Researchers have shown through a new study that there is a link between vaginal microbiome and the risk of preterm birth the lactobacillus crispatus bacterium said to be the major influencing candidate.
Researchers have published their findings in mSystems after analyzing data from a large study on pregnant women in North Carolina. They have shown that participants with a high abundance of Lactobacillus crispatus were less likely to have a preterm birth. The researchers also stratified their findings by race and found evidence for the protective effect of L. crispatus in both White and Black populations.
Lactobacillus bacteria are common in the vaginal microbiome, but the specific species that dominate may affect outcomes, said microbiologist and lead author Shan Sun, Ph.D., a researcher at the University of North Carolina Charlotte (UNCC).
In the gut microbiome, greater diversity is often associated with better health. But the opposite seems to be true in the vaginal microbiome, said bioinformatics scientist Anthony Fodor, Ph.D., at UNCC. “If you have one dominant microbe, ok, that’s what you want.” Higher diversity may dampen the protective effects of L. crispatus in Black women, said Sun, but further evidence is needed to probe that hypothesis. Sun is a postdoctoral researcher in Fodor’s lab.
Previous studies have investigated connections between the vaginal microbiome and preterm births, Sun said, but have largely been limited by low numbers of participants. The new findings are based on data on 464 White women and 360 Black women enrolled in the Pregnancy, Infection, and Nutrition (PIN) Study, based at the University of North Carolina Chapel Hill. Between 1995 and 2000, the study enrolled more than 3,000 women and compiled data on a wide range of health, environmental, and social factors.
However, it remain unclear whether L. crispatus is itself protective or is a consequence of some other factor that lowers the risk for preterm birth. Researchers still don’t know if having a specific vaginal microbiome creates a susceptibility for some other agent that’s actually the causal agent.