Male age can affect sperm quality, but there is not as marked a decline in fertility as in the case of women. After the age of 40, male fertility decreases. It has been observed that with age there is a slow but progressive reduction in seminal volume, a decrease in sperm concentration and an increase in oxidative stress.
In addition, the likelihood of sperm having genetic alterations also increases. Nevertheless, a man can still be fertile in his 50s, 60s and even 70s.
In the following article there is more information on the effect of age on men: What is Andropause / male menopause