Endometriosis, dysmenorrhoea and diet

[The importance of nutrition in the prevention of endometriosis - Systematic review]

Introduction

Background and objective: endometriosis is a hormone-dependent disorder characterized by the presence of endometrial-like tissue in extrauterine sites, which can trigger a chronic inflammatory reaction. This disease mainly affects women of childbearing age and can have a negative impact on their physical, mental and social well-being. There are eating patterns considered as anti-inflammatory, such as the Mediterranean diet, which could help in the prevention and treatment of endometriosis. The objective of this review was to know the relationship between the consumption of different food groups and the prevention of endometriosis. Materials and methods: a systematic review was carried out following the PRISMA methodology. PubMed, Scopus, Cochrane Library and Web of Science databases were consulted. Studies published between 2013 and 2023 were selected, accessible in full text, written in English and Spanish and including a sample of women with endometriosis and/or healthy women, in addition to evaluating the relationship between diet and endometriosis. Unrelated articles, systematic reviews or meta-analyses, pilot studies and studies conducted in animals were excluded. Results: a total of ten studies were included. The consumption of fruits, vegetables (not cruciferous), dairy products, fish, potatoes, legumes, vitamins (A, C, D and B12), monounsaturated and polyunsaturated fatty acids and minerals (calcium, potassium and magnesium) seems to reduce the risk of endometriosis. Conclusions: further studies investigating the relationship between consumption of different food groups and risk of endometriosis are needed.

High-fat diet-negative impact on female fertility: from mechanisms to protective actions of antioxidant matrices

Introduction

Excessive calorie intake poses a significant threat to female fertility, leading to hormonal imbalances and reproductive challenges. Overconsumption of unhealthy fats exacerbates ovarian dysfunction, with an overproduction of reactive oxygen species causing oxidative stress, impairing ovarian follicle development and leading to irregular ovulation and premature ovarian failure. Interest in biological matrices with high antioxidant properties to combat diet-related oxidative stress has grown, as they contain various bioactive factors crucial for neutralizing free radicals potentially preventing female reproductive health. This systematic review evaluates the female reproductive impact of biological matrices in mitigating oxidative damages induced by over calory habits and, in particular, high fat diets.

Methods

A comparative approach among mammalian models was utilized to interpret literature available data. This approach specifically investigates the antioxidant mechanisms of biological matrices on early and late ovarian folliculogenesis, under physiological and hormone-induced female reproductive cycle. Adhering to the PRISMA 2020 guidelines, only English-language publications from peer-reviewed international indexes were considered.

Results

The analysis of 121 publications meeting the inclusion criteria facilitated the identification of crucial components of biological matrices. These components, including carbocyclic sugars, phytonutrients, organosulfur compounds, and vitamins, were evaluated for their impact on ovarian follicle resilience, oocyte quality, and reproductive lifespan. The detrimental effects of oxidative stress on female fertility, particularly exacerbated by high saturated fat diets, are well-documented. In vivo studies across mammalian preclinical models have underscored the potential of antioxidants derived from biological matrices to mitigate diet-induced conditions. These antioxidants enhance steroidogenesis and ovarian follicle development, thereby improving oocyte quality. Additionally, discussions within these publications emphasized the clinical significance of these biological matrices, translating research findings into practical applications for female health.

Conclusion

Further research is essential to fully exploit the potential of these matrices in enhancing female reproduction and mitigating the effects of diets rich in fatty acids. This requires intensified in vitro studies and comprehensive collection of in vivo data before clinical trials. The promotion of ovarian resilience offers promising avenues for enhancing understanding and advancing female reproductive health world-wide.

An Assessment of Women's Knowledge of the Menstrual Cycle and the Influence of Diet and Adherence to Dietary Patterns on the Alleviation or Exacerbation of Menstrual Distress

A growing number of women of reproductive age experience menstrual disorders. The menstrual cycle is considerably influenced by dietary habits, physical activity, and the use of stimulants. The main aim of this study was to assess women's knowledge about the menstrual cycle and the influence of diet and lifestyle factors on menstrual symptoms, and to identify dietary models that may alleviate or exacerbate menstrual distress. A total of 505 young women participated in the study. Nearly 90% of the respondents reported at least one menstrual disorder, mostly dysmenorrhea (70.7%), whereas secondary amenorrhea was least frequently reported (13.8%) (p = 0.002). In the study population, dysmenorrhea/menstrual distress was linked with higher consumption frequency of certain food groups. Women with severe dysmenorrhea consumed refined cereal products, processed meat, sugar, and water significantly more frequently than women with moderate menstrual pain. In turn, sweetened dairy products, animal fats, and fruit were consumed more frequently by women with low intensity of menstrual pain (mild pain). Significant differences in knowledge about the menstrual cycle and physiological changes in the body were observed between the compared dietary models.

The relationship between endometriosis and diet

Endometriosis is an oestrogen dependent, benign, chronic inflammatory disease characterised by ectopic endometrial implants. Current medical practices for the treatment of the disease are associated with several side effects over long periods, making the effect of diet on endometriosis an important aspect. To alleviate this need, we review related literature to identify the association between nutrients and endometriosis and to find the probable therapeutic effects of the nutrients and foods on endometriosis. Despite variations among the findings, several of the prior studies point to an inverse relationship between endometriosis and the consumption of fruits, vegetables, dairy products, and omega-3 fatty acids. Another common finding among the studies is the increased risk of endometriosis with higher consumption of trans-unsaturated fatty acids and red meat. Due to the limited size of the samples in existing literature, however, significance of the association between diet and endometriosis is not conclusive. Further research is needed to better identify the role of diet on endometriosis.

Complementary therapy for endometriosis related pelvic pain

In the setting of a global pandemic, it is vastly important now more than ever that patients have agency and control over pain management when living with a debilitating chronic pain disease such as endometriosis. We present a review of the available literature on the most popular and easily accessible complementary pain management therapies for endometriosis including Transcutaneous Electrical Nerve stimulator (TENS) units, diets, Cannabidiol (CBD), turmeric, meditation, yoga, and acupuncture. These are worthwhile recommendations; however, the data for each is limited and more research is needed to further support each of its use.

The Role of Dietary Fats in the Development and Treatment of Endometriosis

Endometriosis is an estrogen-dependent disease in women of childbearing age that affects approximately 5–15% of the female population. The etiology of endometriosis is complex, multifaceted, and not fully understood. In endometriosis, which is an estrogen-related chronic inflammatory condition, estrogen plays a major role in endometrial cellular growth. High estrogen levels could be another risk factor for developing endometriosis. The aim of this review is to update knowledge on the impact of dietary fats on the development of endometriosis and chronic inflammation in women with endometriosis and diet therapy. Dietary fat may be linked with the progression and development of endometriosis, but studies have been contradictory due to various issues including sample size, different study designs, and different methodological aspects. Results have shown that the risk of endometriosis may increase with a higher consumption of products rich in saturated fats, especially palmitic acid and trans-unsaturated fatty acids. Monounsaturated fats and omega-3 polyunsaturated fatty acids may likely be connected with a lower risk of developing endometriosis and with reductions in the severity of disease. Monounsaturated fats, omega-3 polyunsaturated fatty acids, and a suitable eicosapentaenoic acid to arachidonic acid ratio can be used in diet therapy to improve quality of life by reducing pain and inflammation. Further research is needed in order to fully understand the influence of dietary fats on the risk of development of this disease.

ESHRE guideline: endometriosis

STUDY QUESTION

How should endometriosis be diagnosed and managed based on the best available evidence from published literature?

SUMMARY ANSWER

The current guideline provides 109 recommendations on diagnosis, treatments for pain and infertility, management of disease recurrence, asymptomatic or extrapelvic disease, endometriosis in adolescents and postmenopausal women, prevention and the association with cancer.

WHAT IS KNOWN ALREADY

Endometriosis is a chronic condition with a plethora of presentations in terms of not only the occurrence of lesions, but also the presence of signs and symptoms. The most important symptoms include pain and infertility.

STUDY DESIGN SIZE DURATION

The guideline was developed according to the structured methodology for development of ESHRE guidelines. After formulation of key questions by a group of experts, literature searches and assessments were performed. Papers published up to 1 December 2020 and written in English were included in the literature review.

PARTICIPANTS/MATERIALS SETTING METHODS

Based on the collected evidence, recommendations were formulated and discussed within specialist subgroups and then presented to the core guideline development group (GDG) until consensus was reached. A stakeholder review was organized after finalization of the draft. The final version was approved by the GDG and the ESHRE Executive Committee.

MAIN RESULTS AND THE ROLE OF CHANCE

This guideline aims to help clinicians to apply best care for women with endometriosis. Although studies mostly focus on women of reproductive age, the guideline also addresses endometriosis in adolescents and postmenopausal women. The guideline outlines the diagnostic process for endometriosis, which challenges laparoscopy and histology as gold standard diagnostic tests. The options for treatment of endometriosis-associated pain symptoms include analgesics, medical treatments and surgery. Non-pharmacological treatments are also discussed. For management of endometriosis-associated infertility, surgical treatment and/or medically assisted reproduction are feasible. While most of the more recent studies confirm previous ESHRE recommendations, there are five topics in which significant changes to recommendations were required and changes in clinical practice are to be expected.

LIMITATIONS REASONS FOR CAUTION

The guideline describes different management options but, based on existing evidence, no firm recommendations could be formulated on the most appropriate treatments. Also, for specific clinical issues, such as asymptomatic endometriosis or extrapelvic endometriosis, the evidence is too scarce to make evidence-based recommendations.

WIDER IMPLICATIONS OF THE FINDINGS

The guideline provides clinicians with clear advice on best practice in endometriosis care, based on the best evidence currently available. In addition, a list of research recommendations is provided to stimulate further studies in endometriosis.

STUDY FUNDING/COMPETING INTERESTS

The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings, with the literature searches and with the dissemination of the guideline. The guideline group members did not receive payments. C.M.B. reports grants from Bayer Healthcare and the European Commission; Participation on a Data Safety Monitoring Board or Advisory Board with ObsEva (Data Safety Monitoring Group) and Myovant (Scientific Advisory Group). A.B. reports grants from FEMaLE executive board member and European Commission Horizon 2020 grant; consulting fees from Ethicon Endo Surgery, Medtronic; honoraria for lectures from Ethicon; and support for meeting attendance from Gedeon Richter; A.H. reports grants from MRC, NIHR, CSO, Roche Diagnostics, Astra Zeneca, Ferring; Consulting fees from Roche Diagnostics, Nordic Pharma, Chugai and Benevolent Al Bio Limited all paid to the institution; a pending patent on Serum endometriosis biomarker; he is also Chair of TSC for STOP-OHSS and CERM trials. O.H. reports consulting fees and speaker's fees from Gedeon Richter and Bayer AG; support for attending meetings from Gedeon-Richter, and leadership roles at the Finnish Society for Obstetrics and Gynecology and the Nordic federation of the societies of obstetrics and gynecology. L.K. reports consulting fees from Gedeon Richter, AstraZeneca, Novartis, Dr KADE/Besins, Palleos Healthcare, Roche, Mithra; honoraria for lectures from Gedeon Richter, AstraZeneca, Novartis, Dr KADE/Besins, Palleos Healthcare, Roche, Mithra; support for attending meetings from Gedeon Richter, AstraZeneca, Novartis, Dr KADE/Besins, Palleos Healthcare, Roche, Mithra; he also has a leadership role in the German Society of Gynecological Endocrinology (DGGEF). M.K. reports grants from French Foundation for Medical Research (FRM), Australian Ministry of Health, Medical Research Future Fund and French National Cancer Institute; support for meeting attendance from European Society for Gynaecological Endoscopy (ESGE), European Congress on Endometriosis (EEC) and ESHRE; She is an advisory Board Member, FEMaLe Project (Finding Endometriosis Using Machine Learning), Scientific Committee Chair for the French Foundation for Research on Endometriosis and Scientific Committee Chair for the ComPaRe-Endometriosis cohort. A.N. reports grants from Merck SA and Ferring; speaker fees from Merck SA and Ferring; support for meeting attendance from Merck SA; Participation on a Data Safety Monitoring Board or Advisory Board with Nordic Pharma and Merck SA; she also is a board member of medical advisory board, Endometriosis Society, the Netherlands (patients advocacy group) and an executive board member of the World Endometriosis Society. E.S. reports grants from National Institute for Health Research UK, Rosetrees Trust, Barts and the London Charity; Royalties from De Gruyter (book editor); consulting fees from Hologic; speakers fees from Hologic, Johnson & Johnson, Medtronic, Intuitive, Olympus and Karl Storz; Participation in the Medicines for Women's Health Expert Advisory Group with Medicines and Healthcare Products Regulatory Agency (MHRA); he is also Ambassador for the World Endometriosis Society. C.T. reports grants from Merck SA; Consulting fees from Gedeon Richter, Nordic Pharma and Merck SA; speaker fees from Merck SA, all paid to the institution; and support for meeting attendance from Ferring, Gedeon Richter and Merck SA. The other authors have no conflicts of interest to declare.

DISCLAIMER

This guideline represents the views of ESHRE, which were achieved after careful consideration of the scientific evidence available at the time of preparation. In the absence of scientific evidence on certain aspects, a consensus between the relevant ESHRE stakeholders has been obtained. Adherence to these clinical practice guidelines does not guarantee a successful or specific outcome, nor does it establish a standard of care. Clinical practice guidelines do not replace the need for application of clinical judgement to each individual presentation, nor variations based on locality and facility type. ESHRE makes no warranty, express or implied, regarding the clinical practice guidelines and specifically excludes any warranties of merchantability and fitness for a particular use or purpose (Full disclaimer available at www.eshre.eu/guidelines.).

Does Nutrition Affect Endometriosis?

Endometriosis is a hormone-related, chronic inflammation in women of childbearing age. The aetiology and pathogenesis of endometriosis are not yet fully understood. For other illnesses classed as lifestyle diseases, the link between nutrition and pathogenesis has already been researched and proven. With regard to these findings, the question continues to arise as to whether and how a specific diet and lifestyle could also influence pathogenesis and the progression of endometriosis. The aim of this review is to examine the data and determine what influence nutrition has on the development of endometriosis or on existing disease. The study results currently available do not permit a clear, scientific recommendation or indicate a detailed diet. In summary, it can be said that fish oil capsules in combination with vitamin B ₁₂ have been associated with a positive effect on endometriosis symptoms (particularly of dysmenorrhoea). Alcohol and increased consumption of red meat and trans fats are associated with a negative effect. The results of the studies listed with regard to fruit and vegetables, dairy products, unsaturated fats, fibre, soy products and coffee are not clear. Therefore, the general recommendations for a balanced and varied diet in line with the guidelines of the Deutsche Gesellschaft für Ernährung e. V. [German Nutrition Society] apply, along with the recommendation to cut out alcohol. In order to be able to derive more concrete recommendations, we require further studies to investigate the influence of nutrition on endometriosis.

Relationship between Symptoms in Women with Endometriosis and Lifestyles: a Qualitative Interview Study

Endometriosis is a common condition that affects reproductive-aged women and is characterized by the presence of endo-metrial tissue outside the uterine cavity with nodules and lesions. The study aimed to analyze lifestyles of women affected by endometriosis in relation with their symptoms. In this observational study, 735 Italian women have been interviewed online through a questionnaire structured in two parts. The first part was mainly anamnestic, focused on gathering information about the age, the stage of disease, comorbidities, involved organs, symptomatology, chirurgical treatment, induced menopause. The second part focused on the individual characteristics and lifestyle of the patients such as the body mass index, physical activity, quality of sleep, and the diet. The results showed how a healthy diet and a regular physical activity reduce drastically the symptoms of the patients.

Menstrual Problems and Lifestyle among Spanish University Women

Menstrual problems affect many young women worldwide, conditioning both their academic performance and quality of life. This study sought to analyse the prevalence of menstrual problems and their possible relationship with lifestyle among Spanish university women, as part of a research project (UniHcos Project) involving a cohort of 11 Spanish universities with 7208 university students. A descriptive analysis was performed using the bivariate chi-square test and the Student’s t-test together with a binary logistic regression, in which the dependent variable was ‘suffering from menstrual problems’. Menstrual problems were identified in 23.8% of the students, representing women who paid more visits to the doctor and to emergency rooms, and who consumed more painkillers and contraceptives. In relation to dietary preferences, menstrual problems were 1.39 (CI 95% 1.22–1.61; p = 0.000) times more likely among women classified as high-risk alcohol users according to the AUDIT questionnaire, and 1.187 (CI 95% 1.029–1.370; p = 0.019) times greater among those who consumed sweets daily, 1.592 (CI 95% 1.113–2.276; p = 0.011) times more frequent among those who eat fish daily, and 1.199 (CI 95% 1.004–1.432; p = 0.045) times greater among those who were dieting. Menstrual problems affect many college students and potentially modifiable lifestyle variables exist which may influence their prevalence. It would be interesting to develop programmes to promote women’s health in the university context.

Experiences of health after dietary changes in endometriosis: a qualitative interview study

OBJECTIVES

Endometriosis is a chronic disease with no known cure. Persons affected by this disease often use complementary therapies such as dietary changes to reduce their symptoms, and so it is important to investigate whether and how these therapies affect endometriosis symptoms. The aim of this study was to explore how persons with endometriosis experienced their health after dietary changes.

DESIGN

Semi-structured qualitative interviews were conducted with 12 persons with endometriosis who had made individual dietary changes aimed at decreasing their endometriosis symptoms. The interviews were recorded and transcribed verbatim, and analysed using thematic analysis.

SETTING

Region Västra Götaland and the estern part of Central Sweden, Sweden.

PARTICIPANTS

Twelve persons with endometriosis aged 28 to 44 were recruited from two Swedish endometriosis support forums on the Internet.

RESULTS

Participants experienced an increase in well-being and a decrease in symptoms following their dietary and lifestyle changes. They also felt that the dietary changes led to increased energy levels and a deeper understanding of how they could affect their health by listening to their body's reactions. The participants understood that they could influence their symptoms through lifestyle changes. Support from family and friends was important in implementing and sustaining the dietary changes. However, the participants stressed the lack of support from healthcare professionals.

CONCLUSIONS

This study contributes to filling the knowledge gap about dietary strategies in endometriosis and lifestyle change as a method of alleviating suffering and increasing well-being. An important finding is that the participants experienced decreased symptoms and increased well-being after adopting an individually-adapted diet. Healthcare professionals should take their patients' knowledge and experience into consideration, and allow patients to participate in their own care. Further research is necessary to give evidenced-based dietary advices in endometriosis.

Factors associated with deep infiltrating endometriosis versus ovarian endometrioma in China: a subgroup analysis from the FEELING study

BACKGROUND

To compare potential factors associated with deep infiltrating endometriosis (DIE) versus ovarian endometrioma (OMA) among endometriosis patients in China.

METHODS

A subgroup analysis of factors associated with DIE versus OMA was performed in Chinese women from the FEELING study. This study included 156 OMA patients and 78 DIE patients. Retrospective information on symptoms and previous medical history was collected via face-to-face interviews; patients also completed a questionnaire to provide information on current habits. Univariate and multivariate logistic regression analyses were conducted to identify potential factors that are associated with DIE versus OMA.

RESULTS

From univariate analysis, women who were married, at older age, had any siblings, prior pregnancy, or longer time since age at menarche on the day of visit were more likely to be diagnosed with DIE (P < 0.05). Also, the incidence of previous uterine surgery, menstrual and ovulatory disorders, deep dyspareunia, and gastrointestinal symptoms during menstruation were major factors that were significantly associated with the diagnosis of DIE (P < 0.05). Multivariate analysis showed that women with any siblings, gastrointestinal symptoms during menstruation, or eating a greater number of fruit/vegetables per day were more likely to be diagnosed with DIE. Meanwhile, eating organic food and experiencing stress were major factors that are associated with the diagnosis of OMA.

CONCLUSIONS

The findings provide additional information on the potential risk factors that are associated with DIE, compared with OMA among Chinese endometriosis patients. The results may help to better understand DIE versus OMA, and aid in earlier risk stratification and diagnosis of the patients.

TRIAL REGISTRATION

NCT01351051 . Registered 10 May 2011.

Herbal fertility treatments used in North America from colonial times to 1900, and their potential for improving the success rate of assisted reproductive technology

This paper serves to fill a gap in the literature regarding evidence for the use of botanical remedies in the promotion of fertility. It examines the botanical remedies that were used in North America (1492-1900) for all stages of reproduction from preconception to birth, and discusses their potential for future use with present-day infertility treatments. Each medicinal plant discussed in this paper is assessed using an ethnomedicinal methodology that entails examining the published ethnobotanical, phytochemical and pharmacological data. A few clinical trials have shown that there is potential for medicinal plants to improve the success rate of assisted reproductive technology (ART) treatment if used in an integrated manner, similar to the integrated use of traditional Chinese medicine with ART treatment. For example, research has shown that older women who become pregnant have a high miscarriage rate, and this is one area that complementary and alternative medicines can address.

Urinary Phytoestrogen Concentrations Are Not Associated with Incident Endometriosis in Premenopausal Women

BACKGROUND

Phytoestrogens have been associated with subtle hormonal changes, but their effects on endometriosis are largely unknown.

OBJECTIVE

We assessed the association between urinary concentrations of phytoestrogens and incident endometriosis.

METHODS

We included an operative sample of 495 premenopausal women aged 18-44 y undergoing laparoscopies and laparotomies at 14 clinical sites between 2007 and 2009 and a general population sample of 131 women from the same geographic area who were matched on age and menstruation status. Endometriosis in the surgical sample was assessed by surgical visualization (clinical gold standard), whereas disease in the general population sample was assessed with the use of a pelvic MRI. Urine concentrations of genistein, daidzen, O-desmethylangolensin, equol, enterodiol, and enterolactone were measured at baseline. Poisson regression with robust error variance was used to estimate the risk of an endometriosis diagnosis for each sample after adjusting for age and body mass index (in kg/m²). Separate models were run for each phytoestrogen.

RESULTS

Overall geometric mean urine concentrations of phytoestrogens were as follows: genistein [88 nmol/L (95% CI: 72, 108 nmol/L)], daidzein [194 nmol/L (95% CI: 160, 236 nmol/L)], O-desmethylangolensin [4 nmol/L (95% CI: 3, 6 nmol/L)], equol [4 nmol/L (95% CI: 4, 6 nmol/L)], enterodiol [29 nmol/L (95% CI: 22, 38 nmol/L)], and enterolactone [355 nmol/L (95% CI: 395, 544 nmol/L)]. Geometric mean concentrations of phytoestrogens did not significantly differ by endometriosis status in either sample. Adjusted RRs for endometriosis ranged from 0.87 to 1.09 for the 6 phytoestrogens measured, with all CIs including a value ≥1. Phytoestrogens were not associated with the severity of endometriosis when restricting the analysis to women with moderate-to-severe disease per the revised American Society for Reproductive Medicine criteria. Furthermore, no associations were observed between self-reported high soy intake and endometriosis.

CONCLUSIONS

Despite endometriosis being an estrogen-dependent disease, we found no evidence that urinary phytoestrogens were associated with a higher risk of an endometriosis diagnosis in either a sample of premenopausal women or in a surgical sample.

Research Priorities for Endometriosis

The 3rd International Consensus Workshop on Research Priorities in Endometriosis was held in São Paulo on May 4, 2014, following the 12th World Congress on Endometriosis. The workshop was attended by 60 participants from 19 countries and was divided into 5 main sessions covering pathogenesis/pathophysiology, symptoms, diagnosis/classification/prognosis, disease/symptom management, and research policy. This research priorities consensus statement builds on earlier efforts to develop research directions for endometriosis. Of the 56 research recommendations from the 2011 meeting in Montpellier, a total of 41 remained unchanged, 13 were updated, and 2 were deemed to be completed. Fifty-three new research recommendations were made at the 2014 meeting in Sao Paulo, which in addition to the 13 updated recommendations resulted in a total of 66 new recommendations for research. The research recommendations published herein, as well as those from the 2 previous papers from international consensus workshops, are an attempt to promote high-quality research in endometriosis by identifying and agreeing on key issues that require investigation. New areas included in the 2014 recommendations include infertility, patient stratification, and research in emerging nations, in addition to an increased focus on translational research. A revised and updated set of research priorities that builds on this document will be developed at the 13th World Congress on Endometriosis to be held on May 17-20, 2017, in Vancouver, British Columbia, Canada.

Endometriosis: where are we and where are we going?

Endometriosis currently affects ~5.5 million reproductive-aged women in the U.S. with symptoms such as painful periods (dysmenorrhea), chronic pelvic pain, pain with intercourse (dyspareunia), and infertility. It is defined as the presence of endometrial tissue outside the uterine cavity and is found predominately attached to sites within the peritoneal cavity. Diagnosis for endometriosis is solely made through surgery as no consistent biomarkers for disease diagnosis exist. There is no cure for endometriosis and treatments only target symptoms and not the underlying mechanism(s) of disease. The nature of individual predisposing factors or inherent defects in the endometrium, immune system, and/or peritoneal cavity of women with endometriosis remains unclear. The literature over the last 5 years (2010-2015) has advanced our critical knowledge related to hormones, hormone receptors, immune dysregulation, hormonal treatments, and the transformation of endometriosis to ovarian cancer. In this review, we cover the aforementioned topics with the goal of providing the reader an overview and related references for further study to highlight the progress made in endometriosis research, while concluding with critical areas of endometriosis research that are urgently needed.