Lack of effect of alcohol on ethinylestradiol in premenopausal women

An acute elevation in estradiol during alcohol intake has been reported in postmenopausal women on estrogen replacement therapy. The objective of the present study was to investigate the acute and long-term effect of alcohol on ethinylestradiol, the estrogen component found in most oral contraceptiv es. Nine healthy premenopausal women with regular use of an oral contracept ive containing 30 mug ethinylestradiol and 75 mug gestodene were challenged with alcohol (0.4 g/kg p.o., approximately 2-3 standard drinks) 2 h after intake of the oral contraceptive pill at menstrual cycle day 14. Blood samp les were taken at 0, 2, 3, 4, 5, and 6 h from intake of alcohol. The challe nge was repeated after a 7-day period of controlled alcohol intake (0.8 g/k g/day) at cycle day 21. The same experiments were carried out during placeb o conditions. At day 21 an increase in the alcohol elimination rate was obs erved compared with day 14. No significant acute or long-term effect of alc ohol on ethinylestradiol was found. The lack of an acute effect comparable to that reported for estradiol may be due to the protection of the ethinyl group at the 17-position of ethinylestradiol. (C) 2001 Elsevier Science Inc . All rights reserved.