“…A variety of causes of PONV have been described, including age, (10,14) female gender, (3,4,10,(14)(15)(16) type of surgery, (10,14,15) length of surgical procedure, (4,14,17) perioperative use of opioids, (7,10,(18)(19)(20)(21) anxiety, (14) history of motion sickness, (14,22) prior history of PONV, (14) anesthetic agent, (23,24) nonsmoker, (25) obesity, (14) and gastroparesis. (14) Although female patients are more likely to have PONV, there is not necessarily a relationship with the phase of menses, (26) although there is a report of increased PONV in the periovulatory and premenstrual periods.…”