The Hidden Link to Hormones, Fertility, and Disease
By Dr Herna de Wit, PhD
When it comes to women’s health, we often focus on hormones, reproductive organs, or gut health, and rightly so. But one crucial ecosystem is often left out of the conversation: the oral microbiome.
Emerging science is now shedding light on how the community of microbes in your mouth may influence everything from fertility and pregnancy to your long-term cancer risk. And as we move towards a more personalised, systems-based understanding of health, the mouth is beginning to take centre stage.
It turns out, your oral health may be telling a much bigger story than whether you need to floss more.
What Is the Oral Microbiome and How Does It Affect Women’s Health?
The oral microbiome refers to the diverse collection of bacteria, fungi, and other microbes that live in the mouth. Far from being passive passengers, these microbes play a key role in maintaining health or triggering disease throughout the body.
When in balance, the oral microbiome helps protect against harmful pathogens and keeps inflammation in check. But when disrupted through poor oral hygiene, stress, antibiotics, or other factors, it can become a gateway to systemic problems, particularly for women.
The Link Between Oral Bacteria and Women’s Cancer Risk
One of the most compelling areas of research involves the link between oral microbial diversity and cancer in women.
In a recent study involving non-smoking Mexican-American women, those with more diverse oral microbiomes were found to have a higher risk of developing cancer, particularly obesity-related types. Certain bacteria, including Fusobacterium and Prevotella, were more common in those who later developed cancer, while higher levels of Streptococcus seemed to be protective.
This challenges the assumption that microbial diversity is always beneficial. It also highlights how individual bacteria, and the context in which they exist, may matter more than only their variety.
How Oral Microbiome Imbalances Affect Fertility and Reproductive Health
The relationship between the mouth and the reproductive system is also gaining attention. Studies suggest that disruptions in the oral microbiome may contribute to fertility issues, including polycystic ovary syndrome (PCOS) and endometriosis. While the exact mechanisms are still being explored, chronic low-grade inflammation appears to be the common thread.
Inflammation originating in the mouth doesn’t stay there; it can spread via the bloodstream, influencing hormone regulation, immune responses, and even ovulation.
The Role of Oral Health in Pregnancy and Birth Outcomes
During pregnancy, most women’s oral microbiome remains relatively stable. But if harmful bacteria begin to flourish, it can raise the risk of complications.
Research shows that an overgrowth of bacteria such as Porphyromonas gingivalis, often associated with gum disease, may be linked to preterm birth, low birth weight, and preeclampsia.
It’s a sobering reminder that oral hygiene during pregnancy is not just about keeping your teeth clean. It may directly influence birth outcomes and your baby’s early development.
Does Menopause or the Menstrual Cycle Affect the Oral Microbiome?
Interestingly, studies suggest that hormonal fluctuations, such as those during menstruation or menopause, don’t significantly disrupt the composition of the oral microbiome.
However, other lifestyle factors can. Stress, diet, use of antibiotics, and even your geographic location can all subtly shift your oral microbial balance. Urban and rural environments appear to foster different microbial ecosystems, highlighting just how dynamic and sensitive the mouth can be.
Why Good Oral Hygiene Is Essential for Women’s Long-Term Health
We’re beginning to understand that the mouth is more than just a gateway to the digestive tract. It’s a mirror of systemic health. And for women, who already experience complex interactions between hormones, metabolism, and immunity, ignoring the oral microbiome could mean missing a crucial piece of the puzzle.
Whether you’re trying to conceive, navigating pregnancy, managing PCOS, or entering menopause, the health of your mouth may be influencing your journey more than you think.
How to Improve Your Oral Microbiome for Better Hormonal and Reproductive Health
Thankfully, the steps to nurture your oral microbiome are straightforward and powerfully protective:
- Brush and floss daily.
Mechanical cleaning removes biofilm and prevents bacterial overgrowth. - Use alcohol-free mouthwash.
Harsh antiseptics can disrupt beneficial bacteria. - Be mindful of antibiotics.
Antibiotics can disrupt the balance of both your oral and gut microbiomes. If you need to take them, support your recovery by reintroducing beneficial bacteria through a high-quality probiotic, live-culture kefir, or natural Greek yoghurt. - Manage stress levels.
Chronic stress influences salivary composition and microbial diversity. - Visit your dentist regularly.
Early detection of imbalances can prevent long-term issues.
Rethinking Women’s Health Through the Lens of Oral Microbiome Care
The science is clear: oral health isn’t just cosmetic, it’s foundational. Especially for women, who face unique hormonal and reproductive challenges, maintaining a balanced oral microbiome could be one of the simplest, most overlooked ways to support long-term health.
So next time you think about your health routine, don’t stop at skincare, supplements, or gut health. Ask yourself: What’s going on in my mouth?
Because sometimes, the key to better hormonal balance, pregnancy outcomes, or chronic disease prevention might just start with your smile.
References:
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- Marcickiewicz, J., Jamka, M., & Walkowiak, J. (2025). A Potential Link Between Oral Microbiota and Female Reproductive Health. Microorganisms. https://doi.org/10.3390/microorganisms13030619.
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