Male infertility can be caused by environmental factors such as certain chemicals, some occupations and routinely sitting for long periods in a hot bath or hot tub.

Male infertility can also be a consequence of a varicocele, which is a collection of varicose veins in the scrotum. A varicocele can interfere with blood flow and thus inhibit heating and cooling of the testicles. A urologist usually treats a varicocele surgically.

Male infertility can also result when antisperm antibodies are present. Antibodies "mistake" sperm as foreign pathogens and seek to destroy them. Rarely, a man may produce antibodies to his own sperm usually as a result of testicular trauma or surgery such as vasectomy. The antisperm antibody process is similar to the body's response when challenged by virus or bacteria. The body makes antibodies to destroy the specific invading pathogens, and in cases of male antisperm antibodies, sperm.