In this recent study published by the journal Respiratory Research, pregnant lab mice were exposed to secondhand smoke to study the effects it had on the lungs of their offspring. For the majority of their pregnancies, the mice were exposed to secondhand smoke and their offspring were exposed to clean, filtered air after they were born. The lasting effects of secondhand smoke were studied after the mice were about 4 months old when the mice were already considered in their adult stage.
Like a similar study meant to observe the effects of secondhand smoke on fetal liver cells, researchers found that the type of lung damage caused depended on sex. Male mice exposed to secondhand smoke were more susceptible to damage and had decreased lung volume compared to the females, possibly because the lungs of male fetuses develop more slowly than females. These results strongly suggest that human fetuses may suffer the same results if they’re exposed to secondhand smoke from their mothers as they develop.