Low testosterone can be a cause of infertility in men. It can cause low sperm counts, low motility, and probably even poor morphology. It also causes lots of other problems like poor muscle tone, weight gain, fatigue, and brittle bones to name just a few.
If a man has low testosterone, there are treatments available. It's important to treat not only because of the fertility aspects but general health also.
A very respected doctor in the field of men's reproductive health once explained it to me like this: you can replace the testosterone or kick start the testicles into making it on their own. If you just replace the testosterone, it will act as a male birth control. Sperm counts will decline until they are zero. It may or may not become permanent, it depends. It works, but if the man wishes to preserve his fertility then it is best to get his own testicles to produce testosterone as they would naturally. One way to do this is by one Clomid every other day. Doseage varies and will probably require a few blood tests to get it right.
Yes, it's a drug designed for women but it has this effect on men. It will take a few months for the sperm count to come back up (depending) as it takes several months for sperm creation.
A product called Conception XR is also very good at helping the body get sperm counts up naturally. It's a scientifically proven product designed by doctors. It's over the counter.
