"Normal" fertility could be defined as conception occurring within a 12 – 15 month period of regular unprotected sex.
Fertility is a highly complex process and infertility can be attributed to either male or female factors, or both. A male must produce semen that contains sufficient numbers of healthy motile sperm, and have the ability to achieve erection and ejaculate semen into the vagina.
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 which time 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
- Anti-sperm antibodies test - should be negative
In this guide