Influence of the menstrual cycle on flight simulator performance after alcohol ingestion

Objective: Previous studies investigating the influence of the menstrual cy cle on cognitive functioning of women after alcohol ingestion have obtained inconsistent results. The present study tested the hypothesis that flight simulator performance during acute alcohol intoxication and 8 hours after d rinking differs between the menstrual and the luteal phase of the menstrual cycle. Method: white female pilots (N = 24) were tested during the menstru al and the luteal phases of their menstrual cycles. On each test day they p erformed a baseline simulator flight, consumed 0.67 g/kg ethanol, and perfo rmed an acute-intoxication and an 8-hour-carryover simulator flight. Result s. Subjects reached highly significant increases in estradiol (E-2) as well as progesterone (P) levels during the luteal test day. Yet, there were no significant differences in overall flight performance after alcohol ingesti on between the menstrual and luteal phases during acute intoxication or at 8-hour carryover. we found no correlations between E-2 or P levels and over all flight performance. However, there was a statistically significant Phas e x Order interaction: Pilots who started the experiment with their menstru al day were less susceptible to the effects of alcohol during the second te st day than were pilots who started with their luteal day. Conclusions. The tested menstrual cycle phases and varying E2 and P levels did not signific antly influence postdrink flight performance. Because the present study inc luded a comparatively large sample size and because it involved complex "re al world" tasks (piloting an aircraft), we believe that the present finding s are important. We hope that our failure to detect menstrual cycle effects will encourage researchers to include women in their investigations of alc ohol effects and human performance.