Problems with sperm

[Lizzy Liz]

Sperm may be too few in number, move too slowly, or be structurally abnormal, or their passage out of the body may be blocked or disrupted.

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.