New research warns that vaping during pregnancy isn't as safe as many believe—nicotine, toxic aerosols, and oxidative stress could put newborns at risk for lifelong lung issues.
Review: Impact of E-Cigarettes on Fetal and Neonatal Lung Development: The Influence of Oxidative Stress and Inflammation. Image Credit: Reshetnikov_art / Shutterstock
In a recent review published in the journal Antioxidants, researchers in Italy evaluated the impact of e-cigarettes (E-Cigs) on fetal and neonatal lung development, focusing on oxidative stress and inflammation.
Background
Every breath a newborn takes marks the culmination of a complex developmental process, one highly susceptible to environmental influences.
While traditional smoking is well-documented for its harmful effects on fetal lung growth, e-cigs have emerged as a perceived ‘safer’ alternative, particularly among pregnant women. However, e-cig aerosols contain nicotine, solvents, and flavoring agents that may disrupt critical phases of lung formation.
The increasing prevalence of prenatal e-cig use—with studies showing up to 15% of pregnant women using these devices—coupled with limited research on its safety necessitates urgent investigation into its long-term impact on respiratory health.
Further studies are crucial to determine its role in neonatal lung dysfunction.
Stages of Lung Development and Vulnerability to E-Cig Exposure
Fetal lung development occurs in five key stages: embryonic, pseudoglandular, canalicular, saccular, and alveolar. These phases involve intricate cellular differentiation and structural organization necessary for postnatal lung function.
Environmental exposures, including maternal smoking and air pollutants, can impair this process, leading to reduced lung capacity, abnormal airway structure, and increased susceptibility to respiratory illnesses.
E-cig exposure introduces toxicants at critical developmental stages. Nicotine, for instance, readily crosses the placenta and accumulates in fetal lung tissue, altering normal cell signaling pathways essential for airway formation. Animal studies reveal nicotine concentrations in fetal blood can be eight times higher with certain e-cig devices (e.g., JUUL) compared to traditional cigarettes.
Additionally, solvents and flavoring agents in E-Cigs contribute to oxidative stress, a key driver of lung inflammation and dysfunction.
Stages of normal lung development and impact of adverse exposures.
Oxidative Stress and Inflammatory Response
Oxidative stress occurs when the production of reactive oxygen species (ROS) exceeds the body’s antioxidant defense mechanisms. E-Cig aerosols contain volatile organic compounds and fine particulate matter that generate oxidative damage. This can lead to inflammation, impaired alveolarization, and compromised lung elasticity in neonates.
Studies suggest that prenatal exposure to E-Cig aerosols triggers an inflammatory response characterized by increased levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). These pro-inflammatory markers can disrupt lung tissue remodeling, predisposing infants to respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD) later in life. Moreover, oxidative damage can interfere with pulmonary surfactant production—a process dependent on type II pneumocyte differentiation—which is crucial for lung function at birth.
Nicotine’s Role in Lung Dysfunction
Nicotine exposure during pregnancy is associated with several adverse pulmonary effects. It interferes with the Notch and Wnt signaling pathways, which regulate airway branching and epithelial cell differentiation. Animal studies reveal that offspring of nicotine-exposed mothers exhibit smaller lungs, delayed alveolar maturation, and increased airway resistance.
Additionally, nicotine affects mucociliary clearance, a critical defense mechanism against inhaled pathogens. Research indicates that nicotine exposure impairs ciliary function via TRPA1 receptor activation, leading to mucus accumulation and increased vulnerability to infections in newborns.
The role of e-cig-induced oxidative stress on the airways.
Impact of E-Cig Solvents and Flavoring Agents
Propylene glycol (PG) and vegetable glycerin (VG), the primary solvents in E-cigarette liquids, undergo thermal decomposition, releasing toxic byproducts such as formaldehyde and acetaldehyde. These substances contribute to airway irritation and damage to Deoxyribonucleic acid (DNA) in lung cells. Maternal exposure to PG/VG in mice reduces lung compliance in female offspring, highlighting potential sex-specific vulnerabilities.
Flavoring agents, often perceived as harmless, can also exert cytotoxic effects. Some flavors, such as cinnamon and vanilla, contain aldehydes that induce inflammation and impair normal lung cell function. Notably, multi-flavored E-Cig aerosols exhibit greater toxicity compared to single-flavor variants, emphasizing the potential risks of flavored vaping products during pregnancy.
Long-Term Consequences on Respiratory Health
Maternal smoking is a well-established risk factor for childhood respiratory disorders. Emerging data suggest that E-Cig exposure may pose similar risks. Studies in both human and animal models indicate that prenatal exposure to E-Cig aerosols leads to structural lung abnormalities, increased airway reactivity, and heightened susceptibility to respiratory infections.
Children born to mothers who used e-cigs during pregnancy have shown reduced lung function, increased rates of wheezing, and a higher likelihood of developing asthma. Additionally, E-Cig exposure may suppress immune responses by impairing antimicrobial defenses like CFTR function, further exacerbating respiratory vulnerability in neonates.
Prevention Strategies and Public Health Implications
A multi-faceted approach is necessary to reduce the risks associated with prenatal E-Cig exposure. Smoking cessation programs should emphasize the potential dangers of E-Cigs alongside traditional tobacco products. Healthcare providers must educate expectant mothers about the risks of vaping and offer support for nicotine addiction.
Legislative measures, such as restricting E-Cig sales to minors and requiring warning labels on vaping products, may help reduce use among pregnant individuals. Additionally, antioxidant supplementation, including vitamin C (shown to prevent DNA methylation changes linked to maternal smoking), has shown promise in reducing oxidative damage.
Conclusions
E-cigs pose significant risks to fetal and neonatal lung development due to their nicotine content, oxidative stress induction, and inflammatory effects. Nicotine disrupts key developmental pathways, while solvents and flavoring agents exacerbate airway damage. The long-term consequences include increased susceptibility to asthma, reduced lung function, and heightened vulnerability to infections.
Given the rising prevalence of E-Cig use during pregnancy, urgent public health interventions are needed. Smoking cessation programs, stricter regulations, and further research into antioxidant therapies could play a crucial role in protecting infant respiratory health. Comprehensive awareness campaigns are essential to dispel misconceptions about E-Cig safety.
Journal reference:
- Gambadauro A, Galletta F, Andrenacci B, et al. Impact of E-Cigarettes on Fetal and Neonatal Lung Development: The Influence of Oxidative Stress and Inflammation. Antioxidants. (2025), DOI: 10.3390/antiox14030262, https://www.mdpi.com/2076-3921/14/3/262