The aim of this study was to evaluate Ca 125 II, C-reactive protein (CRP) and serum amyloid A (SAA) and anticardiolipin antibody (aCL) concentrations for the diagnosis of pelvic endometriosis. The study population consisted of 15 women without endometriosis, as confirmed by laparoscopy (group A), and 35 patients with pelvic endometriosis. All of them were diagnosed by laparoscopy or laparotomy. Group B patients were divided into those at stages I and II of the disease (B I/II) and those at stages III and IV (B III/IV). Blood samples were obtained twice during the menstrual cycle: on day 1-3 of the cycle and on day 8-10 of the cycle. Our results claim that the measurement of these molecules may therefore provide a valuable tool in the diagnosis and management of endometriosis.