Aim: Estradiol and progesterone, the main hormones of the menstrual cycle, have modulating effects on neural mechanisms of anxiety and fear regulation. Anxiety is a common problem in patients undergoing interventional medical procedures. Therefore, interventional procedures are mostly performed under sedation. Studies are reporting that the level of anxiety in daily life varies in women depending on the phases of the menstrual cycle. In this study, we aimed to determine the effect of the menstrual cycle on the level of anxiety related to the interventional procedure in patients to be sedated. Methods: ASA I-II female patients between the ages of 18-40, with regular menstrual cycles (one cycle every 23-35 days), planned to undergo interventional procedures under sedation, were included in the study. Patients were asked about their last menstrual period, and those on the 1-10th day of the menstrual cycle were grouped as the follicular phase, and those on the 18-24th day were grouped as the luteal phase. Anxiety levels were assessed with the State-Trait Anxiety Inventory (STAI-X1) and compared between follicular and luteal phase patients. Results: The study was completed with 86 patients. Fifty-eight patients were in the follicular phase and 28 were in the luteal phase. The mean cycle frequency of women was 27.93 ± 3.30 days in the follicular phase and 27.29 ± 3.15 days in the luteal phase with no significant difference between the two groups (p= 0.39). While the STAI-X1 score of those in the follicular phase was 44.81, the score of those in the luteal phase was 40.71 and no significant difference was found between the two groups (p= 0.11). Anesthetic drug doses used in sedoanalgesia were similar between the two groups (p= 0.96). Conclusion: Patients in the follicular and luteal phases of the menstrual cycle have similar levels of pre-procedural anxiety.