Effects of ethanol at four phases of the menstrual cycle

RATIONALE: Ovarian hormones, such as estrogen (E) and progesterone (P), interact with neurotransmitters, such as dopamine and gamma-aminobutyric acid, which are thought to be important in mediating the effects of ethanol. Therefore, it is possible that circulating ovarian hormones influence the acute subjective, behavioral, and physiological effects of ethanol, thus indirectly influencing ethanol consumption. OBJECTIVES: To examine the relationship between hormone levels and consumption of ethanol, this study investigated whether the effects of ethanol and the consumption of ethanol vary as a function of menstrual cycle phase. METHODS: Sixteen healthy women with normal menstrual cycles ingested ethanol at four hormonally distinct phases of the menstrual cycle, namely early follicular, late follicular, mid-luteal, and late-luteal. During each session, they first sampled three small doses of ethanol (0.2 g/kg each) at half-hourly intervals. They completed subjective and behavioral tests before the first dose and after each subsequent dose. After consuming the third beverage, the women were allowed to choose up to three additional doses of ethanol (0.2 g/kg), one every 30 min. RESULTS: Ethanol produced subjective effects typical for this drug (such as stimulant-like effects and euphoria), and it impaired eye movements and psychomotor performance. However, the effects of ethanol did not vary according to menstrual cycle phase, and consumption of ethanol also did not vary across the menstrual cycle. CONCLUSIONS: These results suggest that circulating ovarian hormones, like E and P, have little effect on either the acute subjective and behavioral effects of ethanol, or on ethanol consumption.