Of the 80% of cases with a diagnosed cause, about half are based at least partially on male problems (referred to as male factors). Infertility in men is usually caused by problems making sperm – producing too few sperm or none at all. There may also be problems with the sperm’s ability to reach the egg and fertilize it.
Sometimes genetically inherited problems can affect the sperm. Other times complications develop later in life as a result of illness or injury. A man’s lifestyle and overall health can dramatically affect the number and quality of his sperm.
Variables that can affect men’s sperm include:
- alcohol consumption
- drug use
- environmental toxins
- health problems
- certain medicines
- radiation treatment and chemotherapy
The causes of sperm production problems can exist from birth or develop later as a result of severe medical illnesses, including mumps and some sexually transmitted diseases, or from a severe testicle injury, tumor, or other problem. Inability to ejaculate normally can prevent conception, too, and can be caused by many factors, including diabetes, surgery of the prostate gland or urethra, blood pressure medication, or impotence.