Why is excess fructose consumption bad for a male?

Fructose is one of the forms of carbohydrates,the body metabolises it to give intermediate products which can be further broken down by entering into glucose break down pathway.

However,in male frictose consumption is so detrimental that the  excess exogenous fructose inhibits the endogenous ones.
(Exogenous: source is from outside the body while endogenous are produced in the body from the seminal vesicles)

This inhibition result in immobility of the male sperms  which can result in low sperm count.