Copper wire was inserted into the vas deferens and its effect of the reproductive system and fertility performance of rats was investigated. The copper wire was 100% effective as a contraceptive for up to 4 months if placed correctly, and resulted in decapitation of most of the spermatozoa. No differences between the rats with an intravasal copper wire and the sham-operated controls were found for the weights of the gonads and accessory sex glands or for protein, RNA, DNA and fructose concentrations. The intravasal copper device appears to be promising for the development of a long-term method for male contraception.

No abstract

Summary. A 1\m=.\5cm long copper wire caused complete inhibition of fertility in male rats when placed properly in the vasal lumen. The contraceptive effectiveness of the device was directly proportional to the surface area of the device and was non-obstructive. The release rate of copper in vivo from a 1 \ m=. \ 5cm long wire was 11\m=.\6 \g=m\g/dayduring the first month and 6\m=.\8\g=m\g/dayover the first 3 months. The contraceptive action of the wire starts about 20 days after insertion. Fertility was regained in 67% of the rats by 90 days after removal of the device. Similar devices of stainless steel and silver did not affect fertility.