Maternal vaginal microbiota may influence infant mortality risk: Study
As babies pass through the birth canal, they come into contact with the mother’s vaginal microbiome, where their skin is covered, and they feed on the first bacteria outside of the sterile uterus.
Women with certain chronic conditions, such as diabetes or high blood pressure, and those in low-resource neighborhoods with little access to health care and nutrition, have more risk of having an unhealthy vaginal microbiome. These unhealthy vaginal microbiomes have too many different types of bacteria, viruses or yeast which, unlike the intestinal variety, is a bad thing in the vagina, increasing the chances of infection.
According to the US Department of Health and Human Services, black women in the US have an infant mortality rate 2.3 times higher than white women, and this does not depend on education level. issues and income.
“We know what’s good for the mother’s health is good for the baby’s brain development,” said Tracy Bale, PhD, Professor of Pharmacology at the University of Maryland School of Medicine and director of the Center for Epigenetics. and on the other hand, stress contributes to an increased risk of disease. Research on Child Health & Brain Development. “We wanted to identify the biological factors that predict these negative health outcomes and determine how each contributes to these inequalities in our society.”
A few years ago, the Bale lab showed that pups delivered by caesarean section and given vaginal microbiota from stressed mouse mothers had differences in the way their brains developed and how they responded. responses to stress later in the environment compared with pups that were given probiotics from no stress. mothers.
Research into the human vaginal microbiome, led by Jacques Ravel, PhD, Professor of Microbiology and Immunology at the University of Maryland School of Medicine and Associate Director of the Institute for Genomic Sciences, found that microorganisms Human vaginal flora is divided into five different groups based on resident microorganisms. with four healthy variants and one ‘unhealthy’ group.
Dr Bale’s team wanted to know if this unhealthy vaginal microbiome could affect the baby’s development and birth outcomes, similar to previous mouse studies by Dr. surname. They tested this idea using vaginal microbiota samples from pregnant women in their C-section mouse model. First, they applied samples of healthy or unhealthy bacteria to the vaginas of mice to recreate the pregnancy environment.
Then, the C-section-born pups ingested the same microorganisms in the vagina that mimicked vaginal birth exposure. The researchers investigated which genes were turned on and off in the pups’ brains to see how the mother’s vaginal bacteria affected the pups’ development. They found that these pups soon activated and developed their immune systems.
Next, to more accurately model a vulnerable and low-resource population, the researchers repeated the study, but added the risk factors for prediabetes and obesity by swapping a pregnant rat’s normal high-fiber, low-fat chow for an unhealthy high-fat meal. , low fiber diet. 60% of the pups exposed to the unhealthy human microbiome and fed an unhealthy diet died within 48 hours of birth. However, with the same exposure to the microbiome but with a healthy fiber-rich diet, mortality was more than halved.
Dr. Bale says that soluble fiber, like that found in fruits and vegetables, ferments in the gut, allowing bacteria to produce short-chain fatty acids, which are essential for a baby’s brain development and are also essential nutrients. Effective anti-inflammatory for mothers.
Dr Bale said: “Vaginal microbiome composition leads to significant changes in the brain through fetal immune system development, and it appears that the immune system is overactive. This poses a risk of infant mortality. “In humans, we have observed these associations with unhealthy vaginal microbiota, but now our work is allowing us to make these connections and identify the underlying mechanisms.” final mechanism affecting pregnancy outcome, perhaps a new biomarker that can be used to identify women at risk.”
Dean E. Albert Reece, MD, PhD, MBA, Executive Vice President of Health Affairs, University of Maryland Baltimore, and John Z. and Akiko K. Bowers Distinguished Professors at the University of Maryland School of Medicine, said These studies help set the stage for what interventions can be tested to improve health and well-being and reduce infant mortality, particularly in vulnerable populations. our most vulnerable.”