Feeding newborns a 'small amount' of mother's faeces may reduce risk of allergies, study finds

The study has found a way to reduce the risk of allergies in newborns.
The study has found a way to reduce the risk of allergies in newborns. Photo: Getty Images/iStockphoto

Sometimes science can be pretty unpleasant, and many might find this one a little bit gross. But researchers say feeding a small amount of a mother's faeces to a newborn may help babies born via caesarean section ward off asthma and allergies. 

Previous studies have shown that babies born by c-section are more likely to develop asthma and allergies, partly because they're immune systems don't develop as well as they're not exposed to the microbiota in the mother's vagina and perineum during birth.

To combat this, some studies looked at the benefits of swabbing a newborn's skin with vaginal fluid immediately after birth to reduce this risk, but a new paper published in Cell has suggested going a step further to expose babies to their mother's microbiota; diluting a small amount of their mother's faeces in breast milk and feeding it to them just after birth.

"From a clinical point of view, this transfer of microbial material is happening during a vaginal delivery," says senior co-author Sture Andersson. "This is a gift the mother gives to her baby."

When a baby is born, the immune system is undeveloped, but starts to develop in response to microbial exposure. Although everyone's microbiota is different, but the way the bacteria colonises in the gut is different in babies born vaginally compared to those born by caesarean, and contributes to how the immune system responds to different outside stimuli, including potential allergens.

The researchers reported that the procedure appears to be safe, and babies examined at three months had a microbial makeup that looks more similar to babies born vaginally than to those born by caesarean.

The newborns were given the faecal microbiota transplants (FMTs) after they were born, with the he mothers' faecal samples collected three weeks beforehand. The babies' own faecal microbiota was tested at birth, then two days, one week, two weeks, three weeks, and three months.

The study found that by three months, the microbiotas of the babies who received the FMTs were similar to those of babies born vaginally.

Co-senior author Willem de Vos reminds people that it's something that should be conducted by a medical professional.

"It's very important to tell people that this is not something they should try on their own," he said. "The samples have to be tested for safety and suitability."