Infertility affects roughly 1 in 5 women of reproductive age in the United States, and for the millions trying to conceive, the search for answers can feel overwhelming. During National Infertility Awareness Week, we want to draw attention to an underexamined factor in reproductive health: the vaginal microbiome.

New analysis by Tiny Health reveals that vaginal microbiome imbalances are far more common than people realize, and published research suggests these imbalances may matter for fertility.

The science: microbiomes and fertility are closely linked

Many people are familiar with the gut microbiome and its wide-ranging effects on health. Less well known is the role of the vaginal microbiome — a distinct microbial ecosystem that research increasingly shows may have a direct bearing on reproductive outcomes.

A healthy vaginal microbiome is typically dominated by Lactobacillus bacteria, which maintain an acidic environment that protects the reproductive tract from harmful microbes [1],[2]. When Lactobacillus levels fall, other bacteria can take hold. In our analysis, 23% of samples showed elevated Gardnerella vaginalis and 22% showed elevated Prevotella, both microbes associated with bacterial vaginosis. These imbalances have been linked to reduced chances of natural conception and lower success rates with assisted reproductive technologies like IVF [3],[4].

The gut microbiome plays a supporting role too. Through what researchers call the gut–vaginal axis, the gut influences the vaginal environment via shared microbes, hormonal signaling, and immune crosstalk. Gut imbalances can disrupt estrogen metabolism and promote systemic inflammation, both of which affect the conditions in which eggs develop in the months before ovulation.

A clearer picture of reproductive health

Our Vaginal Health Test now includes fertility-specific condition associations, giving you a detailed look at the microbial patterns that research has linked to reproductive outcomes — along with actionable next steps. These insights are designed to complement clinical care, giving patients more to bring to the conversation with their providers.

The microbiome is modifiable — and that matters

One of the most important things to understand about the microbiome is that it can change. Unlike age or genetics, microbial balance is responsive to everyday choices, which means there are concrete steps individuals and couples can take to support their reproductive health while trying to conceive.

Diet: A fiber-rich diet with vegetables, legumes, whole grains, and fermented foods like yogurt and kefir supports beneficial gut bacteria and helps maintain estrogen balance. Limiting ultra-processed foods and added sugar reduces inflammation that can affect both gut and vaginal health.

Probiotics: Oral and vaginal probiotics containing specific Lactobacillus strains may help support a healthier vaginal microbiome. While evidence for direct fertility improvement is still emerging, a vaginal microbiome low in Lactobacillus is associated with lower fertility outcomes.

Lifestyle: Regular physical activity, consistent sleep, and stable blood sugar all support the hormonal and metabolic conditions that influence reproductive health. Avoiding douching and fragranced vaginal products helps preserve the natural microbial balance of the vaginal tract.

Knowledge is the first step toward action

For the millions of people trying to conceive, every piece of information matters. The microbiome has been an invisible variable for too long. Understanding it opens doors, whether someone is just beginning or has been trying to conceive for years. 

If you're on the path toward parenthood, you don’t have to navigate it alone. Our Tiny+ Prenatal Membership brings together gut microbiome and vaginal health testing and 1-on-1 coaching with a microbiome specialist, so you can understand what’s happening in your body and have support at every step.