The concentration of copper in human uterine secretion during four years after insertion of a copper-containing intrauterine device.

The contraceptive action of a copper-containing intrauterine device (Cu IUD) is mainly associated with the copper ions released, thus its efficiency varies with the surface area of the copper wire. It is of considerable clinical interest to know the usful life-span of a Cu IUD. Therefore, the concentration of copper in the uterine secretion of women wearing a Cu-7 IUD (Gravigard) with a surface area of the copper wire of 200 sq mm was determined by atomic absorption spectroscopy. No decrease in the concentrations of copper was found in a series of women followed for 4 years after the insertion of a Cu IUD.