Endometriosis-associated infertility: From pathophysiology to tailored treatment

Abstract

Despite the clinically recognized association between endometriosis and infertility, the mechanisms implicated in endometriosis-associated infertility are not fully understood. Endometriosis is a multifactorial and systemic disease that has pleiotropic direct and indirect effects on reproduction. A complex interaction between endometriosis subtype, pain, inflammation, altered pelvic anatomy, adhesions, disrupted ovarian reserve/function, and compromised endometrial receptivity as well as systemic effects of the disease define endometriosis-associated infertility. The population of infertile women with endometriosis is heterogeneous, and diverse patients’ phenotypes can be observed in the clinical setting, thus making difficult to establish a precise diagnosis and a single mechanism of endometriosis related infertility. Moreover, clinical management of infertility associated with endometriosis can be challenging due to this heterogeneity. Innovative non-invasive diagnostic tools are on the horizon that may allow us to target the specific dysfunctional alteration in the reproduction process. Currently the treatment should be individualized according to the clinical situation and to the suspected level of impairment. Here we review the etiology of endometriosis related infertility as well as current treatment options, including the roles of surgery and assisted reproductive technologies.

A large-scale causal analysis of gut microbiota and endometriosis associated infertility: A Mendelian randomization study

“…We estimated the strength of the IVs using the F-statistic; where F < 10, weak instrumental variable bias was assumed. The F statistic (calculated as 2 , and indicating the proportion of variance in the exposure explained by the genetic variants; EAF = effect allele frequency; n = sample size; and k = number of IVs) indicates the strength of the relationship between the IVs and exposure. [31,32] After removing the aforementioned noncompliant instrumental variables, we repeated the MR analysis to obtain the final MR estimate.…”

Ovarian reserve markers of women with superficial endometriosis

“…The association of all endometriosis types and subfertility is well established 29 . Several mechanisms have been proposed to explain endometriosis associated subfertility, including distorted anatomy, chronic inflammation, cell signaling, epigenetic changes and lower ovarian reserve 30–32 …”

Endometriosis and subfertility

“…Endometriomas are found in 17–44% of women with endometriosis, and almost one‐third of those affected have bilateral cysts 11 . There is growing evidence that endometriomas have a detrimental effect on ovarian function, not only via a space‐occupying effect, but also from causing an oxadative stress reaction in healthy ovarian tissue, which may lead to fibrosis, loss of cortical stroma, smooth muscle cell metaplasia, impaired vascularisation, and, at later stage, reduced follicular maturation and atresia in early follicles 12 . Endometriomas can also be a significant cause of dyspareunia, which can lead to impairment of sexual function, relationships and psychological wellbeing 13,14 …”