The caesarean delivery rate continues to increase globally, especially in industrialised nations.1 Any attempt at reducing or reversing this trend has to consider both fetal and maternal risks and benefits of caesarean delivery. This has been the objective of many studies including that by Liston et al in this issue, which examines neonatal morbidity by method of delivery at term in both low- and high-risk women.2 The size of this study allowed the evaluation of rare outcomes (<1%). By confining the analysis to term, morbidity due to preterm birth was excluded, which allows truly delivery-related events to be studied. Caesarean delivery during labour was associated with an up to sixfold risk of depression at birth and up to threefold risk of neonatal respiratory morbidity, in comparison with spontaneous vaginal delivery. The risk of birth trauma was highest after assisted vaginal delivery, followed in decreasing incidence by spontaneous vaginal delivery, caesarean in labour and caesarean without labour.

Essentially, this study reflects a similar pattern as a large body of existing evidence—namely, that planned caesarean delivery has the advantage of eliminating certain risks of rare complications during labour and delivery at the expense of an increased risk of respiratory morbidity. The bulk of the respiratory morbidity caused by caesarean section is relatively mild, classed as transient tachypnoea of the newborn (TTN). Severe morbidity—namely, respiratory distress syndrome or pulmonary hypertension, are rare. However, TTN at term is associated with an increased risk of admission to hospital for asthma in childhood, and caesarean delivery …