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What happens when pregnant women smoke?

        Health | Pregnancy Issues

Toxic Chemicals
When a pregnant women inhales cigarette smoke, she exposes herself and her fetus to harmful chemicals.
When a pregnant women inhales cigarette smoke, she exposes herself and her fetus to harmful chemicals.
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The Incredible Number of Chemicals in Tobacco Smoke

There are more than 4,000 different compounds in your typical cigarette. Some of these compounds occur naturally in the tobacco plant, while others are added during the manufacturing process to add flavor or as preservatives. There is also a whole slew of chemicals created by combustion after you light a cigarette.

Many chemicals, including nicotine, can readily move from the mother's bloodstream into the fetal blood supply. (This is why physicians are so cautious about what over-the-counter or prescription drugs women take when they're expecting a child.) When a pregnant women inhales cigarette smoke, she exposes herself and her fetus to:

  • Nicotine - If you smoke while pregnant, your child will be exposed to almost the same level of nicotine as you. That means that once he or she is born and is no longer getting nicotine intravenously, the symptoms of nicotine withdrawal will likely set in.
  • Cyanide - Those who are old enough will remember the panic that ensued after someone laced Tylenol with cyanide back in the 1980s. Cyanide prevents cells from using oxygen for various metabolic processes, and it's one of the most deadly poisons around.
  • Cadmium - Found in rechargeable batteries, this heavy metal damages your kidneys. Without proper filtration and excretion by the kidneys, waste products from different cellular processes build up in your blood.
  • Arsenic - another heavy metal that interferes with the conversion of food (glucose) to fuel (ATP) inside your cells.
  • Formaldehyde - locks proteins in a rigid conformation. (For more information on formaldehyde, see Will aspartame make me go blind?)

With the exception of nicotine, there's not enough of any these chemicals in cigarette smoke to cause severe damage to either the smoker or their baby. It's more likely that all of these compounds in combination have the net effect of reducing the pool of nutrients and other resources that the fetus needs to grow. This may be one reason why babies born to smokers are smaller than average.