Male Infertility
The male genital tract includes the testes, the epididymis, the vas, the prostate and urethra. The testes situated in the scrotum are mainly made up of loops of fine tubes (seminiferous tubules) which produce the sperm. The sperm cells mature as they pass through the epidiymis (a narrow system of tubes on the surface of the testes). The vas is a hollow tube, which carries the sperm from the epididymis to the urethra.
It takes 3 – 4 months for sperm to develop, during this time sperm production may be affected by febrile illness, exposure to drugs, toxins, radiation, local trauma or infection.
The primary laboratory test for male fertility is ” semen analysis”. The sample is obtained by masturbation or collected from a special condom following intercourse. Sterile containers must be used to collect the sample following three days of sexual abstinence.
A normal assessment should show :
- » Semen volume – 2-4mls
- » Sperm count – more than 20 million per ml
- » Sperm motility – more than 50% moving
- » Sperm morphology – more than 30% of normal shape
- » White blood cells – should be less than 1 million per ml
- » Antisperm antibodies test – should be negative
Common Male Infertility Problems :
Abnormal Sperm parameters :
- » Low sperm count – (oligospermia)
- » Poor sperm motility – (asthenospermia)
- » High abnormal forms – ( teratospermia)
Immunological factors :
Antisperm antibodies may occur following surgery, trauma or infections of the genital tract. Antisperm antibodies impair sperm motility and their ability to penetrate and fertilise an egg.
Absence of Sperm : (Azoospermia)
May be due to an obstruction at the level of the vas, epididymis, or even the testes, caused by previous infections, trauma or surgery. It may also be due to a bilateral congenital absence of the vas. Azoospermia could also be due to testicular failure caused by hormonal, chromosomal abnormalities, previous infection such as mumps or undescended testes.
A single sperm consists of a head, which contains the man’s genetic information and its tip, an 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.