Endometriosis-associated infertility: aspects of pathophysiological mechanisms and treatment options

Cervico-vaginal secretion cytokine profile: A non-invasive approach to study the endometrial receptivity in IVF cycles

PROBLEM

Cytokines have a significant role in the process of embryo implantation, trophoblast growth, and differentiation by modulating the immune and endocrine system. The aim of this study was to investigate the profile of a large set of cytokines in the cervico-vaginal washing of women undergoing IVF, to explore the association of these proteins with a good receptive endometrium.

METHOD OF STUDY

A cohort of 155 women scheduled for IVF cycle was recruited. All patients were asymptomatic for genitourinary infections and had been screened for chlamydia, mycoplasma, and other bacterial infections. All IVF subjects were treated according to standard clinical and laboratory protocols. A panel of 48 immune factors was analyzed on cervico-vaginal washing, using magnetic bead-based multiplex immunoassays (Bio-Plex, BIO-RAD Laboratories, Milano, Italy).

RESULTS

A total of 99 patients reached embryo transfer, of which 31 had a clinical pregnancy. A pattern of four pro-inflammatory immune molecules, IL-12p40, IFN-a, MIF, and MCP3 (P < 0.001), was found significantly up-regulated in the cervico-vaginal fluid of women with clinical pregnancy. A significantly increased expression of IL-9, Gro_α , and SDF-1_α (P < 0.05) was observed in the presence of endometriosis, while high levels of IL-13 and L-15 were associated with ovulatory infertility factor (P < 0.05).

CONCLUSION

In this pilot study, we demonstrated that the expression of specific cytokines in the cervico-vaginal washing on the day of oocyte retrieval might have a positive correlation with the potential clinical pregnancy. Therefore, cervico-vaginal secretion cytokine profiling might be a new, non-invasive approach to study the endometrial receptivity in IVF management.

The efficacy of non-assisted reproductive technology treatment might be limited in infertile patients with advanced endometriosis in their 30s

AIM

To determine the efficacious treatment for infertile couples, we assessed the impact of infertility factors including endometriosis on assisted reproductive technology (ART) and non-ART treatment, and the effect of age in infertility treatment outcomes was also investigated.

METHODS

The medical records of 1864 females, infertile patients from January 2000 to December 2015 at our hospital, were retrospectively reviewed under the approval of the Institutional Review Board. We extracted 10 representative factors and calculated the cumulative live birth rate (CLBR) in these patients. Multivariate analysis of ART and non-ART treatment was performed to assess the impact of infertility factors, and the age-related decline in cumulative live birth rate was calculated by creating eight age-stratified subgroups.

RESULTS

In total, 21.9% and 49.4% of the patients conceived after being treated with non-ART and ART, respectively. Multivariate analysis revealed that age > 35, advanced endometriosis defined by the revised American Society for Reproductive Medicine classification system stages III to IV, and the past history or current presence of uterine fibroid had significantly negative impact on the outcome of non-ART. Age stratification revealed that advanced endometriosis adversely affected the outcome of non-ART, especially for patients in their 30s. Assisted reproductive technology treatment for patients with advanced endometriosis was shown to be efficacious because the negative impact had been diminished.

CONCLUSION

Considering that non-ART treatment had limited role in patients with advanced endometriosis, prompt initiation of ART in these patients aged as young as 30 years can be recommended to achieve conception.

The Clinical Anatomy of Endometriosis: A Review

Endometriosis is a gynecological disorder identified by the presence of ectopic endometrial tissue outside the uterus. Largely, it affects reproductive-aged women and is a major cause of infertility. Clinical manifestations of endometriosis include dyspareunia, cyclic menstrual pain, chronic pelvic pain, and dyschezia, all of which can affect the patient's quality of life and health severely; therefore, it is paramount that medical treatment is initiated as soon as endometriosis is suspected clinically. In this review, we examine the known anatomic principles of endometriosis in the literature and outline ways to manage patients with this condition better.

Endometriosis

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

Endometriosis and infertility: Insights into the causal link and management strategies

When evaluating the correlation between endometriosis and infertility with application of the evidence-based guidelines to establish causality in medicine, it becomes apparent that endometriosis causes infertility. This is supported by a strong and consistent association between the two in various settings (prevalence, natural conception, intrauterine insemination (IUI), and assisted reproductive technologies (ARTs)), evidence for a temporal relation, arguments for a dose-response gradient, and proven effects of the removal of lesions on infertility. Next to surgical treatment of endometriosis lesions, medically assisted reproduction treatments such as IUI and ART such as in vitro fertilization are cornerstones of the management of endometriosis-related infertility. Because the revised American Society for Reproductive Medicine (rASRM) staging system is poorly correlated with pregnancy rates as opposed to the Endometriosis Fertility Index (EFI), the latter should be used as the preferred clinical tool to counsel patients on their postoperative fertility management options.

Novel CTCF mutations in Chinese patients with ovarian endometriosis

Endometriosis is a common gynecological disease characterized by the outgrowth of the endometrium, however, the detailed molecular etiology remains largely uncharacterized. Recent studies have implicated that endometriosis is potentially a precancerous lesion, and that CCCTC‑binding factor (CTCF) mutations may be involved in the pathogenesis of this disorder. However, the detailed CTCF mutation spectrum in Chinese patients with ovarian endometriosis remains largely unknown. In the present study, a cohort of 92 patients with ovarian endometriosis were analyzed for the presence of CTCF mutations by sequencing the entire coding regions. In addition, 67 healthy eutopic endometrial tissues and 46 healthy ovarian tissues from control samples (without endometriosis) were also analyzed. In total, two CTCF missense mutations, p.K206E (c.616A>G) and p.H373L (c.1118A>T), were identified in 2/92 (2.2%) endometriotic lesions. The patient with the p.K206E mutation was 26 years old and diagnosed with primary infertility, whereas the patient with the p.H373L mutation was 37 years old and concurrently diagnosed with uterine leiomyoma. The p.H373L mutation was previously identified in endometrial cancer samples with low frequency, while the p.K206E mutation was novel. In addition, no CTCF mutations were detected in the 67 healthy eutopic endometrial and 46 healthy ovarian tissue samples. In silico prediction and evolutionary conservation analysis suggested that these CTCF mutations may be pathogenic. In summary, the present study identified 2 potential pathogenic CTCF mutations in endometriotic lesions from 2/92 patients with ovarian endometriosis. These results, together with a prior exome‑sequencing based study, suggest that CTCF mutations may be involved in the development of ovarian endometriosis.

Effects of pelvic endometriosis and adenomyosis on ciliary beat frequency and muscular contractions in the human fallopian tube

BACKGROUND

Pelvic endometriosis (EM) and adenomyosis (AM) have different effects on the fallopian tube. This study aimed to assess the transport capability of the fallopian tube in women with pelvic EM or AM.

METHODS

Twenty women with uterine leiomyoma (control group), 20 with adenomyosis without pelvic EM (AM group) and 35 with pelvic EM without AM (EM group) were included. EM cases were further divided into the tubal EM and non-tubal EM subgroups. Ciliary beat frequency (CBF), percentage of ciliated cells, and smooth muscle contraction were measured.

RESULTS

CBFs of the ampulla in EM cases were significantly lower than those of control and AM cases; CBFs of the ampulla and isthmus in tubal EM cases were significantly lower than those of the control group and non-tubal EM subgroup. In both the ampulla and isthmus segment, percentages of ciliated cells in EM patients were significantly lower than those of AM and control patients; the tubal EM subgroup showed significantly lower values than the control group and non-tubal EM subgroup. Amplitude-to-weight ratios of longitudinal muscular contractility in EM cases were significantly lower than control values; tubal EM cases showed significantly lower values than controls and the non-tubal EM subgroup. Contraction frequencies in EM cases were significantly lower than those of control and AM cases, in both longitudinal and circular muscles; tubal EM cases showed significantly lower values than controls and the non-tubal EM subgroup.

CONCLUSION

EM with tubal EM damaged transport function of the fallopian tube, to varying degrees, whereas tubal function in EM without tubal EM and in AM is not altered.

The role of complement components C1q, MBL and C1 inhibitor in pathogenesis of endometriosis

Purpose

The purpose of the work was to evaluate possible associations between the complement components C1q, mannose-binding lectin (MBL) and C1 inhibitor (C1INH) with pathogenesis of endometriosis.

Methods

Concentrations of C1q, MBL and C1INH were measured by ELISA in peritoneal fluid (PF) in 80 women with or without endometriosis.

Results

Significantly higher PF levels of C1q, MBL and C1INH in women with endometriosis compared to control group were observed (p < 0.0001). A higher concentration of the studied parameter was found in PF of women at the early stage of the disease, as compared to women with advanced endometriosis (p < 0.0001).

Conclusions

Our research suggests that in the peritoneal cavity in women with endometriosis there are abnormal regulations of both the classical and lectin pathways of the complement system. This can suggest impairments in purification of peritoneal cavity from ectopic endometrial cells and augmented local inflammation in endometriosis patients.

From Endometriosis to Pregnancy: Which is the “Road-Map”?

In the last decade, pregnancy was considered as a therapeutic period for patients affected by endometriosis and painful symptoms. However, several studies have taken into consideration how endometriosis affects pregnancy achievement and pregnancy development, including obstetric complications. The adverse effects of endometriosis on the development of pregnancy include miscarriage, hypertensive disorders and pre-eclampsia, placenta previa, obstetric hemorrhages, preterm birth, small for gestational age, and adverse neonatal outcomes. The aim of this review is to analyze the current literature regarding the relationship between different forms of endometriosis (endometrioma, peritoneal endometriosis, deep endometriosis) and infertility, and the impact of endometriosis on pregnancy outcomes.