One meta-analysis found an association between maternal alcohol consumption and atopic dermatitis in offspring.[1] Interestingly, it didn’t find an association between alcohol consumption and the skin condition for adults. It should be noted that these observations are based on a relatively small amount of research. It is possible that alcohol exposure in utero can lead to an immune system imbalance — called Th2 dominance — that is more associated with atopic dermatitis, but there may be other reasons.
There is some evidence that being born in winter or fall is associated with a greater prevalence of atopic dermatitis.[2] One probable reason for this is lower humidity and an increased risk of skin dryness and disrupted skin barrier function during the first months of life. Higher immune activity during winter has also been observed, which could increase the likelihood of excessive skin inflammation. Vitamin D levels are a plausible cause, but the evidence for this scenario specifically isn’t compelling.[3][4]
A meta-analysis found that a mother taking probiotic mixtures during pregnancy or breastfeeding can reduce the risk of atopic dermatitis in her children.[5] This provides evidence that the maternal gut microbiome during pregnancy is relevant to offspring, though evidence outside of the context of probiotic supplementation is lacking. Another meta-analysis, investigating the effects of Lactobacillus and Bifidobacterium bacteria mixtures in children, also found convincing evidence for a reduction in risk.[6] However, it should be noted that almost all studies included supplementation during pregnancy; only two studies didn’t. Yet another study looked at any probiotic supplementation and found notable benefits when women took probiotics during pregnancy. A total of 5 studies looked only at supplementation for infants; the results were positive overall, but we can’t be sure of them, and more research is needed.[7] The evidence for giving infants and children probiotics for prevention is promising but very preliminary.
Early-life antibiotic use is associated with a higher risk of atopic dermatitis, though this could be as a result of an increased risk of infections due to other factors that further increase the risk of the skin condition.[8]
Being overweight or gaining a large amount of weight during pregnancy is associated with a higher risk of atopic dermatitis in children, while low weight gain during pregnancy is associated with a lower risk.[9] These risks are small, and the extent to which the weight gain itself — rather than confounding factors, such as stress — plays a role is unclear.
Preliminary evidence suggests that maternal stress, anxiety, and adverse life events that could be causes of stress and anxiety are associated with a greater risk of atopic dermatitis in their children.[10]
There is also some evidence that prenatal phthalate exposure increases the risk. [11]
The gut microbiome seems to be critical early in life to the risk for atopic dermatitis. Probiotic use during pregnancy and breastfeeding are likely protective, while antibiotic use is associated with a higher risk. Adverse prenatal conditions, such as excessive weight gain, stress and anxiety, or exposure to alcohol or phthalates, are also associated with an increased risk.