Research Indicates Pregnant Women Who Vape Are Exposed to Fewer Toxic Chemicals Than Smokers

Recent research conducted by scientists at City St George's, University of London, sheds new light on nicotine exposure among pregnant women. The study reveals that pregnant women who vape during pregnancy are exposed to significantly lower levels of toxic chemicals compared to those who continue to smoke cigarettes. Published in the journal Nicotine and Tobacco Research on June 21, 2025, the study highlights the potential for vaping to be a less harmful alternative for pregnant women trying to quit smoking.

The research involved 140 pregnant women recruited from five UK hospitals, categorized into five groups: exclusive smokers, exclusive vapers who previously smoked, those who both smoke and vape, individuals using nicotine replacement therapy, and women with no history of nicotine or tobacco use. Urine samples collected at routine antenatal visits were analyzed for nicotine and 14 volatile organic compounds (VOCs), which are key toxicants inhaled through smoking or vaping. VOCs are associated with increased risks for cancer, respiratory issues, and cardiovascular diseases.

Findings showed that women who vaped exclusively had substantially lower urinary levels of 10 VOCs—reducing exposure by 44% to 97% compared to exclusive smokers. Moreover, levels of 13 VOCs in women who vaped were comparable to those in women who had never used tobacco or nicotine products. Professor Michael Ussher, the study’s lead researcher, emphasized that while vaping appears to reduce exposure to harmful chemicals, it does not imply vaping is entirely safe during pregnancy.

The researchers caution that some toxins might still be present in vaping products, and vaping devices are consistently evolving, which could introduce new harmful substances. The study underscores the importance of ongoing research to fully understand the health implications of vaping during pregnancy. Overall, the findings suggest that vaping may be a less toxic alternative for women attempting to quit smoking while pregnant, but further studies are needed to assess potential health outcomes for both mother and baby.

This research was a collaborative effort involving institutions from the UK and the US, including the UK Centers for Disease Control and Prevention and the UK Health Security Agency. The team advocates for cautious interpretation of vaping as a harm reduction strategy during pregnancy and highlights the need for ongoing vigilance regarding emerging vaping toxins.