A new Norwegian study supports previous findings that children delivered by cesarean section have an increased risk of developing asthma by age 3. This was particularly seen among children without a hereditary tendency to asthma and allergies.
The findings appear in the American Journal of Epidemiology.
Looking at data from more than 37,000 participants, the researchers studied the relationship between delivery method and the development of lower respiratory tract infections, wheezing, and asthma in the first 3 years of life. Children born by planned or emergency cesarean section were compared with those born vaginally.
The results indicated that children born by cesarean section have a slightly elevated risk for asthma at 3 years, but have no increased risk of frequent lower respiratory tract infections or wheezing. The increased risk of asthma among children delivered by cesarean section was higher among children of mothers without allergies.
“It is unlikely that a cesarean delivery itself would cause an increased risk of asthma, rather that children delivered this way may have an underlying vulnerability,” said Maria Magnus, primary author of the study and researchers at the department of chronic diseases at the Norwegian Institute of Public Health.
Children delivered by cesarean section may have an increased risk of asthma due to an altered bacterial flora in the intestine that affects their immune system development, or because children born this way often have an increased risk of serious respiratory problems during the first weeks of life.
Source. Norwegian Institute of Public Health