Should we consider alternative therapies to operative hysteroscopy for the treatment of Asherman syndrome?

The humanin analogue (HNG) alleviates intrauterine adhesions by inhibiting endometrial epithelial cells ferroptosis: a rat model-based study

STUDY QUESTION

Does a humanin analogue (HNG) have a therapeutic effect on intrauterine adhesions (IUAs) caused by uterine cavity surgery in a rat model?

SUMMARY ANSWER

HNG supplementation attenuated the development of endometrial fibrosis and IUAs, improved fertility, and contributed to the regulation of endometrial fibrosis by inhibiting endometrial ferroptosis in rats with IUAs.

WHAT IS KNOWN ALREADY

IUAs, which are characterized by endometrial fibrosis, are a common cause of female infertility. Humanin (rattin in rats) is a mitochondrial-derived peptide that is widely expressed in multiple tissues. S14G-humanin (HNG) is an HNG that has been reported to have a protective effect against myocardial fibrosis.

STUDY DESIGN, SIZE, DURATION

Endometrial tissues from three patients with IUAs and three controls were tested for humanin expression. Two animal models were used to evaluate the modelling effect of IUAs and the preventive effect of HNG against IUAs. In the first model, 40 rats were equally randomized to control and Day 7, 14, and 21 groups to establish the IUA model. In the second model, 66 rats were equally randomized to the control, IUA, and IUA + humanin analogue (HNG) groups. Erastin was used to induce ferroptosis in the Ishikawa cell line.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The endometrium was scraped with a surgical spatula, combined with lipopolysaccharide treatment, to establish the rat model of IUAs. Rats were intraperitoneally injected with 5 mg/kg/day HNG for 21 consecutive days beginning from the day of operation to evaluate the therapeutic effect on IUAs. Haematoxylin-eosin and Masson's trichrome staining were used to assess endometrial morphology and evaluate fibrosis. Ferroptosis-related markers, namely nuclear factor E2-related factor 2 (Nrf2), acyl-CoA synthetase long-chain family member 4 (ACSL4), haeme oxygenase-1 (HO-1), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and ferritin, were measured by immunohistochemistry and western blotting to determine whether ferroptosis was involved in the development of IUAs and to assess the attenuative effect of HNG on ferroptosis. Additionally, the female rats were mated with male rats with normal fertility to assess fertility.

MAIN RESULTS AND THE ROLE OF CHANCE

Humanin was widely expressed in endometrial cells, including epithelial and stromal cells, in both humans and rats. Humanin expression levels were downregulated in the endometria of patients and rats with IUAs relative to the endometria of controls. Endometrial thickness and the number of glands were significantly decreased on Day 7, 14, and 21 after endometrial scraping when compared with the controls (all P < 0.05), whereas the fibrotic area was significantly increased (P < 0.05). Among the tested ferroptosis markers, the expression levels of Nrf2, SLC7A11, and GPX4 were significantly downregulated and those of ACSL4, HO-1, and ferritin were significantly upregulated after endometrial scraping relative to their expression levels in controls (all P < 0.05). The mating rates in the control, IUA, and IUA + HNG groups were 100% (10/10), 40% (4/10), and 80% (8/10), respectively. The number of embryos in rats with IUAs (mean ± SD: 1.6 ± 2.1) was significantly less than the number in the controls (11.8 ± 1.5). HNG supplementation significantly attenuated this decrease in the number of implanted embryos (6.3 ± 4.5) (P < 0.01). Further results showed that HNG significantly attenuated the altered expression levels of proteins involved in ferroptosis in the endometria of rats with IUAs. Moreover, in vitro experiments showed that HNG significantly attenuated the erastin-induced decrease in the viability of the Ishikawa cell line and also attenuated the increase in reactive oxygen species production and the downregulation of GPX4.

LARGE SCALE DATA

None.

LIMITATIONS, REASONS FOR CAUTION

The findings of this study showed that HNG inhibited ferroptosis and reduced fibrosis in a rat model of IUAs. However, we could not establish a causal relationship between ferroptosis and the development of IUAs.

WIDER IMPLICATIONS OF THE FINDINGS

HNG may be effective at alleviating fibrosis during the development of IUAs, and the inhibition of ferroptosis is a promising new strategy for IUA therapy.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Natural Science Foundation of China (No. 82171647); the '1000 Talent Plan' of Yunnan Province (No. RLQN20200001); and the Basic Research Project of the Yunnan Province-Outstanding Youth Foundation (No. 202101AW070018). The authors declare no competing financial interests.

Human endometrium-derived mesenchymal stem/stromal cells application in endometrial-factor induced infertility

Endometrial-factor induced infertility remains one of the most significant pathology among all fertility disorders. Stem cell-based therapy is considered to be the next-generation approach. However, there are still issues about successfully retrieving human endometrium-derived mesenchymal stem/stromal cells (hEnMSCs). Moreover, we need to establish a better understanding of the effect of hEnMSCs on the endometrial recovery and the clinical outcome. According to these challenges we created a multi-step study. Endometrium samples were collected from females undergoing assisted reproductive technology (ART) procedure due to couple infertility. These samples were obtained using an endometrium scratching. The hEnMSCs were isolated from endometrium samples and characterized with flow cytometry analysis. Groups of endometrium injured female mice were established by the mechanical injury to uterine horns and the intraperitoneal chemotherapy. The hEnMSCs suspension was injected to some of the studied female mice at approved time intervals. Histological changes of mice uterine horns were evaluated after Masson's trichrome original staining, hematoxylin and eosin (H&E) staining. The fertility assessment of mice was performed by counting formed embryo implantation sites (ISs). The expression of fibrosis related genes (Col1a1, Col3a1, Acta2, and CD44) was evaluated by the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results showed that endometrium scratching is an effective procedure for mesenchymal stem/stromal cells (MSCs) collection from human endometrium. Isolated hEnMSCs met the criteria for defining MSCs. Moreover, hEnMSCs-based therapy had a demonstrably positive effect on the repair of damaged uterine horns, including a reduction of fibrosis, intensity of inflammatory cells such as lymphocytes and polymorphonuclear cells (PMNs) and the number of apoptotic bodies. The injured mice which recieved hEnMSCs had higher fertility in comparison to the untreated mice. Gene expression was reflected in histology changes and outcomes of conception. In conclusion, hEnMSCs demonstrated a positive impact on endometrium restoration and outcomes of endometrial-factor induced infertility. Further exploration is required in order to continue exploring the multifactorial associations between stem cell therapy, gene expression, endometrial changes and reproductive health, so we can identify individually effective and safe treatment strategies for endometrial-factor induced infertility, which is caused by mechanical effect or chemotherapy, in daily clinical practise.

Asherman Syndrome after Uterine Artery Embolization: A Cohort Study about Surgery Management and Fertility Outcomes

STUDY OBJECTIVE

To study the severity of intrauterine adhesions (IUA) after uterine arterial embolization and to evaluate fertility, pregnancy, and obstetrical outcomes after hysteroscopic treatment.

DESIGN

Retrospective cohort.

SETTING

French University Hospital.

PATIENTS

Thirty-three patients under the age of 40 years who were treated by uterine artery embolization with nonabsorbable microparticles between 2010 and 2020 for symptomatic fibroids or adenomyosis, or postpartum hemorrhage.

INTERVENTIONS

All patients had a diagnosis of IUA after embolization. All patients desired future fertility. IUA was treated with operative hysteroscopy.

MEASUREMENTS AND MAIN RESULTS

Severity of IUA, number of operative hysteroscopies performed to obtain a normal cavity shape, pregnancy rate, and obstetrical outcomes. Of our 33 patients, 81.8% had severe IUA (state IV et V according to the European Society of Gynecological Endoscopy or state III according to the American fertility society classification). To restore fertility potential, an average of 3.4 operative hysteroscopies had to be performed [CI 95% (2.56-4.16)]. We reported a very low rate of pregnancy (8/33, 24%). Obstetrical outcomes reported are 50% of premature birth and 62.5% of delivery hemorrhage partly due to 37.5% of placenta accreta. We also reported 2 neonatal deaths.

CONCLUSION

IUA after uterine embolization is severe, and more difficult to treat than other synechiae, probably related to endometrial necrosis. Pregnancy and obstetrical outcomes have shown a low pregnancy rate, an increased risk of preterm delivery, a high risk of placental disorders, and very severe postpartum hemorrhage. Those results have to alert gynecologists and radiologists to the use of uterine arterial embolization in women who desire future fertility.

The perinatal outcomes of women treated for Asherman syndrome: a propensity score-matched cohort study

STUDY QUESTION

Do the perinatal outcomes of patients following hysteroscopic treatment for Asherman syndrome (AS) differ from that of a control population?

SUMMARY ANSWER

Perinatal complications including placental issues, high blood loss, and prematurity in women after treatment for AS should be considered as moderate to high risk, especially in patients who have undergone more than one hysteroscopy (HS) or repeated postpartum instrumental revisions of the uterine cavity (Dilation and Curettage; D&C).

WHAT IS KNOWN ALREADY

The detrimental impact of AS on obstetrics outcomes is commonly recognized. However, prospective studies evaluating perinatal/neonatal outcomes in women with AS history are sparse, and the characteristics accounting for the respective morbidity of AS patients remain to be elucidated.

STUDY DESIGN, SIZE, DURATION

We conducted a prospective cohort study utilizing data from patients who underwent HS treatment for moderate to severe AS in a single tertiary University-affiliated hospital (enrolled between 01 January 2009 and March 2021), and who consequently conceived and progressed to at least 22nd gestational week of pregnancy. Perinatal outcomes were compared to a control population without an AS history, retrospectively enrolled concomitantly at the time of delivery for each patient with AS. Maternal and neonatal morbidity was assessed as well as the characteristics-related risk factors of AS patients.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Our analytic cohort included a total of 198 patients, 66 prospectively enrolled patients with moderate to severe AS and 132 controls. We used multivariable logistic regression to calculate a propensity score to match 1-1 women with and without AS history based on demographic and clinical factors. After matching, 60 pairs of patients were analysed. Chi-square test was used to compare perinatal outcomes between the pairs. Spearman's correlation analysis was utilized to investigate the correlation between perinatal/neonatal morbidity and the characteristics-related factors of AS patients. The odds ratio (OR) for the associations was calculated by logistic regression.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 60 propensity matched pairs, the AS group more frequently experienced overall perinatal morbidity, including abnormally invasive placenta (41.7% vs 0%; P < 0.001), retained placenta requiring manual or surgical removal (46.7% vs 6.7%; P < 0.001), and peripartum haemorrhage occurrence (31.7% vs 3.3%; P < 0.001). Premature delivery (<37 gestational weeks) was reported more frequently also for patients with AS (28.3% vs 5.0%; P < 0.001). However, no increased frequency of intra-uterine growth restriction or worsened neonatal outcomes were observed in AS group. Univariable analysis of risk factors for AS group morbidity outcomes revealed that the main factor related to abnormally invasive placenta was two or more HS procedures (OR 11.0; 95% CI: 1.33-91.23), followed by two or more D&Cs preceding AS treatment (OR 5.11; 95% CI: 1.69-15.45), and D&C performed postpartum as compared to post abortion (OR 3.0; 95% CI: 1.03-8.71). Similarly, two or more HS procedures were observed as the most important factor for retained placenta (OR 13.75; 95% CI: 1.66-114.14), followed by two or more preceding D&Cs (OR 5.16; 95% CI: 1.67-15.9). Premature birth was significantly associated with the number of preceding D&Cs (OR for two or more, 4.29; 95% CI: 1.12-14.91).

LIMITATIONS, REASONS FOR CAUTION

Although the cohort of patients with AS was enrolled prospectively, a baseline imbalance was intrinsically involved in the retrospective enrolment of the control group. However, to reduce the risk of bias, confounding factors were adjusted for using propensity score matching. The limitation to the generalization of our reported results is the single institution design in which all patients were treated for AS in one tertiary medical centre.

WIDER IMPLICATIONS OF THE FINDINGS

Within our search scope, our study represents one of the first and largest prospective studies of perinatal and neonatal outcomes in moderate to severe AS patients with a prospectively analysis of the risks factors of characteristics significantly influencing reported morbidities among patients with AS.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by the Charles University in Prague [UNCE 204065] and by the institutional grant of The General Faculty Hospital in Prague [00064165]. No competing interests were declared.

TRIAL REGISTRATION NUMBER

N/A.

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

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

The Top 100 Most Cited Articles on Intrauterine Adhesion: a Bibliometric Analysis

Bibliometric analysis is a statistical method that attempts to assess articles by their citations, analyzing their frequency and citation pattern, which subsequently gleans direction and guidance for future research. Over the past few years, articles focused on intrauterine adhesions have been published with increasing frequency. Nevertheless, little is known about the properties and qualities of this research, and no current analysis exists that has examined the progress in intrauterine adhesion research. Web of Science Core Collection, BIOSIS Citation Index, and MEDLINE database were searched to identify articles on intrauterine adhesion published from 1950 to October 2020. The 100 most cited articles were chosen to analyze citation count, citation density, authorship, theme, geographic distribution, time-related flux, level of evidence, and network analysis. An overwhelming majority of these 100 articles were published in the 2010s (35%). Citations per article ranged from 30 to 253. Chinese authors published the most papers in the top 100, followed by the USA, France, Israel, and Italy. The most salient study themes included operative hysteroscopy and adjunctive treatments for improving reproductive outcomes. The most common level of evidence was level II, and there was no statistical difference in the number of citations between the levels. The network analysis indicated that hysteroscopy, hysteroscopic adhesiolysis, infertility, and the reproductive outcome had a great degree of centrality in the 2000s and 2010s. In comparison, placental implantation had a great degree of centrality in the 2000s, and stem cell and fibrosis had a great degree of centrality in the 2010s. The value of IUA investigation has been gradually appreciated recently. Hysteroscopic adhesiolysis was continuously explored to achieve better reproductive outcome. Over time, the main focus of research has gradually shifted from complications to postoperative adjuvant treatment. Moreover, breakthrough progress is needed in underlying mechanism and early prevention of IUA.

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.

[Treatment of synechiae related to infertility]

Synechiae are intrauterine adhesions that affect the fertility of women. They are most often of post-traumatic origin. The management of pregnancy abortions in the first trimester and post-delivery retention are the main contributing factors. Synechiae is responsible for cycle disorders and repeated pregnancy loss. Hysteroscopy is the reference method for its diagnosis and treatment. The surgical objective is the restoration of a normal sized cavity and a functional endometrium to allow fertilization and implantation. The use of small diameter (5mm) hysteroscopes and no energy or bipolar energy instruments are recommended. Echo guidance facilitates the treatment of severe synechiae and limits the risk of intraoperative perforation. The main risk of treatment is recurrence, particularly in severe cases where multiple operating times are sometimes necessary. An office hysteroscopy at 6 weeks is recommended to identify and treat these recurrences. Different physical, molecular or cellular methods are studied as primary and secondary prevention of postoperative synechiae. The objective of this review is to provide an update on the treatment of synechiae in the context of infertility.

Endometrial thickness measurements among Asherman syndrome patients prior to embryo transfer

STUDY QUESTION

Is there an association between endometrial thickness (EMT) measurement and clinical pregnancy rate among Asherman syndrome (AS) patients utilizing IVF and embryo transfer (ET)?

SUMMARY ANSWER

EMT measurements may not be associated with successful clinical pregnancy among AS patients undergoing IVF.

WHAT IS KNOWN ALREADY

Clinical pregnancy rate after IVF is significantly lower in patients with a thin endometrium, defined as a maximum EMT of <7 mm. However, AS patients often have a thin EMT measurement due to intrauterine scarring, with a paucity of data and no guidance on what EMT cutoff is appropriate when planning an ET among these patients.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort study of 45 AS patients treated at a specialized advanced hysteroscopic clinic from 1 January 2015, to 1 March 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Review of EMT measurements prior to a total of 90 ETs, among 45 AS patients. The impact of the maximum EMT measurement prior to ET on clinical pregnancy rate was analyzed.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 25/45 (55.6%) AS patients ultimately went on to have ≥1 clinical pregnancy following a mean ± SD of 2.00 ± 1.26 ET attempts. There was a total of 90 ETs among the 45 AS patients, with 29/90 (32.2%) ETs resulting in a clinical pregnancy. Younger patient age (P = 0.05) and oocyte donation (P = 0.01) were the only variables identified to be significant predictors for a positive clinical pregnancy outcome on bivariate analysis. The mean EMT measurement prior to all ETs among AS patients was 7.5 ± 1.6 mm. EMT measurement prior to ET did not predict a positive clinical pregnancy on either bivariate (P = 0.84) or multivariable analysis (odds ratio 0.91, P = 0.60). 31.8% of EMT measurements measured <7.0 mm. In this small cohort, no difference in the clinical pregnancy rate was detected when comparing ETs with EMT measurements of <7.0 mm versus ≥7.0 mm (P = 0.83). The mean EMT measurement decreased with increasing AS disease severity; 8.0 ± 1.6 mm for mild disease, 7.0 ± 1.4 mm for moderate disease and 5.4 ± 0.1 mm for severe disease.

LIMITATIONS, REASONS FOR CAUTION

Our small sample size limits our ability to draw any definitive conclusions. In addition, patients utilized various infertility clinics. This limits our ability to evaluate the consistency of EMT measurements and the IVF care that was received.

WIDER IMPLICATIONS OF THE FINDINGS

EMT measurement cutoff values should be used with caution if canceling a scheduled ET in AS patients.

STUDY FUNDING/COMPETING INTEREST(S)

This study was not funded. K.I. reports personal fees from Karl Stroz and personal fees from Medtronics outside the submitted work. The other authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.