Is male fertility declining?

Numerous articles have suggested that sperm counts are falling and that male fertility is in decline. One of the most widely reported was a 1992 paper by Carlson and collaborators1 that looked back at 61 research papers published since 1938, and concluded that the average sperm count had dropped by 42 per cent. However, their analysis was flawed in many ways and their conclusions cannot be considered reliable.

Several more retrospective studies of semen quality have been published since, with conflicting results. Some suggest that sperm counts are declining, others that there is no change. Even if sperm counts are falling, the effect on fertility is also unclear. At present, there is no clear evidence one way or the other.

Could environmental factors be affecting male fertility today?

Many more environmental factors that can affect male fertility exist today than 50 years ago. The factors include:

* endocrine disrupters
* toxic pollutants
* sexually transmitted infections
* zinc deficiency
* alcoholism
* smoking
* anabolic steroid use
* ionising radiation.

Endocrine disrupters are chemicals present in the environment that, by virtue of their ability to adversely affect the endocrine (hormonal) system, cause health consequences. Several industrial pollutants can affect fertility, as can smoking and alcohol use. Some of these toxins can cause reproductive disorders, neurological disease, immune system disorders and cancer.

Pollutants that may cause fertility problems
Potential toxin - Source
• Thalates - Plastics industry
• Alkylphenols - Industrial and domestic detergents
• Bisphenol A - Lacquers to coat foods Dental treatments
• Organochlorine pesticides (Lindane, DDT, etc) - Lindane used on cereals, soft fruits, cabbage
• Dioxins - Paper production Transformer disposal
• Vinclozolin - Fungicide used on foods
• Phytoestrogens - Soya products

Full article: http://www.netdoctor.co.uk/menshealth/facts/semenandsperm.htm

Category: Male Fertility, sperm