(NBC) - A new study reveals many pregnant women believe e-cigarettes are less harmful than tobacco.
Researchers at the University of Maryland surveyed over 300 expectant mothers visiting an OB/GYN clinic.
More than 40 percent said e-cigarettes were safer than traditional cigarettes, and only 57 percent knew that e-cigarettes contain nicotine.
Some of these devices also contain other chemicals and metals, which doctors say can harm a growing fetus.
Experts say e-cigarette education should be a routine part of prenatal care.
The American Vaping Association, which represents the e-cigarette industry, also states pregnant women should not use them.