Smoking and drinking during pregnancy could increase the risk of sudden infant death syndrome, according to a new study. The risk is greater if alcohol and tobacco are consumed together and beyond the first trimester.
How to explain sudden infant death syndrome? This syndrome, which is the leading cause of death in France for babies from one month to one year, corresponds to the sudden and unexpected death of the infant during his sleep. The causes of sudden infant death syndrome are still poorly understood.
American and South African researchers from Harvard University (Boston, United States), the Center for Pediatric & Community Research in Sioux Falls (United States) and the University of Stellenbosch (South Africa) are interested in one of the possible hypotheses: that of maternal consumption of tobacco and alcohol during pregnancy. They publish their study supervised by the American National Institute of Health (NIH for National Institutes of Health) on January 20, 2020 in the journal The Lancet.
12 times more risk of sudden death
For this study, the researchers worked on health data from 10,088 women and more than 12,000 fetuses. Of the total, 66 died, including 28 from sudden infant death syndrome. For all of these cases, the researchers noted the mothers’ alcohol and tobacco consumption during their pregnancy.
The result: the risk of sudden death is increased nearly 12 (11.79) times when the mother smoked and drank after the first trimester of pregnancy compared to mothers who did not smoke and drink or who quit before the end of the first trimester.
The effects of tobacco and alcohol seem to be cumulative since the risk factor drops to 3.95 when the mother drank but did not smoke and to 4.86 if she smoked but did not drink.
Understanding the action of toxins from alcohol and cigarettes
How to explain these results? For the moment, researchers do not know precisely the biological mechanisms explaining this correlation. On the one hand, they suspect alcohol and nicotine to alter the chemical circuits that control cardiorespiratory function, sleep and wakefulness.
On the other hand, they evoke the trail of the body’s immune, inflammatory and infectious response to these substances. Alcohol and nicotine could also act on the placenta and permanently harm the fetus.
“Further research is needed on how alcohol and smoke toxins work prenatal to cause sudden sleep-related death in postnatal time.”Write the authors in their study.
Screen for smoking and alcoholism as soon as you plan to become pregnant
And even if this study covers a small number of cases and does not prove a cause and effect relationship, it carries, according to the leaders of the NIH, an important health message.
“Since many women stop drinking and smoking only after finding out they are pregnant, this study strongly advocates screening for early pregnancy drug use and intervening as soon as possible.”They underline in a statement attached to the study.
They finally recommend “strengthened public health messages regarding the dangers of alcohol and tobacco consumption during pregnancy and among women planning to become pregnant“.