Yes. Even infrequent use of cocaine can cause a temporary 50% decrease in sperm.
It is also known to decrease motility, or the 'quality' of sperm, ie. How easily it can swim towards the egg etc. And augments the penetrating quality of the sperm, so that they are less effective at fertilization.
It is also known to decrease motility, or the 'quality' of sperm, ie. How easily it can swim towards the egg etc. And augments the penetrating quality of the sperm, so that they are less effective at fertilization.