Background & Aims

Chronic pelvic pain (CPP) is noncyclical pain lasting for 6 months or more, localized in area of the anatomical pelvic, anterior abdominal wall, at or below the umbilicus. Endometriosis, as a chronic inflammatory gynecological disease that depends on estrogen levels, is considered to cause CPP. Many pain syndromes are characterized by increased sensitivity of the central nervous system (CNS) to the perception of pain signals. Nociceptive signals originate in the periphery, subsequently relaying to different levels of the nervous system. Any dysfunction of the pain pathway can lead to uncontrolled, persistent pain. During the study of CPP in endometriosis it is essential not to overlook myofascial tension, which occurs due to the repeated influx of peripheral nociceptive impulses into central brain regions, that lead to the development of hypertonus in associated body areas.
The aim of this systematic review is to study the pathogenesis of chronic pelvic pain in endometriosis.

Methods

The search for current articles on chronic pelvic pain in endometriosis was conducted covering the period from 2008 to 2023 in PubMed, Cochrane Library, Google Scholar and ClinicalTrials databases. The key words were: “endometriosis,” “pelvic pain,” “nociception,” “CNS changes” and “myofascial pain”. Both clinical and experimental studies were conducted in order to study the pathophysiology of chronic pelvic pain in endometriosis.

Results

According to V. Anaf and co-authors pain arises as a result of edema of affected by fibrotic tissue involvement areas, organ walls infiltration, scar tissue mechanical stimulation and formed adhesions at infiltrative endometriosis. Matteo Morotti and co-authors highlight that pain perception in patients with endometriosis occurs through direct activation of peripheral nociceptors due to the release of algogens and inflammatory molecules from ectopic endometrium into peritoneal fluid. Sensory fibers’ thickening and sympathetic pathways’ thinning lead to an imbalance between sensory and sympathetic innervation, that cause peripheral nociception as a result of close interrelated pain and inflammation mechanisms. In animal laboratory trials over rodents with endometriosis an increase of microglial somas in cortex and thalamus with no microglia and astrocyte volume changes are revealed. Hypersensitivity in the hind limbs and abdomen is also detected in mice with endometriosis.

Conclusions

The problem of chronic pelvic pain in endometriosis is currently considered to be relevant. Despite a big quantity of researches on CPP pathogenesis at endometriosis, a number of problems remain unsolved and require further study as well as experimental and clinical research.

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Presenting Author

Aleksandra Stamenkovich

Poster Authors

Aleksandra Stamenkovich

MB

Medical Faculty of the University of Belgrade

Lead Author

E-mail

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Abdominal and Pelvic Pain