Antibiotics administration during last trimester of pregnancy is associated with atopic dermatitis - a cross-sectional study.

Introduction: Studies regarding antibiotics administration during pregnancy and atopic dermatitis (AD) in children are only few. In this context, the objective of our study was to investigate the potential association between the timing of intrauterine exposure to antibiotics or prenatal antibiotic administration in general and AD occurrence in children.

Methods: This was a cross-sectional study in 1046 subjects. The exposure to antibiotics during pregnancy was initially evaluated using simple logistic regressions. Then, each period of antibiotics administration was adjusted with the other periods of antibiotics exposure (model 1) and with the other variables associated with AD in our database (model 2).

Results: In simple logistic regression analysis, the administration of antibiotics during pregnancy, as a whole period, presented a trend of association with AD (OR = 1.28, %CI: 0.99 - 1.65). When we analyzed antibiotic administration during each trimester of pregnancy, only antibiotherapy during the 3rd trimester was associated with AD (OR = 2.94, %CI: 1.21 - 7.12). After adjusting with all the other important risk factors associated with AD in the database, antibiotics administration during the 3rd trimester of pregnancy was still independently associated with AD (OR=2.64, %CI: 1.01 - 6.91).

Conclusion: Antibiotic administration during the 3rd trimester of pregnancy was independently associated with AD in children.