Vaping and Using Nicotine Patches During Pregnancy Could Raise Risk of Crib Death, Rat Study Suggests

Expectant mothers who use nicotine during pregnancy could raise their baby's risk of crib death, according to a study using rats.

Scientific evidence already suggests smoking cigarettes during pregnancy raises the likelihood of crib death. But using nicotine replacement products, like e-cigarettes and patches, could also lead to crib death or sudden infant death syndrome (SIDS), researchers at Dartmouth's Geisel School of Medicine said. The chemical could affect a baby's central nervous system and cardiorespiratory functions, according to the study's authors.

SIDS is one of the leading causes of mortality in the first year of life. It refers to the unexpected death of an infant 12 months old or younger while sleeping. According to the Centers for Disease Control and Prevention (CDC), about 3,500 babies in the U.S. die suddenly and unexpectedly each year.

Being exposed to cigarette smoke or nicotine in the womb and during early life is thought to affect a baby's levels of the neurotransmitter serotonin, the authors noted. Scientists think serotonin defects could contribute to SIDS by affecting an infant's ability to autoresuscitate. This phenomenon, known as the Lazarus phenomenon, occurs when an individual's circulation restarts unaided after a cardiac arrest.

While the number of people who smoke has plummeted in the past decade, over 10 percent of pregnant women still light up, the authors of the study, published in The Journal of Physiology, said. The drop in cigarette smoking in turn correlates with a rise in smokers using nicotine patches and e-cigarettes, with more and more pregnant women using these products.

Currently, Food and Drug Administration officials believe there is not enough evidence available on the potential harm of e-cigarettes to recommend that pregnant women start vaping to quit cigarette smoking. But doctors may recommend FDA-approved nicotine replacement treatments for women who can't stop quit smoking cigarettes on their own.

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To test their hypothesis that nicotine is linked to SIDS, the researchers carried out tests on lab rats. They found that rat pups whose mothers were exposed to nicotine during pregnancy and carried the chemical in their maternal milk were more likely to have difficulties autoresuscitating.

The research indicates nicotine could affect a baby's central nervous system but also how their cardiorespiratory system reacts to stress—for instance, asphyxia—if they are caught in bedding or suffering from a minor illness.

But as the study was carried out on rodents, further research is needed to replicate the same results in humans. Even so, such studies offer a useful insight into the biology of mammals.

Stella Lee, an assistant professor in biology at Kansas State University and the corresponding author of the study, said in a statement: "Sudden infant death syndrome is such a distressing tragedy for families. We still don't fully understand the causes, but this research is important because it helps mothers reduce the risk."

Professor Janice Rymer, vice president of the U.K.-based College of Obstetricians and Gynaecologists, told Newsweek: "An important limitation of this study is that it involved exposing rats to nicotine. More research will be needed to determine the risks associated with nicotine use during pregnancy and the effect this may have on a baby while in the womb."

Rymer added that current evidence suggests e-cigarettes are much less risky than smoking.

"E-cigarettes do not produce tar and carbon monoxide, which are the main toxins in cigarette smoke. While the vapor from an e-cigarette does contain some potentially harmful chemicals also found in cigarette smoke, these are at much lower levels. Nicotine replacement therapy, which includes patches, contain only nicotine and none of the damaging chemicals found in cigarettes, so it is a much better option than continuing to smoke."

She added, "It can be very difficult to stop smoking, and e-cigarettes and nicotine replacement therapy offer women ways of giving up if they are unable to stop taking nicotine."

Since the 1990s, the number of SIDS cases has dropped after health officials issued recommendations saying babies should sleep on their backs. The CDC advises parents and caregivers to ensure that items such as pillows and blankets and toys are kept out of a baby's sleeping area and that infants don't share beds.