Harmful When Pregnant Second hand Vaping Exposure Very Low Compared To Second hand Smoking A Thing Second Hand Smoke and Pregnancy American Pregnancy Association Study uncovers the hidden dangers of secondhand vape exposure to children Second hand smoke is highly toxic. Here's what happens when pregnant women and their babies are exposed to second hand smoke. Health Problems Caused by Secondhand Smoke Smoking and Tobacco Use CDC Secondhand smoke and secondhand aerosol