Risk Factors for Endometriosis in a German Case-Control Study

Pregnancy-related complications in patients with endometriosis in different stages

BACKGROUND

Endometriosis is one of the most common and costly diseases among women. This study was carried out to investigate pregnancy outcomes in women with endometriosis because of the high prevalence of endometriosis in reproductive ages and its effect on pregnancy-related complications outcomes.

METHODS

This was a cross-sectional study performed on 379 pregnant women with endometriosis who were referred to the endometriosis clinic of the Avicenna Infertility Treatment Center from 2014 to 2020. Maternal and neonatal outcomes were assessed for the endometriosis group and healthy mothers. The group with endometriosis was further divided into two groups: those who underwent surgery and those who either received medication alone or were left untreated before becoming pregnant. The analysis of the data was done using SPSS 18.

RESULTS

The mean age of the patients was 33.65 ± 7.9 years. The frequency of endometriosis stage (P = 0.622) and surgery (P = 0.400) in different age groups were not statistically significant. The highest rates of RIF and infertility were in stages 3 (N = 46, 17.2%) (P = 0.067), and 4 (N = 129, 48.3%) (P = 0.073), respectively, but these differences were not statistically different, and the highest rate of pregnancy with ART/spontaneous pregnancy was observed in stage 4 without significant differences (P = 0.259). Besides, the frequency of clinical/ectopic pregnancy and cesarean section was not statistically different across stages (P > 0.05). There is no significant relationship between endometriosis surgery and infertility (P = 0.089) and RIF (P = 0.232). Most of the people who had endometriosis surgery with assisted reproductive methods got pregnant, and this relationship was statistically significant (P = 0.002) in which 77.1% (N = 138) of ART and 63% (N = 264) of spontaneous pregnancies were reported in patients with endometriosis surgery. The rate of live births (59.4%) was not statistically significant for different endometriosis stages (P = 0.638). There was no stillbirth or neonatal death in this study. All cases with preeclampsia (N = 5) were reported in stage 4. 66.7% (N = 8) of the preterm labor was in stage 4 and 33.3% (N = 4) was in stage 3 (P = 0.005). Antepartum bleeding, antepartum hospital admission, preterm labor, gestational diabetes, gestational hypertension, abortion, placental complications and NICU admission were higher in stage 4, but this difference had no statistical difference.

CONCLUSION

Endometriosis is significantly correlated with infertility. The highest rates of RIF and infertility are observed in stages 3 and 4 of endometriosis. The rate of pregnancy with ART/spontaneous pregnancy, preterm labor, preeclampsia and pregnancy-related complications is higher in stage 4. Most of the people who had endometriosis surgery with assisted reproductive methods got significantly pregnant. Clinical/ectopic pregnancy, cesarean sections, and live birth were not affected by the endometriosis stages.

The role of peroxisome proliferator-activated receptors in endometriosis

Endometriosis constitutes the most common cause of chronic pelvic pain in female patients and is associated with infertility. Although there is no known cause for the disease, it is a heritable condition that is determined by numerous genetic, epigenetic, and environmental aspects. Peroxisome proliferator-activated receptors (PPARs) represent nuclear receptor proteins that control gene expression. By using the MEDLINE and LIVIVO databases we conducted a literature review in order to look into the role of PPARs in the endometriosis pathophysiology and succeeded in revealing 36 pertinent publications between 2001 and 2022. In regards to PPAR expression in endometriosis, PPARγ seems to represent the most studied PPAR isoform in endometriosis and to influence various pathways involved in the disease onset and progression. It's interesting to note that diverse treatment agents targeting the PPAR system have been identified as innovative, effective therapeutic alternatives in the context of endometriosis treatment. In conclusion, PPARs appear to contribute an important role in both endometriosis pathophysiology and therapy.

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.

Comprehensive characterization of endometriosis patients and disease patterns in a large clinical cohort

PURPOSE

In many diseases, it is possible to classify a heterogeneous group into subgroups relative to tumor biology, genetic variations, or clinical and pathological features. No such classification is available for endometriosis. In our retrospective case-case analysis we defined subgroups of endometriosis patients relative to the type and location of the endometriosis lesion and relative to basic patient characteristics.

METHODS

From June 2013 to July 2017, a total of 1576 patients with endometriosis diagnosed at surgery were included in this study. The patients' history and clinical data were documented using a web-based remote data entry system. To build subgroups, all possible combinations of endometriosis locations/types (peritoneal; ovarian endometriosis; deeply infiltrating endometriosis; adenomyosis) were used. Due to the variation in group sizes, they were combined into five substantial larger groups.

RESULTS

Age, pregnancy rate, and live birth rate were identified as characteristics that significantly differed between the five patient groups that were defined. No significant differences were noted in relation to body mass index, length of menstrual cycle, age at menarche, reason for presentation, or educational level.

CONCLUSION

This study describes basic patient characteristics in relation to common clinical subgroups in a large clinical cohort of endometriosis patients. Epidemiological information about different clinical groups may be helpful in identifying groups with specific clinical courses, potentially suggesting novel approaches to early detection and to surgical and systemic treatment.

Association between body mass index and endometriosis risk: a meta-analysis

Background

Epidemiological studies have sought to establish a relationship between a woman's current body mass index and endometriosis, but with varying results. This meta-analysis was to summarize the current epidemiological evidence.

Methods

Pertinent studies were identified by searching PubMed and Web of Science through November 2016. Study-specific risk estimates were combined using fixed or random effects models depending on whether significant heterogeneity was detected.

Results

A total of 11 studies (two cohort studies and nine case-control studies) was included in the meta-analysis. The pooled relative risk of endometriosis was 0.67 (95% CI: 0.53, 0.84) for each 5 kg/m² increase in current body mass index, with statistical significant heterogeneity across the studies (P <0.001, I² =86.9%). Compared with normal weight women, the pooled relative risk for obese women was 0.89 (95% CI: 0.83, 0.96), which was lower than that for overweight women (relative risk =0.97; 95% CI: 0.91, 1.05). The combined estimate was robust across subgroup and sensitivity analyses and no observed publication bias was detected.

Conclusion

This study suggested that higher body mass index may be associated with lower risk of endometriosis. Further work will need to focus on elucidating underlying biologic mechanism that contribute to the initiation of endometriosis.

Increased serum levels of mBDNF in women with minimal and mild endometriosis have no predictive power for the disease

The objective of our pilot clinical, prospective study was to determine the serum levels of mature brain-derived neurotrophic factor, in of women with endometriosis and controls and explore whether mature brain-derived neurotrophic factor is a potential biomarker for the disease. The patients were selected from the Endometriosis Marker Austria prospective cohort study conducted at the tertiary referral certified Endometriosis Center of the Medical University of Vienna. All women underwent laparoscopic surgery because there was a suspicion of endometriosis, or the women had pelvic pain, adnexal cysts, unexplained infertility, or uterine fibroids. Our main outcome parameter was total levels of mature brain-derived neurotrophic factor in serum, measured using ELISA. Our results show that serum levels of mature brain-derived neurotrophic factor are significantly higher in women with endometriosis compared to women without endometriosis. The mean serum protein levels are significantly higher in women with rAFS stage I and II endometriosis, whereas no difference was found in women with stage III and IV endometriosis and controls. Postoperative follow-up at 6-10 weeks revealed that surgical intervention leads to equilibration of the levels of secreted mature brain-derived neurotrophic factor between women with and without endometriosis. The difference between serum mature brain-derived neurotrophic factor levels of women with endometriosis compared to women without endometriosis is independent of menstrual cycle phase and overall self-reported pelvic pain. ROC-curve analysis showed that, the mature brain-derived neurotrophic factor is not a useful biomarker for endometriosis. In conclusion, although women with stage I and II endometriosis have increased levels of mature brain-derived neurotrophic factor in serum compared to controls, the difference is not predictive for the disease. Impact statement Endometriosis is a disease that can have a significant impact on the quality of life of affected women. The gold standard for diagnosis to this day remains visualization through laparoscopic surgery with histological verification. Current studies are attempting to find a biomarker with high sensitivity and specificity, which would bypass the surgery-associated risks and would significantly reduce costs. In an attempt to elucidate whether mature serum BDNF can serve as diagnostic marker for the disease, we compared the levels of the protein in women with endometriosis to endometriosis-free controls. While our results showed that serum concentrations of the mature protein were significantly higher in women with endometriosis, we did not find this marker to have the sensitivity or specificity needed in order to allow a reliable diagnosis.

Efficacy of elagolix in the treatment of endometriosis

INTRODUCTION

Much research has gone into developing medications that can be used to alleviate endometriosis-associated symptoms. In addition to already established medications, a new GnRH antagonist, elagolix, is in development. The novelty of this drug compared to other GnRH antagonists, is its nonpeptide structure, allowing it to be administered orally. Areas covered: We analyzed several Phase I, II and III clinical trials that have evaluated the safety and efficacy of this new medication. Expert opinion: Since many medications have been put on the market and have gained popularity for the treatment of endometriosis-associated symptoms, the demonstration of equality or superiority of effect, tolerability, as well as patient compliance should be assessed when introducing a new drug. While elagolix may have an advantage over established GnRH agonists, in that it does not lead to a 'flare-up' effect, it too, takes a toll on bone mineral density. Nevertheless, studies have shown that this new oral GnRH antagonist is well tolerated, and the side effects have been described as 'mild or moderate'. However, in order to examine whether elagolix can compete with or even surpass established gold-standard medical treatments in this field, further studies that directly compare elagolix to said treatments, might be necessary.

The International Endometriosis Evaluation Program (IEEP Study) - A Systematic Study for Physicians, Researchers and Patients

INTRODUCTION

Endometriosis is a heterogeneous disease characterized by a range of different presentations. It is usually diagnosed when patients present with pain and/or infertility, but it has also been diagnosed in asymptomatic patients. Because of the different diagnostic approaches and diverse therapies, time to diagnosis can vary considerably and the definitive diagnosis may be delayed, with some cases not being diagnosed for several years. Endometriosis patients have many unmet needs. A systematic registration and follow-up of endometriosis patients could be useful to obtain an insight into the course of the disease. The validation of biomarkers could contribute to the development of diagnostic and predictive tests which could help select patients for surgical assessment earlier and offer better predictions about patients who might benefit from medical, surgical or other interventions. The aim is also to obtain a better understanding of the etiology, pathogenesis and progression of the disease.

MATERIAL AND METHODS

To do this, an online multicenter documentation system was introduced to facilitate the establishment of a prospective multicenter case-control study, the IEEP (International Endometriosis Evaluation Program) study. We report here on the first 696 patients with endometriosis included in the program between June 2013 and June 2015.

RESULTS

A documentation system was created, and the structure and course of the study were mapped out with regard to data collection and the collection of biomaterials.

CONCLUSION

The documentation system permits the history and clinical data of patients with endometriosis to be recorded. The IEEP combines this information with biomaterials and uses it for scientific studies. The recorded data can also be used to evaluate clinical quality control measures such as the certification parameters used by the EEL (European Endometriosis League) to assess certified endometriosis centers.

Endometriosis-associated Maternal Pregnancy Complications - Case Report and Literature Review

The incidence of endometriosis is increasing. Particularly during pregnancy and labour, clinicians should be alert to possible endometriosis-associated complications or complications of previous endometriosis treatment, despite a low relative risk. In addition to an increased rate of early miscarriage, complications such as spontaneous bowel perforation, rupture of ovarian cysts, uterine rupture and intraabdominal bleeding from decidualised endometriosis lesions or previous surgery are described in the literature. Unfavourable neonatal outcomes have also been discussed. We report on an irreducible ovarian torsion in the 16th week of pregnancy following extensive endometriosis surgery, and an intraabdominal haemorrhage due to endometriosis of the bowel in the 29th week of pregnancy.

Evaluation of the correlation between body mass index and endometriosis among Iranian fertile women

AIMS

The investigations have revealed an inverse correlation between body mass index (BMI) and endometriosis. Endometriosis is a common gynecological disease among women of reproductive age, which is defined as the implantation of endometrial glands and stroma outside the uterus. In this respect, we aimed to study the correlation between endometriosis and BMI in Iranian fertile women.

METHODS

In a case-control design, 46 fertile women with endometriosis and 53 matched controls were recruited. All of the patients had a laparoscopy or laparotomy surgery and histologically confirmed endometriosis. The control group was selected from healthy volunteers who referred to gynecologist for tubal ligation or surgery of benign gynecological diseases. The participants were interviewed based on a structured questionnaire which covered inquiries regarding demographics, reproductive and menstrual history.

RESULTS

Statistical analysis was performed by categorizing the BMI to four main groups: >30, 25-29.9, 18.5-24.9 and <18.5. The results showed a significant inverse correlation between BMI and endometriosis (p = 0.039). BMI over 30 was observed in 26% of healthy controls versus 13% of endometriosis patients. On the other hand, BMI under 18.5 were detected in 3 individuals, all of them belonged to the endometriosis group.

DISCUSSION

Recent investigations have emphasized the role of BMI in endometriosis. The results of this study suggest that lower BMI is associated with an increased risk of endometriosis. As a parameter easily obtained, BMI may be useful for risk assessment of endometriosis.

Inhibition of adhesion, proliferation, and invasion of primary endometriosis and endometrial stromal and ovarian carcinoma cells by a nonhyaluronan adhesion barrier gel

Endometriosis is a chronic disease of women in the reproductive age, defined as endometrial cells growing outside of the uterine cavity and associated with relapses. Relapses are hypothesized to correlate with incomplete surgical excision or result from nonrandom implantation of new endometrial implants in adjacent peritoneum. Thus, surgical excision could lead to free endometriotic cells or tissue residues, which readhere, grow, and invade into recurrent lesions. Barrier agents are frequently used to prevent postoperative adhesions. We tested if the absorbable cell adhesion barrier gel Intercoat consisting of polyethylene oxide and sodium carboxymethyl cellulose could inhibit cellular adhesion, proliferation, and invasion of primary endometriosis and endometrial cells. Due to an association of endometriosis with ovarian carcinoma, we tested two ovarian carcinoma cell lines. Prior to cell seeding, a drop of the barrier gel was placed in cell culture wells in order to test inhibition of adherence and proliferation or coated over a polymerized collagen gel to assay for prevention of invasion. Results showed that the barrier gel significantly inhibited cell adherence, proliferation, and invasion of endometriosis and endometrial stromal cells as well as ovarian carcinoma cells in culture. Our findings could help to prevent local cell growth/invasion and possible consequent recurrences.

Endometriosis: Survey of Current Diagnostic and Therapeutic Options and Latest Research Work

Endometriosis is one of the most frequent benign diseases in women of child-bearing age. The main symptoms are chronic upper abdominal pain and infertility. However, the aetiology and pathogenesis of endometriosis are as yet insufficiently clarified. Thus, therapy is mainly symptomatic with laparoscopic surgery being the gold standard. The aim of drug therapy is to achieve a hypo-oestrogenic condition. In cases of severe endometriosis and a desire to have children there is often an indication for assisted reproduction. The present article illustrates almost all current aspects on the diagnosis of and therapy of endometriosis. From the clinical viewpoint, emphasis is placed on the rare cases of deeply infiltrating endometriosis that are, however, accompanied with a high morbidity. Current therapeutic options in cases of infertility are also presented in more detail. Furthermore, special attention is paid to the latest research results from both clinical and basic research fields in order to demonstrate our current knowledge on the pathogenesis and, where possible, potentially related therapeutic options.

Cytotoxic T-Cells in Peripheral Blood in Women with Endometriosis

Aim: The etiology of endometriosis remains unknown, but increasing evidence suggests that immune regulation may be important. Our study aimed to evaluate peripheral blood lymphocyte subpopulations during the menstrual cycle in women with peritoneal and ovarian endometriosis relative to healthy women. Methods: In this study, 65 women with endometriosis (37 in the follicular phase and 28 in the luteal phase of the menstrual cycle) and 61 healthy women (33 in the follicular phase and 28 in the luteal phase) were enrolled. Flow cytometric analysis measured peripheral blood lymphocyte subpopulations. The serum levels of cortisol were also determined. Results: In healthy controls, we detected an increased concentration of cytotoxic (CD8⁺) T cells and activated (HLA-DR) T cells in the luteal phase compared with the follicular phase of the menstrual cycle (p = 0.020 and p = 0.045), whereas no such fluctuation was detected in endometriosis. However, a marked increase in regulatory T-cell concentration in the luteal phase was detected only in endometriosis patients (p = 0.005). Women with endometriosis had higher levels of serum cortisol (p = 0.022), which correlated with the concentration of regulatory T cells (p = 0.048). Conclusions: Women with endometriosis do not exhibit fluctuations in the concentrations of cytotoxic and activated peripheral blood lymphocytes during the menstrual cycle. The marked fluctuation of regulatory T cells detected in endometriosis could be attributed to altered immune response.

Endometrioma: From Pathogenesis to Clinical Management

An endometrioma (OMA) is the localization of endometriosis in ovary, and it most often develops as a cyst. The pathogenesis of OMA is still an open question and controversial; a cystic hemorrhagic corpus luteum may be a prerequisite, occurring as a transition to an endometriotic cyst. Inversion and progressive invagination of the ovarian cortex after the accumulation of menstrual debris derived from bleeding of superficial endometriotic implants, located on the ovarian surface and adherent to the peritoneum, is another hypothesis. Gene studies show that WNT4 and FN1 are predisposing genes for OMA development. A role of environmental toxicants in the development of OMA is also under investigation; dioxins and dioxin-like compounds (DLCs), interacting with steroid receptors, are possible factors. Even if women with endometriosis have a 1.5 times greater lifetime risk to develop an ovarian carcinoma, an OMA is not to be considered a preneoplastic lesion.

The clinical management of OMAs is complex and should be individualized. Ultrasounds and magnetic resonance imaging (MRI) are sensitive but not specific for diagnosis. Treatment is influenced by patient age, desire for pregnancy, pain severity, cyst dimensions and characteristics (unilateral/bilateral), coexistence of deep endometriosis, previous gynecological or obstetrical history and previous surgery. Laparoscopic surgery is considered the treatment of choice in cases of infertile patients with a large OMA or pain, and in patients not responding to medical therapy. It should be performed with proper techniques by trained surgeons to decrease the damage to the remaining ovarian tissue, and to maintain the ovarian reserve after surgery. A medical hormonal and nonhormonal treatment is used for asymptomatic and/or pain-associated OMA (progestins, estroprogestins and antiinflammatory drugs). Considering the relative high recurrence rate after surgery, a medical treatment should be offered.

Adenomyosis: Epidemiology, Risk Factors, Clinical Phenotype and Surgical and Interventional Alternatives to Hysterectomy

Adenomyosis is an important clinical challenge in gynecology and healthcare economics; in its fully developed form, hysterectomy is often used to treat it in premenopausal and perimenopausal women. Symptoms of adenomyosis typically include menorrhagia, pelvic pain and dysmenorrhea. Moreover, adenomyosis and leiomyomas commonly coexist in the same uterus, and differentiating the symptoms for each pathological process can be problematic. Although it has been recognized for over a century, reliable epidemiological studies on this condition are limited, because only postoperative diagnoses were possible in the past. Minimally invasive surgical techniques (endometrial ablation/resection, myometrial excision/reduction, myometrial electrocoagulation, uterine artery ligation) have had limited success in the treatment of adenomyosis, and the reported data for these procedures have been obtained from case reports or small case series with only short follow-up times. However, newer techniques including uterine artery embolization (UAE) and magnetic resonance imaging guided focused ultrasound (MRgFUS) show promise in treating adenomyosis. The data is strongest for UAE; these studies have the largest patient cohorts. However, none of the UAE studies were randomized or controlled. Thus, despite the clinical importance of adenomyosis, there is little evidence on which to base treatment decisions. The objective of this review is to summarize the epidemiology, risk factors, clinical phenotype and to evaluate the accrued experience with surgical and interventional alternatives to hysterectomy.

Endometriosis in adolescents is a hidden, progressive and severe disease that deserves attention, not just compassion

Endometriosis in the adolescent has, in recent years, been discovered to be a challenging problem in gynaecology. Although the pain may start at a young age, even before the onset of menstruation, the diagnosis by laparoscopy is almost always postponed for several years, by which time destructive lesions have affected the tubo-ovarian structures and severely compromised fecundability. Several factors may play a role, but one important reason for this disease progression is likely to be the delay in diagnosis. Therefore, transvaginal ultrasounds and transvaginal access with a less invasive needle endoscopy are recommended for exploration of the pelvis, diagnosis of endometriosis and treatment at an early stage before severe lesions develop.

Efficacy of the revised Enzian classification: a retrospective analysis. Does the revised Enzian classification solve the problem of duplicate classification in rASRM and Enzian?

PURPOSE

The most widely accepted classification for endometriosis is the Revised American Society for Reproductive Medicine (rASRM) system, but this does not take deeply infiltrating endometriosis (DIE) into account. The Enzian classification enables clinicians to classify DIE. Due to complexity and partial overlap with rASRM, it was revised for a second time in February 2011. Using both the systems to classify lesions would be inappropriate, as they refer to different locations. The aim of this study was to analyze whether the revised Enzian classification is easier to use and avoids duplicate classifications.

METHODS

Retrospective study of 460 women admitted for endometriosis.

RESULTS

One hundred and eighty-seven of 460 patients (41 %) had histologically confirmed DIE based on the revised Enzian classification. Further classification of these 187 patients using Enzian revealed 270 retroperitoneal lesions, as some patients had several DIE-type lesions simultaneously: 66 in compartment A (rectovaginal septum, vagina), 112 in compartment B (sacrouterine ligaments, pelvic wall), 58 in compartment C (bowel), 15 with adenomyosis uteri, 7 with bladder involvement, 8 with intrinsic involvement of the ureter, and 4 with bowel involvement. All 270 lesions were classified using Enzian alone and not with the rASRM score. There were no duplicate classifications (rASRM and Enzian).

CONCLUSIONS

The revised Enzian classification is an excellent complement to the rASRM score for morphological description of DIE.

Chronic Pain Syndromes in Gynaecological Practice: Endometriosis and Fibromyalgia

As gynaecologists frequently function as "general practitioners" for women, gynaecologists are frequently confronted with questions which initially appear to have only a tenuous connection to their field. Chronic pain syndromes represent a particular challenge, especially as pain syndromes are often associated with severe psychosocial stress for the affected woman. This article discusses some of the psychometric aspects of chronic pain in endometriosis and fibromyalgia together with practical therapeutic approaches.

Visual pain mapping in endometriosis

PURPOSE

To construct pain maps in order to describe the distribution of pelvic pain in a group of endometriosis patients and endometriosis-free patients, to assess the feasibility of this method.

METHODS

A total of 159 patients with pelvic pain who were scheduled for diagnostic laparoscopy.

RESULTS

A total of 117 patients with and 42 patients without endometriosis were included. The pain distribution between these two patient groups appeared to differ in some peripheral anatomical structures. In the endometriosis patients, the pain was most frequently located in the rectouterine pouch.

CONCLUSIONS

In endometriosis patients, pain mapping to assess preoperative pain sensations relative to the anatomic location of endometriotic lesions is feasible. The pain provoked by vaginal examination is frequently perceived as median relative to the actual anatomic location of the endometriotic lesions. Several anatomic and neurophysiological factors may explain this phenomenon.