The present paper analyzes the relation between alcohol intake and ser
um total estradiol in premenopausal women while attempting to control
or reduce several sources of variability of serum estradiol, Sixty pre
menopausal women were recruited, and alcohol intake was estimated by a
semiquantitative questionnaire, Interviews, anthropometric measuremen
ts, and blood drawings (after overnight fasting) were conducted twice,
1 year apart, Both blood samples were obtained on the same day of the
luteal phase of the cycle, in the same month and in the same hour and
minute of the day, Samples from the first drawing were stored at -80
degrees C. Serum from both drawings was assayed simultaneously and in
blind fashion, A significant association between alcohol intake and es
tradiol was found when estradiol was averaged across the two visits (S
pearman's r = 0.29; P < 0.05), To control for intraindividual variabil
ity of estradiol over time, participants were then divided into tertil
es of hormone distribution for each of the two sets of measurements an
d classified based on their consistency in estradiol across the two vi
sits, Women showing consistently high estradiol levels at both visits
were characterized by a significantly higher alcohol intake (92.8 g/we
ek) in comparison with those showing consistently low estradiol at bot
h visits (31.6 g/week). Furthermore, the prevalence of drinkers in the
group with consistently high estradiol was significantly higher than
in the group with consistently low estradiol, The present report indic
ates that drinkers seem to be characterized by consistently higher est
radiol than nondrinkers, and that when the variability of estradiol in
premenopause is considered, it is possible to identify a relationship
between alcohol intake and estradiol.