Risk factors associated with endometriosis: importance of study population for characterizing disease in the ENDO Study

The impact of vitamin D treatment on pregnancy rate among endometriosis patients: a systematic review and meta-analysis

Background

Vitamin D supplementation is supposed to have an important role in the management of several endometriosis-related aspects, offering potential relief to affected individuals. Herein, the authors aim to evaluate the impact of vitamin D on pregnancy rates and clinical symptoms in women with endometriosis.

Methods

The authors extensively searched PubMed, Cochrane Library, EMBASE, Ovid MEDLINE, and CINAHL from their inception to 20 July 2023.

Results

Three randomized controlled trials involving 167 patients were included in this meta-analysis. The findings demonstrated that vitamin D supplementation exhibits efficacy in alleviating dysmenorrhea associated with endometriosis, as evidenced by a meta-analysis showing a significant reduction in dysmenorrhea (mean difference -1.41, 95% CI -2.61 to -0.22, P = 0.02). However, the impact on dyspareunia was inconclusive, with a non-significant mean difference of -0.2 (95% CI -1.62 to 1.22, P = 0.78). In contrast, dyschezia significantly decreased with vitamin D supplementation (mean difference -1.10, 95% CI -2.22 to 0.02, P = 0.05 However, the meta-analysis did not show a significant effect of vitamin D on chronic pelvic pain associated with endometriosis.

Conclusion

While antioxidant vitamin D supplementation demonstrates general effectiveness in alleviating endometriosis symptoms, such as dysmenorrhea, dyspareunia, and dyschezia, the existing literature lacks direct investigations into the specific impact of vitamin D on enhancing pregnancy rates among endometriosis patients. This observation prompts various hypotheses, suggesting that the positive effects of vitamin D supplementation on endometriosis-related symptoms may indirectly contribute to improved pregnancy outcomes and enhanced fertility.

Xenoestrogen concentration in women with endometriosis or leiomyomas: A case-control study

BACKGROUND

Xenoestrogens are synthetic or naturally occurring chemicals capable of altering the endocrine system of humans and animals owing to their molecular similarity to endogenous hormones. There is limited data regarding their effects on women´s health. Chronic exposure to xenoestrogens can promote the development of estrogen-related diseases.

OBJECTIVES

To examine xenoestrogen concentration (TEXB-α) differences between women with leiomyomas or endometriosis and control women, and to study the relationship between the clinical and sociodemographic characteristics of these patients and their xenoestrogen levels.

METHODS

Prospective case-control study. We selected 221 women who underwent surgery at Quironsalud Madrid University Hospital between 2017 and 2021. The cases included 117 patients: 74 women who underwent surgery for uterine leiomyomas, 21 with endometriosis, and 22 with both pathologies. The control group comprised 104 healthy women who underwent surgical procedures for other reasons. TEXB-α was determined in the omental fat of all patients. Using a questionnaire and reviewing the patients' medical records, we collected sociodemographic data and other relevant variables.

RESULTS

A significant majority of study participants (68.8%) had detectable levels of xenoestrogens. We found no association between TEXB-α levels in omental fat and the presence of myomas or endometriosis. In the case group, women living or working in Madrid Community exhibited, on average, 3.12 Eeq pM/g higher levels of TEXB-α compared to those working in other areas (p = 0.030). Women who referred to the use of estrogen-containing hormonal contraceptives had, on average, 3.02 Eeq pM/g higher levels of TEXB-α than those who had never used them (p = 0.022).

CONCLUSIONS

This study found no association between omental xenoestrogen levels and leiomyomas or endometriosis. However, their presence in most participants and their association with highly polluted areas emphasizes the importance of limiting environmental exposure to these substances. We also identified an association between hormonal contraceptive use and xenoestrogen concentration.

Association between triglyceride-glucose index and risk of endometriosis in US population: results from the national health and nutrition examination survey (1999-2006)

Background and Aims

The association of the triglyceride-glucose (TyG) index, a promising novel biomarker for insulin resistance, with the risk of endometriosis has not been investigated to date. This nationwide study aimed to explore the association between the TyG index and the endometriosis risk.

Methods

Data were obtained from the National Health and Nutrition Examination Survey (1999-2006). Female participants who provided complete data on the TyG index and endometriosis were enrolled in the analysis. Multivariate logistic regression analyses were utilized to assess the association of the TyG index with endometriosis, adjusted by multiple potential confounders. Meanwhile, in-depth subgroup analyses were conducted.

Results

A total of 1,590 eligible participants were included, among whom 135 (8.5%) women were diagnosed with endometriosis. The fully adjusted multivariate logistic model showed TyG index was significantly associated with the endometriosis risk (odds ratio [OR]Q4 versus Q1 2.04, 95% confidence interval [CI]: 1.15-3.62; P for trend=0.013). In subgroup analyses, the significantly positive association between TyG index and the risk of endometriosis was also found in parous women (ORQ4 versus Q1 2.18, 95% CI: 1.20-3.96), women without diabetes (OR Q4 versus Q1 2.12, 95% CI: 1.19-3.79), women who smoke currently (OR Q4 versus Q1 3.93, 95% CI: 1.33-11.58), women who drink currently (OR Q4 versus Q1 2.54, 95% CI: 1.27-5.07), and in women who use oral contraceptives (OR Q4 versus Q1 1.91, 95% CI: 1.04-3.51). Additionally, significantly increasing trends in the odds of endometriosis across the quartiles of the TyG index were observed in the above-mentioned subgroups (all P for trend<0.05).

Conclusions

This population-based study found that a higher TyG index, representing an increased level of insulin resistance, was associated with a higher risk of endometriosis among the US population. Our findings suggested TyG index might be a promising tool for the risk assessment of endometriosis. Prospective studies are warranted to further verify these findings.

Vitamin D and reproductive disorders: a comprehensive review with a focus on endometriosis

Vitamin D is a fat-soluble steroid hormone that was initially known only for regulating calcium and phosphorus levels and maintaining bone health. However, it was later discovered that many organs express vitamin D metabolizing enzymes and have a ligand for vitamin D, which regulates the expression of an extensive assortment of genes. As a result, vitamin D is indispensable for the proper function of organs, and its deficiency is believed to be a critical factor in symptoms and disorders such as cardiovascular diseases, autoimmune diseases, and cancers. The significance of vitamin D in reproductive tissues was recognized later, and studies have revealed its crucial role in male and female fertility, as well as proper reproductive function during pregnancy. Vitamin D deficiency has been identified as a risk factor for infertility, gonadal cancers, pregnancy complications, polycystic ovary syndrome, and endometriosis. However, data investigating the association between vitamin D levels and reproductive disorders, including endometriosis, have encountered inconsistencies. Therefore, the present study aims to review existing research on the effect of vitamin D on proper reproductive function, and the role of deficiency in reproductive diseases and specifically focuses on endometriosis.

Guideline No. 449: Diagnosis and Impact of Endometriosis - A Canadian Guideline

OBJECTIVE

To provide a contemporary approach to the understanding of the impact and methods for the diagnosis of endometriosis in Canada.

TARGET POPULATION

Individuals, families, communities, health care providers, and health care administrators who are affected by, care for patients with, or manage delivery of services for endometriosis.

OPTIONS

The diagnosis of endometriosis is facilitated by a detailed history, examination, and imaging tests with providers who are experienced in endometriosis care. Surgical evaluation with pathology confirms a diagnosis of endometriosis; however, it is not required for those whose diagnosis was confirmed with imaging.

OUTCOMES

There is a need to address earlier recognition of endometriosis to facilitate timely access to care and support. Education directed at the public, affected individuals and families, health care providers, and health care administrators are essential to reduce delays in diagnosis and treatment.

BENEFITS, HARMS, AND COSTS

Increased awareness and education about the impact and approach to diagnosis may support timely access to care for patients and families affected by endometriosis. Earlier and appropriate care may support a reduced health care system burden; however, improved clinical evaluation may require initial investments.

EVIDENCE

Each section was reviewed with a unique search strategy representative of the evidence available in the literature related to the area of focus. The literature searches for each section of this guideline are listed in Appendix A and include information from published systematic reviews described in the text.

VALIDATION METHODS

The recommendations were developed following two rounds of review by a national expert panel through an iterative 2-year consensus process. Further details on the process are shared in Appendix B. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See Appendix C (Table C1 for definitions and Table C2 for interpretations of strong and conditional recommendations).

INTENDED AUDIENCE

This guideline is intended to support health care providers and policymakers involved in the care of those impacted by endometriosis and the systems required to support them.

TWEETABLE ABSTRACT

Endometriosis impact and diagnosis updated guidelines for Canadian health care providers and policymakers.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Is endometriosis due to evolutionary maladaptation?

Similar to diabetes and unlike many pathogen-induced diseases, endometriosis is likely a result of maladaptation to the evolutionary heritage of humans. The objective of this article is to review the literature and improve understanding of the evolutionary factors behind endometriosis, leading to more effective prevention and treatment approaches. In primates, spontaneous decidualization of the endometrium evolved to ensure optimal implantation of a limited number of early embryos, unlike many non-primates which depend on early embryos to induce decidualization and subsequent pregnancy. Spontaneous decidualization results in menstrual bleeding when embryo implantation does not occur, and endometriosis is commonly believed to be caused by retrograde menstruation. Although direct evidence is lacking, it is likely that hunter-gatherer women experienced fewer menstrual periods due to pregnancy shortly after menarche, followed by repeated pregnancies and lactation. However, the mismatch between the evolved uterine physiology and rapid societal changes has led to modern women delaying pregnancy and experiencing numerous menstrual periods, potentially increasing the incidence of endometriosis. The symptoms of endometriosis are often managed by suppressing menstruation through systemic hormonal treatments, but these may have side effects. For patients with a family history of endometriosis or in the early stages of the disease, intrauterine devices releasing progesterone locally could prevent uterine bleeding and the development of endometriosis while preserving fertility and minimizing side effects.

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.

A preoperative predictive model for stage IV endometriosis

This was a retrospective study that evaluated a total of 280 patients who underwent surgery for complete removal of endometriosis to develop and validate the predictive model for stage IV endometriosis. The differences between stage I-III and stage IV endometriosis were performed by logistic regression. A model for the prediction of stage IV endometriosis was constructed, which was subsequently validated. The independent variables were visual analogue scale (VAS)≥4 [3.855, 95% confidence interval (CI): 1.675-8.871, p = 0.002], painful nodularity on uterosacral ligaments (13.954, 95% CI: 1.658-117.423, p = 0.015), and bilateral endometriosis (5.933, 95% CI: 1.931-18.225, p = 0.002). The AUC of the model was 0.777, with a sensitivity of 71.9% and specificity of 76.3% for stage IV endometriosis. Therefore, a complete collection of patient information prior to surgery, asking about pain and VAS scores, careful completion of pelvic examinations, and application of imaging techniques are conducive to better diagnosis and prediction of advanced endometriosis.IMPACT STATEMENTWhat is already known on this subject? Endometriosis, a chronic disease causing pain and infertility, is characterised by endometrial-like tissue outside the uterine cavity, which is often treated via surgery at present. Considering the risks of surgery, it is necessary to identify patients with stage IV endometriosis through non-invasive predictive models for adequate preparation for surgery. However, there is no reliable non-invasive predictive model now, despite utilisation of patient medical history, symptoms especially pain-related ones, pelvic examinations, laboratory examinations, and images in the preoperative diagnosis of endometriosis in the clinic.What do the results of this study add? A model developed based on three simple, accessible and non-invasive indicators displays good performance in predicting stage IV endometriosis.What are the implications of these findings for clinical practice and/or further research? It is conducive to diagnosing and predicting advanced endometriosis before surgery, so as to reduce the difficulty and improve the safety of surgery.

Homozygous C677T Methylenetetrahydrofolate Reductase (MTHFR) Polymorphism as a Risk Factor for Endometriosis: A Retrospective Case-Control Study

This study was conducted to evaluate the role of methylenetetrahydrofolate reductase (MTHFR) C677T homozygous polymorphism as a risk factor for endometriosis. A retrospective case-control study was conducted from January 2020 to December 2022 on all patients attending the gynecological outpatient clinic of our institution who had performed an MTHFR polymorphisms test. Patients with endometriosis were considered cases, while those without endometriosis were considered controls. The presence of an MTHFR C677T homozygous polymorphism was defined as exposure. Risk factors for endometriosis were considered confounders in a binomial logistic regression, with endometriosis diagnosis as the dependent variable. Among the 409 included patients, 106 (25.9%) cases and 303 (74.1%) controls were identified. A higher rate of MTHFR C677T homozygous polymorphism was found in patients with endometriosis (24.5% vs. 15.8%, p = 0.0453), with an adOR of 1.889 (95% CI 1.076-3.318, p = 0.0269) at the binomial logistic regression. A history of no previous pregnancy was associated with an endometriosis diagnosis (adOR 2.191, 95% CI 1.295-3.708, p = 0.0035). An MTHFR C677T homozygous polymorphism could be considered a risk factor for endometriosis. Epigenetic modifications may be the most important mechanism explaining the observed association through the processes of altered DNA methylation and reduced activity of antioxidant systems.

Diet associations in endometriosis: a critical narrative assessment with special reference to gluten

Endometriosis is characterized by the presence of endometrium-like tissue outside the uterus. The etiology remains largely unknown. Despite adequate treatment, patients can still experience symptoms or side effects resulting in therapy incompliance and in self-management strategies such as dietary measures is increasing. A gluten free diet is thought to be contributory in reducing endometriosis-related pain, thereby optimizing quality of life. However, data is conflicting and currently provides no evidence for causality. This narrative review aims to put the effect of dietary self-management strategies on endometriosis in a balanced perspective, especially the effect of gluten and a gluten free diet. Several studies have found a strong overlap in symptoms, metabolic and immune responses associated with endometriosis and those associated with celiac disease, ulcerative colitis, Crohn's disease, irritable bowel syndrome and non-celiac wheat sensitivity. However, it remains unclear whether these diseases and/or disorders are causal to an increased risk of endometriosis. Some studies have found a positive effect on the risk of endometriosis, endometriosis-related symptoms and quality of life (QoL) when women either avoided certain nutrients or foods, or applied a specific nutrient supplementation. This includes the avoidance of red meat and omega-3, an increasing intake of foods rich in anti-oxidants, micronutrients and dietary fibers (e.g., fruit, vegetables) and the appliance of a gluten free diet. However, data from the available studies were generally graded of low quality and it was noted that placebo and/or nocebo effects influenced the reported positive effects. In addition, such effects were no longer seen when adjusting for confounders such as overweight, when a translation was made from in vitro to in vivo, or when the nutrients were not supplemented as isolated sources but as part of a mixed daily diet. Finally, some studies showed that long-term adherence to a gluten free diet is often associated with an impaired diet quality and nutrient intake, leading to negative health outcomes and reduced QoL. Concluding, scientific evidence on the efficacy of dietary interventions on well-defined clinical endpoints of endometriosis is lacking and recommending a gluten free diet to women solely diagnosed with endometriosis should therefore not be advised.

Examining the co-occurrence of endometriosis and polycystic ovarian syndrome

BACKGROUND

Polycystic ovarian syndrome and endometriosis are 2 of the most common reproductive disorders among women but are thought to be unrelated.

OBJECTIVE

This study aimed to examine the overlap and common symptoms of polycystic ovarian syndrome and endometriosis.

STUDY DESIGN

The study population included the Endometriosis, Natural History, Diagnosis, and Outcomes Study (2007-2009) operative cohort: 473 women, aged 18 to 44 years, who underwent a diagnostic and/or therapeutic laparoscopy or laparotomy at 1 of 14 surgical centers located in Salt Lake City, Utah, or San Francisco, California, in addition to a population cohort composed of 127 women from the surgical centers' catchment areas. Age and site-adjusted multinomial regression models were used to estimate adjusted prevalence ratios and 95% confidence intervals of reproductive history characteristics among women with endometriosis only, women with polycystic ovarian syndrome only, and women with both endometriosis and polycystic ovarian syndrome.

RESULTS

Among the operative cohort, 35% had endometriosis only, 9% had polycystic ovarian syndrome only, and 5% had endometriosis and polycystic ovarian syndrome. Among the population cohort, 10% had endometriosis only, 8% had polycystic ovarian syndrome only, and 2% had endometriosis and polycystic ovarian syndrome. In the operative cohort, a history of subfertility was associated with a higher adjusted probability of having both conditions (adjusted prevalence ratio, 10.33; 95% confidence interval, 3.94-27.08), followed by having endometriosis only (adjusted prevalence ratio, 2.45; 95% confidence interval, 1.56-3.84) or polycystic ovarian syndrome only (adjusted prevalence ratio, 1.15; 95% confidence interval, 0.51-2.61), than having neither condition. In addition, experiencing chronic pelvic pain within the past 12 months was associated with a higher probability of having both conditions (adjusted prevalence ratio, 2.53; 95% confidence interval, 1.07-6.00) than having neither condition.

CONCLUSION

Among a cohort of women undergoing gynecologic laparoscopy or laparotomy, our study found that nearly 1 in 20 women had both an incident endometriosis diagnosis and symptoms consistent with polycystic ovarian syndrome. Among a population cohort of women not seeking gynecologic care, polycystic ovarian syndrome and endometriosis overlap prevalence was approximately 1 in 50 women.

The risk of endometriosis by early menarche is recently increased: a meta-analysis of literature published from 2000 to 2020

PURPOSE

The relationship between menarche age and endometriosis has been studied extensively; however, the results were inconsistent due to differences in study dates, populations, and methodology. The goal of this meta-analysis was to see how different research populations, dates, and types affected the estimated risk of endometriosis in early menarche.

METHODS

The terms "endometriosis", "early menarche", and other pertinent terms were searched in PubMed, Medline, and Embase. This meta-analysis comprised 16 papers published between 2000 and 2020, with a start year ranging from 1989 to 2017. Random effects were used to examine endometriosis risks in these articles. Study start years, countries, types (case-control and cohort studies), and quality (Newcastle-Ottawa scale, NOS) were all taken into account in further stratified analysis and meta-regression analyses.

RESULTS

Early menarche (< 12 years) was associated with a significant pooled risk of endometriosis with high heterogeneity (OR = 1.34, 95% CI 1.16-1.54, I² = 72.0%). Stratified analysis showed that this risk was increased in studies started after 2000 (OR = 1.62, 95% CI 0.96-1.35, I² = 74.4%), compared to those before 2000 (OR = 1.13, 95% CI 1.16-1.54, I² = 40.7%); additionally, this risk was higher in low-income countries (OR = 2.11, 95% CI 1.55-2.87, I² = 0%) than in other countries (OR = 1.25, 95% CI 1.09-1.43, I² = 70.6%). These results were further confirmed by meta-regression analysis (both P values < 0.1). No significant differences were found between different study types and NOS scores.

CONCLUSION

Our results suggested an increasing risk of endometriosis with early menarche, which was more noticeable in low-income countries. Large-scale studies are warranted.

Correlation of High-Risk Human Papilloma Virus with Deep Endometriosis: A Cross-Sectional Study

Background

Recently, it has been suggested that microbial infections play a role in the pathogenesis of endometriosis. One of the most commonly suggested infections associated with the pathogenesis of endometriosis is human papillomavirus (HPV) infection. The present study is aimed at evaluating the prevalence, types, and risk factors for HPV infection in women with endometriosis and at investigating the association of upper and lower genital tract involvement with HPV and the severity of endometriosis.

Methods

This cross-sectional study was conducted on 81 patients with endometriosis, referred to Rasool Akram Medical Complex in Tehran, Iran, for laparoscopic surgery. The patients' demographic, clinical, and anthropometric data were extracted from their medical records, as well as interviews. The stage of disease was scored based on the revised American Society for Reproductive Medicine (rASRM) classification. The HPV-positive and HPV-negative cases were compared using the chi-square test for categorical variables and Student t-test for continuous variables.

Results

Twenty (24.69%) out of 81 women with endometriosis were infected with HPV (nine cases of pelvic HPV, nine cases of vaginal HPV, and two cases of both pelvic and vaginal HPV). The HPV-infected women had a significantly lower infertility rate (15% vs. 45.9%; P = 0.014). The VAS scores for dysmenorrhea and dyspareunia were relatively the same in the two groups (P > 0.05). HPV 6 and HPV 11 were the most common types of HPV, reported in 35% and 30% of endometriosis cases, respectively.

Conclusion

The prevalence of HPV was 24.69%, and low-risk genotypes were dominant. No significant association was found between HPV and the severity of endometriosis.

Progestins in the symptomatic management of endometriosis: a meta-analysis on their effectiveness and safety

BACKGROUND

Endometriosis is a complex chronic disease that affects approximately 10% of women of reproductive age worldwide and commonly presents with pelvic pain and infertility.

METHOD & OUTCOME MEASURES

A systematic review of the literature was carried out using the databases Pubmed, Scopus, Cochrane and ClinicalTrials.gov in women with a confirmed laparoscopic diagnosis of endometriosis receiving progestins to determine a reduction in pain symptoms and the occurrence of adverse effects.

RESULTS

Eighteen studies were included in the meta-analysis. Progestins improved painful symptoms compared to placebo (SMD = -0.61, 95% CI (-0.77, -0.45), P < 0.00001) with no comparable differences between the type of progestin. After median study durations of 6-12 months, the median discontinuation rate due to adverse effects was 0.3% (range: 0 - 37.1%) with mild adverse effects reported.

CONCLUSION

The meta-analysis revealed that pain improvement significantly increased with the use of progestins with low adverse effects.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021285026.

Endometriosis diagnosis, staging and typology and adverse pregnancy outcome history

BACKGROUND

Women with endometriosis may have an increased risk of adverse pregnancy outcomes. Research has focused on infertility clinic populations limiting generalisability. Few studies report differences by endometriosis severity.

OBJECTIVES

We investigated the relationships between endometriosis diagnosis, staging and typology and pregnancy outcomes among an operative and population-based sample of women.

METHODS

Menstruating women ages 18-44 years enrolled in the ENDO Study (2007-2009), including the operative cohort: 316 gravid women undergoing laparoscopy/laparotomy at surgical centres in Utah and California; and the population cohort: 76 gravid women from the surgical centres' geographic catchment areas. Pregnancy outcomes were ascertained by questionnaire and included all pregnancies prior to study enrolment. Endometriosis was diagnosed via surgical visualisation in the operative cohort and pelvic magnetic resonance imaging in the population cohort. Adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) were estimated using generalised linear mixed models for pregnancy outcomes, adjusting for women's age at study enrolment and at pregnancy, surgical site, body mass index and lifestyle factors.

RESULTS

Women in the operative cohort with visualised endometriosis (n = 109, 34%) had a lower prevalence of live births, aPR 0.94 (95% CI 0.85, 1.03) and a higher prevalence of miscarriages, aPR 1.48 (95% CI 1.23, 1.77) compared with women without endometriosis. The direction and magnitude of estimates were similar in the population cohort. Women with deep endometriosis were 2.98-fold more likely (95% CI 1.12, 7.95) to report a miscarriage compared with women without endometriosis after adjusting for women's age at study enrolment and at pregnancy, surgical site and body mass index. No differences were seen between endometriosis staging and pregnancy outcomes.

CONCLUSIONS

While there was no difference in number of pregnancies among women with and without endometriosis in a population-based sample, pregnancy loss was more common among women with endometriosis, notably among those with deep endometriosis.

A Review of Urinary Tract Endometriosis

PURPOSE OF REVIEW

To describe the presenting signs and symptoms of patients with urinary tract endometriosis (UTE), appropriate workup, and to review medical and surgical therapies for symptom palliation and definitive management.

RECENT FINDINGS

UTE is a condition that clinicians should maintain a high index of suspicion for, as symptoms can be easily misdiagnosed from other causes. Surgical resection of implants appears to offer safe and durable symptom relief. Urinary tract endometriosis may present with symptoms overlapping with interstitial cystitis, nephrolithiasis, bladder overactivity, or recurrent urinary tract infections, and may or may not be cyclical in nature. Cyclical gross hematuria is considered pathognomonic, though final diagnosis must be made after a pathologic review. Without proper diagnosis and treatment, consequences such as silent renal loss from asymptomatic obstruction may result. After the diagnosis is made, initial therapy can be undertaken with hormonal treatment to palliate symptoms (most commonly in the form of combined oral contraceptives), followed by surgical resection for a definitive treatment option.

Identification of potential repurposed drugs for treating endometriosis-associated infertility among women

Endometriosis is the most common gynecological abnormality seen in 10-15% of women of reproductive age, causing infertility in ∼25% of cases, which calls for treatment. Thus, in this study, we have identified miRNAs and genes involved in endometriosis progression, leading to infertility, by performing gene expression analysis followed by pathway analysis and protein-protein networks study. Further, we have predicted repurposed small molecule drugs that will neutralize the regulatory effect of targeting miRNAs that induce sterility in endometriosis. This study predicted two transcription factors, FOXO1, and CREB1, targeted by miRNAs that can be modulated by the repurposed drugs, BRD-K55473186, and methylstat, respectively, for the treatment of infertility due to endometriosis. The former drug seems better and more effective than the other as it showed stronger binding at the active site of FOXO1. These findings provide the rationale for targeting miRNA-regulated transcriptional regulators controlling several biological processes to treat endometriosis and prevent the recurrence of implantation failure or infertility.

Revisiting the Risk Factors for Endometriosis: A Machine Learning Approach

Endometriosis is a condition characterized by implants of endometrial tissues into extrauterine sites, mostly within the pelvic peritoneum. The prevalence of endometriosis is under-diagnosed and is estimated to account for 5-10% of all women of reproductive age. The goal of this study was to develop a model for endometriosis based on the UK-biobank (UKB) and re-assess the contribution of known risk factors to endometriosis. We partitioned the data into those diagnosed with endometriosis (5924; ICD-10: N80) and a control group (142,723). We included over 1000 variables from the UKB covering personal information about female health, lifestyle, self-reported data, genetic variants, and medical history prior to endometriosis diagnosis. We applied machine learning algorithms to train an endometriosis prediction model. The optimal prediction was achieved with the gradient boosting algorithms of CatBoost for the data-combined model with an area under the ROC curve (ROC-AUC) of 0.81. The same results were obtained for women from a mixed ethnicity population of the UKB (7112; ICD-10: N80). We discovered that, prior to being diagnosed with endometriosis, affected women had significantly more ICD-10 diagnoses than the average unaffected woman. We used SHAP, an explainable AI tool, to estimate the marginal impact of a feature, given all other features. The informative features ranked by SHAP values included irritable bowel syndrome (IBS) and the length of the menstrual cycle. We conclude that the rich population-based retrospective data from the UKB are valuable for developing unified machine learning endometriosis models despite the limitations of missing data, noisy medical input, and participant age. The informative features of the model may improve clinical utility for endometriosis diagnosis.

Development of an endometriosis self-assessment tool for patient

Objective

This study aimed to develop and verify an endometriosis self-assessment tool (ESAT).

Methods

A non-experimental, descriptive, correlational study design was used. Candidate items were developed based on a conceptual framework constructed using the results of in-depth interviews and an integrative literature review. The construct validity of the developed tool was also examined. One-hundred and forty-two participants (117 patients with endometriosis and 25 patients without endometriosis) were included in the validity and reliability tests. The data were collected between August and December 2018. Nomological validity was verified based on significant correlations between the ESAT and the quality-of-life scores.

Results

A 21-item ESAT was developed, and its construct validity was supported. Exploratory factor analysis indicated that the tool consisted of four components (gastrointestinal symptoms, dysmenorrhea, usual symptoms, and the amount and characteristics of menstrual bleeding) with a variance of 61.6%. The variance in quality-of-life scores, as explained by the ESAT scores, was relatively high. Receiver operator characteristics curve analysis indicated that ESAT scores significantly differentiated endometriosis from non-endometriosis with fair discriminatory power at a cut-off score of 50 (sensitivity, 0.76; specificity, 0.72; area under the curve, >0.75; P<0.001). This means that patients with ESAT scores >50 points were more likely to have endometriosis. Thus, the reliability of the ESAT was confirmed.

Conclusion

The devised tool appears valid and reliable. This tool may allow women to determine their risk of endometriosis by distinguishing between normal and pathological menstruation-related symptoms.

Metabolic risk factors and fertility disorders: A narrative review of the female perspective

Metabolic risk factors such as obesity are considered major obstacles to female fertility. Chronic infertility imposes psychological and social burdens on women because infertility violates societal gender roles. Although the prevalence of obesity among women is expected to increase in the future, the relevance of metabolic status for fertility is still underestimated. However, the assessment of metabolic risk factors is highly relevant for understanding fertility disorders and improving infertility treatment. This narrative review discusses the associations of metabolic risk factors (e.g. obesity, female athlete triad, oxidative stress) with significant infertility. An electronic search was conducted for studies published between 2006 and 2020 in Cumulative Index to Nursing and Allied Health Literature, ScienceDirect, PubMed, Scopus, Google Scholar and related databases. In total, this search identified 19,309 results for polycystic ovary syndrome, 28,969 results for endometriosis, and only 1611 results for idiopathic and/or unknown infertility. For the present narrative review, 50 relevant studies were included: 19 studies were on obesity, 24 studies investigated the female athlete triad, and seven studies addressed other risk factors, including reactive oxygen species. This narrative review confirms the direct impact of obesity on female infertility, while the effect of other risk factors needs to be confirmed by large-scale population studies.

[Analysis of the factors contributing to endometriosis in China and UK]

OBJECTIVE

To explore the differences in the factors associated with endometriosis between Chinese and British patients.

METHODS

This case-control study was conducted in 387 patients with endometriosis and 199 non-endometriosis patients admitted to John Radcliffe Hospital (Oxford, UK) and in 101 patients with endometriosis and 50 non-endometriosis patients admitted in the First Affiliated Hospital of Guangzhou University of Chinese Medicine. The clinical data including height, weight, body mass index, marital status, employment, menstruation, fertility, and operation reasons were collected via a standardized WERF EPHect questionnaire.

RESULTS

Multivariate logistic regression analysis indicated that body mass index, surgery for dysmenorrhea, history of pregnancy, counts of previous surgeries for endometriosis and status of employment were all significantly associated with endometriosis in the UK (P < 0.05), while a history of dysmenorrhea was significantly correlated with endometriosis in Chinese patients (P < 0.05).

CONCLUSION

Dysmenorrhea may be the most important common factor associated with endometriosis in China and the UK, but the other factors contributing to endometriosis may differ between these two countries.

The role of dendritic cells in endometriosis: A systematic review

Endometriosis (EDT), a common estrogen-dependent inflammatory disorder, is characterized by endometrial-like tissue outside the uterus. While its pathogenesis is poorly understood, it is supposed that the immune system plays a role in its pathophysiology, and increased number of immune cells and changes in both cell-mediated and humoral immunity have been described. Dendritic cells (DCs) are antigen-presenting cells (APC) of the immune system that recognize, capture, and process complex antigens and present them to T cells, conferring them a unique ability as mediators between the innate and adaptive immune systems. This systematic review aims to enlighten possible disturbances (systemically and locally) of DCs in the development and progression of endometriosis. A search using the strategy: ("dendritic cells" AND "immunology" AND "endometriosis") in databases resulted in 490 citations; after applying inclusion and exclusion criteria, a total of 13 studies were assessed. The evaluated studies demonstrated that DCs are susceptible to pro-endometriotic changes which could inhibit immature DCs (imDCs) from their maturation and induce imDCs into a macrophage phenotype. In addition, the growth and vascularization of endometriosis requires the presence of endogenous DC, which infiltrate endometriotic lesions and enhance endothelial cell migration by secreting proangiogenic factors. Whereas DC maturation suppresses this response, imDC actively promote angiogenesis and growth, leading to a switch in their immunologic role from presenting antigens to support angiogenesis and EDT progression.

Perfluoroalkyl substances (PFAS) in drinking water and risk for polycystic ovarian syndrome, uterine leiomyoma, and endometriosis: A Swedish cohort study

BACKGROUND

Perfluorinated substances (PFAS) are chemicals with endocrine disruptive properties that may interfere with the female reproductive system. However, few studies have explored the association between benign gynecological diseases and high PFAS exposure.

OBJECTIVES

The aim of this study was to investigate the possible associations between PFAS exposure and subsequent diagnosis of polycystic ovarian syndrome (PCOS), uterine leiomyoma (fibroids), and endometriosis in a cohort exposed to PFAS through drinking water.

MATERIAL AND METHODS

In 2013, high levels (with sum of PFAS above 10,000 ng/L), dominated by perfluorooctanesulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS), were found in the drinking water from one of the two waterworks in Ronneby, Sweden. The contamination came from firefighting foams used at a nearby airfield. Females of all ages (n = 29,106) who had ever resided in the municipality between 1985 and 2013 formed a cohort. Individual exposure was assessed based on municipality waterworks distribution data linked to annual residential address data; 27% of the females had ever lived at an address with PFAS-contaminated water. Gynecological health outcomes were retrieved from the Swedish National Patient Register. The Cox proportional hazards model was used to estimate the association between exposure and each diagnosis.

RESULTS

There were in all 161 cases of PCOS, 1,122 cases of uterine leiomyoma, and 373 cases of endometriosis. In women aged 20-50 years (n = 18,503), those with the highest estimated PFAS exposure had increased hazard ratios (HR) for PCOS (HR = 2.18; 95% confidence interval (CI) 1.43, 3.34) and uterine leiomyoma (HR = 1.28; 95% CI 0.95, 1.74). No increased HR for endometriosis was found (HR = 0.74; 95% CI 0.42, 1.29).

CONCLUSIONS

Exposure to high levels of PFAS in drinking water was associated with increased risk of PCOS and possibly uterine leiomyoma, but not endometriosis. The findings for PCOS are consistent with prior studies reporting positive associations between PCOS and PFAS exposure at background levels.

Detection of Persistent Organic Pollutants in Omental Adipose Tissue from Patients with Diffuse-Gastric Cancer: A Pilot Study

Simple Summary

This pilot study reported the observation that great omentum could be analyzed to detect persistent organic pollutants (POPs). Diffuse gastric cancer is an increasing disease that could be associated with pollutants’ exposition. Here, we report a specific POP profile regarding a patient not affected by cancer, nor by diffuse gastric cancer or other abdominal cancers. The widespread presence of a substantial list of POPs (PCDDs/Fs, PCBs, and brominated flame retardants) was found in the omentum from patients with diffuse gastric cancer with minor presence of some organochlorine pesticides.

Abstract

The greater omentum represents a specific adipose tissue resected with gastric surgery for cancer. Diffuse gastric adenocarcinoma (diffuse-GC) is of major relevance among gastric cancers due to its unknown origin, aggressiveness, and metastasis in the peritoneal cavity. We postulated that persistent organic pollutants (POPs) could be detected in the greater omentum. Great omentum from patients with (i) diffuse-GC, or (ii) with other peritoneal metastatic cancer, and (iii) control group without cancer disease were analyzed for the distribution of a large panel of 96 POPs. POPs include polychlorinated dioxins/furans (PCDD/Fs), polychlorobiphenyls (PCBs), polybrominated diphenyl ethers (PBDE), polybrominated biphenyls (PBB), hexabromocyclododecanes, organochlorine pesticides, and polycyclic aromatic hydrocarbons (PAHs). The widespread presence of a substantial list of POPs (PCDDs/Fs, PCBs, and brominated flame retardants) was found in the omentum from patients with aggressive diffuse-GC, with minor presence of some organochlorine pesticides and PAHs at the low analyzed levels. Some chemicals appeared in larger concentrations in diffuse-GC or other cancer groups, including some PCDDs, PCB105, 123, 138, PBDE209, and PBB153. Overall, the present pilot study provides novel information regarding POPs levels in the omental fat, which is an understudied fat depot in terms of POPs load, and diffuse-GC association.

Endometrial microbiota is more diverse in people with endometriosis than symptomatic controls

Endometriosis is a chronic, estrogen-dependent gynecological condition affecting approximately 10% of reproductive age women. The most widely accepted theory of its etiology includes retrograde menstruation. Recent reports suggest the uterus is not sterile. Thus, the refluxed menstrual effluent may carry bacteria, and contribute to inflammation, the establishment and growth of endometriotic lesions. Here, we compared and contrasted uterine bacteria (endometrial microbiota) in people with surgically confirmed presence (N = 12) or absence of endometriosis (N = 9) using next-generation 16S rRNA gene sequencing. We obtained an average of > 9000 sequence reads per endometrial biopsy, and found the endometrial microbiota of people with endometriosis was more diverse (greater Shannon Diversity Index and proportion of 'Other' taxa) than symptomatic controls (with pelvic pain, surgically confirmed absence of endometriosis; diagnosed with other benign gynecological conditions). The relative abundance of bacterial taxa enriched in the endometrial microbiota of people with endometriosis belonged to the Actinobacteria phylum (Gram-positive), Oxalobacteraceae (Gram-negative) and Streptococcaceae (Gram-positive) families, and Tepidimonas (Gram-negative) genus, while those enriched in the symptomatic controls belonged to the Burkholderiaceae (Gram-negative) family, and Ralstonia (Gram-negative) genus. Taken together, results suggest the endometrial microbiota is perturbed in people with endometriosis.

Decreased occurrence of endometriosis in women with Chlamydia trachomatis infection

PROBLEM

Despite abundant reports on the risk role of uterine outflow tract obstruction in endometriosis, information on the occurrence of endometriosis in women with Chlamydia trachomatis infection causing fallopian tube obstruction is unknown. We investigated the role of Chlamydia trachomatis infection with or without fallopian tubal patency in the occurrence of endometriosis.

METHODS

This is a retrospective case-controlled cohort study with 539 women who had laparoscopic surgery for several indications during the period between January, 2003 and June, 2010. Women with ectopic pregnancy, uterine anomaly, chromosomal abnormality, primary amenorrhea, and perimenopausal women were excluded. Endometriosis was diagnosed by laparoscopic inspection and confirmed by histopathology. Tubal patency was diagnosed by HSG or laparoscopic chromopertubation test. Presence of chlamydia infection was examined by RT-PCR and serological test.

RESULTS

Two-hundred and seven women were enrolled. Eighty-six (41.5%) women had chlamydia infection. Tubal patency and occurrence of endometriosis were significantly decreased among women with chlamydia infection comparing to women without it (P = .005 and P = .0008, respectively). Even among women with patent tube, laparoscopic detection of endometriosis was significantly decreased in chlamydia infected comparing to non-infected women (P = .02). Multiple logistic regression model revealed that previous history of chlamydia infection significantly decreased the occurrence of endometriosis, and was independent of age, menstrual status, parity and tubal patency (odds ratio .44; 95% confidence interval .24-.80; P = .007).

CONCLUSION

A decreased occurrence of peritoneal endometriosis was observed in women with Chlamydia trachomatis infection. The possible impairment of retrograde menstrual flow by chlamydia-infected tubal damage may decrease the risk of endometriosis.

Uterine leiomyoma is associated with the risk of developing endometriosis: A nationwide cohort study involving 156,195 women

Objective

Evidence for an association between uterine leiomyoma and increased risk of endometriosis is limited by small sample sizes and short follow-up periods. We assessed this association in a large nationwide sample with 14 years of data.

Design

Data were sourced from Taiwan’s Longitudinal Health Insurance Database 2000 (LHID2000).

Materials and methods

We identified 31,239 women aged ≥20 years diagnosed with uterine leiomyoma (International Classification of Disease, Ninth Revision, Clinical Modification [ICD-9-CM] code 218) between Jan 1, 2000 and Dec 31, 2012, who were matched with 124,956 controls (1:4) by 5-year age groups and year of diagnosis. Follow-up was from the date of LHID2000 entry to the first occurrence of endometriosis, loss to follow-up, insurance termination, or until December 31, 2013, whichever was earlier.

Results

In Cox regression analysis, the adjusted hazard ratio (aHR) for endometriosis in women with uterine leiomyoma was 6.44 (95% CI, 6.18, 6.72) compared with controls. The risk of endometriosis was significantly increased in women with uterine leiomyoma and comorbidities of tube-ovarian infection (aHR 2.86; 95% CI, 1.28, 6.36), endometritis (1.14; 1.06, 1.24), infertility (1.26; 1.16, 1.37), or allergic diseases (1.11; 1.05, 1.17). Having both uterine leiomyoma and endometritis significantly increased the risk of endometriosis (aHR 6.73; 95% CI, 6.07, 7.45) versus having only uterine leiomyoma (6.61; 6.33, 6.91) or endometritis (1.49; 1.31, 1.69). Similarly, having both uterine leiomyoma and infertility significantly increased the risk of endometriosis (aHR 6.95; 95% CI, 6.21, 7.78) versus having only uterine leiomyoma (6.66; 6.38, 6.96) or infertility (1.78; 1.57, 2.02).

Conclusions

A diagnosis of uterine leiomyoma appears to increase the risk of endometriosis. Patients presenting with uterine fibroids should be encouraged to give informed consent for possible simultaneous surgical treatment of endometriosis.

Clinical Features and Long-Term Outcomes After Laparoscopic Surgery in Patients Co-existing With Endometriosis and Adenomyosis

Objective: To investigate the difference of clinical features and outcomes between EM patients with and without AM after following up for at least 6 years after surgery.

Methods: We retrospectively analyzed 358 EM patients who had a minimum of 6 years follow-up after laparoscopic cystectomy, which was performed by one single doctor at Peking Union Medical College Hospital from January 2009 to April 2013. All women were divided into AM group and non-AM group and analysis was performed in preoperative characteristics, surgical findings and postoperative outcomes during follow-up.

Results: A total of 358 EM patients were recruited, of which 142 (39.7%) were in the AM group and the rest 216 (60.3%) in the non-AM group. Between the two group, the mean age was 34.6 vs. 32.2 years (P < 0.001). The mean operating time in the AM and non-AM group was 73.2 vs. 61.9 min (P < 0.001). According to the revised AFS classification, the mean score of the two group were 60.3 vs. 45.5 (P < 0.001). At the end of the follow-up, though the AM group was with higher rate of disease relapse, yet no significant difference was found between the two groups in statistical comparison (34/142 [23.9%] vs. 34/216 [15.7%], P = 0.053). With a minimum follow-up of 6 years after laparoscopic cystectomy, failed and successful pregnancy were seen in 107/142(75.4%) and 35/142 (24.6%) patients in the AM group vs. 114/216(52.8%) and 102/216 (47.2%) patients in the non-AM group (P < 0.05). As for the successfully pregnant patients, live births, including spontaneous pregnancy and IVF-ET, were seen in 34/35 (97.1) vs. 99/102 (97.1) patients between AM and non-AM groups, while others ended in spontaneous abortion. No significant associations were found between the two groups in infertility, leiomyoma presence, the size of ovarian endometrioma, type of deep infiltrating endometriosis (DIE) or type of recurrence (P > 0.05).

Conclusion: Compared with non-AM group, EM patients with concurrent AM may have higher age, longer mean operating time and higher mean AFS score. In terms of fertility outcomes, patients in the AM group were with lower likelihood of pregnancy after surgery during the long-time follow-up.

Activation of Hypocretin Neurons in Endometriosis

Endometriosis is a gynecological disease affecting 6-10% of women of reproductive age. In addition to gynecologic symptoms, endometriosis is associated with various systemic effects, including inflammation, altered body weight, and behavioral changes. Previous murine studies demonstrate that endometriosis is causally inked to increased pain sensitization, behavioral changes, and low body mass index (BMI). One possible cellular target that may mediate some of these findings is the hypocretin/orexin neurons. This neuronal system plays a role in regulating wakefulness/sleep cycles, pain perception, and appetite. We hypothesize that endometriosis alters activity level of the hypocretin/orexin (Hcrt) neuronal system. Mice underwent endometriosis induction surgeries (endo) or sham surgeries (sham) for the development of the experimental model. Immunocytochemistry was performed on harvested samples from the lateral hypothalamus, and activation levels of Hcrt cells were examined by quantifying the expression of phosphorylation of cAMP-responsive element binding protein (CREB) in these cells after an acute stress in sham and endo mice. Mice with endometriosis had greater Hcrt neurons activation than sham mice. Mice with endometriosis fed with high fat diet showed a lower fat/body weight and fat/lean tissue ratio compared to mice without endometriosis. There was no significant difference in food intake between sham and endometriosis mice. These results demonstrate that endometriosis is associated with low body mass and increased hypocretin/orexin activity, which could be implicated in the behavioral changes and to differences in body composition.

Familial risk for endometriosis and its interaction with smoking, age at menarche and body mass index: a population-based cohort study among siblings

OBJECTIVE

To quantify familial risk of endometriosis among full siblings and examine interactions between family history and smoking, age at menarche or body mass index (BMI).

DESIGN, SETTING AND POPULATION

Population-based nationwide cohort study.

METHODS

Using data from the Korean National Health Insurance and Screening Programme databases on kinship, healthcare utilisation, lifestyle and anthropometrics, we identified 2 109 288 women with full siblings and their environmental risk factors from 2002 to 2018. Familial risks were estimated using Cox proportional-hazards models, represented as incidence risk ratios (IRR) with 95% CI. Interaction between family history and smoking, age at menarche or BMI were assessed on an additive scale.

MAIN OUTCOME MEASURES

IRR of endometriosis among women with and without affected siblings.

RESULTS

From 19 195 women with affected siblings, 1126 developed endometriosis with an incidence of 35.45/10 000 person-years. Familial risk of endometriosis with versus without affected siblings was increased to IRR 2.75 (95% CI 2.25-3.36), and the highest risk was with affected twins (IRR 6.98; 95% CI 4.19-11.62). Women with both a family history and either smoking, early menarche or low BMI had a significantly higher risk of endometriosis compared with the general population and can be regarded as a high-risk group, the IRRs were 4.28 (95% CI 2.43-7.55), 3.47 (95% CI 2.82-4.26) and 3.09 (95% CI 2.68-3.56), respectively. Substantial effect modification of the associations was noted by smoking and early menarche, as their combined risk with family history exceeded the sum of their individual risks, which was also statistically significant.

CONCLUSION

Genetic factors are the primary contributor to the familial aggregation of endometriosis. Significant gene-environment interaction exists between family history and smoking or early menarche.

Clinical factors influencing the pregnancy outcome after laparoscopic treatment in endometriosis-associated infertility patients: a retrospective study

INTRODUCTION

Endometriosis is an illness caused by the presence of foci of endometrial implants outside the uterine cavity. Laparoscopy (minimally invasive surgical method) is considered as the definitive treatment for Endometriosis.

METHOD

Clinical data from January 2014 till December 2018, between the ages of 20 and 40 years were collected. A total of 175 women with pelvic Endometriosis complicated with infertility, underwent laparoscopy in our hospital, were followed up to assess fertility outcome. We analyzed using univariate logistic regression analysis as well as multivariate logistic analysis.

RESULTS

We analyzed the relationship between them by logistic regression analysis. Univariate logistic regression analysis indicated that the significant factors for influencing pregnancy were the following factors: age, infertility types: primary or secondary infertility, treatment with Gonadotrophin Releasing Hormone-agonist, r-AFS grade, operative method: excision or ablation. And multivariate logistic regression using all the factors also revealed that age, infertility types: primary or secondary, treatment with GnRH-a, revised- American Fertility Society grading and operative method: excision or ablation were positively correlated and were the significant factors to influence pregnancy outcome. While the other factors such as Body Mass Index, and endometriosis along with other gynecological pathology were not statistically significant.

CONCLUSIONS

In this study, we found out that age, infertility type, treatment with Laparoscopy surgery, use of GnRH-a after the operation, grading of the disease, and different types of operative methods were found to be significant and were found to be the factors which influenced the pregnancy outcome.

Introduction of Female Reproductive Processes and Reproductive Diseases

The female reproductive process is very complicated, including multiple processes. Each process is different and plays a vital role in reproduction. If some reproductive diseases occur, these processes will be abnormal, causing infertility problem. In this Chapter, we will describe the female reproductive process and their corresponding reproductive diseases.

Hypothetical roadmap towards endometriosis: prenatal endocrine-disrupting chemical pollutant exposure, anogenital distance, gut-genital microbiota and subclinical infections

BACKGROUND

Endometriosis is a gynaecological hormone-dependent disorder that is defined by histological lesions generated by the growth of endometrial-like tissue out of the uterus cavity, most commonly engrafted within the peritoneal cavity, although these lesions can also be located in distant organs. Endometriosis affects ~10% of women of reproductive age, frequently producing severe and, sometimes, incapacitating symptoms, including chronic pelvic pain, dysmenorrhea and dyspareunia, among others. Furthermore, endometriosis causes infertility in ~30% of affected women. Despite intense research on the mechanisms involved in the initial development and later progression of endometriosis, many questions remain unanswered and its aetiology remains unknown. Recent studies have demonstrated the critical role played by the relationship between the microbiome and mucosal immunology in preventing sexually transmitted diseases (HIV), infertility and several gynaecologic diseases.

OBJECTIVE AND RATIONALE

In this review, we sought to respond to the main research question related to the aetiology of endometriosis. We provide a model pointing out several risk factors that could explain the development of endometriosis. The hypothesis arises from bringing together current findings from large distinct areas, linking high prenatal exposure to environmental endocrine-disrupting chemicals with a short anogenital distance, female genital tract contamination with the faecal microbiota and the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis.

SEARCH METHODS

We performed a search of the scientific literature published until 2019 in the PubMed database. The search strategy included the following keywords in various combinations: endometriosis, anogenital distance, chemical pollutants, endocrine-disrupting chemicals, prenatal exposure to endocrine-disrupting chemicals, the microbiome of the female reproductive tract, microbiota and genital tract, bacterial vaginosis, endometritis, oestrogens and microbiota and microbiota-immune system interactions.

OUTCOMES

On searching the corresponding bibliography, we found frequent associations between environmental endocrine-disrupting chemicals and endometriosis risk. Likewise, recent evidence and hypotheses have suggested the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis. Hence, we can envisage a direct relationship between higher prenatal exposure to oestrogens or estrogenic endocrine-disrupting compounds (phthalates, bisphenols, organochlorine pesticides and others) and a shorter anogenital distance, which could favour frequent postnatal episodes of faecal microbiota contamination of the vulva and vagina, producing cervicovaginal microbiota dysbiosis. This relationship would disrupt local antimicrobial defences, subverting the homeostasis state and inducing a subclinical inflammatory response that could evolve into a sustained immune dysregulation, closing the vicious cycle responsible for the development of endometriosis.

WIDER IMPLICATIONS

Determining the aetiology of endometriosis is a challenging issue. Posing a new hypothesis on this subject provides the initial tool necessary to design future experimental, clinical and epidemiological research that could allow for a better understanding of the origin of this disease. Furthermore, advances in the understanding of its aetiology would allow the identification of new therapeutics and preventive actions.

Epidemiological profile of women with endometriosis: a retrospective descriptive study

Abstract Objectives: to describe the epidemiological and clinical profile of women with endometriosis and to determine the association with the prognostic characteristics of the disease. Methods: retrospective descriptive study involving 237 women attended at two referral hospitals for endometriosis, between 2011 and 2017. Associations between groups were estimated using logistic regression models. Results: most women (65.4%) were of reproductive age (29-39 years), with a body mass index in the range of 18.5-24.9 kg/m2 and a high prevalence (23-81%) of symptoms of the disease, with 49.5% being infertile. The average time of diagnosis was 5 years. Ovarian endometrioma and/or deep infiltrative endometriosis (DIE) were the most frequent type of endometriosis (87%), and 59% of patients were in the III/IV stage of the disease. Approximately 87% of women with surgical diagnosis were aged over 30, married (70%) and had lower parity. Dyspareunia was negatively associated with superficial endometriosis. Infertility was positively associated with age (30-39 years) and DIE in the uterine tubes; dysmenorrhea with DIE in the uterosacral ligament; cyclic intestinal complaints with DIE in the rectosigmoid and intestine, and with DIE classification and III/IVstage. Conclusions: knowing the epidemiological and clinical profile of Brazilian women with endometriosis can help in diagnosis and treatment planning.

Developing Preoperative Nomograms to Predict Any-Stage and Stage III-IV Endometriosis in Infertile Women

Study objective: To generate and validate nomograms to predict any-stage and stage III-IV endometriosis before surgery in infertile women.

Design: A single center retrospective cohort study.

Setting: University affiliated hospital.

Patients: Infertile patients (n = 1,016) who underwent reproductive surgery between July 1, 2016 and June 30, 2019.

Interventions: None.

Main outcome measurements: We randomly selected 2/3 of the included patients (667 patients, training sample) to analyze and generate predictive models and validated the models on the remaining patients (339 patients, validation sample). A multivariate logistic regression model was used with the training sample to select variables using a back stepwise procedure. Nomograms to predict any-stage and stage III–IV endometriosis were constructed separately. The discriminations and calibrations of both nomograms were tested on the overall population and a subgroup without endometrioma diagnosed on transvaginal sonography (TVS) of training and validation samples. The impact of different variables in these models was evaluated.

Results: There were 377 (55.7%) women in the training sample and 196 (57.8%) in the validation sample who were diagnosed with endometriosis. The nomogram predicting any-stage endometriosis had an area under the curve (AUC) of 0.760 for the training sample and 0.744 for the validation sample, with favorable calibrations in the overall population. However, the performance was significantly decreased in patients without endometrioma on TVS, with an AUC of 0.726 in the training sample and 0.694 in the validation sample. Similarly, the nomogram predicting stage III–IV endometriosis had an AUC of 0.833 and 0.793 for the training and validation samples, respectively, as well as a favorable calibration. However, the performance of the nomogram on patients without endometrioma on TVS was poor. Endometrioma on TVS strongly predicted both any stage and stage III–IV endometriosis on both samples.

Conclusion: We developed nomograms to predict any-stage and stage III–IV endometriosis but their performance were significantly decreased in patients without endometrioma on TVS. Endometrioma on TVS strongly predicted any and III–IV stage endometriosis in both sample groups. Therefore, we recommend that this study be used as encouragement to advance the utilization of advanced imaging for endometriosis for better clinical prognosis.

Endometriosis Associated Infertility: A Critical Review and Analysis on Etiopathogenesis and Therapeutic Approaches

Endometriosis represents a frequently diagnosed gynecological affliction in the reproductive timespan of women, defined by symptoms ranging from pelvic pain to infertility. A complex interplay between the genetic profile, hormonal activity, menstrual cyclicity, inflammation status, and immunological factors define the phenotypic presentation of endometriosis. To date, imaging techniques represent the gold standard in diagnosing endometriosis, of which transvaginal ultrasonography and magnetic resonance imaging bring the most value to the diagnostic step. Current medical treatment options for endometriosis-associated infertility focus on either stimulating the follicular development and ovulation or on inhibiting the growth and development of endometriotic lesions. Techniques of assisted reproduction consisting of superovulation with in vitro fertilization or intrauterine insemination represent effective treatment alternatives that improve fertility in patients suffering from endometriosis. Emerging therapies such as the usage of antioxidant molecules and stem cells still need future research to prove the therapeutic efficacy in this pathology.

Is body mass index associated with the incidence of endometriosis and the severity of dysmenorrhoea: a case-control study in China?

OBJECTIVE

Endometriosis is considered as a serious gynaecological disease in women at a reproductive age. Lower body mass index (BMI) is thought to be a risk factor. However, recent studies indicated that women with normal BMI were also more likely to develop endometriosis, suggesting the association with BMI is controversial. We therefore investigated the association of BMI and surgically diagnosed endometriosis in a cohort of Chinese women.

DESIGN

Retrospective case-control study.

SETTING

Tertiary hospital.

PATIENTS

709 women with endometriosis and 807 age matched controls between January 2018 and August 2019.

INTERVENTION

Age at diagnosis, parity, gravida, BMI and self-reported dysmenorrhoea status were collected and the association of BMI and endometriosis was analysed.

MEASUREMENT AND MAIN RESULTS

Overall, the median BMI was not different between patients and controls (21.1 kg/m² vs 20.9 kg/m², p=0.223). According to the BMI categories for Asians/Chinese by WHO (underweight: <18.5 kg/m², normal weight: 18.5-22.99 kg/m², overweight: 23-27.49 kg/m², obese: ≥27.50 kg/m²), overall, there was no difference in the association of BMI and endometriosis (p=0.112). 60% of patients were of normal weight. However, the OR of obese patients (BMI over 27.50 kg/m²) having endometriosis was1.979 (95% CI 1.15 to 3.52, p=0.0185), compared with women with normal weight. 50.3% patients reported dysmenorrhoea, and the OR of developing severe dysmenorrhoea in obese patients (BMI over 27.50 kg/m²) was 3.64 (95% CI 1.195 to 10.15, p=0.025), compared with patients with normal weight.

CONCLUSION

Our data demonstrate that overall there was no association between BMI and the incidence of endometriosis, but there was a significant increase in the incidence of endometriosis in obese women, compared with women with normal weight. Obesity was also a risk factor for severe dysmenorrhoea.

The estimated prevalence and incidence of endometriosis with the Korean National Health Insurance Service-National Sample Cohort (NHIS-NCS): A National Population-based Study

Background

The incidence and prevalence of endometriosis remain unclear due to diagnostic difficulties. Especially, there has been little information regarding the population-based epidemiology of endometriosis. The purpose of this study is to estimate the prevalence and incidence of endometriosis in Korea based on the health insurance claims data.

Methods

This study is a retrospective cohort study using the Korean National Health Insurance Service-National Sample Cohort, which correspond to approximately 1 million Korean populations from 2002 to 2013. Patients aged 15–54 years were selected, and the prevalence and incidence of endometriosis were estimated by time and age groups.

Results

The age-adjusted prevalence rate of endometriosis also increased from 2.12 per 1,000 persons (95% confidence interval [CI], 2.01–2.24) in 2002 to 3.56 per 1,000 persons (95% CI, 3.40–3.71) in 2013. The average adjusted incidence showed no statistically significant increase. However, the age-specific incidence of the 15–19 and 20–24 years age groups increased significantly from 0.24 and 1.29 per 1,000 persons in 2003 to 2.73 and 2.71 per 1,000 persons in 2013 (R² = 0.93 and 0.77, P < 0.001), while the incidence rate of the age group 40–44 and 45–49 years decreased from 2.36 and 1.72 per 1,000 persons in 2003 to 0.81 and 0.27 per 1,000 persons in 2013 (R² = 0.83 and 0.89, P < 0.001).

Conclusion

The prevalence and incidence of endometriosis in Korean women were lower than that of previous reports in high-risk population studies. Furthermore, we found a significant increase in the diagnosis of endometriosis in younger age groups.

Associations of perinatal characteristics with endometriosis: a nationwide birth cohort study

BACKGROUND

Perinatal characteristics are associated with subsequent risk of several chronic diseases. Previous studies regarding endometriosis were based on small samples and retrospective data and were limited by unmeasured confounding bias, leading to conflicting and inconclusive findings. We investigated the associations of maternal and birth characteristics with risk of endometriosis among Swedish women of reproductive age.

METHODS

This total-population register-based cohort study consisted of 628 312 singleton women born in Sweden between 1973 and 1987, who were followed for diagnosed endometriosis from age 15 years until the end of 2012. Multivariable Cox regression was applied to examine associations with perinatal characteristics. Residual unmeasured confounding was assessed through within-family and E-value analyses.

RESULTS

During follow-up, 8262 women received an endometriosis diagnosis. There were clear dose-response/linear associations of endometriosis with lower maternal education, endometriosis in the mother [adjusted hazard ratio (aHR): 2.24, 95% confidence interval (CI): 2.04-2.46], maternal smoking during pregnancy (aHR: 1.18, 95% CI: 1.04-1.33 for moderate smoker and aHR: 1.36, 95% CI: 1.18-1.57 for heavy smoker vs non-smoker), lower birthweight, and lower birthweight-for-gestational age (aHR: 0.93 per standard deviation increase, 95% CI: 0.91-0.95). Within-family and E-value analyses suggested that these perinatal characteristics are robust predictors of the incidence of endometriosis. We also found that an estimated 26% of the association between maternal smoking and early-onset endometriosis could be explained by birthweight-for-gestational age.

CONCLUSION

This study finds support for fetal origins of endometriosis, in that exposure to adverse environment or restricted development during the perinatal period may increase the risk. Further research is needed to provide an understanding of the underlying mechanisms.

A diagnosis of rheumatoid arthritis, endometriosis or IBD is associated with later onset of fibromyalgia and chronic widespread pain

BACKGROUND

Widespread pain is a common comorbidity in several chronic diseases and is suspected to be caused by pain resulting from the underlying disease that has provoked a state of central sensitization. However, this argument is currently limited by evidence that has insufficiently captured the temporal nature of the relationship between diagnosis of the underlying disease and onset of widespread pain. The aim of this study was to investigate if patients with rheumatoid arthritis (RA), endometriosis or inflammatory bowel disease (IBD), have a higher risk of developing widespread pain (fibromyalgia or chronic widespread pain [CWP]).

METHODS

Using the Swedish Skåne Healthcare register on health care consultation, a cohort of 889,938 adult patients were followed from 2007 to 2016 and incident cases of RA, endometriosis or IBD and of fibromyalgia and CWP were identified by registered diagnoses. Using Poisson regression, we calculated incidence rate ratios (IRR) adjusted for sex, age, education and propensity to seek health care.

RESULTS

For patients with RA the IRR for later fibromyalgia was 3.64 (95% CI: 2.75-4.81) compared to patients without RA, for CWP it was 2.96 (95% CI: 1.81-4.86). For endometriosis patients the IRR for fibromyalgia was 2.83 (95% CI: 1.96-4.08) and for CWP 5.02 (95% CI: 3.10-8.13). IBD patients had an IRR = 2.32 (95% CI: 1.58-3.42) for fibromyalgia and 1.42 (95% CI: 0.93-2.17) for CWP.

CONCLUSIONS

This study shows that RA, endometriosis and IBD are all risk factors for later fibromyalgia and CWP, consistent with a hypothesis of central sensitization as an effect of a painful underlying condition.

SIGNIFICANCE

We show that RA, endometriosis and IBD predisposes for later fibromyalgia and CWP, a common hypothesis previously difficult to verify due to lack of longitudinal data. The results inform further research regarding the aetiology of fibromyalgia and CWP and stress the need of clinical focus on the pain itself in chronic diseases with pain as a symptom.

A cohort study of 49 933 women with surgically verified endometriosis: Increased incidence of breast cancer below the age of 40

INTRODUCTION

The association between endometriosis and breast cancer is unclear. We assessed the risk of breast cancer in women with surgically verified endometriosis, with special focus on the age at cancer diagnosis, time from endometriosis diagnosis and breast cancer histology.

MATERIAL AND METHODS

All women with first endometriosis-associated diagnoses occurring concomitantly with relevant surgical codes during 1987-2012 were retrieved from the Finnish Hospital Discharge Register in Finland. Breast cancers diagnosed after the endometriosis diagnosis were identified from the Finnish Cancer Registry. The Finnish female population served as the reference. The endometriosis cohort consisted of 49 933 women (23 210 cases of ovarian, 20 187 peritoneal and 2372 deep infiltrating endometriosis). The outcome measure was the standardized incidence ratio (SIR) with 95% confidence interval (95% CI) of breast cancer calculated for the whole cohort and for the subtypes of endometriosis, stratified by the age at breast cancer diagnosis, histology and time from endometriosis diagnosis.

RESULTS

The overall risk of breast cancer (1555 cases) was similar to the reference population (SIR 0.99; 95% CI 0.94-1.03), did not differ in types of endometriosis, and was similar for ductal and lobular breast cancer. However, the SIR of breast cancer was increased in the age group of 20-29 years (SIR 4.44; 95% CI 2.22-7.94) and in the age group of 30-39 years (SIR 1.28; 95% CI 1.03-1.57). The risk of in situ breast cancer (170 cases) was increased in the entire endometriosis cohort (SIR 1.25; 95% CI 1.07-1.44).

CONCLUSIONS

The overall risk of breast cancer in women with surgically verified endometriosis was similar to that of general population. However, the risk of breast cancer at young age was increased. Young women with surgically verified endometriosis represent highly symptomatic patients with more frequent surgeries and additional therapies that might also contribute to the risk of breast cancer.

Developmental origins of endometriosis: a Swedish cohort study

BACKGROUND

Endometriosis is a chronic condition affecting women of reproductive age and is associated with multiple health burdens. Yet, findings regarding its 'developmental origins' are inconsistent. We aimed to investigate the associations of birth characteristics with endometriosis. We also explored potential mediation by adult social and reproductive factors.

METHODS

This cohort study consisted of 3406 women born in Uppsala, Sweden, between 1933 and 1972. We used data from archived birth records and endometriosis diagnoses at ages 15-50 recorded in the national patient registers. Socioeconomic and reproductive characteristics were obtained from routine registers. HRs were estimated from Cox regression.

RESULTS

During the follow-up, 111 women have been diagnosed with endometriosis, and most cases are external endometriosis (ie, outside the uterus, n=91). Lower standardised birth weight for gestational age was associated with increased rate of endometriosis (HR 1.35 per standard deviation decrease; 95% CI 1.08 to 1.67). This increased rate was also detected among women with fewer number of live births (HR 2.38; 95% CI 1.40 to 4.07 for one child vs ≥2 children; HR 6.09; 95% CI 3.88 to 9.57 for no child vs ≥2 children) and diagnosed infertility problem (HR 2.00; 95% CI 1.10 to 3.61) prior to endometriosis diagnosis. All the observed associations were stronger for external endometriosis. However, no evidence was found that number of births was the mediator of the inverse association between standardised birth weight and endometriosis.

CONCLUSION

This study supports the developmental origins theory and suggests that exposure to growth restriction during the fetal period is associated with increased risk of endometriosis during reproductive years.

Impact of Endometriosis-Related Adhesions on Quality of Life among Infertile Women

BACKGROUND

Endometriosis is considered the most common cause of pelvic adhesions in women. Endometriosisassociated adhesions could result in the formation of fibrous bands, which contain endometriotic glands, stroma and scarring. The aim of this study was to identify the impact of endometriosis-related adhesions on quality of life among infertile women.

MATERIALS AND METHODS

This descriptive study was conducted at Endoscopic Unit, in Zagazig University Hospitals, Egypt. Oral consent for participation in this study was taken from 109 women who were candidates for laparoscopy as infertile cases and were diagnosed with endometriosis. They were classified into two groups namely, group I (n=41) who had endometriosis with adhesions and group II (n=68) who had endometriosis without adhesions. A structured interviewing form, adhesion scoring method of the American Fertility Society, and Global Quality of Life Scale were used to collect required information.

RESULTS

The prevalence of adhesions resulted from endometriosis was 37.6%. Demographic characteristics of the women with endometriosis-related adhesions were not significantly different from those of women without endometriosis- related adhesions. The most common location for endometriotic adhesions was adnexal adhesion (51.2%) followed by adhesion of anterior abdominal wall (24.4%). Quality of life was significantly impacted by endometriosisrelated adhesions (P=0.002).

CONCLUSION

A high percentage of studied patients had a moderate degree of adhesions. Adhesions caused by endometriosis had an impact on quality of life of the studied women.

Clinical diagnosis of endometriosis: a call to action

Endometriosis can have a profound impact on women's lives, including associated pain, infertility, decreased quality of life, and interference with daily life, relationships, and livelihood. The first step in alleviating these adverse sequelae is to diagnose the underlying condition. For many women, the journey to endometriosis diagnosis is long and fraught with barriers and misdiagnoses. Inherent challenges include a gold standard based on an invasive surgical procedure (laparoscopy) and diverse symptomatology, contributing to the well-established delay of 4-11 years from first symptom onset to surgical diagnosis. We believe that remedying the diagnostic delay requires increased patient education and timely referral to a women's healthcare provider and a shift in physician approach to the disorder. Endometriosis should be approached as a chronic, systemic, inflammatory, and heterogeneous disease that presents with symptoms of pelvic pain and/or infertility, rather than focusing primarily on surgical findings and pelvic lesions. Using this approach, symptoms, signs, and clinical findings of endometriosis are anticipated to become the main drivers of clinical diagnosis and earlier intervention. Combining these factors into a practical algorithm is expected to simplify endometriosis diagnosis and make the process accessible to more clinicians and patients, culminating in earlier effective management. The time has come to bridge disparities and to minimize delays in endometriosis diagnosis and treatment for the benefit of women worldwide.

Intestinal endometriosis: Diagnostic ambiguities and surgical outcomes

BACKGROUND

Endometriosis is a common disease for women of reproductive age. However, when it involves intestines, it is difficult to diagnose preoperatively because its symptoms overlap with other diseases and the results of evaluations can be unspecific. Thus it is important to know the clinical characteristics of intestinal endometriosis and how to exactly diagnose.

AIM

To analyze patients in whom intestinal endometriosis was diagnosed after surgical treatments, and to evaluate the clinical characteristics of preoperatively misdiagnosed cases.

METHODS

We retrospectively reviewed the pathologic reports of 30 patients diagnosed as having intestinal endometriosis based on surgical specimens between January 2000 and December 2017. We reviewed their clinical characteristics and surgical outcomes.

RESULTS

Twenty-three (76.6%) patients showed symptoms associated with endometriosis, with dysmenorrhea being the most common (n = 9, 30.0%). Thirteen patients (43.3%) had a history of pelvic surgeries. Ten patients (33.3%) had a history of treatment for endometriosis. Only 4 patients (13.3%) had a diagnosis of endometriosis based on endoscopic biopsy findings. According to preoperative evaluations, 13 patients (43.3%) had an initial diagnosis of pelvic endometriosis and 17 patients (56.6%) were misdiagnosed as having other diseases. The most common misdiagnosis was submucosal tumor in the large intestine (n = 8, 26.7%), followed by malignancies of the colon/rectum (n = 3, 10.0%) and ovary (n = 3, 10.0%). According to the Clavien-Dindo classification, 5 complications were grade I or II and 2 complications were grade IIIa. The median follow-up period was 26.9 (0.6-132.1) mo, and only 1 patient had a recurrence of endometriosis.

CONCLUSION

Intestinal endometriosis is difficult to diagnose preoperatively because it mimics various intestinal diseases. Thus, if women of reproductive age have ambiguous symptoms and signs with nonspecific radiologic and/or endoscopic findings, intestinal endometriosis should be included in the differential diagnosis.

Endometriosis

Endometriosis is a common inflammatory disease characterized by the presence of tissue outside the uterus that resembles endometrium, mainly on pelvic organs and tissues. It affects ~5-10% of women in their reproductive years - translating to 176 million women worldwide - and is associated with pelvic pain and infertility. Diagnosis is reliably established only through surgical visualization with histological verification, although ovarian endometrioma and deep nodular forms of disease can be detected through ultrasonography and MRI. Retrograde menstruation is regarded as an important origin of the endometrial deposits, but other factors are involved, including a favourable endocrine and metabolic environment, epithelial-mesenchymal transition and altered immunity and inflammatory responses in genetically susceptible women. Current treatments are dictated by the primary indication (infertility or pelvic pain) and are limited to surgery and hormonal treatments and analgesics with many adverse effects that rarely provide long-term relief. Endometriosis substantially affects the quality of life of women and their families and imposes costs on society similar to those of other chronic conditions such as type 2 diabetes mellitus, Crohn's disease and rheumatoid arthritis. Future research must focus on understanding the pathogenesis, identifying disease subtypes, developing non-invasive diagnostic methods and targeting non-hormonal treatments that are acceptable to women who wish to conceive.

Risk for and consequences of endometriosis: A critical epidemiologic review

Endometriosis affects approximately 10% of women of reproductive age. Characteristics robustly associated with a greater risk for endometriosis include early age at menarche, short menstrual cycle length, and lean body size, whereas greater parity has been associated with a lower risk. Relationships with other potential characteristics including physical activity, dietary factors, and lactation have been less consistent, partially because of the need for rigorous data collection and a longitudinal study design. Critical methodologic complexities include the need for a clear case definition; valid selection of comparison/control groups; and consideration of diagnostic bias and reverse causation when exploring demographic characteristics, medical history, and lifestyle factors. Reviewers and editors must demand a detailed description of rigorous methods to facilitate comparison and replication to advance our understanding of endometriosis.