Common causes of Male Infertility
Defective spermatogenesis: When the formation of sperms is affected. For the formation of a normal amount of sperm, the optimum temperature of the scrotum should be 1-2 degrees lower than the normal body temperature. This aids in a healthy hormonal balance.
Congenital: Birth defects such as undescended testes that can cause depressed spermatogenesis.
Autosomal (chromosomal) diseases like Kartagener Syndrome where there is a loss of mobility or ciliary function and sperm motility.
Hypospadias: A congenital defect where the opening of the penis is on the not on the tip but the underside, which causes failure to deposit sperm high up in the vagina.
Heat factor: When there is a rise in the temperature of the scrotum, such as in varicocele, it can interfere with the spermatogenesis.
Infections: The quality of sperms is affected by chronic bacterial infections adversely.
Other factors include general debilitating diseases, smoking, excessive alcohol and substance abuse, malnutrition, obesity, endocrine factors, immunological factors, physical obstruction in the efferent ducts and iatrogenic factors like radiation and antidepressant drugs.