Snus, a smokeless tobacco product popular in the Nordic region, contains no combustion byproducts and is frequently used for prolonged periods of time between the upper lip and gum. Hence, despite being highly addictive and strong in nicotine, it is occasionally viewed as an alternative to both smoking and vaping.

According to a thorough study by the Swedish Karolinska Institute, children whose mothers smoked so-called "snus," the snuff or smokeless tobacco popular in Scandinavia, during pregnancy have a risk of SIDS that is more than three times higher.

"Fortunately, very few children suffer from sudden infant death syndrome, but we see that both snuff and smoking during pregnancy can be linked to increased risk," Anna Gunnerbeck, a pediatrician at Astrid Lindgren's Children's Hospital and researcher at the Department of Medical Epidemiology and Biostatistics at Karolinska Institute, said in a statement.

While the dangers of smoking during pregnancy have long been understood, there is a significant knowledge gap regarding smokeless tobacco varieties, which the researchers set out to fill.

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High quantities of nicotine are present in Nordic snus, but unlike cigarettes, no combustion products are produced. As a result, along with vaping and other smokeless nicotine alternatives, it is frequently regarded and promoted as being substantially less dangerous.
 
"In recent years, snus use has increased sharply among young women of childbearing age in Sweden. It is therefore important that women are informed about potential risks for fetuses and babies. Our study suggests that nicotine is a risk factor for sudden infant death and the conclusion is therefore that all types of nicotine products should be avoided during pregnancy," Anna Gunnerbeck concluded.
 
Last but not least, the researchers cautioned that it might be challenging to distinguish between the dangers that snus and smoking pose to the fetus from exposure to cigarette smoke and nicotine in breast milk after childbirth, as some of the mothers who quit consuming tobacco early in pregnancy may have resumed this habit later.

Snus is one of the most widely used tobacco products in both Sweden and Norway, despite the fact that it is largely prohibited in the EU with a few notable exceptions. Certain snus varieties contain a lot of nicotine and can quickly become addictive.