Babies whose mothers have used snus (an oral tobacco product with nicotine) during pregnancy have a three times higher risk of suffering sudden infant deathaccording to an exhaustive study by the Karolinska Institutet (Sweden) published in the scientific journal Pediatric Research.
The risk was much lower if the mother had stopped taking snus before the first prenatal visit. The researchers conclude that all types of nicotine products During pregnancy.
Products with nicotine, but without combustion
“Fortunately, the incidence of sudden infant death is very low, but we see that taking snus or smoking during pregnancy is associated with increased risk,” explained Anna Gunnerbeck, a pediatrician at the Astrid Lindgren Children’s Hospital and a researcher at the Department of Medical Epidemiology and Biostatistics at the Karolinska Institutet.
Although it is known that smoking during pregnancy is a risk factor for sudden infant death, little research has been done on snus and other nicotine products.
To address this question, the researchers conducted a registry study that included more than two million babies born in Sweden between 1999 and 2019. During this time, only two in 10,000 babies suffered sudden infant death, which is when death occurs suddenly for no apparent reason during sleep.
Rhythm comparable to moderate smoking
When enrolling in the maternity registry, just over one percent of the mothers were taking snus and seven percent were smoking. Taking snus during pregnancy was associated with a 70 percent increased risk of infant death in the first year, regardless of cause, and a threefold increased risk of sudden infant death.
The risks associated with snus consumption were comparable to moderate smoking (one to nine cigarettes per day). The greatest risks were associated with smoke more than ten cigarettes up to date.
Dquit snus and cigarettes early in pregnancybefore the first appointment at the antenatal clinic, reduced the risk, compared with continued use.
Nicotine as a risk factor
Swedish snus is high in nicotine, but unlike cigarettes, does not contain combustion productsso it is considered, like vaping and other similar nicotine products, much less harmful to health.
“Given the spectacular increased consumption of snus among young women of childbearing age in Sweden in recent years and the growing popularity of e-cigarettes, it is necessary to inform women of the potential risk to fetuses and infants. Our study indicates that nicotine is a risk factor for sudden infant death, so we conclude that all types of nicotine products should be avoided during pregnancy,” Gunnerbeck said.
By linking different records, the researchers were able to adjust a number of important potential risk factors for sudden infant deathe, as the socioeconomic level and age of the mother. However, the researchers cannot establish any causal relationship, as there are unknown factors that could have influenced the results.
It’s hard to separate the risk to the fetus associated with snus and smoking from exposure to tobacco smoke and nicotine in breast milk after the baby is born. Furthermore, mothers who quit smoking or taking snus early in pregnancy might also have resumed the habit later. The researchers had no information on the amount of snus consumed during pregnancy or on the dose of nicotine that can cause harmful effects.
References
Gunnerbeck, A., Lundholm, C., Rhedin, S. et al. Association of maternal snuff use and smoking with Sudden Infant Death Syndrome: a national register study. Pediatr Res (2023). DOI: https://doi.org/10.1038/s41390-022-02463-4