Smoking affects male fertility, experts say.

Sperm of heavy smokers lose critical ability to bind to an egg, University of Buffalo researchers claim.

Montreal – Air pollution and smoking can severely hamper a man’s ability to become a father – perhaps forever, experts at a conference on reproductive medicine said Tuesday.

“Male fertillity is at risk – and we have a better idea of what the potential causes are,” Peter Schlegel, director of the Society for male Reproduction and Urology and a professor at Cornell University, said.

Ït’s not just a risk to fertility, but to the offspring as well,” he added.

It’s not known how many men suffer, but lifestyle and environmental factors are known to contribute to low fertility, experts said at the American Society of Reproductive Medicines’s annual meeting.

Scientist from Sao Pulo, Brazil, prestnted data showing that fewer baby boys were born in heavily polluted urban areas compared with low pollution areas.

Animal studies confirmed the trend. More females were born after male mice exposed to polutants were mated with females who had been given clean air.

“The reason that occurs is that you’re changing the genetics of how sperm are made,”Schlegel said. “The exact defect is not know. But since the sperm determines whether you have a boy or girl, that clearly is a factor.”

Several studies have pointed to a trend – that sperm count among Western men has declined over the last 50 years.

Ïn some areas, like Athens, Greece, there’s good data to indicate a decline in fertility,”Schlegel said.

Other studies are not so clear, but male fertility is far more fragile that previously believed, Schlegel added.

“Reproduction, particlularly for men, is very sensitive to any adverse effects. Even a slight temperature increase for a brief period of time can drop his sperm production,” he said.

Researchers have know for a while that nicotine affects fertility but University of Buffalo scientists warned that the damage doesn’t end when smoking stops.

Sperm of heavy smokers lose the ability to bind tightly to an egg – a necassary step for fertilizaiton, said Lani Burknman, head of the anfology section of the universilty’s gynecology and obstetrics department.

“Specialized testing clearly reveals a significant drop in fertlity potential for men who are heavy tobacco smokers,” Burkman said, adding that only 18% of chronic smokers did not show defective sperm.

Just 11 cigarettes a day for six months cut fertility by two-thirds.

In fact, the more a man smoked, the less his sperm “Performed”

Nicotine alters the DNA in sperm, and faulty DNA can be passed along to the fetus, Burkman warned.

Preliminary studies suggest that in some men fertility isn’t restored when smoking stops.

It’s possible that chronic smokers will have permanent damage,’said Burknam.

In a separate study, obese men had 26% less testosterone then men of normal weight.