Smoking during pregnancy is a well-established cause of illness and death in the offspring, and there is emerging evidence that e-cigarette use during pregnancy may also affect perinatal outcomes.1
Nicotine from tobacco products adversely affects maternal and foetal health during pregnancy, contributing to poor outcomes including preterm delivery, still birth, neonatal apnoea, and sudden infant death syndrome.2,3 Laboratory and animal studies of nicotine and e-cigarette emissions have identified potential effects of e-cigarettes on perinatal outcomes. Results from several rodent studies suggest that maternal e-cigarette exposure during pregnancy, regardless of nicotine content, is linked to poorer health outcomes in both the mother and the offspring.4,5 These include a decrease in pup weights,6 foetal lung abnormalities7,8 and cognitive and behavioural defects in pups.5 Nicotine exposure during pregnancy also has lasting adverse consequences for brain and lung development.2
The US Surgeon General noted in 2014 that the evidence at that time was already ‘sufficient to provide appropriately cautious messages to pregnant women and women of reproductive age about the use of nicotine-containing products such as smokeless tobacco and electronic cigarettes, and newer forms of nicotine-containing tobacco products, as alternatives to smoking.’2
Six clinical studies have specifically investigated the effects of e-cigarette use during human pregnancy on the outcomes for babies.9-14 In four of these studies,9,11,12,14 e-cigarette use during pregnancy was associated with increased risk of having a small for gestational age (SGA) baby. SGA babies are in the lower 10th percentile of weight for their gestational age and at risk of conditions such as failure to thrive and hypoglycaemia (low blood sugar levels). SGA babies may have been affected by growth restriction during pregnancy, leading to increased risk of long-term health conditions later in life.15 One of the five studies found that e-cigarette use by pregnant women was associated with low birthweight and preterm birth after accounting for combustible cigarette smoking during pregnancy, but not specifically with SGA.13 Only the most frequent use (daily) of e-cigarettes was associated with these poor outcomes. These studies highlight the potential for e-cigarette use by women during pregnancy to lead to lower birthweight, but more comprehensive studies are necessary to make robust conclusions. In particular, the possibility that prior smoking of conventional cigarettes has affected outcomes must be addressed.
Although there are few studies and relatively small sample sizes, early findings indicate that e-cigarette users may have a lower chance of breastfeeding at discharge from hospital compared to never smokers,10 but similar risks of their babies being admitted to intensive care, gestation at delivery (39 weeks) and Apgar scores (a measure of a baby’s health after birth).10
A case-control study of infant neurobehaviour found that infants of mothers who used e-cigarettes but not conventional cigarettes during pregnancy had a greater number of abnormal reflexes and decreased motor maturity compared to unexposed infants.16 Caution is needed in interpreting these results due to other differences between the two groups of women, which may have influenced neurobehavioural outcomes for these infants.16
While some nicotine replacement therapy (NRT) products have been approved as safe by the TGA for use during pregnancy (see Section 22.214.171.124), the evidence for the safety and effectiveness of e-cigarettes for quitting smoking during pregnancy is less certain.17 A recent randomised controlled trial found that pregnant women who smoked, who were allocated to e-cigarette use or NRT, did not have a significantly different rate of cessation during pregnancy (6.8% for e-cigarettes versus 4.4% cessation rate for NRT). However when looking only at women who used their allocated product (i.e., excluding those in the NRT group who also used e-cigarettes), e-cigarettes appeared to be more effective (6.8% vs 3.6%).18 Adverse effects for women in both groups were similar.18 Nonetheless, treatment adherence and the overall cessation rates were low for both groups, highlighting an urgent need for research into effective cessation interventions for pregnant women. Among those who use e-cigarettes to try to quit, others have also noted the high proportion of long-term dual use of e-cigarettes and cigarettes, and an increased risk of relapse to smoking,19 which also require further research and consideration in pregnant women.20
Whilst there are no major studies examining the effects of e-cigarette use on fertility, one cross-sectional study has found that e-cigarette use is associated with a lower sperm count in younger men (mean age of 19.0 years).21 This finding is consistent with the effects of conventional cigarettes on sperm count, but more extensive studies are needed that consider prior use of conventional cigarettes by e-cigarette users.
Relevant news and research
For recent news items and research on this topic, click here. ( Last updated January 2023)
1. National Academies of Sciences Engineering and Medicine. Public health consequences of e-cigarettes. The National Academies Press, Washington, DC 2018. Available from: http://nationalacademies.org/hmd/Reports/2018/public-health-consequences-of-e-cigarettes.aspx.
2. U.S. Department of Health and Human Services. The Health Consequences of Smoking: 50 Years of Progress. A Report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014. Available from: http://www.surgeongeneral.gov/library/reports/50-years-of-progress/full-report.pdf.
3. England LJ, Bunnell RE, Pechacek TF, Tong VT, and McAfee TA. Nicotine and the developing human: a neglected element in the electronic cigarette debate. American Journal of Preventive Medicine, 2015; 49(2):286–93. Available from: https://www.ncbi.nlm.nih.gov/pubmed/25794473
4. Byrne S, Brindal E, Williams G, Anastasiou K, Tonkin A, et al. E-cigarettes, smoking and health. A Literature Review Update. CSIRO, Australia, 2018. Available from: https://researchnow.flinders.edu.au/en/publications/e-cigarettes-smoking-and-health-a-literature-review-update.
5. Mescolo F, Ferrante G, and La Grutta S. Effects of e-cigarette exposure on prenatal life and childhood respiratory health: A review of current evidence. Frontiers in Pediatrics, 2021; 9:711573. Available from: https://www.ncbi.nlm.nih.gov/pubmed/34513764
6. Orzabal MR, Lunde-Young ER, Ramirez JI, Howe SYF, Naik VD, et al. Chronic exposure to e-cig aerosols during early development causes vascular dysfunction and offspring growth deficits. Translational Research, 2019; 207:70-82. Available from: https://pubmed.ncbi.nlm.nih.gov/30653941/
7. Orzabal MR, Naik VD, Lee J, Hillhouse AE, Brashear WA, et al. Impact of e-cig aerosol vaping on fetal and neonatal respiratory development and function: vaping and neonatal respiratory development. Translational Research, 2022. Available from: https://www.ncbi.nlm.nih.gov/pubmed/35351623
8. Orzabal MR, Naik VD, Lee J, Wu G, and Ramadoss J. Impact of gestational electronic cigarette vaping on amino acid signature profile in the pregnant mother and the fetus. Metabolism Open, 2021; 11:100107. Available from: https://www.ncbi.nlm.nih.gov/pubmed/34355157
9. Wang X, Lee NL, and Burstyn I. Smoking and use of electronic cigarettes (vaping) in relation to preterm birth and small-for-gestational-age in a 2016 U.S. national sample. Preventive Medicine, 2020; 134:106041. Available from: https://www.ncbi.nlm.nih.gov/pubmed/32105682
10. McDonnell BP, Dicker P, and Regan CL. Electronic cigarettes and obstetric outcomes: a prospective observational study. BJOG, 2020. Available from: https://www.ncbi.nlm.nih.gov/pubmed/32036628
11. Cardenas VM, Cen R, Clemens MM, Moody HL, Ekanem US, et al. Use of electronic nicotine delivery systems (ENDS) by pregnant women I: risk of small-for-gestational-age birth. Tobacco Induced Diseases, 2019; 17:44. Available from: https://pubmed.ncbi.nlm.nih.gov/31516487/
12. Kim S and Oancea SC. Electronic cigarettes may not be a "safer alternative" of conventional cigarettes during pregnancy: evidence from the nationally representative PRAMS data. BMC Pregnancy Childbirth, 2020; 20(1):557. Available from: https://www.ncbi.nlm.nih.gov/pubmed/32967660
13. Regan AK, Bombard JM, O'Hegarty MM, Smith RA, and Tong VT. Adverse birth outcomes associated with prepregnancy and prenatal electronic cigarette use. Obstetrics & Gynecology, 2021; 138(1):85-94. Available from: https://www.ncbi.nlm.nih.gov/pubmed/34259468
14. Shittu AAT, Kumar BP, Okafor U, Berkelhamer SK, Goniewicz ML, et al. Changes in e-cigarette and cigarette use during pregnancy and their association with small-for-gestational-age birth. American Journal of Obstetrics and Gynecology, 2021. Available from: https://www.ncbi.nlm.nih.gov/pubmed/34864040
15. Australian Institute of Health and Welfare. Australia's mothers and babies. Canberra: AIHW, 2020. Available from: https://www.aihw.gov.au/reports/mothers-babies/australias-mothers-babies/contents/baby-outcomes/birthweight-adjusted-for-gestational-age.
16. Froggatt S, Reissland N, and Covey J. The effects of prenatal cigarette and e-cigarette exposure on infant neurobehaviour: A comparison to a control group. EClinicalMedicine, 2020; 28:100602. Available from: https://www.ncbi.nlm.nih.gov/pubmed/33294816
17. Claire R, Chamberlain C, Davey MA, Cooper SE, Berlin I, et al. Pharmacological interventions for promoting smoking cessation during pregnancy. Cochrane Database of Systematic Reviews, 2020; 3(3):Cd010078. Available from: https://pubmed.ncbi.nlm.nih.gov/32129504/
18. Hajek P, Przulj D, Pesola F, Griffiths C, Walton R, et al. Electronic cigarettes versus nicotine patches for smoking cessation in pregnancy: a randomized controlled trial. Nature Medicine, 2022; 28(5):958-64. Available from: https://www.ncbi.nlm.nih.gov/pubmed/35577966
19. Baenziger ON, Ford L, Yazidjoglou A, Joshy G, and Banks E. E-cigarette use and combustible tobacco cigarette smoking uptake among non-smokers, including relapse in former smokers: umbrella review, systematic review and meta-analysis. BMJ Open, 2021; 11(3):e045603. Available from: https://www.ncbi.nlm.nih.gov/pubmed/33785493
20. Bar-Zeev Y. Unclear role for e-cigarettes during pregnancy. Nature Medicine, 2022; 28(5):900-1. Available from: https://www.ncbi.nlm.nih.gov/pubmed/35577965
21. Holmboe SA, Priskorn L, Jensen TK, Skakkebaek NE, Andersson AM, et al. Use of e-cigarettes associated with lower sperm counts in a cross-sectional study of young men from the general population. Human Reproduction, 2020. Available from: https://www.ncbi.nlm.nih.gov/pubmed/32558890