A single sperm consists of a head, which contains the man's genetic information, and its tip (acrosome) which will help the sperm penetrate the outer shell of the egg; a midpiece, which supplies the energy needed for movement; and the tail which propels the sperm forward.
In order for sperm to be “normal”, the sperm count, motility and appearance must be within certain parameters. Male subfertility can occur due to oligospermia (low sperm count), asthenospermia (poor motility) or teratospermia (high incidence of abnormal forms).
Immunological factors can also affect male fertility. Anti-sperm antibodies may occur following surgery, trauma or infection of the genital tract. These antibodies impair sperm motility and affect the sperm’s ability to penetrate and fertilise and egg.
In some cases of male fertility problems, azoospermia (the absence of sperm) can occur. This may be due to an obstruction in the vas, epididymis, or even the testes, or to a bilateral congenital absence of the vas. Azoospermia could also be due to testicular failure caused by hormonal or chromosomal abnormalities, previous infection such as mumps or undescended testes.
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