Comprehensive analysis of circRNA-miRNA-mRNA regulatory network and novel potential biomarkers in eutopic endometrium of adenomyosis.

Adenomyosis (ADS) is a common gynecological disorder, and its pathogenesis remains unclear. This study explores the functions of circRNAs in the eutopic endometrium of ADS and their diagnostic efficacy for ADS. High-throughput RNA sequencing was performed on 12 eutopic endometrial samples from ADS patients and 3 control endometrial samples. Additionally, circRNAs were analyzed in conjunction with clinical features. A competitive endogenous RNA network was established based on bioinformatics analysis, comprising 3 circRNAs, 1 miRNA, and 13 mRNAs. In the ADS group, the expression levels of hsa_circ_0008959 and SLC15A4 were significantly reduced, while hsa-miR-124-3p expression was increased. SLC15A4 was associated with cell proliferation and invasion. Decreased expression of hsa_circ_0008959 and SLC15A4, along with high VAS scores and elevated hsa-miR-124-3p levels, were identified as risk factors for ADS development. The combination of hsa_circ_0008959 and VAS scores demonstrated the highest diagnostic value for ADS.

Paradoxical role of phosphorylated STAT3 in normal fertility and the pathogenesis of adenomyosis and endometriosis†.

Signal transducer and activator of transcription 3 (STAT3), when phosphorylated at tyrosine 705, plays an important role in endometrial stromal cell decidualization and the receptivity of the endometrial epithelium during embryo implantation. However, the function of phosphorylated STAT3 (p-STAT3) in normal uterine receptivity is distinct from that in adenomyosis and endometriosis. In normal pregnancy, STAT3 phosphorylation in the endometrial epithelium determines the success of embryo implantation by regulating uterine receptivity. Additionally, p-STAT3 promotes cellular proliferation and differentiation during endometrial decidualization, which is crucial for embryonic development. In contrast, excessive STAT3 phosphorylation occurs in adenomyosis and endometriosis, which may lead to disease progression. Therefore, achieving a delicate balance in STAT3 activation is crucial. This review aimed to focus on the current understanding and knowledge gaps regarding the control of p-STAT3 activity in normal and pathological endometrial processes. This topic is important because precise control of p-STAT3 production could alleviate the symptoms of adenomyosis and endometriosis, improve endometrial receptivity, and potentially mitigate infertility without compromising normal fertility processes.

The pathogenesis of endometriosis and adenomyosis: insights from single-cell RNA sequencing†.

Endometriosis and adenomyosis are two similar gynecological diseases that are characterized by ectopic implantation and the growth of the endometrial tissue. Previous studies have reported that they share a common pathophysiology in some respects, such as a similar cellular composition and resistance to the progestogen of lesions, but their underlying mechanisms remain elusive. Emerging single-cell ribonucleic acid sequencing (scRNA-seq) technologies allow for the dissection of single-cell transcriptome mapping to reveal the etiology of diseases at the level of the individual cell. In this review, we summarized the published findings in research on scRNA-seq regarding the cellular components and molecular profiles of diverse lesions. They show that epithelial cell clusters may be the vital progenitors of endometriosis and adenomyosis. Subclusters of stromal cells, such as endometrial mesenchymal stem cells and fibroblasts, are also involved in the occurrence of endometriosis and adenomyosis, respectively. Moreover, CD8+ T cells, natural killer cells, and macrophages exhibit a deficiency in clearing the ectopic endometrial cells in the immune microenvironment of endometriosis. It seems that the immune responses are activated in adenomyosis. Understanding the immune characteristics of adenomyosis still needs further exploration. Finally, we discuss the application of findings from scRNA-seq for clinical diagnosis and treatment. This review provides fresh insights into the pathogenesis of endometriosis and adenomyosis as well as the therapeutic targets at the cellular level.

Activation of HAND2-FGFR signaling pathway by lncRNA HAND2-AS1 in adenomyosis†.

Heart and neural crest derivatives expressed transcript 2 (HAND2) is a critical mediator of progesterone action in endometrial stromal cells. Silencing of Hand2 expression in mouse uterus leads to an unopposed FGFR-mediated action that causes female mice infertility. To investigate the involvement of HAND2-FGFR signaling in pathogenesis of adenomyosis, immunohistochemistry, in situ hybridization, and quantitative real-time PCR were employed to assess gene expression in the normal endometrium, the paired eutopic endometrium and ectopic lesions obtained from women with adenomyosis. DNA methylation in the regions of HAND2 promoter and the first exon was also monitored in these samples. Our results revealed that HAND2 expression were dramatically reduced, but FGF9 expression and FGFR-ERK1/2-mediated MAPK signaling pathway were enhanced in the eutopic endometrium and ectopic lesions of patients with adenomyosis compared to the normal controls. Interestingly, expression of HAND2-AS1, a long noncoding RNA that resides adjacent to HAND2 in genome, was also reduced in adenomyosis. DNA methylation analysis revealed that the bidirectional promoter between HAND2 and HAND2-AS1, and the first exon of HAND2 gene was heavily methylated in the eutopic endometrium and the ectopic lesions of adenomyosis. To investigate the regulation of gene expression by HAND2-AS1, HAND2-AS1 expression was silenced in human endometrial stromal cells. In contrast to the downregulation of HAND2 in response to HAND2-AS1 silencing, FGF9 expression was augmented significantly. Endometrial stromal cells lacking HAND2-AS1 exhibited enhanced proliferation and migration potentials. Collectively, our studies revealed a new molecular mechanism by which HAND2-AS1 is involved in the pathogenesis of adenomyosis via modulating HAND2-FGFR-mediated signaling.

Extracellular vesicle-encapsulated miR-25-3p promotes epithelial-mesenchymal transition and migration of endometrial epithelial cells by inducing macrophage polarization.

The pathogenesis of adenomyosis is closely related to the epithelial-mesenchymal transition and macrophages. MicroRNAs have been extensively investigated in relation to the epithelial-mesenchymal transition in a range of malignancies. However, there is a paucity of research on extracellular vesicles derived from the eutopic endometrium of adenomyosis and their encapsulated microRNAs. In this study, we investigated the role of microRNA-25-3p derived from extracellular vesicles in inducing macrophage polarization and promoting the epithelial-mesenchymal transition in endometrial epithelial cells of patients with adenomyosis and controls. We obtained eutopic endometrial samples and isolated extracellular vesicles from the culture supernatant of primary endometrial cells. Real-time quantitative PCR analysis demonstrated that microRNA-25-3p was highly expressed in extracellular vesicles, as well as in macrophages stimulated by extracellular vesicles from eutopic endometrium of adenomyosis; and macrophages transfected with microRNA-25-3p exhibited elevated levels of M2 markers, while displaying reduced levels of M1 markers. After co-culture with the above polarized macrophages, endometrial epithelial cells expressed higher levels of N-cadherin and Vimentin, and lower protein levels of E-cadherin and Cytokeratin 7. It was revealed that microRNA-25-3p encapsulated in extracellular vesicles from eutopic endometrial cells could induce macrophage polarization toward M2, and the polarized macrophages promote epithelial-mesenchymal transition in epithelial cells. However, in vitro experiments revealed no significant disparity in the migratory capacity of endometrial epithelial cells between the adenomyosis group and the control group. Furthermore, it was observed that microRNA-25-3p-stimulated polarized macrophages also facilitated the epithelial-mesenchymal transition and migration of endometrial epithelial cells within the control group. Thus, the significance of microRNA-25-3p-induced polarized macrophages in promoting the development of adenomyosis is unclear, and macrophage infiltration alone may be adequate for this process. We emphasize the specificity of the local eutopic endometrial microenvironment and postulate its potential significance in the pathogenesis of adenomyosis.

Vaginal microbiome differences between patients with adenomyosis with different menstrual cycles and healthy controls.

BACKGROUND: Adenomyosis is a commonly observed benign gynecological disease that affects the quality of life and social psychology of women of childbearing age. However, because of the unknown etiology and incidence of adenomyosis, its pathophysiological mechanism remains unclear; further, because no noninvasive, accurate, and individualized diagnostic methods are available, treatment and efficacy evaluations are limited. Notably, the interaction between the changes in the microecological environment of the female reproductive tract and human immunity, endocrine, and other links leads to the occurrence and development of diseases. In addition, the vaginal microbiome differs in different menstrual cycles; therefore, assessing the differences between the microbiomes of patients with adenomyosis and healthy individuals in different menstrual cycles will improve the understanding of the disease and provide references for the search for noninvasive diagnosis and individualized precision treatment of adenomyosis. This study aimed to explored the data of individuals in different menstrual cycles. RESULTS: Differences in the vaginal microbiome between patients with adenomyosis and healthy individuals were observed. At phylum level, the relative abundance of Firmicutes in the adenomyosis group was higher than that in the control group, which contributed the most to the species difference between the two groups. At the genus level, Lactobacillus was the most dominant in both groups, Alpha-diversity analysis showed significant differences in the adenomyosis and control group during luteal phase (Shannon index, p = 0.0087; Simpson index, p = 0.0056). Beta-diversity index was significantly different between the two groups (p = 0.018). However, based on Weighted Unifrac analysis, significant differences were only observed throughout the luteal phase (p = 0.0146). Within the adenomyosis group, differences between women with different menstrual cycles were also observed. Finally, 50 possible biomarkers including were screened and predicted based on the random forest analyse. CONCLUSIONS: The vaginal microbiome of patients with adenomyosis and healthy individuals differed during menstrual periods, especially during the luteal phase. These findings facilitate the search for specific biological markers within a limited range and provide a more accurate, objective, and individualized diagnostic and therapeutic evaluation method for patients with adenomyosis, compared to what is currently available.

Internal and external adenomyosis phenotypes: ultrasound features and association with clinical outcomes.

STUDY QUESTION: What are the sonographic and clinical findings in women diagnosed with external and internal adenomyosis by ultrasound? SUMMARY ANSWER: Patients with external and internal adenomyosis phenotypes, diagnosed by ultrasound, present differences in sonographic features of the disease and demographic characteristics including age, parity, and association with deep endometriosis (DE) and leiomyomas. WHAT IS KNOWN ALREADY: Two different phenotypes of adenomyosis have been described based on the anatomical location of adenomyotic lesions in the myometrium, suggesting that adenomyosis affecting the inner myometrium and that affecting the external myometrial layer may have distinct origins. STUDY DESIGN, SIZE, DURATION: A cross-sectional study including 505 patients with a sonographic diagnosis of adenomyosis was performed between January 2021 and December 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women sonographically diagnosed with adenomyosis in a tertiary referral hospital that serves as a national reference center for endometriosis were included over a 2-year period. Patients were divided into two groups (internal and external adenomyosis) according to the myometrial layer affected by adenomyosis. We compared sonographic and clinical outcomes including a multivariate analysis between the two groups. MAIN RESULTS AND THE ROLE OF CHANCE: According to ultrasound findings, 353 (69.9%) patients presented with internal adenomyosis, while 152 (30.1%) presented with external adenomyosis. Women with internal adenomyosis were significantly older and less frequently nulliparous compared to those with external adenomyosis. Sonographically, internal adenomyosis appeared diffusely, it had a greater number of adenomyosis features, it presented a globular morphology of the uterus more frequently, and it coexisted with leiomyomas more frequently, compared to external adenomyosis. Conversely, the presence of translesional vascularity and associated DE were more common among the external adenomyosis group. No significant differences were found between internal and external adenomyosis groups regarding pain, heavy menstrual bleeding, spotting, or infertility. In the multivariate analysis, nulliparity, the presence of leiomyomas, and the presence of DE were independently associated with adenomyosis phenotypes (the presence of DE and nulliparity increased the risk of external adenomyosis, whereas the presence of leiomyomas was a risk factor for internal adenomyosis). Considering the impact of hormonal treatment, we found that the number of ultrasound adenomyosis criteria was significantly greater in patients without hormonal treatment. Non-treated patients more commonly presented dysmenorrhea or bleeding-associated pain and heavy menstrual bleeding than women on hormonal treatment, although there were no significant differences according to adenomyosis phenotypes. LIMITATIONS, REASONS FOR CAUTION: As the population was selected from the Endometriosis Unit of a tertiary center, there may be patient selection bias, given the high prevalence of individuals with associated endometriosis, previous endometriosis-related surgery, and/or receiving hormonal treatment. WIDER IMPLICATIONS OF THE FINDINGS: Transvaginal ultrasound is the most available and cost-effective tool for the diagnosis of adenomyosis. Adenomyosis phenotypes based on ultrasound findings may be key in achieving an accurate diagnosis and in decision-making regarding the most adequate therapeutic strategy for the management of patients with adenomyosis. Determination of the sonographic features associated with symptoms could help in the evaluation of treatment response. STUDY FUNDING/COMPETING INTEREST(S): No funding was obtained for this study and there are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Proposal for targeted, neo-evolutionary-oriented, secondary prevention of early-onset endometriosis and adenomyosis. Part I: pathogenic aspects.

The potential for repeated ovulation and menstruation is thought to have provided a Darwinian advantage during the Palaeolithic. Reproductive conditions remained relatively stable until the pre-industrial era, characterized by late menarche, very young age at first birth, multiple pregnancies, and prolonged periods of lactational amenorrhoea. For hundreds of thousands of years, menstruators experienced few ovulatory cycles, even though they were genetically adapted to ovulate and menstruate every month. In the post-industrial era, the age at menarche gradually declined, the age at first birth progressively increased, and breastfeeding became optional and often of short duration. This created a mismatch between genetic adaptation and socio-environmental evolution, so that what was initially a probable reproductive advantage subsequently contributed to increased susceptibility to diseases associated with lifetime oestrogen exposure, such as ovarian, endometrial and breast cancer and, hypothetically, also those associated with the number of ovulatory menstruations, such as endometriosis and adenomyosis. The incidence of endometriosis shows a steep and progressive increase around the age of 25 years, but given the consistently reported delay in diagnosis, the actual incidence curve should be shifted to the left, supporting the possibility that the disease has its roots in adolescence. This raises the question of whether, from an evolutionary point of view, anovulation and amenorrhoea should not still be considered the physiological state, especially in the postmenarchal period. However, an increase in the frequency of endometriosis in recent decades has not been demonstrated, although this deserves further epidemiological investigation. In addition, as endometriosis occurs in a minority of individuals exposed to retrograde menstruation, other important pathogenic factors should be scrutinised. Research should be resumed to explore in more detail the transtubal reflux of not only blood, but also endometrial cells, and whether they are systematically present in the peritoneal fluid after menstruation. If repetitive ovulatory menstruation during the early reproductive years is shown to increase the risk of endometriosis and adenomyosis development and progression in susceptible individuals, hormonal interventions could be used as secondary prevention in symptomatic adolescents.

Reduced fertility in an adenomyosis mouse model is associated with an altered immune profile in the uterus during the implantation period.

STUDY QUESTION: Does a reduction in fertility and/or systemic immune cell change occur during the early implantation period in a mouse model of adenomyosis? SUMMARY ANSWER: A reduction in fertility was observed in mice with adenomyosis, coinciding with local and systemic immune changes observed during the implantation period. WHAT IS KNOWN ALREADY: Adenomyosis is a pathology responsible for impaired fertility in humans, with a still unclear pathophysiology. One hypothesis is that changes in immune cells observed in adenomyosis-affected uteri may alter fertility, notably the physiological immune environment necessary for successful implantation and a healthy pregnancy. STUDY DESIGN, SIZE, DURATION: Randomly selected CD-1 female neonatal pups were orally dosed by administration of tamoxifen to induce adenomyosis (TAM group), while others received solvent only (control group). From 6 weeks of life, CD-1 mice of both groups were mated to study impaired fertility and related local and/or systemic immune cell changes during the early implantation period. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: To evaluate fertility and pregnancy outcomes, ultrasound imaging was performed at E (embryonic day) 7.5 and E11.5 to count the number of gestational sacs and the number of resorptions in eight mice of the TAM group and 16 mice of the control group. The mice were sacrificed at E18.5, and morphometric, functional (quantitative reverse transcription PCR; RT-qPCR), and histological analyses were performed on the placentas. To identify local and/or systemic immune changes during the early implantation period, 8 mice of the TAM group and 12 mice of the control group were sacrificed at E4.5. Uterine horns and spleens were collected for flow cytometry and RT-qPCR analyses to study the immune cell populations. To investigate the profile of the cytokines secreted during the early implantation period at the systemic level, supernatants from stimulated spleen cells were analyzed by multiplex immunoassay analysis. MAIN RESULTS AND THE ROLE OF CHANCE: By ultrasound imaging, we observed a lower number of implantation sites (P < 0.005) and a higher number of resorptions (P < 0.001) in the TAM group, leading to smaller litters (average number of fetuses per litter: 1.00 [0.00; 5.25] in the TAM group versus 12.00 [9.50; 13.75] in the control group (P < 0.001). Histological and morphometric analyses of the placentas at E18.5 showed a higher junctional/labyrinthine area ratio in the TAM group (P = 0.005). The expression levels of genes that play a role in vascularization and placental growth (Vegf (P < 0.001), Plgf (P < 0.005), Pecam (P < 0.0001), and Igf2 (P = 0.002)) were reduced in the TAM group. In the TAM group, the percentages of macrophages, natural killer (NK) cells, and dendritic cells (DC) were significantly decreased in the uterus around the implantation period. However, the number of M1 macrophages was increased. Both macrophages and DC had an increased activation profile (higher expression of MCHII, P = 0.012; CD80, P = 0.015; CCR7, P = 0.043 for macrophages, and higher expression of CD206, P = 0.018; CXCR4, P = 0.010; CCR7, P = 0.006, MCHII, P = 0.010; and CD80, P = 0.012 for DC). In spleen, an increase in the activation of macrophages (CCR7, P = 0.002; MCHII, P = 0.001; and CD80, P = 0.034) and DC was observed in the TAM group (CCR7, P = 0.001; MCHII, P = 0.001; Ly6C, P = 0.015). In the uteri and the spleen, we observed increased percentages of CD4+ T lymphocytes (P = 0.0237 and P = 0.0136, respectively) in the TAM group and, in the uteri, an increased number of regulatory T cells (P = 0.036) compared with the controls. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: This study is limited by the use of an animal model and the lack of intervention. WIDER IMPLICATIONS OF THE FINDINGS: These data support involvement of innate and adaptive immune cells in the implantation failure and the increased rate of resorption observed in the mouse model of adenomyosis. This substantiates the need for additional research in this domain, with the goal of addressing fertility challenges in women affected by this condition. STUDY FUNDING/COMPETING INTEREST(S): None.

Proposal for targeted, neo-evolutionary-oriented secondary prevention of early-onset endometriosis and adenomyosis. Part II: medical interventions.

According to consistent epidemiological data, the slope of the incidence curve of endometriosis rises rapidly and sharply around the age of 25 years. The delay in diagnosis is generally reported to be between 5 and 8 years in adult women, but it appears to be over 10 years in adolescents. If this is true, the actual onset of endometriosis in many young women would be chronologically placed in the early postmenarchal years. Ovulation and menstruation are inflammatory events that, when occurring repeatedly for years, may theoretically favour the early development of endometriosis and adenomyosis. Moreover, repeated acute dysmenorrhoea episodes after menarche may not only be an indicator of ensuing endometriosis or adenomyosis, but may also promote the transition from acute to chronic pelvic pain through central sensitization mechanisms, as well as the onset of chronic overlapping pain conditions. Therefore, secondary prevention aimed at reducing suffering, limiting lesion progression, and preserving future reproductive potential should be focused on the age group that could benefit most from the intervention, i.e. severely symptomatic adolescents. Early-onset endometriosis and adenomyosis should be promptly suspected even when physical and ultrasound findings are negative, and long-term ovulatory suppression may be established until conception seeking. As nowadays this could mean using hormonal therapies for several years, drug safety evaluation is crucial. In adolescents without recognized major contraindications to oestrogens, the use of very low-dose combined oral contraceptives is associated with a marginal increase in the individual absolute risk of thromboembolic events. Oral contraceptives containing oestradiol instead of ethinyl oestradiol may further limit such risk. Oral, subcutaneous, and intramuscular progestogens do not increase the thromboembolic risk, but may interfere with attainment of peak bone mass in young women. Levonorgestrel-releasing intra-uterine devices may be a safe alternative for adolescents, as amenorrhoea is frequently induced without suppression of the ovarian activity. With regard to oncological risk, the net effect of long-term oestrogen-progestogen combinations use is a small reduction in overall cancer risk. Whether surgery should be considered the first-line approach in young women with chronic pelvic pain symptoms seems questionable. Especially when large endometriomas or infiltrating lesions are not detected at pelvic imaging, laparoscopy should be reserved to adolescents who refuse hormonal treatments or in whom first-line medications are not effective, not tolerated, or contraindicated. Diagnostic and therapeutic algorithms, including self-reported outcome measures, for young individuals with a clinical suspicion of early-onset endometriosis or adenomyosis are proposed.

Progesterone levels do not differ between patients with or without endometriosis/adenomyosis both in those who conceive after hormone replacement therapy-frozen embryo transfer cycles and those who do not.

STUDY QUESTION: Do women with endometriosis who achieve a live birth (LB) after HRT-frozen embryo transfer (HRT-FET) have different progesterone levels on the day of transfer compared to unaffected women? SUMMARY ANSWER: In women achieving a LB after HRT-FET, serum progesterone levels on the day of the transfer did not differ between patients with endometriosis and unaffected patients. WHAT IS KNOWN ALREADY: In HRT-FET, several studies have highlighted the correlation between serum progesterone levels at the time of FET and LB rates. In the pathophysiology of endometriosis, progesterone resistance is typically described in the eutopic endometrium. This has led to the hypothesis that women with endometriosis may require higher progesterone levels to achieve a LB, especially in HRT-FET cycles without a corpus luteum. STUDY DESIGN, SIZE, DURATION: We conducted an observational cohort study at the university-based reproductive medicine center of our institution, focusing on women who underwent a single autologous frozen blastocyst transfer after HRT using exogenous estradiol and micronized vaginal progesterone for endometrial preparation between January 2019 and December 2021. Women were included only once during the study period. Serum progesterone levels were measured on the morning of the FET by a single laboratory. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were divided into groups based on whether they had endometriosis or not and whether they achieved a LB. The diagnosis of endometriosis was based on published imaging criteria (transvaginal sonography/magnetic resonance imaging) and/or confirmed histology. The primary outcome was progesterone levels on the day of the HRT-FET leading to a LB in patients with endometriosis compared to unaffected women. Subgroup analyses were performed based on the presence of deep infiltrating endometriosis or adenomyosis. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1784 patients were included. The mean age of the women was 35.1 ± 4.1 (SD) years. Five hundred and sixty women had endometriosis, while 1224 did not. About 179/560 (32.0%) with endometriosis and 381/1224 (31.2%) without endometriosis achieved a LB. Among women who achieved a LB after HRT-FET, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (13.6 ± 4.3 ng/ml vs 13.2 ± 4.4 ng/ml, respectively; P = 0.302). In the subgroup of women with deep infiltrating endometriosis (n = 142) and adenomyosis (n = 100), the mean progesterone level was 13.1 ± 4.1 ng/ml and 12.6 ± 3.7 ng/ml, respectively, with no significant difference compared to endometriosis-free patients. After adjusting for BMI, parity, duration of infertility, tobacco use, and geographic origin, neither the presence of endometriosis (coefficient 0.38; 95% CI: -0.63 to 1.40; P = 0.457) nor the presence of adenomyosis (coefficient 0.97; 95% CI: -0.24 to 2.19; P = 0.114) was associated with the progesterone level on the day of HRT-FET. Among women who did not conceive, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (P = 0.709). LIMITATIONS, REASONS FOR CAUTION: The primary limitation of our study is associated with its observational design. Extrapolating our results to other laboratories or different routes and/or dosages of administering progesterone also requires validation. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that patients diagnosed with endometriosis do not require higher progesterone levels on the day of a frozen blastocyst transfer to achieve a LB in hormonal replacement therapy cycles. STUDY FUNDING/COMPETING INTEREST(S): None declared. TRIAL REGISTRATION NUMBER: N/A.

The importance of the 'uterine factor' in recurrent pregnancy loss: a retrospective cohort study on women screened through 3D transvaginal ultrasound.

STUDY QUESTION: What is the prevalence of congenital and acquired anomalies of the uterus in women with recurrent pregnancy loss (RPL) of unknown etiology examined using 3D transvaginal ultrasound (US)? SUMMARY ANSWER: Depending on the adopted diagnostic criteria, the prevalence of partial septate uterus varies between 7% and 14% and a T-shaped uterus is 3% or 4%, while adenomyosis is 23%, at least one of type 0, type 1 or type 2 myoma is 4%, and at least one endometrial polyp is 4%. WHAT IS KNOWN ALREADY: ESHRE and the Royal College of Obstetricians and Gynaecologists guidelines on RPL recommend the adoption of the 3D transvaginal US to evaluate the 'uterine factor'. Nevertheless, there are no published studies reporting the prevalence of both congenital and acquired uterine anomalies as assessed by 3D transvaginal US and diagnosed according to the criteria proposed by the most authoritative panels of experts in a cohort of women with RPL. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study including 442 women with at least two previous first-trimester spontaneous pregnancy losses (i.e. non-viable intrauterine pregnancies), who referred to the obstetrics and gynecology unit of two university hospitals between July 2020 and July 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: Records of eligible women were reviewed. Women could be included in the study if: they were between 25 and 42 years old; they had no relevant comorbidities; they were not affected by infertility, and they had never undergone ART; they and their partner tested negative to a comprehensive RPL diagnostic work-up; and they had never undergone metroplasty, myomectomy, minimally invasive treatments for uterine fibroids or adenomyomectomy. Expert sonographers independently re-analyzed the stored 2- and 3D transvaginal US images of all included patients. Congenital uterine anomalies (CUAs) were reported according to the American Society for Reproductive Medicine (ASRM) 2021, the ESHRE/European Society for Gynaecological Endoscopy (ESGE) and the Congenital Uterine Malformation by Experts (CUME) criteria. Acquired uterine anomalies were reported according to the International Federation of Gynecology and Obstetrics (FIGO) and the Morphological Uterus Sonographic Assessment (MUSA) criteria. MAIN RESULTS AND THE ROLE OF CHANCE: The partial septate uterus was diagnosed in 60 (14%; 95% CI: 11-17%), 29 (7%; 95% CI: 5-9%), and 47 (11%; 95% CI: 8-14%) subjects, according to the ESHRE/ESGE, the ASRM 2021, and the CUME criteria, respectively. The T-shaped uterus was diagnosed in 19 women (4%; 95% CI: 3-7%) according to the ESHRE/ESGE criteria and in 13 women (3%; 95% CI: 2-5%) according to the CUME criteria. The borderline T-shaped uterus (diagnosed when two out of three CUME criteria for T-shaped uterus were met) was observed in 16 women (4%; 95% CI: 2-6%). At least one of FIGO type 0, type 1, or type 2 myoma was detected in 4% of included subjects (95% CI: 3-6%). Adenomyosis was detected in 100 women (23%; 95% CI: 19-27%) and was significantly more prevalent in women with primary RPL and in those with three or more pregnancy losses. At least one endometrial polyp was detected in 4% of enrolled women (95% CI: 3-7%). LIMITATIONS, REASONS FOR CAUTION: The absence of a control group prevented us from investigating the presence of an association between both congenital and acquired uterine anomalies and RPL. Second, the presence as well as the absence of both congenital and acquired uterine anomalies detected by 3D US was not confirmed by hysteroscopy. Finally, the results of the present study inevitably suffer from the intrinsic limitations of the adopted classification systems. WIDER IMPLICATIONS OF THE FINDINGS: The prevalence of CUAs in women with RPL varies depending on the classification system used. For reasons of clarity, the US reports should always state the name of the uterine anomaly as well as the adopted classification and diagnostic criteria. Adenomyosis seems to be associated with more severe forms of RPL. The prevalence rates estimated by our study as well as the replicability of the adopted diagnostic criteria provide a basis for the design and sample size calculation of prospective studies. STUDY FUNDING/COMPETING INTEREST(S): No specific funding was used. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Overview of crosstalk between stromal and epithelial cells in the pathogenesis of adenomyosis and shared features with deep endometriotic nodules.

Since the first description of adenomyosis more than 150 years ago, multiple hypotheses have attempted to explain its pathogenesis. Indeed, research over recent years has greatly enhanced our knowledge of the underlying causes. This has opened up avenues for the development of strategies for both disease prevention and treatment of its main symptoms, such as pelvic pain, heavy menstrual bleeding, and infertility. However, the current means are still largely ineffective, so it is vital that we shed light on the pathways involved. Dysregulated mechanisms and aberrant protein expression have been identified as contributing factors in interactions between endometrial epithelial and stromal cells, ultimately leading to the growth of adenomyotic lesions. These include collective cell migration, epithelial-to-mesenchymal transition, hormonal influence, and signaling from non-coding RNAs and extracellular vesicles. We provide a concise summary of the latest insights into the crosstalk between glands and stroma in ectopic adenomyotic lesion formation. While there is an abundance of literature on similarities between adenomyosis and deep endometriosis, there are insufficient data on the cytochemical, molecular, and pathogenetic mechanisms of these two disorders. However, various shared features, including alterations of cell adhesion molecules, abnormal hormone regulation, and the presence of cancer-driving mutations and epigenetic modifications, have been identified. Nevertheless, the pathogenic mechanisms that contribute to the cause and development of these enigmatic diseases have not been fully elucidated yet.

Improvement of early miscarriage rates in women with adenomyosis via oxytocin receptor antagonist during frozen embryo transfer-a propensity score-matched study.

BACKGROUND: Dysfunctional uterine peristalsis seems to play a pivotal role in hindering embryo implantation among women diagnosed with adenomyosis. This research aims to investigate whether administering an oxytocin receptor antagonist during a frozen embryo transfer (FET) cycle using a hormone replacement therapy (HRT) protocol can enhance in vitro fertilization (IVF) outcomes for infertile women affected by adenomyosis. METHODS: Between January 2018 and June 2022, our reproductive center conducted IVF-FET HRT cycles for infertile women diagnosed with adenomyosis. Propensity score matching was employed to select matched subjects between the two groups in a 1:1 ratio. Following this, 168 women received an oxytocin receptor antagonist during FET, constituting the study group, while the matched 168 women underwent FET without this antagonist, forming the control group. We conducted comparative analyses of baseline and cycle characteristics between the two groups, along with additional subgroup analyses. RESULTS: The study group exhibited notably lower rates of early miscarriage compared to the control group, although there were no significant differences in clinical pregnancy rates, ongoing pregnancy rates, and live birth rates between the two groups. Multivariate analysis revealed a negative correlation between the use of oxytocin receptor antagonists and early miscarriage rates in women with adenomyosis. Subgroup analyses, categorized by age, infertility types, and embryo transfer day, showed a substantial decrease in early miscarriage rates within specific subgroups: women aged ≥ 37 years, those with secondary infertility, and individuals undergoing day 3 embryo transfers in the study group compared to the control group. Furthermore, subgroup analysis based on adenomyosis types indicated significantly higher clinical pregnancy rates, ongoing pregnancy rates and live birth rates in the study group compared to the control group among women with diffuse adenomyosis. CONCLUSIONS: Administering an oxytocin receptor antagonist during FET may reduce the early miscarriage rates in women with adenomyosis.

Transcriptome analysis of adenomyosis eutopic endometrium reveals molecular mechanisms involved in adenomyosis-related implantation failure and pregnancy disorders.

BACKGROUND: Women with adenomyosis are characterized by having defective decidualization, impaired endometrial receptivity and/or embryo-maternal communication, and implantation failure. However, the molecular mechanisms underlying adenomyosis-related infertility remain unknown, mainly because of the restricted accessibility and the difficult preservation of endometrial tissue in vitro. We have recently shown that adenomyosis patient-derived endometrial organoids, maintain disease-specific features while differentiated into mid-secretory and gestational endometrial phase, overcoming these research barriers and providing a robust platform to study adenomyosis pathogenesis and the associated molecular dysregulation related to implantation and pregnancy disorders. For this reason, we aim to characterize the dysregulated mechanisms in the mid-secretory and gestational endometrium of patients with adenomyosis by RNA-sequencing. METHODS: Endometrial organoids were derived from endometrial biopsies collected in the proliferative phase of women with adenomyosis (ADENO) or healthy oocyte donors (CONTROL) (n = 15/group) and differentiated into mid-secretory (-SECorg) and gestational (-GESTorg) phases in vitro. Following RNA-sequencing, the significantly differentially expressed genes (DEGs) (FDR < 0.05) were identified and selected for subsequent functional enrichment analysis and QIAGEN Ingenuity Pathway Analysis (IPA). Statistical differences in gene expression were evaluated with the Student's t-test or Wilcoxon test. RESULTS: We identified 1,430 DEGs in ADENO-SECorg and 1,999 DEGs in ADENO-GESTorg. In ADENO-SECorg, upregulated genes included OLFM1, FXYD5, and RUNX2, which are involved in impaired endometrial receptivity and implantation failure, while downregulated genes included RRM2, SOSTDC1, and CHAC2 implicated in recurrent implantation failure. In ADENO-GESTorg, upregulated CXCL14 and CYP24A1 and downregulated PGR were related to pregnancy loss. IPA predicted a significant inhibition of ID1 signaling, histamine degradation, and activation of HMGB1 and Senescence pathways, which are related to implantation failure. Alternatively, IPA predicted an inhibition of D-myo-inositol biosynthesis and VEGF signaling, and upregulation of Rho pathway, which are related to pregnancy loss and preeclampsia. CONCLUSIONS: Identifying dysregulated molecular mechanisms in mid-secretory and gestational endometrium of adenomyosis women contributes to the understanding of adenomyosis-related implantation failure and/or pregnancy disorders revealing potential therapeutic targets. Following experimental validation of our transcriptomic and in silico findings, our differentiated adenomyosis patient-derived organoids have the potential to provide a reliable platform for drug discovery, development, and personalized drug screening for affected patients.

Magnetic Resonance Imaging-Based Classification Systems for Informing Better Outcomes of Adenomyosis After Ultrasound-Guided High-Intensity Focused Ultrasound Ablating Surgery.

BACKGROUND: A referenced MRI-based classification associated with focused ultrasound ablation surgery (FUAS) outcomes is lacking in adenomyosis. PURPOSE: To identify an MRI-based classification system for informing the FUAS outcomes. STUDY TYPE: Retrospective. POPULATION: Patients with FUAS for adenomyosis, were divided into a training set (N = 643; 355 with post-FUAS gonadotropin-releasing hormone/levonorgestrel, 288 without post-FUAS therapy) and an external validation set (N = 135; all without post-FUAS therapy). FIELD STRENGTH/SEQUENCE: 1.5 T, turbo spin-echo T2-weighted imaging and single-shot echo-planar diffusion-weighted imaging sequences. ASSESSMENT: Five MRI-based adenomyosis classifications: classification 1 (C1) (diffuse, focal, and mild), C2 (intrinsic, extrinsic, intramural, and indeterminate), C3 (internal, adenomyomas, and external), C4 (six subtypes on areas [internal or external] and volumes [<1/3 or ≥2/3]), and C5 (internal [asymmetric or symmetric], external, intramural, full thickness [asymmetric or symmetric]) for FUAS outcomes (symptom relief and recurrence). STATISTICAL TESTS: The optimal classification was significantly associated with the most subtypes of FUAS outcomes. Relating to the timing of recurrence was measured using Cox regression analysis and median recurrence time was estimated by a Kaplan-Meier curve. A P value <0.05 was considered statistically significant. RESULTS: Dysmenorrhea relief and recurrence were only associated with C2 in training patients undergoing FUAS alone. Compared with other subtypes, the extrinsic subtype of C2 was significantly associated with dysmenorrhea recurrence in the FUAS group. Besides, the median dysmenorrhea recurrence time of extrinsic subtype was significantly shorter than that of other subtypes (42.0 months vs. 50.3 months). In the validation cohort, C2 was confirmed as the optimal system and its extrinsic subtype was confirmed to have a significantly shorter dysmenorrhea recurrence time than other subtypes. DATA CONCLUSION: Classification 2 can inform dysmenorrhea relief and recurrence in patients with adenomyosis undergoing FAUS only. Itsextrinsic subtype was associated with an earlier onset of dysmenorrhea recurrence after treatment. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 5.

Correlation between endometriosis and migraine features: Results from a prospective case-control study.

BACKGROUND: Endometriosis and migraine frequently coexist, but only a limited number of studies have focused on their mutual association. The aim of our study was to investigate, in untreated women with comorbid endometriosis/adenomyosis and migraine, the correlation between headache features and endometriotic subtypes and their possible relationship with pain severity and disease disability. METHODS: Fifty women affected by endometriosis/adenomyosis and migraine matched (1:2) with 100 patients with endometriosis alone and 100 patients with only migraine were recruited and underwent pelvic ultrasound imaging and neurological examination. RESULTS: Severe adenomyosis, posterior and anterior deep infiltrating endometriosis (p = 0.027, p = 0.0031 and p = 0.029, respectively) occurred more frequently in women with migraine. Dysmenorrhea was the most commonly reported symptom in women with endometriosis and migraine and the mean VAS scores of all typical endometriotic symptoms were significantly higher in the presence of comorbidity. Women with both migraine and endometriosis reported significant higher pain intensity (p = 0.004), higher monthly migraine days (p = 0.042) and increased HIT 6-scores (p = 0.01), compared with those without endometriosis. CONCLUSIONS: Our results demonstrated that the co-occurrence of migraine in untreated women with endometriosis is associated with more severe gynecological infiltrations and correlated with increased pain intensity and disease disability.Trial Registration: Protocol number 119/21.

The adenomyosis/endometriosis IVF patient - call for clinical focus.

Endometriosis and adenomyosis are distinct clinical conditions that carry the same pathophysiological features. In recent years the clinical focus on assisted reproductive technology patients with either condition (E/A) has increased, in the recognition that this subgroup of patients might need special attention to obtain reproductive success. Endometriosis and adenomyosis are characterized by a disruption of progesterone and oestrogen signalling pathways, resulting in local oestrogen dominance and progesterone resistance at the receptor level. Recent scientific evidence suggests that the endometrial progesterone receptor resistance encountered in E/A patients can be overcome by a freeze-all policy, followed by down-regulating circulating oestradiol concentrations prior to frozen embryo transfer (FET), in combination with an increase in exogenous luteal phase progesterone supplementation in hormonal replacement therapy (HRT) FET cycles. Specifically, for adenomyosis patients who do not respond to gonadotrophin-releasing hormone agonist down-regulation in terms of a decrease in circulating oestradiol concentrations, a small case series has suggested that the addition of an aromatase inhibitor for 21 days prior to HRT-FET is a valid option. Endometriosis and adenomyosis are hormonally active diseases, which need to be treated by controlling local hyperoestrogenism and progesterone resistance. Based on physiology and recent preliminary clinical data, the authors of this opinion paper wish to stimulate discussion and spark interest in research in E/A patients.

Blockage of the NLRP3 inflammasome by MCC950 inhibits migration and invasion in adenomyosis.

RESEARCH QUESTION: Does the NOD-like receptor protein 3 (NLRP3) inflammasome have an effect in adenomyosis? DESIGN: Fresh-frozen endometrial tissues and paraffin specimens were obtained from endometrial tissues from patients with adenomyosis and controls. Western blot, quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were applied to assess expression of the NLRP3 inflammasome components. Primary eutopic endometrial stromal cells were isolated from the uteri of patients with adenomyosis. After NLRP3 was knocked down using small interfering RNA, proliferation, invasion and epithelial-mesenchymal transition (EMT) were evaluated using EdU, CCK8, transwell assays and western blot. Importantly, a mouse model of adenomyosis was established to evaluate the effects of the NLRP3 inhibitor MCC950 on the formation of adenomyosis. RESULTS: Expression of the NLRP3 inflammasome components was elevated in the ectopic or eutopic endometrium of patients with adenomyosis. NLRP3 knockdown inhibited migration, invasion and EMT in endometrial cells and primary endometrial cells (P < 0.0001). MCC950, which blocks the NLRP3 inflammasome, reduced migration and invasion of endometrial cells (P < 0.01) and primary endometrial cells (P < 0.0001) considerably. Importantly, in the mouse model of adenomyosis, MCC950 had a mitigating effect on the severity of adenomyosis (P < 0.01). CONCLUSIONS: NLRP3 was found to enhance migration, invasion and EMT of human endometrial cells in adenomyosis. Notably, the NLRP3 inhibitor MCC950 reduced migration and invasion of endometrial cells effectively. Furthermore, in the mouse model of adenomyosis, MCC950 exhibited a therapeutic effect by alleviating the severity of adenomyosis.

Oestrogen promotes the progression of adenomyosis by inhibiting CITED2 through miR-145.

RESEARCH QUESTION: Is the microRNA miR-145 involved in adenomyosis, and by what mechanisms does it affect disease development and is itself regulated? DESIGN: Fluorescence in-situ hybridization was used to observe the expression pattern of miR-145 in adenomyosis ectopic endometrium (n = 13), adenomyosis eutopic endometrium (n = 15) and non-adenomyosis eutopic endometrium (n = 14). RNA sequencing was used to screen target genes as well as downstream pathways of miR-145, which were validated by reporter gene assay, quantitative polymerase chain reaction and western blot, and further analysed using cell migration assay and chromatin immunoprecipitation assay. RESULTS: The fluorescence in-situ hybridization assay revealed a noteworthy elevation in miR-145 expression in adenomyosis tissue compared with non-adenomyosis tissue. Furthermore, RNA sequencing analysis revealed that overexpression of miR-145 resulted in heightened expression of genes associated with the cytokine signalling pathway, nucleotide-binding and oligomerization domain-like pathway and adhesion pathway, including IL-1ß and IL-6. Our study has identified CITED2 as a downstream direct target gene of miR-145, which is implicated in the inhibition of stromal cell migration induced by miR-145. Moreover, chromatin immunoprecipitation was used to validate the direct effect of oestradiol on the promoter region of miR-145, mediated by oestrogen receptor α, which facilitates the upregulation of miR-145 expression. CONCLUSION: Our findings provide evidence supporting the role of oestradiol, acting through its receptor α, in modulating the discovered miR-145-CITED2 signalling axis, thereby promoting the progression of adenomyosis.