Review on copper in male reproduction and contraception.

The effect of copper on spermatozoa was studied as early as 1956 by Quatrefages, and has given rise to numerous studies and the assay findings have recurred in all the tissues of the male reproductive system, with considerable individual differences, the cause of which is not understood. Its role in the sperm is unclear, but it appears to be involved in spermatozoan mobility and it may also act at the pituitary receptors which control the release of LH. In the seminal fluid, the level of copper appears to fall in cases of azoospermia and to increase in oligo- and asthenozoospermia, but the findings of different authors are somewhat contradictory and some authors do not report any correlation between the seminal level of copper and the number of mobility of the gametes. It is true that the concentrations in the ejaculate vary considerably from one day to the next and that they also vary in different fractions from a single ejaculate. The toxic effects of copper on spermatozoa, which was demonstrated in 1850 by Quatrefages, has often been confirmed. Copper reduces the oxidative processes and glucose consumption, which reduces or abolishes mobility: this property is exploited in intrauterine devices. The use of copper for male contraception has given rise to experimental implantations at various sites within the male system: lumen of the deferens, epididymis, seminal vesicle scrotum and the mobility of the spermatozoa was abolished in all cases. Tissue toxicity makes it impossible to use this method in human practice.(ABSTRACT TRUNCATED AT 250 WORDS)