While many people now understand the importance of the gut microbiome, scientists have only recently begun to closely examine the microbiome of the cervix. In a new study conducted at Mumbai’s ICMR-NIRRCH, researchers revealed how “silent” infections can quietly alter the body’s immune environment and weaken the protective role of beneficial bacteria.
First Indian Study Using Advanced Genetic Sequencing
Between 2021 and 2023, scientists analysed the cervical microbiome of 43 sexually active, non-pregnant women aged 18 to 45. Using advanced genetic sequencing techniques, they mapped microbial patterns specific to this population.
Importantly, this marked the first such study in an Indian context, where demographic and ethnic factors may influence microbiome composition. The findings were published in the Indian Journal of Clinical Microbiology.
Hidden Infections Detected in ‘Healthy’ Participants
Although all participants appeared clinically healthy, laboratory analysis revealed a different picture.
Researchers found that 32.55% of the women had asymptomatic bacterial vaginosis (BV). Additionally, 16.27% had silent Candida (yeast) infections, while 13.95% harboured both infections simultaneously. These infections showed no outward symptoms but still altered the cervical environment.
Lactobacillus iners Dominates Healthy Cervix
Dr Deepti Tandon, lead author and gynaecologist at ICMR-NIRRCH, explained that the study built upon earlier work on the vaginal microbiome. This time, the team focused specifically on the cervix.
The researchers found that Lactobacillus iners dominated the cervical environment, accounting for 45.69% of the microbial population. These beneficial bacteria play a crucial role in maintaining women’s health and supporting immune responses against cervical and reproductive disorders.
Silent Infections Trigger Immune Alarm
However, when asymptomatic infections develop, they disrupt this protective balance. The study showed that these infections increase pro-inflammatory markers, effectively triggering a “chemical alarm” within the body.
As a result, the immune system shifts into a heightened state of alert. This persistent inflammatory response undermines the stability of the cervical microbiome and reduces the abundance of Lactobacillus iners.
Reduced Good Bacteria Linked to Inflammation
Dr Vikrant Bhor, co-lead of the study from the department of molecular immunology and microbiology, noted that women with asymptomatic infections showed significantly lower levels of Lactobacillus iners.
He emphasised that researchers had never previously mapped these microbiome variations in the Indian population. Moreover, he clarified that the team cannot yet determine whether the same findings apply to women who have not experienced childbirth. That question, he said, requires further investigation.
Nevertheless, the researchers successfully identified unique microbial “signatures” associated with each asymptomatic infection. They also correlated inflammation levels—key indicators of immune response—with the presence of specific Lactobacillus species.
Pathway to New Diagnostic Tools
Ultimately, the findings pave the way for improved diagnostic approaches. By identifying inflammation patterns and microbiome signatures linked to silent infections, scientists may soon develop targeted screening and early detection tools.
In doing so, this research not only expands understanding of the cervical microbiome but also opens new possibilities for preventive and personalised women’s healthcare.