Are higher male libidos and higher sperm count linked?

The first answer was correct in that testosterone is responsible for a mans libido and is likewise responsible for a woman's libido. The chemo probably stopped his production of testosterone temporarily and when it came back he became more horny than he was previously. It will do that to a man if he takes injections of testosterone like I do. lol Sperm has very little if not nothing to do with libido but libido will increase sperm production. Just looking a an erotic, sexy or nude woman's body can raise a mans testosterone and it takes testosterone to make sperm.