During intercourse, about 360 million sperm move through the vas deferens , where they are bathed in semen . Only 1 sperm will penetrate the egg. Not everyone will have all of the characteristics of the syndrome. The lifestyles of substance abusers can be confounded with substance abuse. New information on teratogens comes out every week.
Research quickly becomes outdated.
Don't get caught up in the media hype. Pull information from as many sources as possible. Compare and contrast what you find. Evaluate the credibility of the source - for example, the International Coffee Growers Association has vested interest in minimizing the affects of caffeine on pregnancy. By contrast, parenting magazines or networks, or organizaiton like the March of Dimes might have vested interest in overdramatizing the effects of certain substances in an attempt to help protect children.