis in both mice and humans with Asherman syndrome. Stem cells have effects on tissue repair by homing to the injured site, recruiting other cells by secreting chemokines, modulating the immune system, differentiating into other types of cells, proliferating into daughter cells, and potentially having antimicrobial activity. The studies reviewed examine different origins and administration modalities of stem cells. In preclinical models, therapeutic systemic injection of stem cells is more effective than direct intrauterine injection in regenerating the endometrium. In conjunction, bone marrow-derived stem cells have a stronger effect on uterine regeneration than uterine-derived stem cells, likely due to their broader differentiation potency. Clinical trials have demonstrated the initial safety and effectiveness profiles of menstrual, bone marrow, umbilical cord, and adipose tissue-derived stem cells in resumption of menstruation, fertility outcomes, and endometrial regeneration.

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.

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.

Secondary Prevention of Intrauterine Adhesions Following Hysteroscopic Surgery in Women With Asherman Syndrome: Is Something Better Than Nothing?

Asherman syndrome is a reproductive disorder characterized by intrauterine adhesions and amenorrhea, infertility, abnormal placentation, or pregnancy loss. Treatment of Asherman syndrome involves hysteroscopic lysis of adhesions. Many surgeons utilize postoperative measures such as hormone therapy, solid mechanical devices, or barrier gels to prevent recurrent adhesions in this setting. However, there is limited high-quality evidence to support their use. Additional research is needed on the safety and efficacy of these commonly used methods to guide patient care.

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.

Optimal waiting period for fresh embryo transfer after hysteroscopic adhesiolysis: a retrospective cohort study

Supplemental Digital Content is available in the text

Background:

Very few studies have been conducted regarding the optimal time interval between hysteroscopic adhesiolysis and the embryo transfer (ET). Investigation of this optimal time may be helpful for assisted reproductive technology. Therefore, we investigated effects of the interval between hysteroscopic adhesiolysis and ET upon in vitro fertilization (IVF) cycle outcomes.

Methods:

Patients were recruited between January 2014 and September 2017 at the Reproductive Hospital Affiliated to Shandong University. Patients who were diagnosed with intra-uterine adhesion (IUA) and underwent hysteroscopic adhesiolysis before fresh IVF-ET or intra-cytoplasmic sperm injection cycles were classified into three groups according to the interval between hysteroscopic adhesiolysis and ET: less than 90 days (Group 1), 90 to 180 days (Group 2), and greater than 180 days (Group 3). Baseline characteristics, controlled ovarian stimulation (COS) response, and pregnancy outcomes after ET were compared. Analysis of variance or non-parametric tests were used to test numerical data. The Pearson's Chi-squared test was used to test categorical data.

Results:

A total of 312 patients were recruited as follows: 112 in Group 1, 137 in Group 2, and 63 in Group 3. There were no differences in baseline and COS characteristics among the three groups. The live-birth rate in Group 2 (40.1%) was significantly higher than that in Group 1 (17.9%; χ² = 14.545, P < 0.001). There were no significant differences in the rates of biochemical, ongoing, and clinical pregnancy, and biochemical and clinical pregnancy abortion, as well as stillbirth among the groups. In the mild IUA patients, the live-birth rate was significantly higher in Group 2 (42.6%) compared with Group 1 (22%; χ² = 8.413, P = 0.004). In the moderate IUA patients, Group 2 (35.7%) had a higher frequency of live births than Group 1 (6.7%; χ² = 8.187, P = 0.004).

Conclusions:

The optimal waiting period for fresh ET after hysteroscopic adhesiolysis was 90 to 180 days in the current study.

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.

Asherman's syndrome: current perspectives on diagnosis and management

Intrauterine adhesions with symptoms like hypomenorrhea or infertility are known under the term Asherman's syndrome. Although the syndrome has been widely investigated, evidence of both prevention of the syndrome and the ideal treatment are missing. Understanding the pathogenesis of intrauterine adherences is necessary for the prevention of the formation of intrauterine scarring. Intrauterine adhesions can develop from lesion of the basal layer of the endometrium caused by curettage of the newly pregnant uterus. The syndrome may also occur after hysteroscopic surgery, uterine artery embolization or uterine tuberculosis. For initial diagnosis the less invasive contrast sonohysterography or hysterosalpingography is useful. The final diagnosis is based on hysteroscopy. Magnetic resonance imaging is required in cases with totally obliterated uterine cavity. Intrauterine adherences are classified in accordance with different classification systems based on the hysteroscopic diagnosis of severity and localization of adherences. Classification is necessary for the planning of surgery, information on prognosis and scientific purposes. Surgery is performed in symptomatic patients with either infertility or with painful periods. Intrauterine adherences are divided with a hysteroscope using scissors or a power instrument working from the central part of the uterus to the periphery. Peroperative ultrasonography is useful in an outpatient setting for the prevention of complications. Hysteroscopy with fluoroscopy is a solution in difficult cases. Use of intrauterine devices like balloon catheters or intrauterine contraceptive devices seems to be the preferred methods for the prevention of re-occurrence of adhesions after treatment. Both primary prevention after hysteroscopic surgery or curettage and secondary prevention of new adhesions after adhesiolysis have been investigated. The aim of this review was to summarize the literature on diagnosis, classification, treatment and prevention, based on a literature search with a wide range of search terms.

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.