Inflammatory and Oxidative Stress Biomarkers in Women with Endometriosis: Association with Disease Severity

Abstract

Background: Endometriosis is a chronic inflammatory disorder in which oxidative imbalance may support lesion survival and disease progression. Affordable circulating biomarkers may help assess severity in resource-limited settings.

Objective: To compare inflammatory and oxidative stress biomarkers in women with and without endometriosis and determine their association with disease severity.

Methods: This multicenter analytical cross-sectional study included 240 women undergoing pelvic laparoscopy at three tertiary-care hospitals in Pakistan. Histologically confirmed cases were categorized as revised American Society for Reproductive Medicine stage I–II or stage III–IV. Women without endometriosis served as controls. Serum high-sensitivity C-reactive protein, interleukin-6, tumor necrosis factor-alpha, malondialdehyde, superoxide dismutase and total antioxidant capacity were measured.

Results: The study included 160 women with endometriosis and 80 controls. Women with endometriosis had significantly higher inflammatory markers and malondialdehyde, whereas superoxide dismutase and total antioxidant capacity were significantly lower than controls (all p<0.001). Biomarker disturbance increased progressively from controls to stage I–II and stage III–IV disease. Interleukin-6, malondialdehyde and total antioxidant capacity remained independently associated with advanced disease. The combined biomarker model effectively distinguished stage III–IV disease, achieving an area under the receiver operating characteristic curve of 0.86.

Conclusion: Endometriosis was associated with increased systemic inflammation, lipid peroxidation and impaired antioxidant defense. A combined biomarker panel may support severity assessment but cannot replace clinical evaluation, imaging or histopathology.