Effect of Menstrual Cycle on Rewarding Properties of Alcohol Cues in Women

Objective: Compared with men, women are disproportionately affected by alcohol, including greater risks of behavioral impairment and relapse from abstinence-based treatments. One potential mechanism underlying this disparity is ovarian hormone fluctuations across menstrual cycle phases, particularly estradiol (E2). Preclinical and clinical studies have shown that E2 levels positively correlate with alcohol consumption, suggesting E2 modulates drinking. Rewarding properties of alcohol are thought to mediate this relationship. The present study tested the degree to which women report increased rewarding effects from alcohol and heightened attention to alcohol-related cues when E2 was elevated during the late follicular phase of the menstrual cycle. Method: Fifty women aged 21-29 participated in a within-subjects placebo-controlled study examining how menstrual cycle phase alters the rewarding properties of alcohol and alcohol-associated cues when sober and intoxicated, as measured by their attentional bias toward alcohol-associated cues and subjective reports. Measures were obtained following 0.60 g/kg alcohol and placebo during the early follicular phase when E2 was low and the late follicular phase (i.e., ovulation) when E2 was elevated. Results: Attentional bias to alcohol-associated cues was greater during the late follicular phase in both sober and intoxicated states. Women reported rewarding effects from alcohol, but no effects of phase were observed. Conclusions: The findings suggest that the rewarding properties of alcohol-associated cues might be enhanced during the late follicular phase of the menstrual cycle when E2 is elevated, possibly increasing the risk for excessive drinking in women during this phase.