Pain is the main symptom of endometriosis, but the reasons, extent, severity, or location is different among different patients. While the amount of lesions is not the only indicator of pain, researchers have established the existence of numerous factors that contribute to it. These include the hormonal similarity between endometriosis tissue and uterus tissue, inflammation, and chemicals produced by the endometriosis areas that can cause adherence of the pelvic organs and creation of scar tissue, or hormones and chemicals that are released by endometriosis tissue and irritate nearby tissue.
In addition, nodules or bumps in the endometriosis areas that result in lesions on the surface of pelvic organs can also cause pain, as well as nerves in the endometriosis lesions, or patches of endometriosis pressing against nearby nerve cells. Endometriosis-related pain can be severe and interfere with the normal, quotidian activities of the patients. Numerous research projects are focused on understanding how endometriosis is related to pain since it can result in the development of more effective treatments for this specific type of pain.