Estrogen along with progestogen is the most widely used form of contraceptive by women. Its use in any dose, form or route has been shown to increase serum copper and ceruloplasmin levels in humans and rats. However, its effect on plasma zinc levels is not established unequivocally. We demonstrated in female Long-Evans-Hooded rats that 4 weeks after implantation with 17 beta-estradiol their serum copper and ceruloplasmin and brain copper levels increased while hepatic copper levels decreased significantly. Kidney copper levels increased transitorily after 2 weeks but not after 4 weeks. Zinc levels were affected only in the liver of these animals. It may be concluded that estrogen therapy depletes hepatic stores of these elements with abnormal accumulation of copper in the brain. Health implications of these changes need further investigation.