A new study reveals that maternal psychosocial stress can negatively impact infant gut health. They found that high-stress mothers had a lower abundance of healthy gut bacteria in their infants, leading to an increase in pathogenic bacteria.
According to a recent study in Microorganisms, maternal psychosocial stress can affect the developing infant gut microbiome. Researchers examined mother-infant pairs in the Democratic Republic of Congo to investigate the impact of the mother’s psychosocial stress on the gut microbiome of the infant.
The establishment and role of the gut microbiome in human health have been the subject of recent research, but the mechanisms governing its establishment remain unclear. A healthy gut microbiome is vital for proper development of the immune system, central nervous system, and gut function in infants.
The study highlights the importance of understanding the impact of maternal psychosocial stress on infant health and development, particularly during the early stages of life.
The gut microbiome of an infant evolves quickly during the first 36 months, with a high strain turnover rate that corresponds to the transition from breast milk to solid foods. During the initial six months, the diversity and composition of the gut microbiome are particularly sensitive to environmental factors such as preterm birth, mode of delivery, and infection. While research on adults has revealed a link between the gut microbiome and psychosocial stress and depression, the impact of maternal psychosocial stress on the gut microbiome of infants during the first six months after birth is still not well understood.
For this study, researchers recruited mothers from Goma, DRC, who had uncomplicated vaginal deliveries and no medical conditions or infections. These mothers were willing to bring their babies to the hospital for follow-up visits, and informed consent was obtained after explaining the study in Congolese Swahili. Surveys and semi-structured interviews were conducted to collect medical histories and data on demographic factors, household conditions, trauma, maternal stress, and mental health. The questionnaire covered various topics, including violence, pregnancy, general and sexual trauma, post-traumatic stress disorder, perceived stress, postnatal depression, and anxiety.
At six weeks, three months, and six months after birth, fecal samples were collected from the infants. From these samples, the researchers extracted deoxyribonucleic acid (DNA) and amplified the 16S ribosomal ribonucleic acid (rRNA) gene. Using the data obtained, the microbial alpha and beta diversities were calculated, and the infants were categorized into low- and high-stress maternal groups based on the mother’s age, body mass index (BMI), weight and height, as well as the infant’s weight, length, and sex. The abundance of microbial species was then compared in these groups. The study found that infants with mothers who had high-stress scores had lower beta diversity in their gut microbiome at three and six months, while alpha diversity was higher at six months, compared to infants with mothers who had low-stress scores.
The researchers conducted a longitudinal analysis of the microbial diversity of the infant’s gut microbiome and found that at six weeks, infants born to mothers with high-stress levels had lower levels of probiotic and healthy bacteria, such as Bifidobacterium pseudocatenulatum and Lactobacillus gasseri, compared to infants born to low-stress mothers. However, no such differences were observed at three and six months.
Lactobacillus gasseri is known to reduce stress, fatigue, and inflammation, while Bifidobacterium pseudocatenulatum helps in modulating the gut-brain axis and prevents mood disorders.
Furthermore, high-stress levels in mothers were found to be associated with dysbiosis involving pathogenic bacteria such as Veillonella dispar and Megasphaera micronuciformis during the initial six months of the infant’s development.
In summary, the study examined the impact of maternal psychosocial stress on the diversity and composition of the infant’s gut microbiome during the initial six months of development. The results suggested that high levels of stress in mothers were associated with lower abundance of healthy, probiotic bacteria such as B. pseudocatenulatum and L. gasseri, which are essential in modulating inflammation, mood disorders, and the gut-brain axis during early growth and development. This decrease in beneficial bacteria resulted in an increase in the relative abundance of pathogenic bacteria, indicating that maternal stress may have a significant impact on the health and development of infants through changes in their gut microbiome.
Image Credit: Getty