Infants born to mothers who smoked in pregnancy are at an increased risk of baby eczema according to research presented at a recent conference. The scientists presented their findings at the 2012 Annual Meeting of the American Academy of Allergy, Asthma and Immunology following investigation into smoking in pregnancy and passive smoking in pregnancy and the association with baby eczema.
Both atopic eczema and dermatitis are thought to be increased risks as smoking in pregnancy impairs the immune response of the growing foetus. It is not yet clear why this happens, or why babies born to mothers who smoked during pregnancy are more susceptible to atopic eczema/dermatitis syndrome (AEDS), but the researchers suggest that oxidative stress may play a role in the condition.
Specific Skin Effects of Smoking in Pregnancy
Numerous studies have examined the systemic effects on babies’ immune systems when their mothers smoked in pregnancy but this recent research found a specific effect on the babies’ skin. Lead researcher, Miwa Shinohara, a paediatric allergist, described the work done by her and her team as they investigated more than a thousand infants and their mothers using skin-prick tests, questionnaires, and physician-diagnosis of AEDS.
The babies averaged a year-old and the mothers thirty-one years old. Family history of allergy, prenatal and postnatal tobacco smoke exposure, and the number of siblings were also recorded in the study.
Previous work has found reduced lung function in babies exposed to tobacco smoke during gestation but recent findings of increased respiratory infections suggests that the immune system is also affected by smoking in pregnancy, which would tally with this apparent increase in risk of baby eczema or dermatitis.
Baby Eczema Risks Increased with Mothers who Smoke During Pregnancy
The overall cumulative rate of atopic eczema/dermatitis syndrome in the infants was 32.7% but this rate increased six-fold when the baby had been exposed to tobacco smoke between 28weeks of gestation and birth. Mothers smoking during their third trimester had an adjusted odds ratio for the occurrence of AEDS in their child of 0.214 if they smoked before their third trimester, with the AOR rising to 6.146 if they smoked between their 28th week of pregnancy and delivery.
Exact causes of baby eczema are unknown although there is a hereditary component to the condition and a clear connection between asthma, eczema, and allergy that is often found running through families. Further research is needed to elucidate the mechanisms behind this apparent increased risk of baby eczema caused by smoking in pregnancy.
American Academy of Allergy, Asthma and Immunology (AAAAI) 2012 Annual Meeting: Abstract 153. Presented March 3, 2012.