The Use of Electronic Cigarettes in Pregnancy: A Review of the Literature.

Importance: Electronic cigarette (e-cigarette) use in pregnancy has been steadily increasing and has been hyped as being a safe alternative to cigarette smoking during pregnancy. This review discloses what is currently known about e-cigarette use in pregnancy and the effects of its use on pregnancy outcomes.

Objective: To determine what is currently known about the prevalence of e-cigarette use in pregnancy and the effects of e-cigarette use on pregnancy and perinatal/neonatal outcomes.

Evidence Acquisition: A PubMed, CINAHL, and EMBASE search was undertaken using the search terms "pregnancy" OR "pregnancy complications" OR "pregnancy outcome" OR "newborn" OR "neonate" OR "birth" AND "electronic cigarettes" OR "e-cigarettes" OR "ecigarettes" OR "vaping" OR "vape." The search was limited to the English language and between 2007 and October 12, 2017.

Results: The search identified 91 articles, 40 of which are the basis for this review. The prevalence of e-cigarette use is 0.6% to 15%. The amount of nicotine consumed by e-cigarette users is comparable to that consumed by cigarette smokers. Most of the animal model studies suggest a potential danger to the developing fetus primarily because of the nicotine consumed and that consumption has multiple effects on the immune system, neural development, lung function, and cardiac function. There is a widespread flawed perception that e-cigarettes are safe to use during pregnancy.

Conclusions: The marketing of e-cigarette use as a safer alternative to cigarette smoking has led to an increasing use even in pregnancy. The nicotine consumed by e-cigarettes is similar to that consumed by cigarette smoking. Animal studies confirm the dangers of nicotine to the developing fetus. More research needs to be done specifically assessing e-cigarette use, pregnancy, and pregnancy outcomes.

Relevance: The amount of nicotine consumed in cigarette smoking is similar to the amount of nicotine consumed with e-cigarettes. The effects of nicotine exposure during fetal development are well known and include effects on multiple organ systems.