- An increase in the testes’ temperature, certain disorders, injuries, and some drugs and toxins can cause problems with sperm.
- Semen is analyzed, and sometimes genetic tests are done.
- Clomiphene, a fertility drug, may increase the number of sperm, but assisted reproductive techniques may be needed.
(See also Overview of Infertility.)
To be fertile, a man must be able to deliver an adequate quantity of normal sperm to a woman’s vagina, and sperm must be able to fertilize the egg. Conditions that interfere with this process can make a man less fertile.
Causes of Sperm Problems
Conditions that increase the temperature of the testes (where sperm are produced) can greatly reduce the number of sperm and the vigor of sperm movement and can increase the number of abnormal sperm. Some disorders of the testes, such as undescended testes and varicose veins (called a varicocele), increase the temperature of these organs. Effects of excessive or prolonged heat can last up to 3 months.TABLE What Causes Infertility in Men?
Certain hormonal or genetic disorders may interfere with sperm production, as can other disorders.
Exposure to industrial or environmental toxins and use of certain drugs can reduce sperm production. Taking anabolic steroids, such as testosterone and other synthetic male hormones (androgens), lowers production of the pituitary gland hormones that stimulate sperm production and can thus decrease sperm production. They can also cause the testes to shrink.
Erectile dysfunction (the inability to attain or maintain an erection sufficient for sexual intercourse) can cause infertility in men. It may result from a disorder, such as a blood vessel disorder, diabetes, multiple sclerosis, brain or nerve disorders (including Alzheimer disease, Parkinson disease, stroke, certain seizure disorders, and nerve damage due to prostate surgery), use of certain drugs (including some antidepressants and beta-blockers), use of recreational drugs (including cocaine, heroin, and amphetamines), or psychologic problems (including performance anxiety or depression). Erectile dysfunction may be the first clue that a man has a blood vessel disorder such as atherosclerosis.
