Effects of Gossypol on the fertility of male rats, hamsters and rabbits

Oral administration of Gossypol acetic acid induced sterility in male hamsters and rats when given at a dose level of 5 or 10 mg/kg daily for 12 weeks. This was shown by the appearance of dead and abnormal sperm in the male tract and the failure of pregnancy or decrease in implantation sites in the females mated to the Gossypol-treated males. Similar treatment of male rabbits at dose levels varying from 1.25 to 10 mg/kg and given for 5 to 14 weeks did not affect the average number of sperm per ejaculate, although the motility of sperm was poor during treatment in some bucks. The pregnancy rates and the proportion of implantation sites were also not affected by insemination of female rabbits with sperm from males during treatment with Gossypol.

A-nor steroids as post-coital contraceptives in the hamster with special reference to the transport and degeneration of eggs

Two A-nor steroids, Anordrin and H241, showed a marked antifertility effect when given orally to hamsters at 10 mg/kg/day for three or four days after mating. Further study indicated that the antifertility effect was due to a disturbance of egg transport, retarded development and degeneration of fertilized eggs.