Children born by Caesarean section are at greater risk of developing asthma than their peers, according to a major study into the impact of C-sections on child health.
Planned Caesarean births have hit record levels around the world, spurring experts from Aberdeen University to examine whether avoiding labour may disadvantage the child.
We must not overlook the impact of having a Caesarean on the woman. This is a major surgical procedureRCM director Louise Silverton
Using data from 300,000 Scottish births between 1993 and 2007, the authors rebuffed previous claims that there is an increased risk of obesity among children born by C-section.
Lead author Dr Mairead Black also found that children delivered by C-section were marginally more likely to die before the age of 21 than those who were born through labour, although she cautioned that this does not mean there is a causal link.
She said: “The current thinking is, if a baby is exposed to labour, then it is also exposed to ‘good bacteria’ that mothers pass on during the birth, and they are also exposed to a degree of natural stress at the time of birth that might make them more resistant to developing future illnesses.”
The World Health Organisation formerly recommended that no more than 15 per cent of deliveries should be C-sections but in the UK the figure is 26 per cent with almost half of these being pre-planned.
The study, published yesterday in the American Medical Association journal JAMA, shows that asthma involving a hospital admission occurred in 37 per 1,000 children born via C-section, compared to 34 per 1,000 in children born vaginally.
This means that for every additional 311 planned C-sections there is one more hospitalisation with asthma. Dr Black added: “This is an observational study, so we cannot definitively say that the planned C-section is the cause of the small increase in risk of asthma.
“However, this is a particularly robust piece of research that took several important factors into account, so we are confident in saying the delivery could be playing a role in the development of asthma.”
Louise Silverton, director for midwifery at the Royal College of Midwives (RCM), said the global increase in C-sections should be a cause for concern for both women and children but said more work must to be done to explore the issues in the study.
She said: “This adds to the growing body of evidence about the potential impacts on the baby of having a Caesarean section. We must also not overlook the impact of having a Caesarean on the woman. This is a major surgical procedure and one that should not be undertaken lightly.”