In a direct fertility testing situation, we can show that two-thirds of smokers have lost some or a lot of their fertilizing capacity.

Specialized testing clearly reveals a significant drop in fertility potential for men who are heavy tobacco smokers.

Like other cells in the body, human sperm carry a receptor for nicotine, which means they recognize and respond to nicotine.

The men who failed were smoking about twice as many cigarettes per day, an average of 19 per day, compared to the smokers who passed the [test].

We've had it for a few months. We're testing it to see the effectiveness.

Some companies have terminated drug testing.