This topic encompasses the literature trying to develop somewhat unified theories of the disease, that is to say, to provide a generalist explanation for the emergence and continuation of the illness, potentially combining different mechanisms (see for instance Sourial et al., 2014 for a review). Notable examples include the retrograde menstruation theory, developed in the 1920s by Sampson. This theory’s primary mechanism is that menstrual flow going “backwards” towards the fallopian tubes carries debris of the endometrium. These debris can then implant themselves in abnormal spots outside the uterus and cause symptoms. Other notable theories include metaplasia theory (cells outside the uterus transform themselves into strange cells resembling the endometrium, causing issues) and induction theory (a hybrid theory). All these theories have advantages and drawbacks because they explain some aspects of reality well and tend to have gaps in others. For instance, retrograde menstruation occurs in most women, and the majority does not develop endometriosis. As endometriosis is very diverse, it is also likely that the causes are not the same depending on each patient.
This topic has tended to decline in relative importance since the early 20th century. It could be interpreted as the fact that devising general theories is quite challenging and that the research is getting more specialized into specific aspects and mechanisms.
Recent examples of highly cited publications contributing to this topic are:
This topic is very heterogeneous and thus difficult to describe. It regroups publications analyzing various mechanisms at play in the emergence, diffusion and evolution of endometriosis. As such, it contains research on cells involved in endometriosis (their characteristics, mechanisms of proliferation, diffusion and death), oxidative stress or blood-related issues. It also builds heavily upon animal models' findings, that is, experiments with animals (hopefully) mimicking what happens in humans (e.g., rats, mice, monkeys…). There may be overlaps with other topics, especially those related to hormones or the immune system. Consequently, this topic should be interpreted as a mixed bag focusing on biological issues.
This topic is very important quantitatively, as it is the largest in recent decades, and it has also benefited from substantial growth since the 1980s.
Recent examples of highly cited publications contributing to this topic are:
Hormones are molecules that transfer information across the body, leading to changes in physiological or behavioral activities (e.g., metabolism, sleep, lactation, reproduction…). They are notably involved in the production of eggs, pregnancy and menstruation. It is clear that hormones, particularly steroid hormones (including sex hormones such as estrogen and progesterone), have a major role in endometriosis (See for instance Barbosa et al, 2011). Abnormal endometriosis cells outside the uterus indeed depend on hormonal levels (e.g., for their growth) and react to them. Findings are however complex and sometimes conflicting. This strand of research thus aims at understanding the role of hormones (mainly estrogen and progesterone) in the disease and how they interact with other causes or mechanisms, such as genetics or the immune system.
Surprisingly, this topic is modest quantitatively and has faced relative decline since the 1980s. However, other topics also cover hormonal aspects, especially treatment-related ones (which often act on hormones), stressing their importance in endometriosis research.
Recent examples of highly cited publications contributing to this topic are:
Inflammation is a reaction of the immune system to various threats identified in the body. Its main goal is to contribute to their elimination. Endometriosis entails chronic inflammation because abnormal cells outside the uterus trigger this phenomenon, causing symptoms such as pain (See for instance University of Edinburgh, 2021). Moreover, there is evidence that people with endometriosis may have abnormal immune system responses – regarding their activation and abilities to eliminate the abnormal cells for instance. This topic of the literature thus targets an understanding of the linkages between the immune system and endometriosis, as well as the effects of the resulting inflammation.
This topic is relatively modest quantitatively and has experienced a slight relative decline since the 1990s-2000s.
Recent examples of highly cited publications contributing to this topic are:
Endometriosis has a clear genetic dimension, as demonstrated by its tendency to run in families. However, there is no single gene of endometriosis that would cause the disease in all cases, nor it is inevitable that daughters of affected women will also have the condition. Instead, many genes likely produce some increases in risk, making endometriosis a polygenic disease. This topic of research is concerned with identifying the many genes that could be involved in endometriosis, how they are expressed and regulated (i.e., how the information carried by the gene leads to actual changes in the body) and how they depend on external factors (See Bischoff et al., 2008 for more details). It is performed through different types of studies, such as family studies or Genome-Wide Association Studies (large-scale statistical comparisons of genes of people with and without the illness).
This topic is an emerging subject with notable growth over the recent years. It is notably linked to advances in techniques to study genes.
Recent examples of highly cited publications contributing to this topic are:
Another approach to identifying potential causes and mechanisms of endometriosis is to adopt an epidemiological perspective. Using statistics, it is possible to identify factors “increasing” or “decreasing” the risk to develop the disease or its outcomes. This strand of research often results in “associations” that must be interpreted with caution. They are not necessarily causes as such because several factors may be missing from the analysis. Combined with other sources of evidence (for instance, on the biological mechanisms at play), they can however hint towards potential causes and guide interventions. For example, there have been many studies trying to find environmental (e.g., pollutants such as phthalates, metals…), dietary, occupational (e.g., night shifts), or demographic factors (e.g., age, obesity…) linked to endometriosis. Some factors are well-established as being associated with an increased risk, such as low weight or short menstrual cycles. However, many findings on this topic are still mixed and require additional research.
This topic represents a sizeable share of the research output and tends to be dynamic. However, the methodological quality of several studies (and their press coverage) can be questionable. It is debatable whether this detailed topic should be classified under the broad category “1. Causes and mechanisms”, as it could also be linked to the epidemiological issues highlighted in “7. Health and economic burden”.
Recent examples of highly cited publications contributing to this topic are:
This topic aims to describe the anatomical features of endometriosis, covering the different types of endometriosis lesions (e.g., appearance, cell-types/composition…), their locations, and connections to symptoms. It is pretty connected to surgical issues and notably targets pelvic endometriosis (the most common form). It is thus more generalist than the detailed topic dedicated to describing specific subtypes.
This topic used to constitute a significant share of the entire scientific output in the early 20th century, but its relative importance has gradually reduced to much lower levels. In recent years, it remains of moderate importance (i.e., about 3% of the content in the 2010s-2020s).
Recent examples of highly cited publications contributing to this topic are:
Creating classifications may seem very technical, but this has critical practical ramifications. Such classifications allow the distinction between the different forms of the disease, insights on its impacts (for instance, on fertility), its severity and prognosis. Based on this information, the ambition is to allow more advanced research and adapt treatments. Notable examples of classifications include the ASRM (American Society for Reproductive Medicine) staging system or the EFI (Endometriosis Fertility Index). They are often debated regarding their relevance, performance and diffusion among medical practitioners. For example, the ASRM has a very poor predictive value regarding symptoms but is still widely used. By contrast, the EFI is adequate to predict fertility outcomes (See Capezzuoli et al., 2020). This strand of the literature thus aims to develop and test these classification systems and use them for concrete research applications.
This topic represents a moderate share of the total research output and has been relatively stable for a few decades. It might be because all sorts of research rely on such classification effort, even when it is not the core subject of the publications.
Recent examples of highly cited publications contributing to this topic are:
Beyond the broad classification systems and distinctions developed in the previous topic, there is also an extensive research program focusing on the description of subtypes of endometriosis. This topic entails the provision of anatomical details on the different forms of endometriosis, with their characteristic lesions. It includes adenomyosis (a form of endometriosis that is “internal” to the uterus), superficial peritoneal endometriosis, ovarian endometriosis (with cysts), various forms of deep infiltrating endometriosis (e.g., bladder, rectal…) or even rarer subtypes (such as pulmonary endometriosis). This topic is thus very relevant to surgical aspects of the disease.
This topic is highly significant on quantitative grounds, probably highlighting the influence of surgeons in endometriosis research. However, it has experienced a relative decline over time as a share of total output, reaching about 6% of the production in recent decades. It is also often combined with other topics.
Recent examples of highly cited publications contributing to this topic are:
Endometriosis is a very heterogeneous disease, with symptoms and signs going far beyond the “classic” issues of pain and infertility. Obtaining an overview of the clinical features and presentation of patients is thus valuable, especially to facilitate the diagnosis. This topic addresses this issue while also highlighting the specificities of some subgroups (e.g., adolescents, young adults…).
This generalist topic has been relatively stable in terms of quantitative importance for a few decades, albeit at a very low level. This topic is often combined in specific publications with insights on diagnosis or treatment, where it acts as an introductory element.
Recent examples of highly cited publications contributing to this topic are:
Pain is often presented as the primary symptom of endometriosis alongside fertility issues. It is indeed a leading cause of suffering and reduced quality of life for patients. Identifying endometriosis pain and understanding its mechanisms are thus critical for managing the disease. It can facilitate the diagnosis, the research of treatment and the adaptation of care to specific women. Therefore, this topic investigates pain-related issues, distinguishing different types of pain (e.g., chronic pelvic pain, pain during periods, pain during sex, etc.). It uncovers the biological basis of pain, such as the role played by nerves. It also intends to improve the evaluation of endometriosis pain (for instance, through the design of adapted scales to assess it).
This topic benefits from a moderate share of the research output linked to endometriosis, which may be somewhat surprising given its centrality in symptoms. However, it should be noted that its relative importance has grown significantly since the 1980s. Moreover, pain is also partially covered by treatment-related detailed topics, as this symptom is a major target in healthcare.
Recent examples of highly cited publications contributing to this topic are:
As a hormone-dependent disease, endometriosis is strongly connected to the menstrual cycle. Different symptoms, for instance, pain, are typically enhanced during menstruation. This topic is thus interrelated to the previous one on pain but is dedicated to the menstrual cycles' own characteristics. In particular, it explores the length, regularity and bleeding patterns of the menstrual cycles.
This detailed topic is relatively minor on quantitative grounds and has also steadily declined since the 1950s. The low share of the scientific output specifically dedicated to menses should, however, be nuanced because it is interrelated with other detailed topics (e.g., pain).
Recent examples of highly cited publications contributing to this topic are:
Alongside pain, fertility-related issues are the other canonical symptom of endometriosis and a leading cause of patients seeking medical care. The illness can indeed reduce the likelihood of pregnancy – though the risk varies greatly between individuals and can often be tackled in some ways. This topic thus focuses on explaining these fertility issues, exploring different possible mechanisms such as pelvic anatomy, hormonal aspects or ovulatory function (See Bulletti et al., 2010). The topic also investigates the possible outcomes of pregnancies in women with endometriosis, including the risk of miscarriage.
Fertility has been a critical concern of medical doctors studying the disease for a long time and is also linked to social aspects. It has thus been strongly emphasized in the literature, though it has been relatively stable in importance for a few decades. Moreover, many treatments are geared towards improving fertility outcomes, further stressing the real importance of this theme beyond this specific topic.
Recent examples of highly cited publications contributing to this topic are:
Endometriosis is not restricted to “purely medical” symptoms. Instead, it has significant impacts on the daily life and experience of patients. This strand of the literature has gained traction recently and attempts at complementing the traditional picture of symptoms with extended feedback from affected women. It places a higher emphasis on qualitative evidence and psychological/social aspects. It thus explores themes such as quality of life, work, intimate relationships, sex but also the experience of patients with the healthcare system (consent, information…).
As previously mentioned, this topic has experienced high growth in recent decades, reaching moderate levels of importance in the 2020s. It can perhaps be linked to a greater emphasis on quality of life and patients' influence on research priorities.
Recent examples of highly cited publications contributing to this topic are:
Successfully diagnosing endometriosis is not only a matter of developing different types of relevant tests (e.g., imaging, surgical operations…). These tools must indeed contribute to a broader strategy and consider multiple vital issues. This topic is thus a generalist one that deals with diagnosis issues, such as the clinical examination of patients. It also reflects upon diagnosis challenges (e.g., multiple forms of symptoms, existence of severe diagnosis delays…) and the performance of tests (comparative performance, accuracy…) covering surgical, imaging and biological ones.
In line with the importance of transversal diagnosis issues, this topic covers a moderate share of the research output and has been relatively stable in recent decades.
Recent examples of highly cited publications contributing to this topic are:
The standard definition of endometriosis is based on the presence of tissue resembling the endometrium outside the uterus. In line with this definition, a major tool to diagnose the disease is exploratory surgery, where doctors can see these lesions (e.g., cysts on the ovaries, pelvic adhesions, etc.). It is notably performed through a procedure called laparoscopy, using a camera and tiny incisions. It also entails biopsies and histological analyses of the recovered tissues for confirmation. This topic explores these surgical issues, focusing on the different available procedures and their contribution to diagnosis.
This topic only represents a minimal share of the total scientific output. It has also been declining for a few decades. However, it must be reminded that it is only concerned with surgical diagnosis, and surgery is also used for treatment, boosting its overall contribution to the literature.
Recent examples of highly cited publications contributing to this topic are:
Even if the standard approach to fully confirm endometriosis is surgical exploration, tests based on medical imaging play a crucial role in detecting the disease at different stages. They can indeed be mobilized to obtain information on the various lesions, check their consistency with endometriosis/other conditions, and prepare surgical treatments (See Mayo Clinic, 2018). Many medical imaging tests are available, each with specific applications for endometriosis diagnosis. It includes ultrasonography or MRI. This strand of the literature investigates these different medical imaging techniques in their ability to detect endometriosis.
This topic constitutes a moderate share of the literature and has tended to consolidate over time, growing slowly but steadily. Through medical progress, it has, for instance, incorporated an ever-increasing number of imaging techniques.
Recent examples of highly cited publications contributing to this topic are:
Biological markers (or biomarkers in short) are a set of medical signs, i.e., “objective indications of medical state observed from outside the patient – which can be measured accurately and reproducibly” (Definition from Strimbu et al., 2011). It can refer to anything measurable (e.g., molecules in the blood, the peritoneal fluid, etc.) in patients that can be reliably linked to endometriosis. They offer the opportunity to devise a non-invasive diagnosis test (unlike surgery). However, despite the significant efforts carried out for decades, no biomarker suitable to clinical settings has been found yet for endometriosis. This strand of research thus focuses on developing and testing such markers. This topic is also concerned with broader biological or chemical analyses that are useful in studying the illness.
This topic is important on quantitative grounds, owing to the efforts to develop reliable biomarkers and the centrality of various analyses performed to understand the disease on broader grounds. It has however slightly declined in recent decades.
Recent examples of highly cited publications contributing to this topic are:
Providing an adequate treatment is not simply about having the suitable options at disposal (e.g., specific drugs or surgical techniques) but also about adopting a relevant therapeutic approach focused on the needs of each patient. It entails balancing the benefits and risks of available options, anticipating potential outcomes, addressing difficulties and considering long-term issues (e.g., follow-up). This topic explores these broad therapeutical issues at the center of clinical decisions, for instance, by developing guidelines or recommendations regarding treatment.
This topic is of moderate importance quantitatively and can be linked to evidence-based medicine practices, with a critical emphasis put on clinical guidelines, consensus statements based on scientific findings regarding treatments, etc. It has slightly declined in recent decades.
Recent examples of highly cited publications contributing to this topic are:
As of today, there is no definite cure for endometriosis, but symptoms can be significantly improved by using drugs or surgery. In particular, medications can help alleviate pain and avoid fertility issues linked to the progression of the disease over time. Since endometriosis reacts to hormonal changes, an essential focus of the medical approach to treating the illness has focused on hormonal treatments (e.g., contraceptives, Gonadotropin-releasing hormone agonists and antagonists that affect the hormones modulating the activity of the ovaries, aromatase inhibitors which influence the levels of estrogens…). Some non-hormonal drugs are also critical to tackling the disease (e.g., painkillers…). This strand of the literature deals with the discovery, analysis of the effects (e.g., risks and benefits, adaptation to different cases…) and use of all types of drugs.
This topic is essential quantitatively as a testimony of the critical role of drugs in the management of endometriosis. It is also probably increasing in diversity, with emerging research on non-hormonal treatments over time. Its relative importance has however declined since its peak in the 1980s.
Recent examples of highly cited publications contributing to this topic are:
A long-lasting concern with endometriosis is its potential impact on fertility, as it can reduce the likelihood of pregnancy. Several technologies and related practices have emerged to mitigate this risk and increase pregnancy chances. It consists of various fertility-enhancing treatments (e.g., ovarian stimulation) and notably In Vitro Fertilization (IVF – regrouping multiple approaches). It should be noted that the applicability and success of these techniques can be mixed, depending on numerous factors. This topic of the literature thus aims to develop these treatments and analyze their potential outcomes (particularly the success rates in terms of pregnancies).
By itself, this specific topic is only of modest importance and has tended to stagnate in the past three decades. However, other detailed topics also tackle fertility aspects, as other treatments (including drugs and surgery) can address this issue. Its weight in the literature shall thus be interpreted with caution.
Recent examples of highly cited publications contributing to this topic are:
As stated previously, surgery is a standard treatment approach for endometriosis-related pain and infertility. Several strategies and techniques are possible, but they share a series of common issues. This topic is thus rather generalist and aims at providing an overview of several of these surgical issues. It entails reflections on the surgical management of the disease and its connection to the broader treatment strategy. It also explores the critical conditions to successful surgeries (e.g., team’s skills, operation-related health problems, pre-surgical approach…). Last but not least, it deals with the follow-ups of operations and the risk of recurrence, which can be high after surgery.
This topic is of modest importance quantitatively but has experienced slow and steady growth for a very long time. It is obviously strongly connected to the topic dealing with specific surgical techniques.
Recent examples of highly cited publications contributing to this topic are:
As a central treatment option to alleviate the symptoms of endometriosis, surgery can take multiple forms depending on the types (cysts, adhesions…), severity and location of lesions (e.g., peritoneal, deep endometriosis…). It includes conservative surgery (to remove endometriosis deposits) or more radical procedures (e.g., removing the uterus or the ovaries). Most operations use a laparoscopic approach, where a small tube with a camera and light source is inserted in the abdomen or pelvis, avoiding large incisions. Recent developments have also included robotic surgery. This topic explores the different techniques available, including their realm of application, the method to carry out the procedures and their effects/risks.
As a standard treatment of endometriosis, this topic has high quantitative importance, and it has been relatively stable over the last few decades. It is connected to various other topics, including the one outlining general surgical issues.
Recent examples of highly cited publications contributing to this topic are:
This last topic among treatments is a residual category, meaning that it regroups a very heterogeneous set of options not covered in other categories. It encapsulates investigations on Intra-Uterine Devices, combinations of some drugs and surgery, specific drugs (e.g., some painkillers, vitamins), but also alternative and complementary medicine.
This topic remains modest quantitatively despite steady long-term growth. Moreover, given the fact that this is a mixed bag of heterogeneous interventions, interpreting this trend is tricky.
Recent examples of highly cited publications contributing to this topic are:
A bulk of the research on the connections between endometriosis and other diseases focuses on cancer and other tumors (e.g., uterine fibroids). Endometriosis is linked to abnormal growth of cells where they should not be but is not cancerous. However, there can be similarities in mechanisms, symptoms, and signs for diagnosis, making it relevant to conduct studies to appropriately understand the potential linkages between these conditions. Moreover, it has been debated for a long time whether endometriosis could increase (or decrease) the risks for some cancers (e.g., ovarian, endometrial…) or other tumors. Indeed, some studies show associations, but causality remains to be entirely ascertained. This strand of the literature thus explores these issues.
Cancers and tumors are a severe health concern overall, which explains the importance of this topic on quantitative grounds. However, it has tended to face a reduction in relative importance since the 1970s.
Recent examples of highly cited publications contributing to this topic are:
Beyond cancer and other tumors, endometriosis can have linkages to other gynecological conditions. In particular, they can be comorbidities associated with endometriosis. This topic explores such links, incorporating illnesses such as Polycystic Ovarian Syndrome, STDs/infections and a series of gynecological anomalies (e.g., malformations of the uterus…).
This detailed topic is now of modest importance, following a long-term period of decline. In recent decades, it has tended to stagnate at similar levels.
Recent examples of highly cited publications contributing to this topic are:
Last but not least, this topic investigates the connections of endometriosis with various diseases and health issues that do not strictly fall under the previous categories. In practice, it focuses on the comorbidities of endometriosis, primarily the psychiatric ones but not exclusively (e.g., neurological issues, heart and circulatory problems, etc.). It should be noted that this research strand is not an attempt at psychologizing endometriosis but is instead concerned with the psychological effects of the disease (anxiety, depression…).
This topic has been of moderate importance in recent decades, after having steadily declined for a long time. However, given its residual nature, it is challenging to interpret this dynamic accurately.
Recent examples of highly cited publications contributing to this topic are:
Epidemiology is the study of health and diseases at the population level. In the context of this analysis, its contributions are spread out across different topics (e.g., in the risk factors of the broad topic on “causes and mechanisms”). However, one of its primary roles is to assess how common endometriosis is (prevalence and incidence), which is central to understanding the burden of this disease. This task is complicated by the challenges of diagnosing endometriosis accurately. This topic thus aims to improve our knowledge of the weight of endometriosis in different populations. It also deals with related epidemiological issues not covered in other topics.
This topic is only a minor one in quantitative terms but has experienced dynamic growth since the 1990s. Moreover, as previously mentioned, epidemiological evidence is also covered in other detailed topics, mainly the one dedicated to risk factors in the “causes and mechanisms” broad topic. So the actual weight of epidemiology in the endometriosis R&D is more extensive than what the figure for this single topic may suggest.
Recent examples of highly cited publications contributing to this topic are:
Endometriosis leads to critical economic burdens. There are different perspectives to think about this issue. At the individual level, endometriosis yields missed opportunities regarding education, work and induces direct costs due to treatments. At the social level, society dedicates resources to tackle endometriosis (e.g., through the healthcare or welfare systems) and would benefit economically from more healthy people. Finally, stakeholders must optimize the available resources in the healthcare system to obtain the best health outcomes. The economic literature on endometriosis is mainly concerned with exploring and assessing these different issues. Its insights can be helpful to reflect on the “fair” amount of resources that should be channeled to fight endometriosis. Even if there are uncertainties on the exact economic burden of endometriosis, it is clear that it would be beneficial to dedicate much more funding to the disease.
This detailed topic is very marginal, accounting for only 0.4% of the abstracts’ content in the 2010s. However, it has benefited from fast growth since the 1990s. The diversification of endometriosis R&D from that decade onwards can explain this dynamic.
Recent examples of highly cited publications contributing to this topic are:
As surprising as it may seem, there are papers on scientific research itself. It allows scientists to reflect on the state of endometriosis research (its past, its achievements and issues) and to set priorities for the future. As a consequence, it can be quite influential in shaping future findings. This topic focuses on this strand of the literature, including publications such as consensus statements of scientific groups/congresses.
This detailed topic is a minor one based on quantitative weight, even though it can be influential in shaping future scientific developments. It has slightly grown for the past few decades.
Recent examples of highly cited publications contributing to this topic are:
This topic deals with veterinary-related issues, which are slightly different from animal models to study endometriosis in humans. In particular, the main focus of this strand of research is dairy cows, which can be affected by conditions resembling endometriosis or others linked to their reproductive system. The ambition is to increase animal welfare and to avoid losses in production. This topic also investigates endometriosis in other animals, such as mares, guinea pigs...
This topic is a niche one, explaining its meager share of total endometriosis-related research.
Recent examples of highly cited publications contributing to this topic are:
One of the dominant topics within the endometriosis literature attempts at uncovering the origins and underlying mechanisms connected to the disease. It focuses on the factors leading to the illness and the mechanisms sustaining its evolution and progression. It is highly diversified as it encapsulates several biological aspects (from hormones to genetics) but also more abstract approaches, such as statistical analysis of risk factors. A core idea underpinning this broad topic is that understanding these origins and mechanisms could help us to intervene by proposing treatments targeting the identified causes.
This broad topic constitutes a moderate share of the scientific output and has declined in relative importance in the literature over time. However, it is of the uttermost importance as it is concerned with the anatomical description of endometriosis (e.g., its different lesions). It also encapsulates research developing the various classification systems to be applied to the disease (e.g., severity, subtypes). Consequently, the categories created by this strand of research have a strong practical influence on both research and healthcare.
Perhaps surprisingly, the broad topic specifically dedicated to symptoms, signs and the daily experience linked to the disease only represents a moderate share of the total research output. However, it has tended to grow in relative importance over time. Moreover, the research dedicated to treatment also covers and addresses symptoms, which nuances this relatively small specialized share. As the symptoms of endometriosis can take various forms and severity, this broad topic is composed of several more detailed ones. This strand of research is helpful to diagnose patients, adapt their treatments and reflect on their subjective experiences.
Endometriosis is notoriously difficult to diagnose, leading to significant delays in accessing adapted treatments for patients. This situation results from multiple factors, including the normalization of pain by women and medical professionals, but also the issues with existing tests and analyses. Indeed, the convenience and reliability of tests and analyses for endometriosis are not always excellent. The gold standard procedure to confirm the disease remains a surgical exploration of the body, even if medical imaging techniques are also routinely used. This topic is thus concerned with the diagnosis issues surrounding endometriosis, which includes the development of diagnosis tests/analyses, their evaluation and their role within a broader healthcare strategy. Overall, a moderate effort is dedicated to this broad topic in the literature. It has risen in the long term but has experienced a slight relative decline since the 2000s.
At this stage, there is unfortunately no definitive cure for endometriosis. However, there are various treatment options available to reduce the main symptoms of the disease, notably pain and infertility. Their relevance depends on the specific situation and preferences of the patient. This strand of the literature aims at exploring all the issues related to treatment, from their development and test (e.g., drugs, surgery…) to broader considerations on how to organize their use. It is obviously one of the dominant broad topics quantitively, in line with the essential needs for care improvement.
Endometriosis shares some connections to other diseases. Concretely, it can happen through two main distinct situations. On the one hand, endometriosis can present some similarities with other illnesses, making it challenging to distinguish it and diagnose it reliably. On the other hand, other diseases can coincide with endometriosis (e.g., because of increased risk), that is to say, they are comorbidities. This broad topic thus documents several aspects of these potential connections. As such, it incorporates scientific publications whose primary focus is not necessarily endometriosis (e.g., cancer research). It represents a moderate share of the studied literature, with a notable decline over time. It may suggest an increasing emergence of endometriosis as a self-standing topic in the scientific literature in recent decades.
Endometriosis is a common disease worldwide, affecting a significant share of women (probably 5-10%). It also has substantial negative economic impacts, both at the individual and social level (e.g., due to health costs but also difficulties regarding education or work). These health and economic dimensions constitute the “burden” of endometriosis, but its exact scope remains to be fully explored. This broad topic is thus concerned with these aspects. It represents only a minor, though increasing, share of the research output.
This ultimate broad topic is a residual category covering all the issues that could not be included elsewhere. It encapsulates a meta-reflection on endometriosis research itself but also insights for farm animals potentially affected by endometriosis. The quantitative importance of this broad topic is minimal compared to others.
