The strongest evidence of cannabis induced alterations in male fertility is in the category of semen parameters. Research supports a role for cannabis in reducing sperm count and concentration, inducing abnormalities in sperm morphology, reducing sperm motility and viability, and inhibiting capacitation and fertilizing capacity. Animal models demonstrate a role for cannabis in testicular atrophy, and reduced libido and sexual function but to our knowledge these results have not yet been replicated in human studies.
"These results" clearly refers to the animal model studies they mention later, so that caveat does not apply to the "strongest evidence" they lead with, about sperm motility and viability, etc. At least not to judge by the abstract.
