19 Feb 2008: Damage to sperm passed onto children

Men whose sperm are damaged by drinking, smoking or other environmental toxins could be affecting their children, their children's children and beyond, say a team from the University of Idaho, according to a BBC report.

The study, which was presented to the American Association for the Advancement of science, showed how damage to rats' sperm caused by being exposed to garden chemicals remained in the genetic make up of their descendents four generations later.

Professor Cynthia Daniels, from Rutgers University in New Jersey, said that men who drank a lot of alcohol had been shown to have increased rates of sperm defects; and nicotine from tobacco found its way into seminal fluid as well as blood.

Professor Daniels said: "We need to open up our eyes and look at the evidence. My advice to young couples would be moderation. Substances that have an impact on reproduction are often also carcinogenic.

"If I was a young man I would not drink very heavily and not smoke two packets of cigarettes a day while I was trying to conceive a child."

Professor Neil McClure, a fertility expert at Queen's University Belfast said, "There is no doubt that if you smoke like a chimney or drink vast amounts of alcohol it will result in sperm damage, and probably damage in the DNA of the sperm. My advice to any man trying for a baby would be to lead as healthy a lifestyle as possible." 

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