In the first study, researchers found that a common cause of male infertility, varicoceles or varicose veins in the scrotum, also results in a depletion of testosterone.
In the second research, they noted that a common simple surgery can be used to treat varicoceles, thereby restoring fertility and improving testosterone levels.
Dr. Marc Goldstein, Professor of Urology and Reproductive Medicine at Weill Cornell Medical College and attending urologist at NewYork-Presbyterian/Weill Cornell, presented the results of both studies at the 2007 annual meeting of the American Society for Reproductive Medicine (ASRM) in Washington D.C.
He revealed that the presence of varicoceles causes significantly lower testosterone levels.
He also observed that following varicocele removal; testosterone levels are greatly improved - up to 100 percent - in more than two-thirds of the men studied.
With impaired testosterone production, males may experience andropause, analogous to menopause (lowered estrogen levels) in women.
A man may have a lowered sex drive, the inability to have erections, lowered muscle strength and energy level, and even depression. Also, affected men are more prone to osteopenia and osteoporosis, causing weakened bones.
Testosterone production is lowered when varicoceles become enlarged and twist around the testis of men. The condition can be hereditary and is found in 15 percent of all males; it also leads to a lowered sperm count and quality.
35 percent of all cases of primary infertility (first pregnancy attempt) and 80-percent of secondary infertility (attempts at pregnancy following a successful impregnation) are due to varicoceles.
"People often forget or often don't realize that the testes have two purposes," Dr. Goldstein said.
"One is the production of the sex cells (sperm), and the other is to produce testosterone," he added.
Dr. Goldstein helped to invent the microsurgery procedure now considered the standard in the treatment and removal of varicoceles.
Varicoceles begin forming at puberty and most doctors do not screen patients during routine check-ups.