Headache after spinal anesthesia is a common complication, which is caused after dural puncture due to discharge of cerebrospinal fluid and reduction in the volume and pressure. Studies have shown that a variety of factors are involved including needle shape, needle size, patient's sex, age, duration of surgery, history of spinal anesthesia, and history of headaches. One possible factor is the phase of the menstrual cycle. Many studies have investigated the effect of the menstrual cycle on factors such as postoperative nausea, vomiting, propofol injection pain, and sore throat after intubation. Also, many studies have investigated the effect of different phases of the menstrual cycle on migraine headaches. Therefore, we decided to investigate the effect of different phases of the menstrual cycle on headache after spinal anesthesia. To determine the relationship between headache after spinal anesthesia and menstrual cycle, the study included all the patients undergoing spinal anesthesia in Shohada Ashayer and Asalian Hospitals of Khorramabad. This cohort study included 279 patients, and data collection tool was a questionnaire. The data from the questionnaire included age, menstrual phase, surgical procedures, pain location, pain intensity, history of spinal anesthesia, history of headache, and headache after spinal anesthesia. There was no statistically significant difference between the location of headache, the history of spinal anesthesia, the location of headache, the history of headache, and menstrual phase. Considering the high incidence of postdural puncture headache in follicular phase, it is recommended that patients with a high risk of headaches undergo spinal anesthesia and surgery in the luteal phase.