Parents often wonder if a Caesarean section (C-section) affects their child’s health in the short or long term. Around one in three UK births are now by C-section, and often for very good reason: to keep mum and baby safe.
But research has suggested they might slightly influence a child’s development when compared to vaginal births. So, what does the science actually show?
When babies are born vaginally, they pick up helpful bacteria from their mum as they pass through the birth canal. This helps seed their gut microbiome – the community of microbes that play a vital role in immunity and health.
C-sections skip this step, and a major Lancet review found C-section babies had a higher chance of having allergies, asthma, and a less diverse gut microbiome in early life.
But most of the research was observational, showing links rather than clear cause and effect, and it’s uncertain whether these differences actually persist into later childhood.
Longer-term, the review reported slightly higher rates of obesity and asthma among children born by C-section, though evidence around cognition and education remains limited.
The picture is also mixed when it comes to the brain and behaviour. Some studies suggest C-section babies may be a little slower to reach early milestones, like movement or speech.
A 2023 Japanese study found modestly lower motor and language scores in C-section children up to the age of three. But it didn’t track outcomes later on, and these gaps usually close.
A UK study found small differences in thinking skills at nine months, but by the age of three, behaviour and development were no different.
One striking claim that has been talked about is that 80 per cent of C-section babies develop sensory processing disorder (SPD) – where children struggle with sensations such as noises or textures.
But this figure comes from a small Polish study of just 75 children, relying on parent questionnaires. Crucially, it doesn’t prove C-sections cause SPD.
Larger studies have found much smaller effects: a 2021 Chinese study of over 1,000 preschoolers found only a slightly higher risk of body awareness difficulties in C-section children, and mainly in boys. Other studies haven’t backed this finding.
Overall, most children born by C-section grow up healthy and thriving. While some research links C-sections to minor health or developmental differences, the evidence is far from conclusive, and any impact is likely to be small and temporary.
What is clear is that C-sections are often life-saving procedures, protecting mothers and babies when complications arise or requested by a mother for good reason.
For most families, the benefits far outweigh the uncertainties.
This article is an answer to the question (asked by Jane Martin, Southampton) 'How does being born by C-section affect a child's long-term health?'
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