Research led by the University of Cambridge has found that the presence of Bifidobacterium breve, a common probiotic, in the gut of pregnant females can influence the placenta’s production of hormones and reduce pregnancy complications such as preeclampsia and miscarriage.
The study, published in the Journal of Translational Medicine, involved comparing pregnant mice with and without Bifidobacterium breve in their gut. Mice lacking this bacteria experienced higher rates of fetal growth restriction, low blood sugar in fetuses, and increased fetal loss. The research showed that Bifidobacterium breve plays a key role in stimulating the placenta to produce hormones necessary for supporting pregnancy.
This is reportedly the first time scientists have identified a connection between the gut microbiome and placental function. The findings suggest that testing and potentially modifying a pregnant woman’s gut microbiome could help identify and address complications such as gestational diabetes, preeclampsia, or miscarriage at an early stage.
“Our results open up an entirely new way to assess the health of a pregnant mother and her developing fetus by looking at the mother’s gut microbiome,” said Dr Jorge Lopez Tello, first author of the report who conducted his research at the University of Cambridge’s Department of Physiology, Development and Neuroscience.
He continued: “Everybody ignores the placenta - after nine months of pregnancy it just gets thrown in the bin. But now we understand more about how it works, in the future pregnancy complications like gestational diabetes, preeclampsia, miscarriage and stillbirth might be prevented simply by adjusting the mother’s gut microbes to improve the function of the placenta.”
The study found over 150 biological processes involving more than 400 proteins were different in placentas from mice with Bifidobacterium breve compared to those without. Mice with this bacteria had fewer pregnancy losses and their placentas were better at absorbing nutrients vital for fetal growth. These placentas also produced higher levels of important pregnancy hormones such as prolactins and pregnancy-specific glycoproteins.
Researchers noted that using mice allowed them to control for diet, activity, and other variables to isolate the effects of Bifidobacterium breve. While these findings are relevant to human pregnancies, further research is needed to determine how these bacteria interact within humans’ complex gut microbiomes and whether they can be safely manipulated during pregnancy.
Bifidobacterium breve occurs naturally in humans but its levels can be affected by factors like stress or obesity during pregnancy. It is also available as a supplement in probiotic drinks and tablets.
Up to 10% of first-time mothers experience babies with low birth weight or fetal growth restriction, which increases risks for conditions such as cerebral palsy in infants and mental health issues later in life.
“Our research reveals a whole new layer of information about how pregnancy works, and will help us find new interventions that can improve the chances of a healthy pregnancy for mother and baby,” said Professor Amanda Sferruzzi-Perri from Cambridge’s Department of Physiology, Development and Neuroscience and St John’s College.
Professor Lindsay Hall from University of Birmingham added: “It’s exciting to think that beneficial microbes like Bifidobacterium - which naturally support gut and immune health - could be harnessed during pregnancy to improve outcomes. Using something like a probiotic offers a promising alternative to traditional therapeutics, potentially reducing risks while enhancing wellbeing in mother and baby.”
The study was primarily funded by Wellcome.