C-section may not be right for allergic parents

Children born by cesarean section have an increased risk of developing asthma, particularly if they have allergic parents, according to a report published online Dec. 3 in Thorax.

Caroline Roduit, of the National Institute for Public Health and the Environment in Bilthoven, the Netherlands, and colleagues studied 2,917 children who were enrolled in a birth cohort study, 362 (12.4 percent) of whom developed asthma by age 8.

The researchers found that cesarean section was associated with an increased risk of asthma (odds ratio, 1.79), and that the association was stronger for children born to one or two allergic parents (ORs, 1.86 and 2.91, respectively) than for children born to non-allergic parents (OR, 1.36). In children delivered by cesarean section, they found a significant association with sensitization at the age of 8 only in those with non-allergic parents (OR, 2.14).

"Our results emphasize the importance of gene-environment interactions on the development of asthma in children," the authors conclude. "The increased rate of Caesarean section is partly due to maternal demand without medical reason. In this situation the mother should be informed of the risk of asthma for her child, especially when the parents have a history of allergy or asthma."

Roduit C, Scholtens S, de Jongste JC et al. Asthma at 8 years of age in children born by cesarean section. Thorax. Published Online First: 3 December 2008. doi:10.1136/thx.2008.100875