Health Problems Caused by Secondhand Smoke Smoking and Tobacco Use CDC Use of Electronic Vapor Products Before, During, and After Pregnancy Among Women with a Recent Live Birth Oklahoma and Texas, 2015 MMWR Vaping while pregnant could cause craniofacial birth defects, study shows In the United States, about 8% of all women who are pregnant smoke cigarettes, and another roughly 4% report using electronic cigarettes or vapes. To learn more about the dangers of smoking