Smoking & Drinking in Pregnancy May Multiply SIDS Risk
Fetal exposure to both alcohol and tobacco after the first trimester is tied to a 12-fold increased risk of sudden infant death syndrome (SIDS), according to a new study published in EClinicalMedicine, an online journal published by The Lancet.
These risks were in comparison to infants who were either not exposed to tobacco or alcohol in the womb or whose mothers quit tobacco or alcohol use by the end of the first trimester.
SIDS is the sudden, unexplainable death of an infant under one year of age. There is extensive scientific evidence showing that the risk of SIDS is increased by maternal smoking during pregnancy. Some studies also indicate that prenatal alcohol exposure, particularly from heavy drinking, can increase SIDS risk.
Now, the new Safe Passage Study, funded by the National Institutes of Health (NIH), offers new information into how SIDS risk may be influenced by the timing and amount of prenatal exposure to tobacco and alcohol.
“Ours is the first large-scale prospective study to closely investigate the association between prenatal alcohol and tobacco exposure and the risk of SIDS,” said first author Amy J. Elliott, Ph.D., of the Avera Health Center for Pediatric & Community Research in Sioux Falls, South Dakota.
“Our findings suggest that combined exposures to alcohol and tobacco have a synergistic effect on SIDS risk, given that dual exposure was associated with substantially higher risk than either exposure alone.”
To conduct the study, a team of researchers from the U.S. and South Africa formed the Prenatal Alcohol in SIDS and Stillbirth (PASS) Network. From 2007 until 2015, PASS Network researchers followed the outcomes of nearly 12,000 pregnancies among women from two residential areas in Cape Town, South Africa; and five sites in the U.S., including two American Indian Reservations in South Dakota and North Dakota.
The sites were chosen for their high rates of prenatal alcohol use and SIDS, and to include populations where the ethnic and socioeconomic disparities in SIDS remains understudied.
The researchers were able to determine one-year outcomes for about 94 percent of the pregnancies. They found that 66 infants died during that time, including 28 SIDS deaths and 38 deaths from known causes.
In addition to the almost 12-fold increased SIDS risk from combined smoking and drinking beyond the first trimester of pregnancy, the researchers found that the risk of SIDS was increased five-fold in infants whose mothers reported they continued smoking beyond the first trimester, and four-fold in infants whose mothers reported they continued drinking beyond the first trimester.
These risks were in comparison to infants who were either not exposed to tobacco or alcohol during gestation or whose mothers quit tobacco or alcohol use by the end of the first trimester.
In a joint statement, the leaders of the NIH Institutes that provide primary funding for the Safe Passage Study said, “These findings provide still more evidence of the vital importance of the early prenatal environment to healthy postnatal outcomes. Insofar as many women quit drinking and smoking only after they learn that they are pregnant, this study argues strongly for screening for substance use early in pregnancy and intervening as soon as possible.
“It also calls for stronger public health messaging regarding the dangers of drinking and smoking during pregnancy, and among women who plan to become pregnant.”
Pedersen, T. (2020). Smoking & Drinking in Pregnancy May Multiply SIDS Risk. Psych Central. Retrieved on September 30, 2020, from https://psychcentral.com/news/2020/01/21/smoking-drinking-in-pregnancy-may-multiply-sids-risk/153567.html