By Jenny Hope
PUBLISHED: 17:58 EST, 23 May 2012 | UPDATED: 01:47 EST, 24 May 2012
Babies born by caesarean section are at double the risk of becoming obese children as those delivered naturally, researchers have claimed.
They said the obesity epidemic could be driven in part by rising rates of surgical deliveries.
The rate of caesareans in England is almost 25 per cent, which totals around 155,000 a year.
The operation can be life-saving for mother and baby but about 7 per cent of NHS surgical births occur for no medical reason.
In the US study, researchers from Boston Children’s Hospital examined 1,225 mother and child pairs over three years, weighing them and measuring the babies’ body fat. One in four of the deliveries was by caesarean.
After taking into account obesity in the mother and other factors, they found almost 16 per cent of children delivered by caesarean were obese by the age of three compared with 7.5 per cent born naturally.
The study, published in the Archives of Disease in Childhood journal, concluded that infants born surgically are not exposed to beneficial bacteria, and therefore their bodies take longer to accumulate good bugs that boost the body’s metabolism.
Obese adults tend to have fewer ‘friendly’ bacteria in their digestive tract and higher levels of ‘bad’ bacteria, which mean they burn fewer calories and store more of them as fat.
However, other studies show that obese women are more likely to need a caesarean, and are more likely to have children who grow up to be overweight or obese.
The researchers said mothers should be made aware of the potential health risks to the baby when choosing a surgical delivery if it is not necessary.
Sue MacDonald, of the Royal College of Midwives, said: ‘This highlights the need to avoid caesareans that are not medically needed.’