Research Highlight

Friendly bugs protect pregnant women

doi:10.1038/nindia.2020.85 Published online 13 May 2020

Researchers from the Translational Health Science and Technology Institute in Faridabad have identified four species of lactic-acid-producing bacteria that are dominant in the birth canal of healthy Indian pregnant woman1.  

They have found that the molecules secreted by these bacteria can modify the composition of other microbes, including disease-causing ones in the birth canal, and improve women’s health.

Such knowledge, the researchers say, may help understand how these beneficial bacteria maintain a healthy birth canal in pregnant women. Even such bacteria could potentially be used as biomarkers.

In India, about 3.6 million infants are born prematurely ever year. Microbes in the birth canal are thought to potentially influence the birth outcomes. However, it is not clearly understood how such microbes shape childbirth among Indian women.

To find out, the scientists, led by Bhabatosh Das and Shinjini Bhatnagar, analysed and sequenced the genomes of bacteria isolated from the vaginal swab samples of 40 healthy pregnant women from India.

They identified four dominant species of lactic-acid-producing bacteria: Lactobacillus iners, Lactobacillus crispatus, Lactobacillus gasseri and Lactobacillus paragesseri. The researchers say such bacteria possibly prevent the growth of pathogenic bacteria and reduce the risk of sexually transmitted diseases, and fungal and viral infections in the reproductive tract of women.

The Indian women’s vaginas were found to have low concentrations of Gardnerella vaginalis, a bacterium that has been linked to infection and preterm birth (PTB). Some unknown bacterial species, other than Gardnerella, may also induce PTB, says Das. Identifying such bacterial species would be a good biomarker for predicting PTB, he adds. 





1. Mehta, O. et al. Vaginal microbiome of pregnant Indian women: Insights into the genome of dominant Lactobacillus species. Microb. Ecol. (2020) doi: 10.1007/s00248-020-01501-0