THE MENSTRUAL-CYCLE AND NAUSEA OR VOMITING AFTER WISDOM TEETH EXTRACTION

We have investigated 195 pre-menopausal women undergoing third molar e xtractions, in a prospective study, to assess the influence of the day of the menstrual cycle on the incidence of postoperative nausea or vo miting. In the 95 patients taking the oral contraceptive pill the inci dence of postoperative nausea or vomiting was higher on days 9 to 15 o f the menstrual cycle (P < 0.05) than on days one to eight and days 16 to the end of cycle. In the 100 patients who were not taking the oral contraceptive pill the incidence of postoperative nausea or vomiting was not higher on days 9 to 15. The strongest predictor for postoperat ive nausea or vomiting in our study was a previous episode of postoper ative nausea or vomiting (P < 0.005). Patients with a tendency to moti on sickness did not have a higher incidence of postoperative nausea or vomiting.