Several factors are responsible for infertility in males.
Formation of healthy sperm: You must produce healthy sperm. This involves the growth and formation of the male reproductive organs during puberty. At least one of your testicles must be functioning correctly, and your body must produce testosterone and other hormones to trigger and maintain sperm production.
Sperm carried into the semen: Sperm has to be taken into the semen. Once sperm is produced in the testicles, delicate tubes transport them until they mix with semen and are ejaculated out of the penis.
Sperm in the semen: There needs to be enough sperm in the semen. If the number of sperm in your semen is low, it decreases the odds that one of your sperm will fertilize your partner's egg. A low sperm count is fewer than 15 million sperm per milliliter of semen or fewer than 39 million per ejaculate.
