There are many reasons which can deplete the number of healthy motile sperms in a male’s semen. The factors which negatively affect the quality of semen can be classified into three categories.

These are pre-testicular, testicular, and post-testicular factors. Some commonly found causes of low sperm count are hypogonadism, varicocele, hydrocele, mumps, malaria, and trauma to testis are few testicular reasons for low sperm count.

Strenuous exercises, lifting heavy objects, recreational drugs, too much alcohol intake, exposure to heavy metals, radiation therapies, medicines that alter androgen levels, too much cycling, too much horse riding, and exposure to heat are few pre-testicular reasons for low sperm count.