Release of copper ions from an intra-vas cooper-wire contraceptive device.

Insertion of a copper wire into the vas deferens of male rats released 4 micrograms of copper in themid portion of the vas deferens in two days time. In urethral and epidymal segments of the vas deferens copper released was less than one microgram. The present study demonstrates that the in vivo effects of 4 microgram of copper in 2 days time in the vas deferens are enough to induce antifertility in rats.