Hormonal imbalance: Infertility happens when a couple cannot conceive after having regular unprotected sex.It may be that one partner cannot contribute to conception, or that a woman is unable to carry a pregnancy to full term. It is often defined as not conceiving after 12 months of regular sexual intercourse without the use of birth control.
The following are common causes of infertility in men.
Low sperm count: The man ejaculates a low number of sperm. A sperm count of under 15 million is considered low. Around one third of couples have difficulty conceiving due to a low sperm count.
Low sperm mobility (motility): The sperm cannot "swim" as well as they should to reach the egg.
Abnormal sperm: The sperm may have an unusual shape, making it harder to move and fertilize an egg.
If the sperm do not have the right shape, or they cannot travel rapidly and accurately towards the egg, conception may be difficult. Up to 2 percent of men are thought to have suboptimal sperm.
Abnormal semen may not be able to carry the sperm effectively.
This can result from:
A medical condition: This could be a testicular infection, cancer, or surgery.
Overheated testicles: Causes include an undescended testicle, a varicocele, or varicose vein in the scrotum, the use of saunas or hot tubs, wearing tight clothes, and working in hot environments.
Ejaculation disorders: If the ejaculatory ducts are blocked, semen may be ejaculated into the bladder
Hypogonadism, for example, can lead to a testosterone deficiency.