The Scoop On Smoking from ACSH: what every teen should know about tobacco
Sometimes, a woman doesn't get pregnant even though she and her partner have been trying to conceive for many months. ("Trying" means having unprotected sex frequently.) Doctors call this problem infertility. Infertility can happen due to problems in the woman's body or in the man's body.
Toxic substances from cigarette smoke have been found in the semen (the fluid that contains the sperm) of smokers; they make their way there from the smoker's bloodstream. These toxic substances may damage the sperm. As a result, smokers have fewer sperm than nonsmokers do, and their sperm are more likely to be abnormal. Smoking may also modify the levels of reproductive hormones in men.
If a couple is having infertility problems and the man is a smoker, doctors usually advise the man to quit smoking, since this might increase the couple's chances of having a baby. Quitting smoking is actually a good idea for any man who wants to become a father, even if the man doesn't have infertility problems. Smoking by parents is bad for the health of their children. And of course, parents who smoke are harming their own health as well.
The American Council on Science and Health is a consumer eduction consortium with a board of 350 physicians, scientists, and policy advisors.