Trying to conceive? Whether you are a man or a woman, there are a lot of factors that influence your ability to make a baby, namely diet, exercise and lifestyle. But as it turns out, a new study shows that there are other factors to consider, particularly for men — factors that occurred even before you were born.  

A large-scale review of factors affecting sperm production found that whether or not a pregnant woman is exposed to certain pollutants (like cigarette smoke) could have a major effect on her unborn baby's ability to father a child in adulthood. Further, these studies found that smoking and exposure to pesticides and traffic pollution all do more harm in the first weeks of life than in the adult body. Thus, a male's fertility is damaged more if he is exposed to these pollutants in the womb than if he is exposed to them as an adult. And while damage done in adulthood can be undone by kicking bad habits, damage inflicted in the womb was probably permanent. This could be because exposure to toxins in the womb cuts the number of sertoli cells, highly specialized cells needed to help young sperm develop in to maturity during a man's adult life.  

Smoking certainly played a major role in the studies. Researchers found that smoking in pregnancy cuts sperm count by up to 40 percent. In contrast, a man who smokes heavily may have a sperm count only 10 percent lower than normal. 

Exposure to other environmental pollutants also played a role. A study of the after-effects of a major chemical leak from an Italian factory found no effect on the sperm counts of men who were adults at the time. But those who were in the womb grew up to have lower-than-expected sperm counts.

Of course, this doesn't mean that men are off the hook completely as adults. It doesn't matter if your a wanna-be-mom or a wanna-be-dad, if you're trying to conceive, you need to take care of your health, for your sake and for the sake of your future child. It does mean that when conception does occur, pregnant moms need to make every effort to protect their developing babies from toxins, for their sake, for the sake of their baby, and for the sake of their baby's babies.

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