Being born by Caesarean section may increase a baby’s risk of suffering from food allergies and diarrhoea in the first year of life, German doctors said on Thursday.

Researchers at the Children’s Hospital at Ludwig-Maximilians University in Munich found that babies delivered by Caesarean section were twice as likely to be sensitive to cow’s milk and other food allergens than infants born vaginally.

“We found an association between Caesarean delivery and diarrhoea and sensitisation in infants with a family history of allergy,” Dr Sibylle Koletzko said in a report in the journal Archives of Disease in Childhood.

The scientists followed the development of 865 babies for a year. Nearly 150, or 17 percent, had been delivered by Caesarean section.

The researchers suspect that in babies born by Caesarean section, the colonisation of natural bacteria in the gut, which promotes health and plays an important role in the immune system response, is delayed or altered.

Koletzko called for more research into the impact of Caesarean section delivery on infant health because it is becoming increasingly popular.