The Relationship between Uterine Endometrial Neovascularization and Pelvic Pain Intensity

BACKGROUND AND OBJECTIVE: Pelvic pain is one of the most important symptoms of endometriosis. There is evidence that high blood flow to endometrioma is associated with more pelvic pain, but this has not been completely proven. Therefore, the present study was conducted to evaluate the relationship between uterine endometrial neovascularization and pelvic pain intensity. METHODS: In this cross-sectional study, 76 patients with ovarian endometrioma (based on the final diagnostic pathology) were divided into two groups of mild/moderate pelvic pain (VAS lower than 66) and severe pelvic pain (VAS 66 to 100) in terms of pelvic pain intensity (using the visual analog scale). Patients underwent transvaginal doppler ultrasound prior to surgery, and endometrial neovascularization, as well as resistive index (RI) and pulsatility index (PI) in the artery of the endometrioma cyst wall were measured and were compared between two groups of mild/moderate pelvic pain and severe pelvic pain. FINDINGS: Moderate and severe neovascularization (50%) in patients with severe pelvic pain was significantly higher than patients with mild/moderate pelvic pain (13%) (p=0.005). The mean RI in the group with severe pelvic pain (0.59±0.05) was lower than the mild/moderate group (0.66±0.06) (p<0.001). The mean PI in patients with pelvic pain (1.07±0.13) was lower than patients with mild/moderate pelvic pain (1.14±0.15) (p=0.03). CONCLUSION: Severe neovascularization and low RI and PI indices in transvaginal doppler ultrasound of ovarian endometrioma indicate high activity of endometrium and is associated with severe pelvic pain in patients.