Understanding the Hidden Health Risks of Vaping UL Research Institutes 2nd Hand Vape Smoke And Pregnancy 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 Vaping in pregnancy Essential Parent Animal Study Shows Harmful Effects of Secondhand Smoke Even Before Pregnancy Duke Health Breast Cancer & E Cigarettes: Is Vaping a Safer Alternative to Smoking? Maurer Foundation