Study Says Feeding Newborns Faeces Boosts Immune System

by Laura Driver

Scientists claim that diluting a small amount of faeces in breast milk after birth could boost the way a baby's immune system develops

Previous research has shown that babies born via cesarean section are at a higher risk of developing asthma or allergies. A few studies have looked at whether swabbing a newborn's skin with vaginal fluid immediately after birth reduces the risk.

But researchers, based in Helsinki, Finland, decided to take a more drastic approach and find out if newborns could benefit from faecal microbiota transplants (FMTs). Their findings, published in the journal Cell, showed that at three months, the newborns had a microbial makeup resembling babies born vaginally.


Co-senior author Sture Andersson, of the University of Helsinki and Helsinki University Hospital in Finland, said: "From a clinical point of view, this transfer of microbial material is happening during a vaginal delivery.

He explained that at birth, the immune system is underdeveloped, but once a baby begins living in the outside world, their immune system matures in response to microbial exposure.

Although every person's microbiota is individualised, the overall patterns of which bacteria type colonise the gut differ between babies born vaginally and those born by C-section. These variations appear to make a difference in how the immune system learns to response to outside influences, including potential allergens.


For their study, the women were recruited with leaflets places in doctors' waiting rooms. Around 30 mums-to-be contacted the researchers to find out more and 17 eventually agreed to participate. However, 10 were found to have contraindications - such as a recent course of antibiotics or a potentially dangerous microbe. Ultimately seven mothers who were scheduled to have C-sections took part in the experiment.

The women's faecal samples were collected three weeks before their delivery date and the babies were given the FMT shortly after birth.

The newborns stayed in hospital for two days afterwards to make sure there were no complications, as well as having blood tests. Their own faecal microbiota, known as the meconium, was tested at birth and again at two days, one week, two weeks, three weeks, and 12 weeks. The researchers found that by the time they were three months old, their microbiotas were similar to those of babies born vaginally.


As a baseline for these comparisons, the researchers used data collected previously at the same hospital, as well as global datasets.

Co-senior author Willem de Vos, of the University of Helsinki, said: "This was not designed as a safety study, but we found it to be effective and supporting the concept of vertical transfer from mother to baby. "However, it's very important to tell people that this is not something they should try on their own. The samples have to be tested for safety and suitability."

The researchers also pointed out that while the research may sound unpalatable to some people, the mothers who agreed to participate in the study were very motivated.


One woman who was having twins was told the FMT could be giving to one baby, with the other one used as a sort of control. However, she declined, stating that she didn't want one of her babies to have an unfair advantage by receiving the transplant.

In future work, the researchers plan to study the development of the immune systems in C-section babies who receive FMTs and compare it to those who don't. Unlike the current study, which was observational, the future studies will have a control group and will be blinded to the mothers.

If you enjoyed reading this article why not share it with others!

Written by

Laura Driver

Blogger & Social Media Manager
Laura lives in Yorkshire, UK with her two teenage children. When they were little (and definitely not taller than her) she used to blog avidly about the trials and tribulations of motherhood. Laura is no stranger to all the joys small children can bring; sleepless nights, a random public meltdown or a spectacular poonami. She fondly remembers the time her youngest child rolled across a supermarket carpark in a trolley while she was putting her eldest child in the car and the time her, then, three year old took up swearing at a church event. Laura has worked for Your Baby Club, as a Social Media Manager, since 2014.

Articles on are a mixture of informative pieces, anecdotal accounts and professional advice from our panel of Bloggers, Writers and Experts. The views and opinions expressed in these articles are those of the authors and do not necessarily reflect the official view of Your Baby Club UK

Related articles