Cesarean delivery and childhood respiratory outcomes

Childhood asthma and respiratory illness are health concerns that result in a significant burden on children, their families, and the healthcare system. Prior research has demonstrated an association between CD and short-term neonatal adverse respiratory outcomes, but less is known about the potential impact of mode of delivery on long-term respiratory outcomes.

To investigate whether there is an association between cesarean delivery (CD) and childhood respiratory outcomes.

Secondary analysis of a prospective, follow-up study of children delivered in the Antenatal Late Preterm Steroids study. Children were included if their mother was enrolled in the follow-up study and had data available for the primary outcome at age 6 or greater. The primary exposure was CD. The primary outcome was a composite of adverse childhood respiratory outcomes: abnormal spirometry, parent-reported diagnosis of asthma or of another chronic respiratory illness, or inpatient admission for respiratory illness. It was planned a priori to assess whether results differed according to whether or not CD occurred after evidence of labor. Log-binomial regression was used to calculate unadjusted and adjusted relative risks (RR), with vaginal delivery as the referent group.

Of 1,218 children enrolled in the follow-up study, 833 (68.4%) delivered vaginally and 385 (31.6%) by CD. The median gestational age at delivery was 36.1 (IQR 35.4-36.6) for those born by CD and 36.0 (IQR 35.3-36.7) for children delivered vaginally (p=0.90). Children born by CD had lower birth weight, were more likely to be small-for-gestational-age, have respiratory distress syndrome, and to be admitted to the neonatal intensive care unit, and were less likely to be breastfed. Women of children born by cesarean delivery were older and more likely to have private insurance. The median age at follow-up was 7 years in those born vaginally as well as in those born by CD. There was no difference in the primary outcome between children born by CD and those born vaginally (48.6% vs. 41.5%; adjusted relative risk (aRR) 1.14; 95% confidence interval (CI): 0.99, 1.31), although those born by CD were more likely to have had wheezing or whistling in the chest (49.4% vs. 40.2%; aRR 1.17; 95% CI: 1.02-1.34). There was no evidence that the association between CD and the primary composite outcome differed according to whether or not the CD was performed after labor.

Delivery via cesarean in children who were at risk for late preterm delivery was not associated with the primary composite of adverse respiratory outcomes.

Delivery via cesarean was not associated with a composite of adverse childhood respiratory outcomes.