ABSTRACT: OBJETIVE: Thrombospondin-1 serum levels is correlate with pelvic pain in patients with ovarian endometriosis. PATIENTS: Thrombospondin-1 serum levels were prospectively analysed in 51 patients (group A asymptomatic patients or patients presenting mild dysmenorrhea and women comprised group B severe dysmenorrhea and/or chronic pelvic pain and/or dyspareunia) who underwent surgery for cystic ovarian endometriosis to asses whether a correlation exists among thrombospondin-1 serum levels and pelvic pain. RESULTS: From 56 patients, five cases were ultimateley excluded, because the histological diagnosis was other than cystic ovarian endometriosis (2 teratomas and 3 haemorragic cysts). The mean thrombospondin-1 serum levels in group A was 256,69 pg/ml_+37,07 and in group B was 291,41 pg/ml + 35,59. CONCLUSION: Pain symptoms in ovarian endometriosis is not correlated with thrombospondin-1 serum levels.