To the editor: Ambulatory surgery has rapidly increased in recent years due to the request of patients and the increase in the cost of inpatient health services [1]. Patients who undergo ambulatory surgery usually receive general anesthesia or local anesthesia with sedation. Studies have reported that these types of anesthesia can impair cognitive and psychomotor performance [2-4]. The impairment of cognitive and psychomotor performance may threaten the safety of patients who undergo ambulatory surgery because patients are often discharged 2 to 3 hours post-operatively. Therefore, discharge criteria have been devised to ensure patient safety [2].Gynecologic surgeries such as loop electrosurgical excisional procedure (LEEP) are usually performed as ambulatory surgery. However, there is no study addressing the usefulness of discharge criteria in patients who undergo ambulatory gynecologic surgery.Recently, we adopted the modified Korttila discharge criteria (MKDC) [5] as an element of clinical pathway of LEEP in our institute. Approximately 2 to 3 hours after LEEP, a nurse evaluated the patient using the MKDC. If the patient passed all the MKDC, the patient was discharged without notification to physicians. If the patient did not pass all the MKDC, the nurse notified the results of the MKDC to physicians, who in turn made the discharge decision. Between 3 and 7 days after discharge, the head nurse of the gynecology ward called by telephone the patient and asked whether or not the patient revisited the hospital after discharge due to medical problems.Ninety-nine patients were evaluated using the MKDC and 96 patients passed all elements of the MKDC. One and two patients failed the 10th and 12th elements of the MKDC, respectively. The patient who failed the 10th element of the MKDC (discharge order) was not discharged because the frozen biopsy of the LEEP specimen reported an invasive cervical cancer. Two patients who failed the 12th element of the MKDC (accompanying escort) were discharged with precautions. None of 98 patients who were discharged on the day of surgery revisited the hospital due to medical problems. Sixteen of 17 nurses completed the evaluation using MKDC within 5 minutes and responded that use of the MKDC is necessary to ensure the safety of patients.We think that every institute and physician has their own discharge criteria for patients who undergo ambulatory gynecologic surgery. However, we believe that validated discharge criteria should be developed to ensure the safety of patients and to protect ourselves from potential lawsuits.