Possible Mechanism of the Anti-Fertility Effect of Copper

Zipper et al.(1969) reported that a small copper (or zinc) loop placed in the lower portion of one of the uterine horns in rabbits produced a decrease in the number of implantation sites without producing a significant alteration in the control uterus. Silver, tin and magnesium were not effective. Zipper and co-workers (1970) utilized this observation to design a copper-containing intrauterine device for the prevention of fertility in the human female and reported that clinical effectiveness was related to the amount of copper present (Table 1).