The aim of this study was to evaluate differences in levels of serum and monocyte derived interleukin (IL)-1, IL-6 and neopterin (NPT) in women with normal or abnormal menstrual cycles and women with endometriosis. The women participating in this study were divided into 4 groups: 25 women with normal menstrual cycle; 25 women taking oral contraception (OC); 20 postmenopausal women and 25 endometriosis patients. IL-1beta, IL-6 and NPT levels in serum and monocyte culture media were measured with ELISA methods. The data collected showed the lowest serum NPT levels in women with follicular menstrual cycles. The levels of both types of interleukins in serum were the lowest in women using OC. In contrast, the highest concentrations of all cytokines were found in the serum of women with endometriosis. The lowest monocyte activity was observed in women with a follicular menstrual cycle phase and the highest in endometriosis. Monocytes from women using OC secreted similar amounts of cytokines to the cells during the follicular menstrual cycle phase. Changes occurring at the time of contraception, after menopause and during endometriosis, are followed by changed proinflammatory monocyte activity, which is associated with different secretion of cytokines. OC can inhibit inflammatory monocyte properties. Lower serum concentration of cytokines compared to cell secretion may suggest some control mechanisms of monocyte activity.