Received November 27, 2025
Accepted December 05, 2025

Objective: The etiopathogenesis of endometriosis-related infertility is still under investigation, even regarding endometriomas. It is believed that oocyte quality plays an important role in impairing natural fertility of those patients, with systemic inflammation and oxidative stress being mediators of oocyte damage. Eicosanoids are bioactive lipids produced in response to inflammatory or oxidative conditions, which are involved in various ovarian processes, and whose alteration could impact oocyte competence. This study aimed to compare serum and follicular profiles of eicosanoids between women with and without endometriosis (with and without endometrioma). Methods: In this prospective cohort study, blood and follicular fluid samples from 18 infertile women with endometriosis (8 with and 10 without endometrioma) and 20 patients with tubal and/or male factor of infertility were collected on the day of oocyte retrieval. Samples had eicosanoid profile analyzed through liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: No differences were found when comparing serum eicosanoids between endometriosis and control groups. When subdividing the endometriosis group into those with and without endometrioma, we observed lower serum levels of 5-Hydroxyeicosatetraenoic acid (5-HETE) among those with endometrioma (38.47 pg/mL vs 120.45 pg/mL; p = 0.01). Increased follicular levels of Eicosapentaenoic acid (EPA) were found in women with endometriosis (4038.52 pg/mL; p=0.03) and in those with endometrioma (5811.50 pg/mL; p=0.005) compared to controls (1159.83 pg/mL). Conclusion: The findings suggest that pelvic disease promotes systemic pro-inflammatory alteration, while endometrioma induces local anti-inflammatory response, probably aiming to prevent oocyte damage, evidencing different mechanisms underlying endometriosis-related infertility depending on the type of lesions.