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

Etiology, Risk Factors, and Management of Asherman Syndrome

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

Extracellular Vesicles Derived from Mesenchymal Stem Cells as Cell-Free Therapy for Intrauterine Adhesion

Intrauterine adhesion (IUA) can occur after trauma to the basal layer of the endometrium, contributing to severe complications in females, such as infertility and amenorrhea. To date, the proposed therapeutic strategies are targeted to relieve IUA, such as hysteroscopic adhesiolysis, Foley catheter balloon, and hyaluronic acid injection have been applied in the clinic. However, these approaches showed limited effects in alleviating endometrial fibrosis and thin endometrium. Mesenchymal stem cells (MSCs) can offer the potential for endometrium regeneration owing to reduce inflammation and release growth factors. On this basis, MSCs have been proposed as promising methods to treat intrauterine adhesion. However, due to the drawbacks of cell therapy, the possible therapeutic use of extracellular vesicles released by stem cells is raising increasing interest. The paracrine effect, mediated by MSCs derived extracellular vehicles (MSC-EVs), has recently been suggested as a mechanism for their therapeutic properties. Here, we summarizes the main pathological mechanisms involved in intrauterine adhesion, the biogenesis and characteristics of extracellular vesicles, explaining how these vesicles could provide new opportunities for MSCs.

Candida albicans-induced activation of the TGF-β/Smad pathway and upregulation of IL-6 may contribute to intrauterine adhesion

Iatrogenic injury to endometrial tissue is the main cause of intrauterine adhesions (IUA) and infection can also damage the endometrium. The microbiota plays an important role in the health of the female reproductive tract. However, the mechanism is still unclear. In total, 908 patients with IUA and 11,389 healthy individuals were retrospectively selected for this clinical study. Participant information including vaginal microecological results and human papillomavirus (HPV) status were collected. Univariate and multivariate logistic regression analyses were used to identify the factors related to IUA. Next, animal experiments were performed in a curettage-induced IUA rat model. After the procedure, rats in the experimental group received a vaginal infusion of a Candida albicans (C. albicans) fungal solution. On days 3, 7, and 14 after curettage and infusion, the expression levels of IL-6, fibrotic pathway-related factors (TGF-β1, Smad 2, and COL1), and estrogen receptor (ER) and progesterone receptor (PR) in rat endometrial tissues were assessed. Fungal infection of the reproductive tract was found to be an independent risk factor for IUA (P < 0.05). The inflammatory response and degree of fibrosis were greater in rats infected with C. albicans than in the controls. The levels of IL-6, TGF-β1, Smad 2, and COL1 expression in endometrial tissues were significantly higher in the experimental group than in the control group (P < 0.05). However, the ER and PR levels were lower in the IUA group than in the non-IUA group (P < 0.05). C. albicans infection may be related to IUA. C. albicans elicits a strong inflammatory response that can lead to more severe endometrial fibrosis.

Reproductive outcomes and reproductive tract microbiota shift in women with moderate-to-severe intrauterine adhesions following 30-day post-hysteroscopic placement of balloon stents or intrauterine contraceptive devices: A randomized controlled trial

BACKGROUND

Intrauterine adhesions (IUA) develop in up to 20% of women with a history of abortion. After hysteroscopic adhesiolysis, balloon stents are usually placed for seven days to prevent recurrence. The efficacy of prolonged use (30 days) of balloon stents has not been determined.

METHODS

The trial was conducted from June 2019 to March 2021. Ninety-one patients who underwent hysteroscopic adhesiolysis for moderate or severe IUA were randomized to receive a 30-day placement of a balloon stent (n = 44) or an intrauterine device (IUD) (n = 47). The primary outcomes were the ongoing pregnancy and miscarriage rates assessed at 15-19 months. The secondary outcomes were the recurrence of IUA and the American Fertility Society (AFS) intrauterine adhesion scores at the first and second hysteroscopies, the diagnosis of new chronic endometritis at the second-look hysteroscopy, and the vaginal/uterine microbiome assessed using 16S rRNA sequencing. The trial was registered at Chinese Clinical Trial Registry (ChiCTR1900023306).

FINDINGS

The ongoing pregnancy rates (balloon 56·4% versus IUD 57·1%) and miscarriage rates (balloon 10·3% versus IUD 22·9%) were not significantly different between the groups. No differences in the recurrence of IUA, reduction of AFS scores, or new endometritis rates were detected. The bacterial load in the uterus and vagina increased in the IUD group but not in the balloon group.

INTERPRETATION

Balloon placement has a similar effect on ongoing pregnancy rates as intrauterine device (IUD) placement. Patients who underwent balloon placement had a lower miscarriage rate, although the difference was not significant. There were no differences in the recurrence rate of IUA, reduction of American Fertility Society scores, or rate of new chronic endometritis. The balloon stent has less effects on the uterine microbiota.

FUNDING

National Natural Science Foundation of China (81802593).

Peptidome analysis of human intrauterine adhesion tissues and the identification of antifibrotic peptide

Intrauterine adhesion (IUA) is a common clinical endometrial disease, which can severely damage the fertility and quality of life in women. This study aims to find the differentially expressed endogenous peptides and their possible roles in IUA. Liquid chromatography-mass spectrometry was used to identify the peptidomic profiling of IUA tissues, and the differentially expressed peptides were screened out. Using real-time quantitative PCR, Western blotting, and immunocytochemistry staining, the function of six endogenous peptides was verified in vitro. It was found that peptide 6 (T6) (peptide sequence: TFGGAPGFPLGSPLSSVFPR) could inhibit the expression of TGF-β1-induced cell fibrosis in human endometrial stromal cell line and primary human endometrial stromal cell at a concentration of 50 μmol/L. This study provides new targets for further clarifying the formation and prevention of IUA.

Reproductive, Obstetric and Neonatal Outcomes in Women with Congenital Uterine Anomalies: A Systematic Review and Meta-Analysis

Congenital uterine anomalies (CUA) may influence reproductive performance, resulting in adverse pregnancy associated complications. This study aimed to assess the association of CUA subtypes with reproductive, obstetric, and perinatal outcomes. We performed a systematic search of the MEDLINE, EMBASE, and Cochrane libraries for studies comparing pregnancy outcomes between women with CUA and those with a normal uterus. The random effects model was used to estimate the odds ratios (ORs) with a 95% confidence interval (CI). Women with CUA had a lower rate of live births (OR 0.47; 95% CI 0.33-0.69), and a higher rate of first trimester miscarriage (OR, 1.79; 95% CI 1.34-2.4), second trimester miscarriage (OR 2.92; 95% CI 1.35-6.32), preterm birth (OR 2.98; 95% CI 2.43-3.65), malpresentation (OR 9.1; 95% CI 5.88-14.08), cesarean section (OR 2.87; 95% CI 1.56-5.26), and placental abruption (OR 3.12; 95% CI 1.58-6.18). Women with canalization defects appear to have the poorest reproductive performance during early pregnancy. However, unification defects were associated with obstetric and neonatal outcomes throughout the course of pregnancy. It may be beneficial for clinicians to advise on potential complications that may be increased depending on the type and severity of CUA.

Preparation of Fibroblast Suppressive Poly(ethylene glycol)-b-poly(l-phenylalanine)/Poly(ethylene glycol) Hydrogel and Its Application in Intrauterine Fibrosis Prevention

Intrauterine adhesions (IUA) often occur as a result of trauma to the basal layer after curettage, postpartum hemorrhage, or surgical miscarriage. Endometrial fibrosis is the primary pathological feature of IUA. The characteristic features of IUA include excessive deposition and reorganization of the extracellular matrix, replacing the normal endometrium. To prevent uterine fibrosis after injury, we prepared and evaluated a type of fibroblast suppressive hydrogel. Poly(ethylene glycol)-b-poly(l-phenylalanine) (PEBP) copolymers were successfully synthesized by ring opening polymerization of l-Phenylalanine N-carboxyanhydride, initiated by methoxy-poly(ethylene glycol)-amine. Injectable PEBP/PEG hydrogels were subsequently formed through π-π accumulations between PEBP macromolecules and hydrogen bonds among PEBP, PEG, and H₂O molecules. PEBP/PEG hydrogel could suppress the proliferation of fibroblasts due to the action of l-Phe, released sustainably from PEBP/PEG gels. Lastly, the in vivo preventive effect of PEBP/PEG hydrogel on fibrosis was evaluated in a rat uterine curettage model. It was found that PEBP/PEG hydrogel suppressed uterine fibrosis caused by curettage and promoted embryo implantation in injured uterine by regulating the expression and interactions of transforming growth factor beta 1 (TGF-β1) and Muc-4. PEBP/PEG hydrogels have the potential for application in uterine adhesion prevention owing to their fibrosis preventive and pregnancy promotiing effects on uterine tissue after injury.

A New Thermo-Responsive Hyaluronic Acid Sol-Gel to Prevent Intrauterine Adhesions after Hysteroscopic Surgery: A Randomized, Non-Inferiority Trial

PURPOSE

To investigate the efficacy and safety of a newly developed thermo-responsive sol-gel, ABT13107, for reducing the formation of intrauterine adhesions (IUAs) after hysteroscopic surgery.

MATERIALS AND METHODS

In this multicenter, prospective, randomized trial (Canadian Task Force classification I), 192 women scheduled to undergo a hysteroscopic surgery at one of the eight university hospitals in South Korea were randomized into the ABT13107 group or the comparator (Hyalobarrier®) group in a 1:1 ratio. During hysteroscopic surgery, ABT13107 or Hyalobarrier® was injected to sufficiently cover the entire intrauterine cavity.

RESULTS

The patients returned to their respective sites for safety assessments at postoperative weeks 1 and 4 and for efficacy assessments at postoperative week 4. The post-surgery incidence of IUAs was 23.4% in the ABT13107 group and 25.8% in the comparator group; this difference met the criteria for ABT13107 to be considered as not inferior to the comparator. No differences were found in the extent of adhesions, types of adhesions, or the cumulative American Fertility Society score between the two treatment groups. Most adverse events were mild in severity, and no serious adverse events occurred.

CONCLUSION

ABT13107, a new anti-adhesive barrier containing hyaluronic acid, was not inferior to the highly viscous hyaluronic acid anti-adhesive barrier, Hyalurobarrier® in IUA formation after hysteroscopic surgery (Clinical trial registration No. NCT04007211).

The Effect of Mitomycin C on Reducing Endometrial Fibrosis for Intrauterine Adhesion

<strong>BACKGROUND</strong> Intrauterine adhesion (IUA) is a common reproductive system disease in women, characterized by endometrial stromal cell proliferation, increasing fibroblasts and increasing extracellular matrix secretion. The purpose of this study was to investigate the effect of mitomycin C on reducing endometrial fibrosis for IUA. <strong>MATERIAL AND METHODS</strong> Firstly, a rat IUA model was constructed by intrauterine mechanical injury. The endometrial stromal cells and fibroblasts were isolated and treated with mitomycin C. After that, Cell Counting Kit-8 (CCK-8) assay was used to investigate the endometrial stromal cell viability. Furthermore, cell cycle and apoptosis assays of endometrial stromal cells and fibroblasts were performed, respectively. Finally, the cell viability of human endometrial cells or human uterus adhesion fibroblasts treated with mitomycin C was determined using CCK-8 assay with or without estradiol. <strong>RESULTS</strong> Endometrial stromal cells were isolated from a rat IUA model. Cell cycle assay results showed that mitomycin C inhibited cell viability and promoted G1 cell cycle arrest and apoptosis in rat IUA endometrial stromal cells. Fibroblasts were also isolated from the rat IUA model. We found that mitomycin C inhibited the synthesis and secretion of collagen type I by western blotting analysis. Furthermore, mitomycin C promoted G1 cell cycle arrest and apoptosis in IUA rat uterine fibroblasts. We found that estradiol decreased the inhibitory effects of cell viability of human endometrial cells and human uterus adhesion fibroblasts by mitomycin C. <strong>CONCLUSIONS</strong> Our findings revealed that mitomycin C could reduce endometrial fibrosis for intrauterine adhesion.

Silicone Plate for the Prevention of Postoperative Adhesions in Patients with Asherman Syndrome

PURPOSE

Re-adhesion rates following hysteroscopic adhesiolysis have remained high. Accordingly, we present a case involving temporary placement of an intrauterine silicone plate to prevent re-adhesions following hysteroscopic adhesiolysis in a 36-year-old woman with Asherman syndrome.

METHODS

After hysteroscopic adhesiolysis, a silicone plate molded to the uterine cavity's shape was inserted into the uterine cavity and left in place for 1 month.

RESULTS

The patient had a history of endometrial curettage for endometrial polyps. After the procedure, she developed amenorrhea and experienced infertility for 5 years despite four cycles of in vitro fertilization and embryo transfer. Following admission to our hospital, hysteroscopic examination showed a wide area of intrauterine adhesions for which hysteroscopic adhesiolysis and silicone plate insertion were performed. The silicone plate was removed after 1 month. No intrauterine adhesions were observed during the subsequent hysteroscopic examination. After a thawed embryo transfer, the patient became pregnant and delivered a healthy baby.

CONCLUSIONS

A silicon plate may be considered a useful tool for preventing re-adhesion following hysteroscopic adhesiolysis without serious complications.

Efficacy of a New Crosslinked Hyaluronan Gel in the Prevention of Intrauterine Adhesions

Background and Objectives:

The authors sought to assess the effect of the use of a new crosslinked hyaluronan (NCH) gel on the prevention of intrauterine adhesions (IUAs) in women underwent curettage in the second trimester.

Methods:

Between June 2016 and September 2017, 60 patients who underwent curettage for retained placental tissue after medically induced or spontaneous pregnancy loss in the second trimester were enrolled in the study. The patients were randomly assigned to 1 of 2 groups: Group 1 patients received curettage plus NCH gel (intervention group), and group 2 patients received curettage alone (control group). The main outcomes were the rate and severity of IUA formation, which were assessed by follow-up hysteroscopy performed in the ensuing 2–6 months.

Results:

The hysteroscopic findings were available for 20 patients in group 1 and 28 patients in group 2. IUAs were observed in 6 patients in group 2, while no IUAs was observed in group 1 (P = .007). IUAs were staged as mild in 4 patients (14.28%) and moderate in 2 patients (7.14%) in group 2 according to the American Fertility Society classification of IUAs.

Conclusions:

Our study demonstrates that NCH gel appears to be able to reduce the formation of IUAs in women who undergo curettage in the second trimester, although larger controlled, randomized, multicenter studies are needed to confirm these results.

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.

Effects of Aspirin and Intrauterine Balloon on Endometrial Repair and Reproductive Prognosis in Patients with Severe Intrauterine Adhesion: A Prospective Cohort Study

This study aimed to investigate the effects of estrogen in combination with aspirin and intrauterine balloon on the uterine endometrial repair and reproductive prognosis in patients after surgery for severe intrauterine adhesion (sIUA). We prospectively recruited 114 patients with sIUA. Intrauterine device (IUD) was placed and oral estrogen was administered after surgery. Patients were divided into control group and aspirin group. In addition, patients in aspirin group were subdivided into nonballoon group and balloon group. Results showed that, after therapy, the increase in endometrial thickness of aspirin groups was superior to control group (P < 0.05). The scores of intrauterine adhesion and menstruation were significantly improved in balloon group as compared to nonballoon group and control group, and significant differences were also observed between nonballoon group and control group (P < 0.05). Of 97 patients, 44.3% became pregnant after surgery, the live birth rate was 27.8%, and the miscarriage rate was 37.2%, but there were no significant differences among three groups (P > 0.05). Thus, aspirin may promote the uterine endometrial growth and repair after surgery for sIUA, and IUD in combination with intrauterine balloon may reduce the recurrence of intrauterine adhesion, but their effect on the reproductive prognosis is required to be further studied.

Uterine fibroid management: from the present to the future

Uterine fibroids (also known as leiomyomas or myomas) are the most common form of benign uterine tumors. Clinical presentations include abnormal bleeding, pelvic masses, pelvic pain, infertility, bulk symptoms and obstetric complications.Almost a third of women with leiomyomas will request treatment due to symptoms. Current management strategies mainly involve surgical interventions, but the choice of treatment is guided by patient's age and desire to preserve fertility or avoid 'radical' surgery such as hysterectomy. The management of uterine fibroids also depends on the number, size and location of the fibroids. Other surgical and non-surgical approaches include myomectomy by hysteroscopy, myomectomy by laparotomy or laparoscopy, uterine artery embolization and interventions performed under radiologic or ultrasound guidance to induce thermal ablation of the uterine fibroids.There are only a few randomized trials comparing various therapies for fibroids. Further investigations are required as there is a lack of concrete evidence of effectiveness and areas of uncertainty surrounding correct management according to symptoms. The economic impact of uterine fibroid management is significant and it is imperative that new treatments be developed to provide alternatives to surgical intervention.There is growing evidence of the crucial role of progesterone pathways in the pathophysiology of uterine fibroids due to the use of selective progesterone receptor modulators (SPRMs) such as ulipristal acetate (UPA). The efficacy of long-term intermittent use of UPA was recently demonstrated by randomized controlled studies.The need for alternatives to surgical intervention is very real, especially for women seeking to preserve their fertility. These options now exist, with SPRMs which are proven to treat fibroid symptoms effectively. Gynecologists now have new tools in their armamentarium, opening up novel strategies for the management of uterine fibroids.