Going mainstream

In April 2018 the science division at National Public Radio (NPR) delved into the sensitive subject in an article highlighting the University of California, Davis Children’s Hospital—one institution that does prescribe probiotics to infants.

One of the conditions where probiotics are prescribed is premature births.

According to NPR: “At UC Davis Children’s Hospital, all preemies born under a certain birth weight are now given probiotics. It’s become a common practice in other countries including Australia, Japan, Sweden and Finland… but in the U.S., giving probiotics to preemies is controversial, with some doctors calling for more research.”

According to Dr Mark Underwood, chief of Pediatric Neonatology at UC Davis and a professor of pediatrics, when probiotics are given to premature babies the chance of getting a common type of inflammation called Necrotizing enterocolitis goes down. He knows this for sure as he’s conducted his own research.

2017 study

To conduct the the study Underwood and his colleagues recruited 68 moms and healthy babies. All of the babies were breastfed. Half of the babies were given probiotics during the first month of life. The other half—the control group—did not receive probiotic supplements.

The researchers reported finding an increase in the number of good bacteria among the babies given the probiotic.

Using fecal samples, researchers documented a 79 percent increase in levels of bifidobacteria, a type of bacteria that is thought to be protective. At the same time, Underwood and his team also measured a decrease in potentially harmful bacteria such as clostridium in the gastrointestinal tracts of the babies.

“One potential advantage of the bifidobacteria is that these bacteria can help lower the pH inside the intestines,” noted Underwood. “And a lower pH allows more healthy bacteria to thrive.”

2022 studies

In early 2022 a meta-analysis conducted in Spain found a reduction of 73% in gastrointestinal infections in babies delivered by Cesarean section when they were provided a probiotic regimen.

This is a promising finding since it is known that births by Cesarean section have a high likelihood of compromising immune system development of the newborn.

This happens because the surgical process disrupts the microbiota colonization process that occurs naturally through mother-to-infant transfer during vaginal delivery.

The researchers noted that this “microbiota disbiosyis” can be partly ameliorated by breastfeeding, when possible, but probiotic supplementing is an alternative strategy to improve immune response. 

The meta-analysis included 173 healthy C-section infants pooled from three double-blind, randomized, controlled clinical trials. Results of the study were published in Frontier in Pediatrics in July 2022.

Study – mothers can take “supplements for two”

A study later in 2022 found babies benefited when probiotic supplements were given to their mothers.

“This study demonstrated that small amounts of maternally ingested bacteria could translocate to the infant gut via oral and entero-mammary routes in more than half of the mother infant pairs, suggesting it is feasible to nourish infants with ​bifidobacteria and possibly other probiotic bacteria via lactation​,” the researchers wrote in Microbiome in November 2022.

To test the “bacteria transmission” effect the authors selected biomarker strains to track via transfer from mother-to-infant through breast milk.

Researchers recruited mother-infant pairs at the lactation stage, with mothers required to ingest a probiotic dry powder each day. The dose was ten times higher than normally recommended, but researchers noted this was crucial to enhance detection of the target strains.