Mood effects of alcohol and expectancies across the menstrual cycle

To examine menstrual cycle phase variations in alcohol absorption and mood before and after drinking alcohol, 96 volunteers female heavy drinkers, unaware they were in a menstrual cycle study, were randomly assigned to 12 equal-sized groups with controls for the effects of alcohol, expectancy, and menstrual cycle phase. Alcohol subjects received sufficient alcohol to raise their blood alcohol level to .07 mg %. Mood, assessed with the Profile of Mood States, did not differ across menstrual cycle phases at baseline, failing to support the notion of menstrual phase-related moods. The only mood changes were a Beverage by Trials interaction on the Vigor and Confusion scales and a main effect for trials on the Tension-Anxiety and Vigor scales. Peak intoxication level did not differ across phases. The present findings of an absence of menstrual cycle phase-related differences in mood or alcohol absorption support social learning theory and suggest that phasic variations in mood are socially learned. They also suggest the need for systematic study of methodologic factors in this research area.