Purpose: The aim of the study was to evaluate the severity of systemic responses to trauma; and thus, to determine the most advantageous timing for surgery among different phases of the menstrual cycle. Materials and Methods: 99 women were included in this study. They were patients who were in the postmenopausal period and patients in the different menstrual cycle phases of the premenopausal period. C-reactive protein, interleukin-1 beta, interleukin-6 and tumor necrosis factor-alpha levels were measured before and after surgery. Results: Among the menstrual cycle phases, the highest increases in the concentrations of IL-6 and TNF-alpha during the postoperative period were found in follicular phase patients. Luteal phase patients showed the lowest increases in interleukin-1 beta and interleukin-6 levels. TNF-alpha and CRP levels were increased significantly in all phases but not in the luteal phase. Conclusion: Timing of surgery in premenopausal patients seems effective on systemic inflammatory responses to trauma. Performing the operation based on the timing of the menstrual cycle will minimize the risk of operative trauma among premenopausal patients. This may be beneficial for their well-being.