This month’s blog post is a collaboration with Dr. Olga Carolina Rojas, MSc, PhD. She is a professor and researcher at la Universidad Autónoma de Nuevo León — specifically in the Department of Microbiology at the School of Medicine in Monterrey, Mexico. She also happens to be my sister!

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Did you know the vagina has its own ecosystem? Just like the gut, the vagina harbors millions of microorganisms—primarily bacteria—that work together to keep you healthy. The community of microorganisms living on our body surfaces and mucous membranes is called the microbiome; the specific community living in the vagina is the vaginal microbiome.

This microbiome is not static; it undergoes significant changes throughout your life, influenced by hormonal, physiological, and environmental factors. This system has been extensively studied due to its fundamental role in protecting the female genital tract, contributing to our understanding of vaginal homeostasis (balance) and the prevention of infectious and inflammatory processes. The healthy balance of the diverse microorganisms colonizing the vagina—mainly bacteria—is known as eubiosis. This vaginal balance can shift across different life stages—from birth, puberty, and sexual activity to menopause and old age—and can also be altered by conditions such as type 2 diabetes and obesity. 

The presence of vaginal bacteria has been documented for over a century. Until about a decade ago, the study of the vaginal microbiome was a new field; we have since discovered that this microbiome is essential for maintaining vaginal health. The key players in this balance are bacteria of the Lactobacillus genus. These bacteria produce lactic acid, which maintains the vagina's acidic pH during reproductive years and acts as a natural barrier against infections. The fungus Candida albicans also commonly coexists there without causing harm. 

During menopause, estrogen levels drop, and with that, the population of these protective Lactobacillus bacteria decreases. This change alters the vaginal environment: the pH—previously acidic and protective—becomes more alkaline, creating conditions that favor the proliferation of bacteria like Gardnerella vaginalis (the cause of bacterial vaginosis) and facilitating the entry of Escherichia coli, which is responsible for up to 80% of urinary tract infections. All of this can manifest as symptoms you may already be familiar with: vaginal dryness, itching, irritation, recurrent urinary tract infections, discomfort during sexual intercourse, and frequent infections such as bacterial vaginosis and vulvovaginal candidiasis.

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These changes are not simply "part of aging" that must be endured in silence. They impact your quality of life, sexual health, and emotional well-being—and there are solutions.

The good news is that we are learning more and more about how to care for and restore this ecosystem. And that is exactly what we will continue to discuss on this blog!