Promoting healthy gut bacteria in babies born by caesarean section: The PROMESA study

Tommy’s researchers are finding out whether a probiotic supplement can promote the development of a healthy mixture of bacteria in the guts of breastfed babies born by caesarean section.
  • Authors list

    Professor Rachel Tribe, Paul Seed, Dr Helena Watson, Jiadai Mi, Sarah Kheirallah, Dr Deena Gibbons, Dr Petter Brodin

    Start date: 2017 
    End date: 2021

  • Research centre

  • Research status

    Completed projects

This project took place at our London centre which operated between 1995 and 2021.

Why do we need this research?

Good bacteria in our gut help us digest food and get nutrition throughout life. The type of bacteria in a baby’s gut also influences how its immune system develops.

When babies are born vaginally, they come into contact with their mother’s vaginal and rectal bacteria, which helps them to build up good bacteria in their gut (microbiome). However, during caesarean deliveries, babies don’t come into contact with this ‘friendly’ gut bacteria. These babies are more likely to develop many immune-related conditions such as asthma, eczema and food allergies. They also have a greater chance of having type 1 diabetes or coeliac disease, compared to babies that are born vaginally, and the lack of exposure to good bacteria at birth is thought to be part of the reason why this happens.

With the numbers of caesarean deliveries increasing, we need to find ways of ensuring that babies get the gut bacteria they need for a healthy start to life.

What’s happening in this project?

Breastfeeding is known to help develop ‘friendly’ gut bacteria, with special sugars in breastmilk helping the bacteria grow. In the PROMESA study, our researchers are testing whether a probiotic supplement in addition to breastfeeding might help babies born by caesarean section.

In this study, babies are being given a probiotic supplement for 28 days (or a placebo) and mothers are receiving specialist support to help them breastfeed until their baby is weaned at six months. Our researchers are testing stool samples from the babies to see if their gut contains the friendly bacteria that they need. The babies will then have regular follow-up visits to assess their gut health until they are two years’ old.

In a separate part of the study, our researchers are also assessing what effect the probiotic supplement has on the babies’ immune systems.

What difference will this project make?

This project will find out whether probiotic supplements can help babies born by caesarean section get the friendly gut bacteria they need and will investigate what effect this has on their immune systems. Our researchers hope this will give these babies the best possible start in life.

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