Is the oocyte quality affected by endometriosis? A review of the literature

METTL3 deficiency leads to ovarian insufficiency due to IL-1β overexpression in theca cells

Premature ovarian insufficiency (POI) is a clinical syndrome characterised by a decline in ovarian function in women before 40 years of age and is associated with oestradiol deficiency and a complex pathogenesis. However, the aetiology of POI is still unclear and effective preventative and treatment strategies are still lacking. Methyltransferase like 3 (METTL3) is an RNA methyltransferase that is involved in spermatogenesis, oocyte development and maturation, early embryonic development, and embryonic stem cell differentiation and formation, but its role in POI is unknown. In the present study, METTL3 deficiency in follicular theca cells was found to lead to reduced fertility in female mice, with a POI-like phenotype, and METTL3 knockout promoted ovarian inflammation. Further, a reduction in METTL3 in follicular theca cells led to a decrease in the m6A modification of pri-miR-21, which further reduced pri-miR-21 recognition and binding by DGCR8 proteins, leading to a decrease in the synthesis of mature miR-21-5p. Decrease of miR-21-5p promoted the secretion of interleukin-1β (IL-1β) from follicular theca cells. Acting in a paracrine manner, IL-1β inhibited the cAMP-PKA pathway and activated the NF-κB pathway in follicular granulosa cells. This activation increased the levels of reactive oxygen species in granulosa cells, causing disturbances in the intracellular Ca2+ balance and mitochondrial damage. These cellular events ultimately led to granulosa cell apoptosis and a decrease in oestradiol synthesis, resulting in POI development. Collectively, these findings reveal how METTL3 deficiency promotes the expression and secretion of IL-1β in theca cells, which regulates ovarian functions, and proposes a new theory for the development of POI disease.

Endometriosis: recent advances that could accelerate diagnosis and improve care

Endometriosis is a common disorder associated with pain, gastrointestinal and urinary symptoms, infertility, and fatigue. It is defined by the presence of endometrial-like lesions found predominantly in the pelvis. Mechanisms that contribute to disease aetiology include changes in hormonal, inflammatory, and pain pathways. In this article, we focus on recent developments in imaging technologies, on our improved understanding of mechanisms contributing to infertility, on drug therapies that are in clinical trials, and on insights from studies on the gut that offer potential to support self-management strategies. We postulate that improvements in the quality of life of patients will be accelerated by reframing endometriosis as a multi-system disorder and learning from treatments targeting symptoms shared between endometriosis, neuroinflammatory, and gastrointestinal disorders.

[Research Progress in the Role of Mitochondrial Dysfunction in Endometriosis-Associated Infertility]

Endometriosis (EMT), a common benign gynecological disease, is a leading cause of infertility in women. EMT affects female fertility in various aspects. However, the underlying mechanisms have not been fully elucidated. Mitochondria are known as the "powerhouse" of a cell. They play pivotal roles in the physiological processes of cellular energy metabolism, calcium homeostasis, oxidative stress, autophagy, the regulation of cell cycle, and cell death, and are involved in the pathophysiology of many diseases. Cellular mitochondria are highly dynamic, continuously undergoing cyclic fission and fusion to meet the demands of cellular activities. Balanced mitochondrial dynamics are critical for maintaining normal reproductive function in women. In addition, mitochondria are the major source of reactive oxygen species (ROS). Cell damage, cell death, and fibrosis mediated by the imbalance in the oxidative-antioxidant system in EMT patients lead to decreased oocyte quality and ovarian reserve. Currently, the treatment of EMT-associated infertility remains a challenging and controversial topic. We herein reviewed the latest findings on the role of mitochondrial dysfunction in EMT-associated infertility and the potential therapeutic targets.

Endometriosis diagnosed by ultrasound is associated with lower live birth rates in women undergoing their first in vitro fertilization/intracytoplasmic sperm injection treatment

OBJECTIVE

To study the cumulative live birth rate (CLBR) after the first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment in women with or without deep-infiltrating endometriosis (DIE) and/or endometrioma diagnosed by transvaginal ultrasonography (TVUS), using the International Deep Endometriosis Analysis (IDEA) group definitions.

DESIGN

Prospective observational cohort study at a university hospital.

PATIENTS(S)

In total, 1,040 women with subfertility aged 25 to ≤39 years were undergoing their first IVF/ICSI treatment between January 2019 and October 2022. Of these, 234 (22.5%; 95% confidence interval [CI], 20.0-25.0) women were diagnosed with DIE and/or endometrioma at systematic TVUS before starting their treatment.

INTERVENTION(S)

All women underwent their first IVF or ICSI treatment. Fresh and/or frozen embryos from the first cycle were used until pregnancy was achieved or no embryos remained.

MAIN OUTCOME MEASURE(S)

Cumulative live birth rate after the first IVF/ICSI cycle in women with or without DIE and/or endometrioma.

RESULT(S)

The CLBR after the first IVF/ICSI treatment in the total cohort of women was 426/1,040 (41.0%; 95% CI, 38.0-44.0). Women with DIE and/or endometrioma had a lower CLBR (78/234, 33.3%; 95% CI, 27.3-39.4) than women without the disease (348/806, 43.2%; 95% CI, 39.8-46.6). The crude relative risk (RR) for cumulative live birth for women with DIE and/or endometrioma was 0.77; 95% CI, 0.63-0.94, and after adjustments were made for age, body mass index, s-antimüllerian hormone, stimulation protocol, and day for embryo transfer, the adjusted RR was 0.63; 95% CI, 0.48-0.82. There was no difference in the number of retrieved mature oocytes, fertilization rate, or good quality embryos between the 2 groups.

CONCLUSION

The presence of DIE and/or endometrioma diagnosed by TVUS lowers the chance of live birth in women undergoing their first IVF/ICSI treatment.

Indirect markers of oocyte quality in patients with ovarian endometriosis undergoing IVF/ICSI: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to evaluate the impact of ovarian endometriomas (OMA) on indirect markers of oocyte quality in patients undergoing IVF, compared with women without anatomical or functional ovarian abnormalities. The search spanned original randomized controlled trials, case-control studies and cohort studies published in MEDLINE, the Cochrane Controlled Trials Register and the ClinicalTrials.gov database up to October 2023. Thirty-one studies were included in the meta-analysis, showing no significant differences in fertilization (OR 1.10, 95% CI 0.94-1.30), blastulation (OR 0.86, 95% CI 0.64-1.14) and cancellation (OR 1.06, 95% CI 0.78-1.44) rates. However, patients with OMA exhibited significantly lower numbers of total and mature (metaphase II) oocytes retrieved (mean difference -1.59, 95% CI -2.25 to -0.94; mean difference -1.86, 95% CI -2.46 to -1.26, respectively), and lower numbers of top-quality embryos (mean difference -0.49, 95% CI -0.92 to -0.06). The Ovarian Sensitivity Index was similar between the groups (mean difference -1.55, 95% CI -3.27 to 0.18). The lack of data published to date prevented meta-analysis on euploidy rate. In conclusion, although the presence of OMA could decrease the oocyte yield in patients undergoing IVF/intracytoplasmic sperm injection, it does not appear to have an adverse impact on oocyte quality.

A Bizarre Case of Periovarian Hematoma in a Patient Undergoing Controlled Ovarian Stimulation Managed Conservatively

Background

The occurrence of ovarian hematoma during controlled ovarian stimulation (COS) is very rare. Until now, there is no such case reported in the literature. In this study, an attempt was made to discuss the possible mechanisms for the development of hematoma in such patients, the clinical presentation, monitoring, and management of these cases.

Case Presentation

A rare case of periovarian hematoma was reported in a patient with a history of endometriosis undergoing ovarian stimulation for in vitro fertilization. On the seventh day of stimulation, the patient complained of severe pain in the abdomen. Her vitals and blood investigations were within normal limits. On abdominal examination, mild tenderness was noted in the left iliac fossa. On vaginal examination, fullness and tenderness were noted in the left fornix. On ultrasound, probe tenderness was present and a left ovarian hematoma measuring 2.0×1.81×1.55 cm was observed. She was managed conservatively. The hematoma exhibited a gradual reduction following the pick-up procedure and eventually resolved completely within a month.

Conclusion

Underlying endometriosis could be one of the possible causes of this periovarian hematoma. A conservative approach with close monitoring forms the first-line management in hemodynamically stable patients.

Association between Uterine Adenomyosis and Infertility: Role of Axonemal Alteration in Apical Endometria

ABSTRACT

Uterine adenomyosis is an estrogen-dependent chronic inflammatory condition and may cause painful symptoms, abnormal uterine bleeding, and/or subfertility/infertility. It is characterized by the presence of endometrial glands and stroma within the myometrium causing enlargement of the uterus as a result of reactive hyperplastic and/or hypertrophic change of the surrounding myometrium. Similar to endometriosis, adenomyosis has a negative impact on female fertility. Abnormal uterotubal sperm transport, tissue inflammation, and the toxic effect of chemical mediators have been proposed as contributing factors. Inflammation-induced damage of the mucosal cilia in the fallopian tube has been reported. Besides other proposed mechanisms, our most recent study with transmission electron microscopy analysis indicated that microvilli damage and an axonemal alteration in the apical endometria occur in response to endometrial inflammation. This may be involved in the negative fertility outcome in women with adenomyosis. We present a critical analysis of the literature data concerning the mechanistic basis of infertility in women with adenomyosis and its impact on fertility outcome.

Reproductive outcome after in vitro fertilization in endometriosis - key factors and implications

Endometriosis is a benign chronic disease with a major impact on a woman's quality of life, mainly due to painful physical symptoms. Endometriosis is also a common cause of infertility caused by low ovarian reserve, distorted pelvic anatomy, and severe local inflammation with a direct negative impact on the quality of oocytes, embryos, and endometrium. We conducted a retrospective study between January 2019 and December 2023, including women with a history of surgery for endometriosis who underwent in vitro fertilization (IVF) to achieve pregnancy. Their reproductive outcome was compared with a group of patients with documented tubal obstruction. The aim of our study was to identify the factors associated with a positive impact on the pregnancy rate, specifically age, anti-Mullerian hormone (AMH), ovarian stimulation protocol, and types of gonadotropins used. We analyzed a group of 175 patients with endometriosis compared with 189 patients with tubal obstruction. The average age was similar between the two groups but with a difference in the average AMH value (1.63 ± 1.09 ng/mL vs. 2.55 ± 1.67 ng/mL). The most utilized ovarian stimulation protocol in both groups was the short gonadotropin-releasing hormone (GnRH) antagonist. The clinical pregnancy rate was 27.2% in the endometriosis group and 54.7% in the tubal obstruction group. Our study revealed that treatment with corifollitropin alfa in the endometriosis group was associated with a higher clinical pregnancy rate. AMH and age proved to be significant independent factors for the reproductive outcome.

Epidemiology of infertility in women with endometriosis

Endometriosis is a benign, chronic, inflammatory condition affecting up to 10 % of women and characterised by the presence of glands and stroma tissue outside the uterus. Epidemiological and clinical studies demonstrate a consistent association between endometriosis and infertility. However, this relationship is far to be clearly understood and several mechanisms are involved. Available data show that patients with endometriosis have an increased estimated risk of infertility between two and four times compared with the general population. On the other hand, the probability of patients with infertility to have endometriosis is reported up to about 50 % of the cases. Future studies should aim to better elucidate the mechanisms behind endometriosis-associated infertility in order to offer the more appropriate and tailored management for the patients.

Transcriptomic integrity of human oocytes used in ARTs: technical and intrinsic factor effects

BACKGROUND

Millions of children have been born throughout the world thanks to ARTs, the harmlessness of which has not yet been fully demonstrated. For years, efforts to evaluate the specific effects of ART have focused on the embryo; however, it is the oocyte quality that mainly dictates first and foremost the developmental potential of the future embryo. Ovarian stimulation, cryopreservation, and IVM are sometimes necessary steps to obtain a mature oocyte, but they could alter the appropriate expression of the oocyte genome. Additionally, it is likely that female infertility, environmental factors, and lifestyle have a significant influence on oocyte transcriptomic quality, which may interfere with the outcome of an ART attempt.

OBJECTIVE AND RATIONALE

The objective of this review is to identify transcriptomic changes in the human oocyte caused by interventions specific to ART but also intrinsic factors such as age, reproductive health issues, and lifestyle. We also provide recommendations for future good practices to be conducted when attempting ART.

SEARCH METHODS

An in-depth literature search was performed on PubMed to identify studies assessing the human oocyte transcriptome following ART interventions, or in the context of maternal aging, suboptimal lifestyle, or reproductive health issues.

OUTCOMES

ART success is susceptible to external factors, maternal aging, lifestyle factors (smoking, BMI), and infertility due to endometriosis or polycystic ovary syndrome. Indeed, all of these are likely to increase oxidative stress and alter mitochondrial processes in the foreground. Concerning ART techniques themselves, there is evidence that different ovarian stimulation regimens shape the oocyte transcriptome. The perturbation of processes related to the mitochondrion, oxidative phosphorylation, and metabolism is observed with IVM. Cryopreservation might dysregulate genes belonging to transcriptional regulation, ubiquitination, cell cycle, and oocyte growth pathways. For other ART laboratory factors such as temperature, oxygen tension, air pollution, and light, the evidence remains scarce. Focusing on genes involved in chromatin-based processes such as DNA methylation, heterochromatin modulation, histone modification, and chromatin remodeling complexes, but also genomic imprinting, we observed systematic dysregulation of such genes either after ART intervention or lifestyle exposure, as well as due to internal factors such as maternal aging and reproductive diseases. Alteration in the expression of such epigenetic regulators may be a common mechanism linked to adverse oocyte environments, explaining global transcriptomic modifications.

WIDER IMPLICATIONS

Many IVF factors and additional external factors have the potential to impair oocyte transcriptomic integrity, which might not be innocuous for the developing embryo. Fortunately, it is likely that such dysregulations can be minimized by adapting ART protocols or reducing adverse exposure.

A cohort study on IVF outcomes in infertile endometriosis patients: the effects of rapamycin treatment

RESEARCH QUESTION

Can rapamycin, used as an anti-senescence drug before IVF cycles, improve the IVF outcomes of women with endometriosis by reducing oxidative stress and senescence?

DESIGN

This retrospective analysis involved 168 endometriosis patients undergoing two successive IVF cycles. The treatment group (n = 80) received 3 months of rapamycin before the second IVF cycle, while the non-treatment group (n = 88) had no adjuvant treatment. The first and second IVF cycles were compared between and within groups. Follicular fluid from both IVF cycles (treatment group n = 28, non-treatment group n = 32) were tested for senescence-associated and oxidative stress-related markers.

RESULTS

Comparing the follicular fluid from the second cycles, the rapamycin treatment group showed decreased markers of oxidative stress (8-hydroxydesoxyguanosine, malondialdehyde) and increased antioxidant markers (superoxidase dismutase, glutathione peroxidase) (all P < 0.001); the expression of senescence-related markers p16 and p21 was also significantly lower in the treatment group than in the non-treatment group (P < 0.001). Comparing the second IVF cycles, the treatment group needed fewer days of ovarian stimulation, with increased numbers of oocytes obtained and mature oocytes compared with the non-treatment group (all P < 0.001). Furthermore, rates of fertilization, implantation and clinical pregnancy were significantly higher in the treatment group (P = 0.008, 0.034 and 0.038 respectively), as was the live birth rate (P = 0.003). No structural abnormalities were seen in fetuses born to women treated with rapamycin.

CONCLUSIONS

This study suggested an association between short-term rapamycin treatment and improved pregnancy outcomes via IVF. This result needs to be further investigated in prospective randomized controlled clinical trials.

Chronic low-grade inflammation and ovarian dysfunction in women with polycystic ovarian syndrome, endometriosis, and aging

The ovarian microenvironment is critical for follicular development and oocyte maturation. Maternal conditions, including polycystic ovary syndrome (PCOS), endometriosis, and aging, may compromise the ovarian microenvironment, follicular development, and oocyte quality. Chronic low-grade inflammation can induce oxidative stress and tissue fibrosis in the ovary. In PCOS, endometriosis, and aging, pro-inflammatory cytokine levels are often elevated in follicular fluids. In women with obesity and PCOS, hyperandrogenemia and insulin resistance induce ovarian chronic low-grade inflammation, thereby disrupting follicular development by increasing oxidative stress. In endometriosis, ovarian endometrioma-derived iron overload can induce chronic inflammation and oxidative stress, leading to ovarian ferroptosis and fibrosis. In inflammatory aging (inflammaging), senescent cells may secrete senescence-associated secretory phenotype factors, causing chronic inflammation and oxidative stress in the ovary. Therefore, controlling chronic low-grade inflammation and fibrosis in the ovary would present a novel therapeutic strategy for improving the follicular microenvironment and minimizing ovarian dysfunction.

Interleukin-22 promotes proliferation and reverses LPS-induced apoptosis and steroidogenesis attenuation in human ovarian granulosa cells: implications for polycystic ovary syndrome pathogenesis

OBJECTIVE

Interleukin 22 (IL-22) plays a role in inflammatory diseases. However, whether IL-22 affects the function of ovarian granulosa cells (GCs) and its relationship with Polycystic Ovary Syndrome (PCOS)remains unclear.

METHODS

We investigated the level of IL-22 in human follicular fluid using ELISA. The expression and localization of the IL-22 receptor 1 (IL-22R1) in GCs were investigated by RT-PCR and immunofluorescence staining, respectively. The proliferation of KGN cells (human GCs line) was assessed by CCK-8 assay and EdU assay after treatment with recombinant human IL-22 (rhIL-22) and lipopolysaccharide (LPS). Apoptosis was assessed using flow cytometry. Apoptotic proteins and steroidogenic genes were detected by western blotting.

RESULTS

ELISA's results showed that compared with the control group, PCOS patients showed lower expression of IL-22 in follicular fluid. Immunofluorescence showed that IL-22R1 is expressed and localized in human granulosa cell membranes. IL-22 promoted cell proliferation and reversed LPS-induced inhibition of cell proliferation. IL-22 alone did not affect apoptotic or steroidogenic protein expression, however, it reversed LPS-induced apoptosis via downregulation of Bcl-2, upregulation of Bax and cleaved caspase-3, and restoration of LPS-downregulated StAR, CYP11A1, and CYP19A1 expression. Western blotting confirmed that IL-22 activated the JAK2/STAT3 signaling.

CONCLUSION

IL-22 promotes cell proliferation, inhibits apoptosis, and regulates KGN cell steroidogenesis confronted with LPS, and decreased IL-22 may be involved in the development of PCOS.

Impact of moderate-to-severe endometriosis on IVF cumulative live birth rate: a retrospective matched cohort study

RESEARCH QUESTION

Does moderate-to-severe endometriosis have an impact on cumulative live birth rates (cLBR) and IVF outcomes?

DESIGN

In this retrospective matched cohort study, women with moderate-to-severe endometriosis undergoing IVF or intracytoplasmic sperm injection treatment from January 2015 to December 2020 were matched 1:2 to women with other causes of infertility (control group). The main outcome was cLBR per cycle and per woman, and secondary outcomes were number of oocytes retrieved and number of mature oocytes, fertilization rate, total number of embryos and usable embryos, implantation rate, clinical pregnancy rate and miscarriage rate per cycle.

RESULTS

In total, 195 women with endometriosis were matched with 390 women without endometriosis (323 and 646 cycles, respectively). Women with endometriosis had significantly fewer oocytes retrieved than women in the control group (P=0.003) despite higher doses of gonadotropins, but had a similar number of mature oocytes, fertilization rate, and total number of embryos and usable embryos. cLBR per cycle and per women did not differ significantly between the endometriosis group and the control group (19.8% versus 24.3%, P = 0.12; 32.3% versus 37.2%, P = 0.24, respectively). In women with endometrioma, a history of cystectomy did not impact cLBR per cycle (28.3% versus 31.9%, P = 0.68). We did not observe any significant impact of tobacco use in the endometriosis group compared with the control group (16.4% versus 25.9%, P = 0.13).

CONCLUSION

This matched cohort study did not observe a significant impact of moderate-to-severe endometriosis on cLBR among women undergoing IVF. These data are reassuring for the counselling of infertile women with endometriosis before IVF.

Laser vaporization compared with other surgical techniques in women with ovarian endometrioma: a systematic review and meta-analysis

OBJECTIVE

To compare outcomes after laparoscopic cystectomy versus laser vaporization in women of reproductive age with ovarian endometrioma.

EVIDENCE REVIEW

Our systematic review and meta-analysis was registered in PROSPERO (CRD42021281781) and was done according to the PRISMA 2020 checklist. Studies (published until October 2021) were identified by searching PubMed, Cochrane Library, Google Scholar, and ClinicalTrials.gov databases (key words "cystectomy", "laser vaporization", and "endometrioma"). The search was conducted independently by two investigators (L.P. and S.I.). Inclusion criteria were: women of reproductive age undergoing surgery for symptomatic endometriomas larger than 30 mm. The exclusion criteria were: women who undergo conservative treatment. Outcomes were: risk ratio for recurrence, ovarian reserve and pregnancy rates. The studies included were randomized clinical trials (RCTs) and nonrandomized clinical trials (prospective controlled, prospective cohort, retrospective studies, and other types of studies) that included a minimum of 10 patients and written in English. Tools recommended by the Cochrane Society achieved risk-of-bias assessment.

RESULTS

Totally, 874 studies were found, 9 studies were included in qualitative synthesis (822 patients). All the authors compared the efficacy and safety of cystectomy or laser vaporization in reproductive-aged women with ovarian endometrioma. The overall risk of bias for the randomized trials was 80% 'some concerns' and 20% 'low', and for the cohort studies, 50% 'some concerns' and 50% 'low'. The primary meta-analysis focused on recurrence rates (4 studies included) with no statistically significant differences found between these two interventions (RR = 0.53, 95% CI 0.24 to 1.21, P = 0.13). The next meta-analysis estimated antral follicle count (3 studies) which was significantly lower in cystectomy group (RR = - 2.56, 95% CI - 3.71 to - 1.42, P < 0.0001). Pregnancy rates were analyzed in 3 studies with no statistically significant difference (RR = 0.96, 95% CI 0.81 to 1.14, P = 0.64).

CONCLUSIONS

There was no statistical difference in the recurrence rate and pregnancy rates, but the antral follicle count was higher in the laser vaporization group. However, we need more clinical trials to make stronger recommendations.

Phthalate exposure and risk of ovarian dysfunction in endometriosis: human and animal data

Objective: We aimed to explore the correlations between and possible mechanisms of common environmental endocrine disruptors, phthalates, and ovarian dysfunction in endometriosis. Methods: Subjects were included in the case group (n = 107) who were diagnosed with endometriosis by postoperative pathology in Fujian Maternal and Child Hospital from February 2018 to February 2021, and the women who were excluded from endometriosis by surgery were as the control group (n = 70). The demographic information of the subjects were evaluated by questionnaire, and the clinical characteristics were evaluated by medical records and 3-year follow-up results. Gas chromatography‒mass spectrometry was used to quantify 10 metabolites of phthalates, including dimethyl ortho-phthalate (DMP), mono-n-methyl phthalate (MMP), dioctyl ortho-phthalate (DEP), mono-ethyl phthalate (MEP), di-n-butyl ortho-phthalate (DBP), mono-butyl phthalate (MBP), benzylbutyl phthalate (BBzP), mono-benzyl; phthalate (MBzP), diethylhexyl phthalate (DEHP) and mono-ethylhexyl phthalate (MEHP), in the urine samples of the subjects. Furthermore, a total of 54 SD rats were exposed to DEHP 0, 5, 50, 100, 250, 500, 1,000, 2000, and 3,000 mg/kg/day for 2 weeks. The SD rats' body weight, oestrus cycle changes, and serum anti-mullerian hormone (AMH) levels were evaluated. After sacrifice, the mass index of the rat uterus and bilateral ovaries were calculated. Finally, bioinformatics analysis of rat ovarian tissues was performed to explore the possible mechanism. SPSS 24.0 (IBM, United States) was used for data analysis. p-value <0.05 was considered statistically significant. Results: The human urinary levels of DMP (p < 0.001), MMP (p = 0.001), DEP (p = 0.003), MEP (p = 0.002), DBP (p = 0.041), MBP (p < 0.001), BBzP (p = 0.009), DEHP (p < 0.001), and MEHP (p < 0.001) were significantly higher in women with endometriosis than in controls. Notably, DEHP was a significant risk factor for endometriosis (OR: 11.0, 95% CI: 5.4-22.6). The area under the ROC curve increased when multiple phthalates were diagnosed jointly, reaching 0.974 as the highest value, which was helpful for the diagnosis of endometriosis. In vivo experiments showed that after DEHP exposure in rats, the mass index of the ovary and uterus decreased in a dose-dependent manner; the oestrus cycle of SD rats was irregularly prolonged and disordered; and the serum AMH level was negatively correlated with the DEHP exposure dose (Rho = -0.8, p < 0.001). Bioinformatics analysis of rat ovarian tissues showed that seven genes involved in the steroid biosynthesis pathway were upregulated and may play a negative role in ovarian function. Conclusion: Exposure to phthalates, especially DEHP, is associated with the occurrence of endometriosis and affects women's reproductive prognosis and ovarian function. The steroid biosynthesis pathway may be related to ovarian dysfunction. The detection of phthalate in urine may become a new biological target for the diagnosis of endometriosis.

Effect of Endometriosis on Cumulus ATP, Number of Mitochondria and Oocyte Maturity in Cumulus Oocyte Complex in Mice

OBJECTIVE

 Endometriosis causes a decrease in oocyte quality. However, this mechanism is not fully understood. The present study aimed to analyze the effect of endometriosis on cumulus cell adenosine triphosphate ATP level, the number of mitochondria, and the oocyte maturity level.

METHODS

 A true experimental study with a post-test only control group design on experimental animals. Thirty-two mice were divided into control and endometriosis groups. Cumulus oocyte complex (COC) was obtained from all groups. Adenosine triphosphate level on cumulus cells was examined using the Elisa technique, the number of mitochondria was evaluated with a confocal laser scanning microscope and the oocyte maturity level was evaluated with an inverted microscope.

RESULTS

 The ATP level of cumulus cells and the number of mitochondria in the endometriosis group increased significantly (p < 0.05; p < 0.05) while the oocyte maturity level was significantly lower (p < 0.05). There was a significant relationship between ATP level of cumulus cells and the number of mitochondrial oocyte (p < 0.01). There was no significant relationship between cumulus cell ATP level and the number of mitochondrial oocytes with oocyte maturity level (p > 0.01; p > 0.01). The ROC curve showed that the number of mitochondrial oocytes (AUC = 0.672) tended to be more accurate than cumulus cell ATP level (AUC = 0.656) in determining the oocyte maturity level.

CONCLUSION

 In endometriosis model mice, the ATP level of cumulus cells and the number of mitochondrial oocytes increased while the oocyte maturity level decreased. There was a correlation between the increase in ATP level of cumulus cells and an increase in the number of mitochondrial oocytes.

Fertility Preservation in Women with Endometriosis

Several mechanisms have been implicated in the pathogenesis of endometriosis-related infertility. For patients considering surgery, the risk of iatrogenic injury is among the most important factors in the context of fertility preservation, along with age and individual reproductive goals. In the case of endometrioma excision, evidence overwhelmingly demonstrates the negative impact of surgery on ovarian reserve, with significant reductions in antimullerian hormone (up to 30% in unilateral versus up to 44% in bilateral endometriomas). The surgical endometriosis patient should be thoroughly counseled regarding fertility preservation and discussion should include tissue, embryo, and oocyte cryopreservation options. For the latter, data support cryopreservation of 10-15 oocytes in women ≤35 years and over 20 for those >35 years for a realistic chance to achieve one or more live births. When performing surgical interventions for endometriosis, reproductive surgeons should employ fertility-conserving surgical methods to reduce the likelihood of postoperative iatrogenic diminished ovarian reserve.

Endometriosis, Oocyte, and Embryo Quality

Endometriosis is a common finding among women with infertility, and women who are diagnosed with endometriosis are almost twice as likely to experience infertility. Mechanisms by which endometriosis causes infertility remain poorly understood. In this review, we evaluate the current literature on the impact of endometriosis on oocyte and embryo quality. The presence of endometriosis evidently reduces ovarian reserve, oocyte quality, and embryo quality; however, this does not appear to translate to a clear clinical impact. Analysis of data from large assisted reproduction technology registries has shown that women with endometriosis have a lower oocyte yield but no reduction in reproductive outcomes. There is a need for future studies in the form of well-designed randomized controlled trials to further evaluate the role of surgical and medical treatment options in women with endometriosis undergoing assisted conception.

Nontargeted metabolomics analysis of follicular fluid in patients with endometriosis provides a new direction for the study of oocyte quality

Endometriosis is a common, estrogen-dependent chronic gynecological disease that endangers the reproductive system and systemic metabolism of patients. We aimed to investigate the differences in metabolic profiles in the follicular fluid between infertile patients with endometriosis and controls. A total of 25 infertile patients with endometriosis and 25 infertile controls who were similar in age, BMI, fertilization method and ovulation induction treatment were recruited in this study. Metabolomics analysis of follicular fluid was performed by two methods of high-performance liquid chromatography tandem mass spectrometry. There were 36 upregulated and 17 downregulated metabolites in the follicular fluid of patients in the endometriosis group. KEGG pathway analysis revealed that these metabolites were enriched in phenylalanine, tyrosine and tryptophan biosynthesis, aminoacyl-tRNA biosynthesis, phenylalanine metabolism and pyrimidine metabolism pathways. A biomarker panel consisting of 20 metabolites was constructed by random forest, with an accuracy of 0.946 and an AUC of 0.988. This study characterizes differences in follicular fluid metabolites and associated pathway profiles in infertile patients with endometriosis. These findings can provide a better comprehensive understanding of the disease and a new direction for the study of oocyte quality, as well as potential metabolic markers for the prognosis of endometriosis.

Current Understanding of and Future Directions for Endometriosis-Related Infertility Research with a Focus on Ferroptosis

BACKGROUND

To date, the development of therapy for endometriosis and disease-related infertility remains a major challenge. Iron overload caused by periodic bleeding is a hallmark of endometriosis. Ferroptosis is an iron- and lipid-reactive oxygen species-dependent type of programmed cell death that is distinct from apoptosis, necrosis, and autophagy. This review summarizes the current understanding of and future directions for the research and treatment of endometriosis and disease-related infertility, with the main focus on the molecular basis of ferroptosis in endometriotic and granulosa cells.

METHODS

Papers published between 2000 and 2022 in the PubMed and Google Scholar databases were included in this review.

RESULTS

Emerging evidence suggests that ferroptosis is closely linked to the pathophysiology of endometriosis. Endometriotic cells are characterized by ferroptosis resistance, whereas granulosa cells remain highly susceptible to ferroptosis, suggesting that the regulation of ferroptosis is utilized as an interventional target for research into the treatment of endometriosis and disease-related infertility. New therapeutic strategies are urgently needed to efficiently kill endometriotic cells while protecting granulosa cells.

CONCLUSIONS

An analysis of the ferroptosis pathway in in vitro, in vivo, and animal research enhances our understanding of the pathogenesis of this disease. Here, we discuss the role of ferroptosis modulators as a research approach and potential novel treatment for endometriosis and disease-related infertility.

Presence of endometrioma decreased blastocyst formation rate but not impair Assisted Reproductive Technology (ART) outcome

PURPOSE

This study aims to assess the impact of endometrioma on patients who undergo ART treatment due to endometriosis.

METHODS

A retrospective study was conducted on women ≤ 40 years of age who underwent ART treatment at an academic medical center between January 2014 and December 2020. Two-hundred-and-eight women had received IVF/ICSI treatment due to endometriosis and there were 89 patients presence of endometrioma. Patients were further divided into primary endometrioma, recurrent endometrioma and those having received cystectomy for endometrioma prior to IVF/ICSI. The control group included 624 infertile women without endometriosis.

RESULTS

In the endometrioma subgroup (B) the blastocyst formation rate was significantly lower when compared with the endometriosis (A) and control groups (C). The cumulative live birth rates (CLBRs) (60.5% versus 49.4% versus 56.9%, p = 0.194 in A versus B, p = 0.406 in A versus C, p = 0.878 in B versus C) were comparable. Multiple logistic regression analysis revealed that female age, total FSH dose and blastocyst formation rate were the significant variables in predicting CLBR (OR 0.89, CI 0.80-0.99, p < 0.025, OR 0.68 CI 0.53-0.88, p = 0.003 and OR 30.04, CI 9.93-90.9, p < 0.001, respectively). The CLBRs were comparable at 47.1%, 60% and 57.9% in the primary endometrioma, s/p cystectomy and recurrent endometrioma group.

CONCLUSION

Although the blastocyst formation rate was lower in the endometrioma group, CLBR was not worse than those who were in the endometriosis or control group. Cystectomy for endometrioma did not alter IVF/ICSI outcomes if the ovarian reserve was comparable. Recurrent endometrioma did not worsen IVF/ICSI outcomes than primary endometrioma.

Conventional IVF performs similarly in women with and without endometriosis

PURPOSE

A reduced oocyte competence has been claimed as one of the factors underlying infertility in women with endometriosis. This idea has justified the hypothesis that intracytoplasmic sperm injection (ICSI), rather than conventional IVF (c-IVF), may overcome oocyte impairment and ensure better assisted reproduction technology (ART) outcomes; however, data from the literature are controversial. Thus, the aim of this study was to compare ART success rates following (c-IVF) between women with and without endometriosis in the presence of normozoospermic partners.

METHODS

This is a retrospective, matched case-control study of 314 patients who underwent c-IVF cycles between January 2014 and December 2020. Women with endometriosis were matched in a 1:1 ratio with patients undergoing ART for other indications, considering age (± 6 months), number of oocytes retrieved (± 1), and study period. The main outcome measures included total fertilization failure, fertilization rate, embryo quality, cumulative clinical pregnancy, and live birth rates.

RESULTS

The fertilization rate and the proportion of women with total fertilization failure did not differ between women with and without endometriosis. Similarly, all other embryological variables did not also differ, except for the number of top-quality cleavage stage embryos which was higher in the endometriosis group. Cumulative clinical pregnancy and live birth rates were similar between women with and without endometriosis.

CONCLUSION

A diagnosis of endometriosis does not negatively affect the performance of c-IVF; thus, c-IVF can be efficiently used in women affected, unless a male factor is also involved. This issue holds clinical relevance to help operators on their insemination technique decision-making.

Recurrent implantation failure: A comprehensive summary from etiology to treatment

Implantation is the first step in human reproduction. Successful implantation depends on the crosstalk between embryo and endometrium. Recurrent implantation failure (RIF) is a clinical phenomenon characterized by a lack of implantation after the transfer of several embryos and disturbs approximately 10% couples undergoing in vitro fertilization and embryo transfer. Despite increasing literature on RIF, there is still no widely accepted definition or standard protocol for the diagnosis and treatment of RIF. Progress in predicting and preventing RIF has been hampered by a lack of widely accepted definitions. Most couples with RIF can become pregnant after clinical intervention. The prognosis for couples with RIF is related to maternal age. RIF can be caused by immunology, thrombophilias, endometrial receptivity, microbiome, anatomical abnormalities, male factors, and embryo aneuploidy. It is important to determine the most possible etiologies, and individualized treatment aimed at the primary cause seems to be an effective method for increasing the implantation rate. Couples with RIF require psychological support and appropriate clinical intervention. Further studies are required to evaluate diagnostic method and he effectiveness of each therapy, and guide clinical treatment.

Pattern-recognition receptors in endometriosis: A narrative review

Endometriosis is closely associated with ectopic focal inflammation and immunosuppressive microenvironment. Multiple types of pattern recognition receptors (PRRs) are present in the innate immune system, which are able to detect pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) in both intracellular and external environments. However, the exact role of PRRs in endometriosis and the underlying molecular mechanism are unclear. PRRs are necessary for the innate immune system to identify and destroy invasive foreign infectious agents. Mammals mainly have two types of microbial recognition systems. The first one consists of the membrane-bound receptors, such as toll-like receptors (TLRs), which recognize extracellular microorganisms and activate intracellular signals to stimulate immune responses. The second one consists of the intracellular PRRs, including nod-like receptors (NLRs) and antiviral proteins retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA-5) with helix enzyme domain. In this review, we mainly focus on the key role of PRRs in the pathological processes associated with endometriosis. PRRs recognize PAMPs and can distinguish pathogenic microorganisms from self, triggering receptor ligand reaction followed by the stimulation of host immune response. Activated immune response promotes the transmission of microbial infection signals to the cells. As endometriosis is characterized by dysregulated inflammation and immune response, PRRs may potentially be involved in the activation of endometriosis-associated inflammation and immune disorders. Toll-like receptor 2 (TLR2), toll-like receptor 3 (TLR3), toll-like receptor 4 (TLR4), nod-like receptor family caspase activation and recruitment domain (CARD) domain containing 5 (NLRC5), nod-like receptor family pyrin domain containing 3 (NLRP3), and c-type lectin receptors (CLRs) play essential roles in endometriosis development by regulating immune and inflammatory responses. Absent in melanoma 2 (AIM2)-like receptors (ALRs) and retinoic acid-inducible gene I-like receptors (RLRs) may be involved in the activation of endometriosis-associated immune and inflammation disorders. PRRs, especially TLRs, may serve as potential therapeutic targets for alleviating pain in endometriosis patients. PRRs and their ligands interact with the innate immune system to enhance inflammation in the stromal cells during endometriosis. Thus, targeting PRRs and their new synthetic ligands may provide new therapeutic options for treating endometriosis.

Effectiveness of gonadotrophin-releasing hormone agonist therapy to improve the outcomes of intrauterine insemination in patients suffering from stage I-II endometriosis

OBJECTIVE

To explore the role of postoperative gonadotrophin releasing hormone agonist (GnRH-a) therapy before treatment with intrauterine insemination (IUI) for infertile females with stage I-II endometriosis.

MATERIAL AND METHODS

Ninety-seven patients diagnosed with stage I-II endometriosis before IUI were enrolled in this study. The clinical pregnancy rate, cumulative pregnancy rate, live birth rate and newborn conditions were compared between the two groups with and without GnRH-a therapy.

RESULTS

The clinical pregnancy rate of IUI in the GnRH-a group was higher than that in the control group (15.29% vs. 11.82%, p = .035). By logistic regression analysis, patients treated with GnRH-a had a higher clinical pregnancy rate than those without (adjusted odds ratio (AOR) 23.190, 95% confidence interval (CI) 1.238-434.312). The live birth rate per IUI cycle in the GnRH-a group was also higher than in the controls (12.94% vs. 10%). However, the difference was not statistically significant (p = .311, AOR 4.844, 95% CI 0.229-102.320). The patients with GnRH-a therapy had a similar incidence of multiple pregnancy rate (0% vs. 0%), miscarriage rate (2.35% vs. 0.91%) and ectopic pregnancy rate (0% vs. 0.91%) as compared to the control group. The cumulative pregnancy rates were all higher in patients administered with GnRH-a than those without GnRH-a treatment in different cycles (one cycle: 17.07% vs 12.50%; two cycles: 29.27% vs 19.64%; three cycles: 31.71% vs 23.21%; ≥four cycles: 31.71% vs 23.21%), but the difference was not statistically significant. Notably, there was no more pregnancy after the third IUI cycle. The gestation weeks of delivery in the two groups were 39.09 ± 1.04 and 38.60 ± 1.17, respectively (p = .323). Nor was there difference in birth weight between the two groups (3236 ± 537 g vs 3435 ± 418 g, p = .360).

CONCLUSIONS

The administration of GnRH-a in patients with stage I-II endometriosis could be beneficial to the outcomes of IUI. It is recommended that IUI should be discontinued after three failed attempts. KEY MESSAGESEndometriosis is a common cause of infertility, but the exact mechanism remains unclear.The administration of GnRH-a before IUI treatment is beneficial for patients suffering from stage I-II endometriosis.After three failed attempts, IUI should be stopped in patients with stage I-II endometriosis.

Oocyte-Secreted Serum Biomarkers GDF9 and BMP15 in Women with Endometriosis

Oocyte-secreted growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are critical paracrine regulators of female fertility. Recent studies demonstrated that serum concentrations are associated with the number of oocytes retrieved during IVF, and therefore potential clinical use as biomarkers. However, it is unknown if the presence of endometriosis affects serum GDF9 or BMP15. An exploratory case–control study was prospectively performed on 60 women who underwent laparoscopy between April 2017 and August 2018 at two hospitals. GDF9 and BMP15 were measured by validated immunoassays in pre-operative serum samples. Data were analysed relative to laparoscopic assessment of endometriosis and staging. There were 35 women with confirmed laparoscopic diagnosis of endometriosis and 25 controls with no evidence of endometriosis at laparoscopy. GDF9 was detectable in 40% of controls and 48% of cases. There was no difference in median GDF9 concentrations between controls (20.0 pg/ml, range 20.0–2504 pg/ml) and cases (20.0 pg/ml, range 20.0–2963 pg/ml). BMP15 was detectable in 48% of controls and 58% of cases, with no difference in median concentrations between controls (26.5 pg/ml, range 24.0–1499 pg/ml) and cases (24.0 pg/ml, range 24.0–796 pg/ml). Furthermore, there were no significant differences in the proportion of detectable samples or concentrations of GDF9 or BMP15 with differing severities of endometriosis. In conclusion, serum concentrations of oocyte-secreted factors, GDF9 and BMP15 did not differ between control patients and patients with endometriosis. For clinical application in reproductive medicine, GDF9 and BMP15 serum biomarker quantitation is unlikely to be aberrant in the presence of endometriosis.

Comparison of oocyte count, fertilization, and pregnancy rates in adenomyosis patients undergoing In Vitro Fertilization with short and long protocol controlled ovarian stimulation – Restospective study

Introduction

Adenomyosis (benign gynecological disease) is an endometrial stromal tissue condition that invades the myometrium of the uterus. The administration of a gonadotropin-releasing hormone (GnRH) analog before the IVF (In Vitro Fertilization) cycle significantly increases the chances of getting pregnant in adenomyosis patient with infertile condition. There is no best protocol consensus for adenomyosis for now. This study plans to compare the outcomes of long-protocol and short-protocol of IVF in adenomyosis patients who have undergone surgery and treatment with GnRH analogs.

Method

This study is a retrospective study with a comparative method. The study was conducted at the IVF Aster Clinic and the IVF Bandung Fertility Center by reviewing retrospective data from 2015 to 2021. Patients who have been diagnosed with adenomyosis will undergo IVF procedure with a long-protocol and short-protocol pretreatment. Parameters observed were oocyte count, fertilization, and pregnancy rate.

Results

Fifty-eight patients were included. There was a significant difference in the oocytes count and the pregnancy rate in short and long groups with p value of less than 0.05, while there was no significant difference in fertilization rate with p value of greater than 0.05.

Conclusion

There were differences in the oocytes count and pregnancy rates in the short and long protocol groups in adenomyosis patients. There was no difference in fertilization rate in the short and long protocol groups in adenomyosis patients.

•

The number of oocytes and pregnancy rates were significantly difference in the short and long protocols.

•

The fertilization rates was not significantly difference in the short and long protocols.

•

Long protocols of GnRH agonists produced better effects than short protocols of GnRH antagonists, as indicated by clinical pregnancy rates (higher β-hCG levels).

Opportunities and Limits of Conventional IVF versus ICSI: It Is Time to Come off the Fence

Conventional IVF (c-IVF) is one of the most practiced assisted reproductive technology (ART) approaches used worldwide. However, in the last years, the number of c-IVF procedures has dropped dramatically in favor of intracytoplasmic sperm injection (ICSI) in cases of non-male-related infertility. In this review, we have outlined advantages and disadvantages associated with c-IVF, highlighting the essential steps governing its success, its limitations, the methodology differences among laboratories and the technical progress. In addition, we have debated recent insights into fundamental questions, including indications regarding maternal age, decreased ovarian reserve, endometriosis, autoimmunity, single oocyte retrieval-cases as well as preimplantation genetic testing cycles. The “overuse” of ICSI procedures in several clinical situations of ART has been critically discussed. These insights will provide a framework for a better understanding of opportunities associated with human c-IVF and for best practice guidelines applicability in the reproductive medicine field.

Identification of functional TF-miRNA-hub gene regulatory network associated with ovarian endometriosis

Endometriosis (EMs), one of the most common gynecological diseases, seriously affects the health and wellness of women; however, the underlying pathogenesis remains unclear. This study focused on dysregulated genes and their predicted transcription factors (TFs) and miRNAs, which may provide ideas for further mechanistic research. The microarray expression dataset GSE58178, which included six ovarian endometriosis (OE) samples and six control samples, was downloaded from the Gene Expression Omnibus (GEO) to identify differentially expressed genes (DEGs). Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to study the cellular and organism-level functions of DEGs. The protein-protein interaction (PPI) network was built and visualized using Cytoscape, and modules and hub genes were explored using various algorithms. Furthermore, we predicted miRNAs and TFs of hub genes using online databases, and constructed the TF-miRNA-hub gene network. There were 124 upregulated genes and 66 downregulated genes in EMs tissues. GO enrichment analysis showed that DEGs were concentrated in reproductive structure development and collagen-containing extracellular matrix, while KEGG pathway analysis showed that glycolysis/gluconeogenesis and central carbon metabolism in cancer require further exploration. Subsequently, HIF1A, LDHA, PGK1, TFRC, and CD9 were identified as hub genes, 22 miRNAs and 34 TFs were predicted to be upstream regulators of hub genes, and these molecules were pooled together. In addition, we found three key feedback loops in the network, MYC-miR-34a-5p-LDHA, YY1-miR-155-5p-HIF1A, and RELA-miR-93-5p-HIF1A, which may be closely related to OE development. Taken together, our study structured a TF-miRNA-hub gene network to decipher the molecular mechanism of OE, which may provide novel insights for clinical diagnosis and treatment.

Predicting success of intrauterine insemination using a clinically based scoring system

Purpose

To develop a predictive score for the success of intrauterine insemination (IUI) based on clinical parameters.

Methods

We performed a retrospective cohort study evaluating the homologous IUI cycles performed at a single university-based reproductive medical center between 2009 and 2017. The primary outcome measure was pregnancy, defined as positive serum human chorionic gonadotropin (hCG) 12–14 days after IUI. Predictive factors for pregnancy after IUI were identified, and a predictive score was developed using a multivariable continuation ratio model.

Results

Overall, 1437 IUI cycles in 758 couples were evaluated. We found a per cycle pregnancy rate of 10.9% and a cumulative pregnancy rate of 19.4%. In a multivariable analysis, the probability of pregnancy was negatively associated with female age ≥ 35 years (OR 0.63, 95% CI 0.41–0.97, p = 0.034), endometriosis, unilateral tubal factor, or anatomical alteration (OR 0.54, 95% CI 0.33–0.89, p = 0.016), anti-Mullerian hormone (AMH) < 1 ng/ml (OR 0.50, 95% CI 0.29–0.87, p = 0.014), and total progressive motile sperm count (TPMSC) < 5 mil (OR 0.47, 95% CI 0.19–0.72, p = 0.004). We developed a predictive clinical score ranging from 0 to 5. Following 3 cycles, couples in our cohort with a score of 5 had a cumulative probability of achieving pregnancy of nearly 45%. In contrast, couples with a score of 0 had a cumulative probability of only 5%.

Conclusion

IUI success rates vary widely depending on couples’ characteristics. A simple to use score could be used to estimate a couple’s chance of achieving pregnancy via IUI, facilitating individualized counseling and decision-making.

Endometriosis: A Review of Clinical Diagnosis, Treatment, and Pathogenesis

Endometriosis is a condition that affects women of reproductive age, and it is distinguished by the development of endometrial-like tissue outside the uterine cavity. It is frequently accompanied by persistent pelvic discomfort and infertility. This investigation looks into recent findings on clinical manifestation to help doctors and improve women's health. PubMed and Google Scholar were used to review on clinical diagnosis of endometriosis. The search strategy contained the terms “endometriosis” and “clinical diagnosis.” All research articles published between 1960 and 2021 were included in the search. The findings were then categorized to summarize the evidence. There was a total of 29 instances of endometriosis discovered. The patients' ages varied from 20 to 45 years old, with a median of 28.8 years and a mean of 29.4±7.7 years. Dysmenorrhea is a common disorder among adolescent girls experiencing various physical and emotional symptoms which have a detrimental influence on their quality of life. In this study, scar endometriosis was shown to be the more common variety of endometriosis, with 50% of cases predominantly developing at the lower segment cesarean section (LSCS) scar site. As a result, women with endometriosis are more likely to have miscarriages, and the quality of their embryos declines as a result.

The effect of endometriosis on fertility in an animal model

The present experimental model aimed to investigate the possible effect of endometriosis on ovarian function by altering follicular maturation and development. This single-blind, randomized study included twenty-four female Sprague Dawley mice, 2.5 months old, weighing 160-200 grams. The animals were randomly separated into four groups on the day of the surgery. Each group consisted of 6 mice. The first group (A) consisted of healthy female mice (control group). The second group (B) consisted of mice subjected to surgical insertion of ovarian endometrioma. The third group (C) consisted of mice subjected to surgically induced diffuse intraperitoneal endometriosis, and the fourth group (D) consisted of mice subjected to surgically induced extraperitoneal endometriosis. According to our experimental model, endometriosis may affect ovarian function by increasing the number of luteinized unruptured follicles (follicles that have undergone luteinization without prior rupture).

Oocyte Cryopreservation in Patients with Endometriosis: Current Knowledge and Number Needed to Treat

The rise of oocytes cryopreservation (OOC) in assisted reproductive techniques allows fertility preservation (FP) in an increasing number of indications. Endometriosis, a highly prevalent disease, potentially impairing ovarian reserve, seems, therefore, an interesting indication for it. The purpose of this study is to summarize the available evidence concerning FP by OOC in women with endometriosis and to calculate the number needed to treat (NNT). In total, 272 articles related to this topic were identified in PubMed. Eight studies were eligible for the review. In order to shed some light, a SWOT analysis was performed and the argument pros and cons were developed. The NNT calculated of OOC was 16, meaning that 16 women need to perform an OOC for one of them to have a child that she would not have had without this technique. In conclusion, OOC must be discussed with patients who suffer from endometriosis since it is an effective technique of FP, which can allow these patients to succeed a pregnancy that they otherwise would not have achieved. Nevertheless, it should not be performed in all patients as there is still a lack of robust socio-economic and risk–benefit data.

Pathogenesis of Human Adenomyosis: Current Understanding and Its Association with Infertility

The aim of this review article was to summarize our current understanding on the etiologies and pathogenesis of human adenomyosis and to clarify the relative association between adenomyosis and infertility. The exact pathogenesis of adenomyosis is still elusive. Among different reported concepts, direction invagination of gland cells from the basalis endometrium deep into myometrium is the most widely accepted opinion on the development of adenomyosis. According to this concept, endometrial epithelial cells and changed fibroblasts, abnormally found in the myometrium in response to repeated tissue injury and/or disruption at the endometrium-myometrium interface (EMI), elicit hyperplasia and hypertrophy of the surrounding smooth muscle cells. In this review, a comprehensive review was performed with a literature search using PubMed for all publications in English and Japanese (abstract in English), related to adenomyosis and infertility, from inception to April 2021. As an estrogen-regulated factor, hepatocyte growth factor (HGF) exhibits multiple functions in endometriosis, a disease commonly believed to arise from the functionalis endometrium. As a mechanistic basis of gland invagination, we investigated the role of HGF, either alone or in combination with estrogen, in the occurrence of epithelial-mesenchymal transition (EMT) in adenomyosis. Aside from microtrauma at the EMI, metaplasia of displaced Müllerian remnants, differentiation of endometrial stem/progenitor cells within the myometrium and somatic mutation of some target genes have been put forward to explain how adenomyosis develops. In addition, the possible role of microRNAs in adenomyosis is also discussed. Besides our knowledge on the conventional classification (focal and diffuse), two recently proposed classifications (intrinsic and extrinsic) of adenomyosis and the biological differences between them have been described. Although the mechanistic basis is unclear, the influence of adenomyosis on fertility outcome is important, especially considering the recent tendency to delay pregnancy among women. Besides other proposed mechanisms, a recent transmission election microscopic (TEM) study indicated that microvilli damage and an axonemal alteration in the apical endometria of human adenomyosis, in response to endometrial inflammation, may be involved in negative fertility outcomes. We present a critical analysis of the literature data concerning the mechanistic basis of infertility in women with adenomyosis and its impact on fertility outcome.

Quantitative label-free proteomic analysis of human follicle fluid to identify novel candidate protein biomarker for endometriosis-associated infertility

BACKGROUND

Endometriosis (EM) leads to a decline in fertility, which is characterized by a decrease in the number and quality of follicles, and thus has a negative impact on in vitro fertilization (IVF) outcomes. However, the mechanism of how EM affects oocytes and leads to infertility remains unclear. As a potentially available sample directly related to oocyte growth, follicular fluid (FF) has important research value. Evaluating the association of FF content and EM-associated infertility through proteomics may helpful to explore the possible pathogenesis of EM-associated infertility.

METHODS

In the present experimental study, from August 2019 to June 2020, FF samples were obtained as control group (CON-G; n = 10) from women with no one female factor of infertility and were undergoing IVF due to other reasons, 20 women with EM-associated infertility undergoing IVF with no other female factors were distributed into the EM group according to the time for IVF: (i) EM-group 1 (EM-G1, Stage I to Stage III, n = 10); (ii) EM-group 2 (EM-G2, Stage I to Stage III, n = 10). label-free quantitative proteomics (LFQP) technology and parallel reaction monitoring (PRM) approach were combined to aid in identifying and validating FF protein biomarkers for EM-associated infertility. In PRM analysis, another 20 subjects were enrolled as EM-associated infertility group (EM,Stage I to Stage III, n = 10) and controls (CON, n = 10) within the same time and inclusion criteria are the same as previously described. Finally, a potential protein biomarker panel of FF differential expressed proteins to EM-associated infertility was also evaluated by t-test and receiver operating characteristic (ROC) curve and binary Logistic regression models.

RESULTS

7 significant differential expressed proteins which closely related to EM-associated infertility were found by LFQP technology, among which immunoglobulin lambda variable 7-46 (IGLV7-46), Immunoglobulin heavy constant gamma 2 (IGHG2), glia-derived nexin (GDN) and Inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3) were significantly up-regulated (p < 0.05), while corticosteroid-binding globulin (CBG), angiotensinogen (AGT) and Fetuin-B (FETUB) were significantly down regulated (p < 0.05). Additionally, GDN and AGT was identified as a potential protein biomarker by further PRM analysis for EM-associated infertility according to ROC curve analysis and t-test (p < 0.05), the area under the curve (AUC) for GDN and AGT was 0.78 and 0.69 with optimum sensitivity of 50%, 70% and specificity of 100%, 90%, respectively. According to binary logistic regression and evaluated ROC analysis, the AUC for the combination of GDN and AGT was 0.80.

CONCLUSIONS

To the best of our knowledge, this is the first time that elevated GDN protein levels have been found in the FF of patients with EM-associated infertility. Combining LFQP technology and PRM method we found the abnormal of GDN and AGT in FF may be the potential cause of EM-associated infertility which may help to better understand the physiological and pathological mechanism of EM-associated infertility. Further experimental studies are required to confirm their mechanism in EM-associated infertility. The results of this study are also consistent with the previous conclusion that EM is a chronic inflammatory disease.

SIGNIFICANCE

To the best of our knowledge, this is the first time that elevated GDN protein levels have been found in the follicular fluid of patients with EM-associated infertility. Combining LFQP technology and PRM methods we found the abnormal of GDN and AGT protein in FF may be the potential cause of EM-associated infertility which may help to better understand the physiological and pathological mechanism of EM-associated infertility. Clinically, it has been recognized that EM is related to infertility, but the mechanism remains unclear. Our study combines label-free quantitative proteomics technology and parallel reaction monitoring methods to identify and verify the FF protein biomarkers of EM-associated infertility, which provides a good research method for follow-up research.

Iron-overloaded follicular fluid increases the risk of endometriosis-related infertility by triggering granulosa cell ferroptosis and oocyte dysmaturity

Endometriosis (EMs) occurs in approximately 50% of women with infertility. The main causes of EMs-related infertility are follicle dysplasia and reduced oocyte quality. Iron overload occurs in ovarian follicular fluid (FF) of patients with EMs, and this condition is associated with oocyte maturation disorder. However, the underlying molecular mechanism remains largely unknown. In the present study, we identified the mechanism underlying ferroptosis in ovarian granulosa cells and oocyte maturation failure in EMs based on a retrospective review of in vitro fertilization/intracytoplasmic sperm injection-frozen embryo transfer outcomes in infertile patients with EMs. Mouse granulosa cells were treated with EMs-related infertile patients' follicular fluid (EMFF) in vitro. Western blot analysis, quantitative polymerase chain reaction, fluorescence staining, and transmission electron microscopy were used to assess granulosa cells ferroptosis. The effects of exosomes were examined by nanoparticle tracking analysis, RNA-seq, and Western blot analysis. Finally, the therapeutic values of vitamin E and iron chelator (deferoxamine mesylate) in vivo were evaluated in an EMs-related infertility model. Patients with ovarian EMs experienced poorer oocyte fertility than patients with non-ovarian EMs. We observed that EMFF with iron overload-induced granulosa cell ferroptosis in vitro and in vivo. Mechanically, nuclear receptor coactivator four-dependent ferritinophagy was involved in this process. Notably, granulosa cells undergoing ferroptosis further suppressed oocyte maturation by releasing exosomes from granulosa cells. In therapeutic studies, vitamin E and iron chelators effectively alleviated EMs-related infertility models. Our study indicates a novel mechanism through which EMFF with iron overload induces ferroptosis of granulosa cells and oocyte dysmaturity in EMs-related infertility, providing a potential therapeutic strategy for EMs-related infertility.

Endometriosis: A Disease with Few Direct Treatment Options

Endometriosis is a gynecological condition characterized by the growth of endometrium-like tissues inside and outside the pelvic cavity. The evolution of the disease can lead to infertility in addition to high treatment costs. Currently, available medications are only effective in treating endometriosis-related pain; however, it is not a targeted treatment. The objective of this work is to review the characteristics of the disease, the diagnostic means and treatments available, as well as to discuss new therapeutic options.

Endometriosis and Infertility: A Long-Life Approach to Preserve Reproductive Integrity

Laparoscopic surgery was originally considered the gold standard in the treatment of endometriosis-related infertility. Assisted reproductive technology (ART) was indicated as second-line treatment or in the case of male factor. The combined approach of surgery followed by ART proved to offer higher chances of pregnancy in infertile women with endometriosis. However, it was highlighted how pelvic surgery for endometriosis, especially in cases of ovarian endometriomas, could cause iatrogenic damage due to ovarian reserve loss, adhesion formation (scarring), and ischemic damage. Furthermore, in the last few years, the trend to delay the first childbirth, recent technological advances in ultrasound diagnosis, and technological progress in clinical and laboratory aspects of ART have certainly influenced the approach to infertility and endometriosis with, ART assuming a more relevant role. Management of endometriosis should take into account that the disease is chronic and involves the reproductive system. Consequently, treatment and counselling should aim to preserve the chances of pregnancy for the patient, even if it is not associated with infertility. This review will analyse the evolution of the management of infertility associated with endometriosis and propose an algorithm for treatment decision-making based on the most recent acquisitions.

Personalized Nutrition in the Management of Female Infertility: New Insights on Chronic Low-Grade Inflammation

Increasing evidence on the significance of nutrition in reproduction is emerging from both animal and human studies, suggesting a mutual association between nutrition and female fertility. Different “fertile” dietary patterns have been studied; however, in humans, conflicting results or weak correlations are often reported, probably because of the individual variations in genome, proteome, metabolome, and microbiome and the extent of exposure to different environmental conditions. In this scenario, “precision nutrition”, namely personalized dietary patterns based on deep phenotyping and on metabolomics, microbiome, and nutrigenetics of each case, might be more efficient for infertile patients than applying a generic nutritional approach. In this review, we report on new insights into the nutritional management of infertile patients, discussing the main nutrigenetic, nutrigenomic, and microbiomic aspects that should be investigated to achieve effective personalized nutritional interventions. Specifically, we will focus on the management of low-grade chronic inflammation, which is associated with several infertility-related diseases.

Oocyte quality in assisted reproduction techniques

The metaphase II (MII) oocyte is the mature female gamete, produced from a complex maturation process called oogenesis that starts in the first weeks of embryogenesis in the female embryo tract, continues during puberty, and is completed at fertilization with the spermatozoon. Oogenesis is closely related to folliculogenesis. In assisted reproduction techniques, oocytes are retrieved in cumulus-oocyte complexes after ovarian stimulation. Before being used for in vitro fertilization or cryopreservation, the metaphase (MII) oocytes can be classified according to different morphological traits and by the presence/absence of the meiotic spindle. Except for a few and rare morphological characteristics that make the oocyte discarded, none of the morphological characteristics is predictive of oocyte competence in giving a viable embryo. On the other side, specific key performance indicators based on MII oocytes test the efficacy of in vitro treatments. Molecular, cellular, or genetic abnormalities in the oocytes have observable consequences on the embryo development dynamics and its genetic content. Besides what can be seen in vitro, several intrinsic and extrinsic factors related to the patient are responsible for the oocyte quality. The clinician and the patient herself must be aware of these factors to preserve the reproductive functions as much as possible. In the present review, we have revised oogenesis and the role of mature oocytes in supporting the fertilization process and early embryo development; we have also listed the oocyte morphological traits and key performance indicators related to the oocyte quality and studied the intrinsic and extrinsic factors that irreversibly impact female fertility.

Metformin Alleviates Endometriosis and Potentiates Endometrial Receptivity via Decreasing VEGF and MMP9 and Increasing Leukemia Inhibitor Factor and HOXA10

Background: Endometriosis affects endometrial receptivity, a key factor for successful embryo implantation. Metformin treatment is associated with alleviating the symptoms of endometriosis; however the mechanism of metformin action is unclear. Neoangiogenesis plays an important role in the development and recurrence of endometriosis. In addition, the leukemia inhibitor factor (LIF) and HOXA10 genes are also distinguishing markers of endometriosis (decrease) and endometrial receptivity (increase). This study investigated the therapeutic potentials of metformin and the underlying mechanism using an in vivo rat endometriosis model. Methods: Female Wistar albino mature rats with experimentally induced endometriosis were used in this study. Metformin was administered at doses of 100 mg/kg/d and 200 mg/kg/d. The volume of endometriotic implants was assessed. The protein and mRNA expression of the vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), the endometrial receptivity markers, LIF and HOXA10, were measured in the endometrium of rats with endometriosis. Results: Metformin treatment significantly suppressed the growth of endometriotic implants. Further, the expression of VEGF and MMP-9 protein and mRNA in endometriotic implants were significantly reduced. Metformin also significantly upregulated LIF and HOXA10 expression in endometrium from rats with endometriosis. The inhibitory effect of metformin on the growth of endometriotic implants, VEGF and MMP-9, and upregulating effect on LIF and HOXA10, was optimal at a dose of 100 mg/kg/d. Conclusion: Our in vivo data demonstrates that metformin treatment alleviates endometriosis and potentiates endometrial receptivity. The underlying mechanisms are associated with decreased expression of VEGF and MMP-9 genes and upregulation of the LIF and HOXA10 genes. The effect of metformin was optimal at 100 mg/kg/d. These findings provide a potential alternative for women with endometriosis with the potential to increase fertility. Metformin is an approved drug by FDA for diabetes and this study may add another potential clinical use for metformin.

The Experience of Fertility Preservation in a Single Tertiary Center in Korea

OBJECTIVE

Oocyte (OC), embryo (EC), and ovarian tissue cryopreservation (OTC) are options for fertility preservation (FP) before going through gonadotoxic cancer treatment, or anticipated fertility decline in benign ovarian diseases, or for planned OC. The aim of this study is to report outcomes of FP in a single tertiary hospital in Korea.

METHODS

This is a retrospective study of OC, EC, and OTC cycles. All patients who visited or were referred to the infertility clinic at the Department of Obstetrics and Gynecology for the purpose of FP between 2010 and October 2021 were included.

RESULTS

A total of 564 controlled ovarian stimulation cycles were conducted in 416 women. Three hundred fifty-seven women underwent 494 OC cycles. Most patients were diagnosed with breast cancer (22.4%), followed by endometriomas (21.9%), and then by planned OC (20.7%). Cases of OC have increased over the years, peaking at 109 cycles in 2019 compared to one in 2010. Fifty-nine women underwent 70 EC cycles, and breast cancer (50.8%) was the most common indication. Repetitive OC and EC cycles were undergone in 92 and 9 women, respectively (mean number of repetition, 1.37 and 1.19 times in OC and EC, respectively), yielding a maximum number of 33 oocytes or 23 embryos being cryopreserved per patient. The utilization rate was 3.1% (11/357) in OC and 16.9% (10/59) in EC. Twenty-six women underwent OTC, and gynecologic cancer was the most common indication (9/26, 34.6%). One woman had the cryopreserved ovarian tissue retransplanted and successfully generated embryos.

CONCLUSION

OC, EC, and OTC are possible options for preserving fertility, and these opportunities should be provided for women at risk of fertility decline or those who are eager to protect their future fertility. This is the first report on long-term FP outcomes in a single tertiary center in Korea. We expect that there will be more cases over the years and more women returning to use their gametes or embryos for pregnancy.

Molecular Signatures Correlated With Poor IVF Outcomes: Insights From the mRNA and lncRNA Expression of Endometriotic Granulosa Cells

The outcomes of in vitro fertilization (IVF) for endometriotic women are significantly worse than for patients without ovarian endometriosis (OEM), as shown by fewer retrieved oocytes. However, the exact pathophysiological mechanism is still unknown. Thus, we conducted a prospective study that analyzed mRNA and lncRNA transcriptome between granulosa cells (GCs) from patients with fewer retrieved oocytes due to OEM and GCs from controls with male factor (MF) infertility using an RNA sequencing approach. We found a group of significantly differentially expressed genes (DEGs), including NR5A2, MAP3K5, PGRMC2, PRKAR2A, DEPTOR, ITGAV, KPNB1, GPC6, EIF3A, and SMC5, which were validated to be upregulated and negatively correlated with retrieved oocyte numbers in GCs of patients with OEM, while DUSP1 demonstrated the opposite. The molecular functions of these DEGs were mainly enriched in pathways involving mitogen-activated protein kinase (MAPK) signaling, Wnt signaling, steroid hormone response, apoptosis, and cell junction. Furthermore, we performed lncRNA analysis and identified a group of differentially expressed known/novel lncRNAs that were co-expressed with the validated DEGs and correlated with retrieved oocyte numbers. Co-expression networks were constructed between the DEGs and known/novel lncRNAs. These distinctive molecular signatures uncovered in this study are involved in the pathological regulation of ovarian reserve dysfunction in OEM patients.

Dysregulated sphingolipid metabolism and autophagy in granulosa cells of women with endometriosis

We evaluated metabolic profiles between cumulus cells (CCs) and mural granulosa cells (MGCs) derived from women with endometriosis to identify their correlations with oocyte quality. CCs and MGCs were collected from women with and without endometriosis undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. The metabolomics of CCs and MGCs were measured by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) followed by a quantitative polymerase chain reaction to further confirm the genes involved in the metabolic results. LC-MS/MS analysis revealed differences in 24 metabolites of CCs and 71 metabolites of MGCs between groups. Among them, five metabolites were upregulated and 19 metabolites were downregulated in CCs with endometriosis, whereas three metabolites were upregulated and 68 metabolites were downregulated in MGCs with endometriosis. Metabolites related to sphingolipid metabolism, which included palmitic acid (PA) and docosahexaenoic acid, increased significantly only in CCs with endometriosis, whereas sphingosine and PA were significantly downregulated in MGCs with endometriosis compared with CCs and MGCs without endometriosis. Gene expression involved in ceramide synthesis (CERS1, SPTL1, and SMPD1) and autophagy (BECN1, LAMP, and PC3) were significantly higher in CCs with endometriosis according to FASN, BECN1, and LAMP protein expressions. However, gene expression involved in ceramide synthesis (SPHK1, ASAH1, and SGPP1) and autophagy (BECN1, LAMP, and PC3) were significantly lower in MGCs with endometriosis, whereas CERS1 and UGCG expression increased. There are differences in sphingolipid metabolites in CCs and MGCs with endometriosis compared with women without endometriosis. These differences seem to be involved in the regulation of autophagic cell death in preovulatory follicles.