A New Zealand case series published on August 11, 2026 reports that maternal vaping is turning up alongside sudden unexpected death in infancy, especially when a baby was sharing a bed with a parent.
The University of Auckland team behind the analysis says the pattern looks unsettlingly close to what smoking has long shown. The finding matters because vaping has been widely promoted as a safer swap for cigarettes, including for people trying to cut down in pregnancy.
The study does not prove that vaping causes infant death. It does place e-cigarettes on the same map as tobacco when a baby is in a bed-sharing environment.
What the researchers found
The team, led by Professor Ed Mitchell at the University of Auckland and Professor Barry Taylor at the University of Otago, analyzed 101 coronial cases of sudden unexpected death in infancy (SUDI) from 2022 and 2023.
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In 66 cases where information on maternal nicotine use and the infant's sleep setting was available, maternal smoking or vaping was reported in 72.7 percent, with vaping in 30.3 percent and smoking in 51.5 percent.
Around 72 percent of the deaths occurred while the infant was directly bed sharing. Vaping was more common in the bed-sharing group than in the rest, and 84.8 percent of bed-sharing deaths involved maternal smoking or vaping.
SUDI is an umbrella term for the sudden, unexpected death of a baby under one year old. It includes sudden infant death syndrome (SIDS) and accidental suffocation in a sleep setting.
Why the bed-sharing overlap matters
The interaction between maternal smoking and bed sharing has been documented for years. What is new is that vaping appears to be tracking the same pattern.
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"What is new and concerning is that vaping may be showing a similar pattern of risk as smoking, especially when combined with bed sharing," Mitchell said in the University of Auckland announcement.
He added that vaping has been "widely approached as a safer alternative to smoking and a smoking cessation aid, including in pregnancy," and that the findings suggest all nicotine exposure in pregnancy should be reconsidered when a baby also shares a bed.
Taylor pointed to a biological rationale that predates the vaping era. "Nicotine crosses the placenta, reduces foetal blood flow and lowers birthweight," he said.
He added that vaping may produce the same "arousal defect" seen in infants exposed to tobacco, meaning a reduced ability to wake in response to a breathing or oxygen problem during sleep.
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Taylor also framed the policy question bluntly. "When the possible consequence is an infant death, a precautionary approach is warranted while the evidence develops."
What this means in the US
Sudden unexpected infant death remains a significant cause of infant mortality in the United States. Roughly 3,700 such deaths were recorded in 2022, according to Centers for Disease Control and Prevention data, with around 41 percent classified as SIDS.
American guidance already treats bed sharing and prenatal nicotine as serious risks. The American Academy of Pediatrics does not recommend bed sharing under any circumstances and calls smoking a significant risk factor for SIDS.
Its safe sleep guidance advises parents, "Don't smoke or use nicotine during pregnancy or after your baby is born." It also recommends placing babies to sleep on their back, on a firm flat surface, in the same room but not the same bed as the parent for at least the first six months.
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The New Zealand analysis lines up with that guidance and pushes it a step further. If e-cigarettes carry a similar pattern of risk as tobacco, the "safer swap" framing that has helped market vaping in pregnancy needs a hard second look, the authors argue.
The practical takeaway for expectant parents
The researchers recommend a pregnancy-specific approach that treats nicotine-free as the goal, whether the source is a cigarette or a vape.
Coauthor Stephanie Cowan of Change for Our Children said support has to be practical. "Every woman who vapes or smokes during pregnancy needs support that meets them where they are in terms of their circumstances and confidence."
Parents who vape or smoke and are worried about cutting down during pregnancy or the first year of a baby's life should talk to their obstetrician or pediatrician. Cessation support in early pregnancy, together with a separate safe sleep space for the baby, is what current guidance points to.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.