Preliminary evidence of increased alcohol use associated with ethinyl estradiol levels in women using oral contraceptives

Alcohol use is highly prevalent in young adult women and rates of alcohol use disorder are rising rapidly in this population. Further, emerging evidence suggests that circulating levels of ovarian hormones influence alcohol consumption, with increased consumption associated with higher estradiol and lower progesterone levels. However, less is known about the influence of synthetic hormones (contained in oral contraceptive (OC) pills) on alcohol use. The current study examined the influence of OC pill phase, ethinyl estradiol (EE) levels, and progestin levels on self-reported alcohol consumption in healthy female drinkers. Young adult female drinkers using OCs (N = 21) reported alcohol use across one OC pill pack using the Timeline Followback and provided blood samples during both pill phases to measure synthetic hormone levels. We compared alcohol use between OC pill phases (active vs. inactive) using linear mixed effects models for repeated measures and examined correlations between alcohol use and EE and progestin levels. Results showed that women with higher EE levels reported increased alcohol consumption (r = 0.56, p = 0.01) and binge drinking (r = 0.45, p = 0.04) in the active pill phase. Progestin levels and pill phase were not significantly associated with alcohol consumption. These findings provide preliminary data suggesting increased levels of EE from OC pills are associated with excessive alcohol consumption in women. Further research is needed to determine if EE plays a causal role in increased alcohol consumption. This line of research could inform female-specific AUD prevention and treatment strategies among the large subpopulation of women using hormonal contraceptives.