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

We are studying whether a probiotic supplement can promote the development of a healthy mixture of bacteria in breastfed babies born by caesarean section.

Start: September 2017

End: August 2021

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

The microbiome - coming into contact with 'good' bacteria during birth

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, birth is becoming more sanitised and the number of caesarean deliveries is increasing. This has made us concerned that some babies are not coming into contact with the “friendly” gut bacteria that they need.

Can a probiotic supplement help?

Breastfeeding is known to help develop “friendly” gut bacteria. In our PROMESA study, we are investigating whether the use of a probiotic supplement for 28 days can promote the development of a healthy mixture of bacteria in the guts of babies born by caesarean section, and if this can be maintained by breastfeeding until weaning at 6 months.

So far, 51 women and their babies have been included in the study. Babies will receive a daily supplement of either a probiotic or placebo in their mother’s breastmilk for 28 days.

We will follow the babies until they are 18 months old, analysing the health of their gut. In a sub-study, we will also assess the impact of the probiotic supplement on the babies’ immune systems.

Join the fight for healthy pregnancies and babies

Tommy's funds research across the UK investigating the reasons for miscarriage, stillbirth and premature birth, and fighting to make pregnancy and birth safer. We can keep you updated on ways you can support our work. If you would like to join our fight, click here.

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