Influence of the menstrual cycle on the incidence of nausea and vomiting after laparoscopic gynecological surgery: a pilot study.

Study Objective: To investigate whether the phase of menstrual cycle influences the incidence of postoperative nausea and vomiting (PONV) in women undergoing general anesthesia for elective laparoscopic gynecological surgery.

Design: Prospective, observational, blinded study.

Setting: General hospital, Postanesthesia Care Unit, and gynecologic floor room.

Patients: 111 ASA physical status 1 and 2 women, aged 18 to 53 years.

Interventions: Patients were classified into three groups according to the phase of menstrual cycle at the time of anesthesia: Group F1: follicular phase (menstrual days 1-8; n = 34); Group O2: ovulatory phase (days 9-15; n = 40); and Group L3: luteal phase (days 16 to end of cycle; n = 37). Anesthetic, postoperative pain management, and antiemetic regimens were standardized.

Measurements: Frequency of nausea, vomiting, or both were assessed for early (0-2 hrs). Late PONV (2-24 hrs) along with the use of rescue antiemetic, severity of nausea, and pain.

Main Results: In the follicular (n = 34), ovulatory (n = 40) and luteal phase (n = 37) groups, the frequencies of PONV over 24 hours were 35%, 38%, and 14% (P = 0.04), respectively. This was due to differences in the early postoperative period where the frequencies were 21%, 25%, and 3% (P = 0.02), respectively, as frequencies were similar in the late period (15%, 20% and 14%, P = 0.71), respectively. Nausea scores, rescue antiemetic usage, pain scores, and opioid consumption were similar in the groups.

Conclusion: Patients in the luteal phase of their menstrual cycle may have a decreased risk of PONV after laparoscopic gynecological surgery in the early postoperative period.