Abstract
The decline in the rate of childbirth observed in older couples gives rise to the question of whether there is a relationship between age and fertility. This question has been studied much more extensively for females than for males, perhaps because of the apparent lack of an age limit for males to have children. Investigating the effects of increased age on male fertility components, such as spermatogenesis, testicular histology and male reproductive histology, may help us understand the inverse relationship between age and birth rate. In this review, we have evaluated the literature regarding the effects of aging on fertility in an effort to determine how male reproductive capacity is affected by old age.