Annette Regan and colleagues recently expanded the range of adverse health effects associated with e-cigarette use to low birth weight babies for women who smoked during pregnancy. In their paper “Adverse Birth Outcomes Associated With Prepregnancy and Prenatal Electronic Cigarette Use,” published in Obstetrics and Gynecology, they used data from the national PRAMS (Pregnancy Risk Assessment Monitoring System) to assess the effects of e-cigarette use during the 3 months before pregnancy and the last 3 months of pregnancy.
They found that nonsmokers who used e-cigarettes during the last three months of pregnancy had an increased risk of delivering a low birth weight baby (OR 1.69, 95% CI 1.20-2.39). This risk is comparable to light cigarette smoking (1-10 cigs/day; OR 1.64, CI 1.31–2.07). Dual users (e-cigs and cigarettes at the same time) had similar risks to smoking.
Using e-cigs before getting pregnant did not affect pregnancy risks.
They collected their data from 2016 to 2018 which was before widespread use of Juul and other fourth generation e-cigarettes that deliver higher nicotine hits so they may be underestimating the effects of e-cig use. But even if the newer products do not have higher risks than the older less efficient e-cigs, the risk is substantial, particularly given the serious adverse effects of nicotine on the developing fetus.
These studies should convince the British National Health Service to reconsider its recommendation that pregnant women use e-cigarettes instead of cigarettes. They also need to reconsider their statement that nicotine is “relatively harmless” for developing babies.
More important, this is yet another risk that FDA needs to consider when deciding if authorizing e-cigs for sale is “appropriate for the protection of public health.”
Here is the abstract:
Objective: To evaluate the risk of adverse birth outcomes among adults who use electronic cigarettes (e-cigarettes) before and during pregnancy.
Methods: Data from the 2016-2018 PRAMS (Pregnancy Risk Assessment Monitoring System) were used to assess the association between e-cigarette use during the 3 months before and last 3 months of pregnancy among 79,176 individuals with a recent live birth and the following birth outcomes: preterm birth, small for gestational age, and low birth weight (LBW). Adjusted prevalence ratios were generated using average marginal predictions from multivariable logistic regression models. Models were stratified by prenatal combustible cigarette smoking and frequency of e-cigarette use (daily or less than daily use).
Results: In the 3 months before pregnancy, 2.7% (95% CI 2.6-2.9%) of respondents used e-cigarettes; 1.1% (95% CI 1.0-1.2%) used e-cigarettes during the last 3 months of pregnancy. Electronic cigarette use before pregnancy was not associated with adverse birth outcomes. Electronic cigarette use during pregnancy was associated with increased prevalence of LBW compared with nonuse (8.1% vs 6.1%; adjusted prevalence ratio 1.33; 95% CI 1.06-1.66). Among respondents who did not also smoke combustible cigarettes during pregnancy (n=72,256), e-cigarette use was associated with higher prevalence of LBW (10.6%; adjusted prevalence ratio 1.88; 95% CI 1.38-2.57) and preterm birth (12.4%; adjusted prevalence ratio 1.69; 95% CI 1.20-2.39). When further stratified by frequency of e-cigarette use, associations were seen only for daily users.
Conclusion: E-cigarette use during pregnancy, particularly when used daily by individuals who do not also smoke combustible cigarettes, is associated with adverse birth outcomes.
The full citation is: Regan AK, Bombard JM, O’Hegarty MM, Smith RA, Tong VT. Adverse Birth Outcomes Associated With Prepregnancy and Prenatal Electronic Cigarette Use. Obstet Gynecol. 2021 Jul 1;138(1):85-94. doi: 10.1097/AOG.0000000000004432. PMID: 34259468. It is available here.