Risks Of Smoking When Pregnant Greater Than Risks Of Using Smoke-free Products
Dr. Marewa Glover
Centre of Research Excellence: Indigenous Sovereignty and Smoking
A review of studies on the effects of nicotine on pregnancy outcomes concluded that there is no reason to doubt that switching to smoke-free tobacco and nicotine products is better than continuing to smoke.
The paper, published in the international Harm Reduction Journal found some studies suggest that using non-smoked products containing nicotine during pregnancy is associated with an increased risk of some negative birth outcomes, but it remains clear the effect is less than that from smoking.
“There is strong evidence linking smoking while pregnant with negative effects on the health of a woman’s pregnancy and ill-effects on her infant. Despite knowing this, some pregnant women can’t stop smoking. In some countries it is now accepted practice to prescribe nicotine replacement products, such as nicotine gum, to help pregnant women quit” said lead author Dr Marewa Glover of the Centre of Research Excellence: Sovereignty & Smoking.
“Alternative nicotine products, such as snus, an oral tobacco product familiar in Scandinavia and the United States, or vaping nicotine, remains controversial. After doing this review, we understand why there is so much doubt among maternal care providers about supporting a pregnant woman to use any nicotine product – there are conflicting results.” She said.
The review was conducted by Dr Glover, an expert in smoking cessation and author of several papers on reducing smoking among Indigenous pregnant women, and Dr Carl Phillips, an epidemiologist with a similarly long career focused on tobacco harm reduction and epidemiological uncertainty.
Though over two hundred studies appeared to report on the effects of nicotine on pregnancy outcomes, the authors found only 21 that met their inclusion criteria requiring studies to be methodologically sound, conducted with humans, and testing the effects of nicotine delivered via non-combustible means.
Of the reviewed studies, 12 reported on the use of nicotine replacement therapies, 7 on Swedish snus, 1 on Alaskan iq’mik, and one on e-cigarettes.
“It would be so much easier for health professionals if we could quantify the risks for pregnancy of using smoke-free tobacco or nicotine products versus the risks of smoking, but the studies to date do not enable anyone to make such definitive statements." Dr Glover said.
“The truest conclusion at this time is that the pregnancy risks from using smoke-free products must be less than those from smoking, as most of the potentially harmful exposures from smoking are absent or dramatically reduced in the smoke-free products,” said Dr Glover.
The closing statement of the paper is that “the evidence does not support denying pregnant women use of smoke-free products if the alternative is that she would continue to smoke.”
The paper can be accessed free at: https://harmreductionjournal.biomedcentral.com/articles/10.1186/s12954-020-00359-2
Background Notes for Editors:
- Dr. Marewa Glover is one of New Zealand’s leading tobacco control researchers. She has worked on reducing smoking-related harm for almost 30 years and has over 100 scientific papers. She is recognized internationally for her research on reducing smoking among the Indigenous people of New Zealand, and particularly among Māori pregnant women. In 2019 she was named a finalist in the BlacklandPR 2018 Communicator of the Year Award and she was one of three finalists in the New Zealander of The Year Awards. Dr Glover is the most prominent public commentator on vaping in NZ. She is regularly called by the media and has appeared on NZ’s 60 Minutes in addition to participating in live online and conference debates about vaping. In 2018, Dr Glover established her own independent research centre the Centre of Research Excellence: Indigenous Sovereignty and Smoking.
- The Centre of Research Excellence: Indigenous Sovereignty and Smoking has an international focus on reducing tobacco related harms among Indigenous peoples globally. www.coreiss.com
- Dr Carl V Phillips is an advocate of tobacco harm reduction and for promoting a better understanding of the uncertainty inherent in epidemiologic studies. Over the course of his career he has received both research grants and consulting funding from producers of every one of the products mentioned in the review except iq’mik (most focused on issues related to tobacco harm reduction), as well as employment as a consumer advocate promoting tobacco harm reduction and very modest consulting income specifically related to birth outcomes and smoking.
- This project has been made possible with the help of a researcher-initiated grant from the Foundation for a Smoke-Free World, Inc. The contents, selection and presentation of facts, as well as any opinions expressed herein are the sole responsibility of the authors and under no circumstances shall be regarded as reflecting the positions of the Foundation for a Smoke-Free World, Inc.