Oral health, the oral microbiome, and fertility: Why gum health matters for women and men trying to conceive

When couples begin preparing for pregnancy, the conversation usually starts with prenatal vitamins, cycle tracking, ovulation, egg quality, sperm health, nutrition, sleep, stress, and maybe labs. All of those matter deeply. But there is one area that is often left out of the fertility conversation: the mouth.

Your mouth is not separate from the rest of your body. It is home to a rich oral microbiome, a community of bacteria, fungi, and other microorganisms that can either support oral health or contribute to inflammation when out of balance. When the gums are inflamed, bleeding, swollen, or affected by periodontal disease, that local inflammation can become part of a much bigger systemic story.

And when you are trying to conceive, systemic inflammation matters.

Emerging research suggests that periodontal disease and certain oral bacteria may be connected with longer time to conception, unexplained infertility, adverse pregnancy outcomes, and altered reproductive function in women. In men, periodontal disease has been associated with lower sperm motility, abnormal sperm morphology, and increased sperm DNA fragmentation, all of which can influence fertility potential. This is not about blaming anyone’s mouth for infertility. It is about widening the lens and recognizing oral health as one more modifiable, supportive piece of preconception care.

At WeNatal, we often say fertility is a “we” journey, not just a “me” journey. Oral health is a perfect example of that. Both partners’ microbiomes, inflammation levels, and daily habits matter.

Key takeaways

• Oral health is a modifiable, whole-body factor that may belong in preconception care for both partners, not just a dental concern.
• In women, periodontal disease has been associated with a longer average time to conception, and some research in unexplained infertility has found higher antibody levels against certain oral bacteria.
• In men, periodontitis has been linked with reduced sperm motility, abnormal morphology, and increased DNA fragmentation, though findings on sperm count and concentration are mixed.
• Because sperm production takes roughly three months, supporting oral hygiene now may help support sperm quality in the months ahead.
• Professional dental care is considered safe during pregnancy, and simple daily habits like brushing, flossing, tongue scraping, and lowering added sugar can help reduce oral inflammation.

Not sure where to start with preconception health? The WeNatal quiz can help you and your partner find a first step: Take the WeNatal quiz.

Why oral health matters when trying to conceive

Periodontal disease, often called gum disease, is a chronic inflammatory condition that develops when the oral microbiome shifts toward more pathogenic bacteria. Over time, this can lead to bleeding gums, gum recession, pockets around the teeth, bone loss, and a persistent immune response.

One of the most important bacteria studied in this area is Porphyromonas gingivalis, often abbreviated as P. gingivalis. This bacterium is commonly associated with periodontal disease and has been studied for its ability to contribute to inflammation beyond the mouth. Researchers have explored its relationship with pregnancy complications, placental function, uterine changes, and fertility-related outcomes.

The key idea is simple: when the gums are inflamed, the body may be exposed to inflammatory signals, bacterial byproducts, and oxidative stress that can travel through the bloodstream. For couples trying to conceive, this matters because fertility depends on a delicate balance of immune tolerance, hormonal signaling, healthy blood flow, mitochondrial function, sperm quality, egg quality, implantation, and early placental development.

Oral health is not the only factor in fertility, but it may be a practical and often overlooked place to reduce inflammatory burden.

What does the research say about gum disease and time to conception in women?

One of the most cited studies on periodontal disease and fertility looked at time to conception in pregnant women. The study found that women with periodontal disease had an average time to conception of 7.1 months, compared with 5.0 months in women without periodontal disease. Among women who took longer than 12 months to conceive, periodontal disease was more common, affecting 34.9% compared with 25.7% of those who conceived in less than 12 months.

That difference of about two months can feel significant for anyone trying to conceive. When you are tracking ovulation, timing intercourse, waiting through the two-week wait, and holding hope month after month, two extra months is not just a statistic. It's an emotional time and can be a heavy mental load. It is more waiting.

The takeaway is not that gum disease is the cause of every delayed conception story. The more grounded takeaway is this: periodontal disease may be a modifiable risk factor worth addressing before pregnancy, especially for couples preparing to conceive naturally or through assisted reproductive technology.

P. gingivalis, unexplained infertility, and the oral-uterine connection

A 2025 Scientific Reports study brought even more attention to the possible oral health and fertility connection. Researchers compared serum IgG antibody levels against several periodontal bacteria in women with unexplained infertility and women who conceived spontaneously. Women undergoing infertility treatment had significantly higher antibody titers against several periodontal pathogens, including three strains of P. gingivalis.

The same study also used a mouse model of periodontitis associated with P. gingivalis infection. After four weeks, mice with periodontitis had an enlarged uterine cross-sectional area compared with healthy controls. The researchers also observed increased expression of estrogen receptor alpha and progesterone receptor in uterine tissues.

Why does that matter?

The uterus is not just a passive place where implantation happens. It is an active, hormonally responsive, immune-sensitive environment. Estrogen and progesterone signaling help prepare the endometrium for implantation, decidualization (a fundamental process in early pregnancy where the lining of the uterus undergoes a dramatic transformation to become a nurturing, protective, and bed for a fertilized embryo), and early pregnancy support. When inflammatory signals alter that environment, researchers are asking whether it may affect uterine receptivity and early pregnancy outcomes.

This does not mean that P. gingivalis is the hidden cause of all unexplained infertility. Human fertility is far more complex than that. But it does support a growing concept: the mouth and reproductive system may be connected through inflammatory, immune, microbial, and possibly extracellular vesicle signaling pathways.

Oral bacteria, implantation, and pregnancy health

P. gingivalis has also been studied in relation to pregnancy and placental biology. In animal research, P. gingivalis was able to reach the maternal-fetal interface and, in certain strains, was associated with impaired spiral artery remodeling and increased fetal loss. Spiral artery remodeling is one of the important vascular changes that helps support blood flow to the developing placenta.

Other research has explored how P. gingivalis may interact with trophoblasts, which are early placental cells involved in implantation and placental development. While much of this mechanistic research is still emerging and includes animal and cell studies, it supports the idea that oral pathogens can have effects far beyond the gums.

For anyone trying to conceive or preparing for IVF, this is why oral health deserves a place in the preconception checklist. It’s not separate from fertility care, it’s part of whole-body fertility care.

What about PCOS, hormones, and oral health?

The relationship between periodontal disease and hormone-related conditions is still being studied, but there are reasons to pay attention. Periodontal disease is an inflammatory condition, and conditions such as PCOS (PMOS) are also often associated with inflammation, oxidative stress, insulin resistance, and altered metabolic signaling. A systematic review found an association between periodontal disease and PCOS (PMOS), although more research is needed to understand cause, effect, and clinical implications.

This matters because many women trying to conceive are also navigating irregular cycles, insulin resistance, PCOS (PMOS), endometriosis, thyroid concerns, or unexplained infertility. Supporting oral health will not replace medical care, nutrition support, hormone evaluation, or fertility treatment. But it may be one more way to lower inflammatory load and support a healthier internal environment.

Now let’s talk about men: Gum health and sperm quality

Fertility is often framed as a women’s health topic, but sperm contributes half of the genetic material to an embryo. Sperm health matters for conception, miscarriage risk, IVF outcomes, and early embryo development.

A 2025 systematic review looked at the relationship between periodontal disease and sperm quality across nine studies including 1,386 men. The review found evidence linking periodontitis with reduced sperm motility, abnormal sperm morphology, and increased sperm DNA fragmentation. The findings around sperm count and concentration were more inconsistent, but the overall pattern suggests that periodontal disease may negatively influence several important sperm quality markers.

Another case-control study found that men with moderate or severe periodontitis had higher odds of abnormal semen parameters, even after adjustment for factors such as age and smoking. The reported odds ratio was 3.377, meaning moderate or severe periodontitis was associated with more than three times the odds of abnormal semen results in that study.

This is a big deal because sperm production takes about three months. That means the choices a man makes today, including oral hygiene, nutrition, smoking status, alcohol intake, sleep, heat exposure, and antioxidant support, may influence sperm quality in the coming months.

How gum inflammation may affect sperm motility, morphology, and DNA fragmentation

Sperm are highly vulnerable to oxidative stress. Their membranes contain delicate fats, and their DNA is tightly packaged but still susceptible to damage when oxidative stress is high. Chronic periodontal inflammation may contribute to systemic inflammatory cytokines and reactive oxygen species, which can interfere with sperm production and function.

For sperm, this can show up as:

• Lower motility, meaning fewer sperm are able to swim effectively toward the egg.
• Abnormal morphology, meaning sperm shape is altered in ways that may affect function.
• Higher DNA fragmentation, meaning breaks or damage in sperm DNA that may influence fertilization, embryo development, miscarriage risk, or ART outcomes.

The research is still developing, but the clinical message is practical: men should not wait until a semen analysis comes back abnormal to think about oral health. A dental evaluation and consistent oral hygiene routine can be part of a proactive three-month sperm health plan.

The oral microbiome is a couple’s fertility conversation

When we talk about preconception health, we often focus on egg quality, cycle regularity, prenatal nutrients, and blood sugar in women. Those are all essential. But the other half of the fertility equation matters too.

For men, oral health may be part of sperm quality. For women, oral health may be part of inflammation, uterine receptivity, pregnancy wellness, and microbiome balance. For both partners, oral health is part of the larger ecosystem of fertility.

This is also why it can be helpful for both partners to schedule dental visits before trying to conceive, before IVF, or before an embryo transfer. 

What to do before trying to conceive: A fertility-focused oral health checklist

Think of this as part of your preconception preparation, right alongside starting a high-quality prenatal, supporting sperm nutrients, optimizing vitamin D, eating enough protein, balancing blood sugar, and building stress resilience.

1. Schedule a comprehensive dental exam

Ideally, both partners should see a dentist before trying to conceive or beginning fertility treatment. Ask for a thorough gum evaluation, including pocket depth measurements, bleeding on probing, plaque assessment, and a conversation about signs of periodontal disease.

A practitioner who understands the connection between oral health, pregnancy, hormones, airway health, and the microbiome can be especially helpful. For some people, this may be an integrative or biological dentist, but the most important thing is finding a qualified dental provider who takes gum health seriously.

2. Treat bleeding gums as a signal, not “normal”

Bleeding when you brush or floss is common, but it is not something to ignore. Bleeding gums can be a sign of gingivitis or periodontal inflammation, and it is worth addressing before pregnancy when possible.

3. Brush consistently with a mineral-supportive toothpaste

Brush twice daily using a toothpaste that you tolerate and enjoy. Hydroxyapatite toothpaste is a popular fluoride-free option that supports enamel remineralization. Fluoride toothpaste is also considered safe and effective by mainstream dental organizations, so this choice can be individualized with your dental provider.

4. Floss or use interdental brushes daily

Brushing alone does not fully clean between the teeth. Floss, interdental brushes, or a water flosser can help disrupt plaque in the spaces where gum inflammation often begins.

5. Tongue scrape

The tongue can hold bacteria and debris that contribute to oral microbiome imbalance and bad breath. Tongue scraping is simple, inexpensive, and easy to add to a morning routine.

6. Consider xylitol gum after meals

Xylitol has been studied for its ability to reduce cavity-causing bacteria, especially mutans streptococci. In one follow-up study, children whose mothers used xylitol chewing gum had about a 70% reduction in dentinal caries at age five compared with children in fluoride or chlorhexidine groups.

This does not mean xylitol is a fertility treatment. It means maternal oral microbiome habits can influence the next generation’s oral health, which is a powerful reminder that preconception health can be generational.

7. Pay attention to mouth breathing

Mouth breathing can contribute to dry mouth, oral microbiome shifts, gum irritation, sleep disruption, and airway concerns. If you wake with a dry mouth, snore, struggle with nasal breathing, or suspect sleep-disordered breathing, it may be worth discussing with a dentist, ENT, myofunctional therapist, or airway-aware provider.

8. Support oral health through nutrition

The oral microbiome is influenced by diet. A fertility-supportive oral health pattern often includes:

• Protein at each meal to support tissue repair, immune function, and blood sugar stability.
• Colorful plants rich in polyphenols and antioxidants.
• Mineral-rich foods that provide calcium, magnesium, phosphorus, and trace minerals.
• Omega-3 fats to help support a healthy inflammatory response.
• Lower added sugar intake, especially sticky sugars and frequent snacking that feed cavity-associated bacteria.
• Adequate hydration and saliva support.

This is where oral health and fertility nutrition beautifully overlap.

If you are already pregnant: Oral health still matters

Pregnancy can change the oral environment. Rising estrogen and progesterone can increase gum sensitivity and make some women more prone to pregnancy gingivitis. Nausea, vomiting, reflux, food aversions, frequent snacking, and dry mouth can also affect enamel and gum health.

Professional dental care during pregnancy is considered safe. The American Dental Association states that regular and emergency dental care, including local anesthetics and radiographs when needed, is safe at any stage of pregnancy. ACOG also reassures patients that prevention, diagnosis, and treatment of oral conditions during pregnancy, including dental X-rays with appropriate precautions, are safe.

A practical pregnancy oral health plan may include:

• A gentle cleaning in pregnancy, often timed during the second trimester for comfort.
• A second cleaning later in pregnancy if gum inflammation, plaque buildup, or periodontal concerns are present.
• Rinsing with baking soda water after vomiting or reflux before brushing, because brushing immediately after acid exposure can be harsh on enamel.
• Continuing flossing, brushing, tongue scraping, hydration, and protein-rich meals.
• Working with your dentist and OB provider if you need treatment, imaging, or medication.

The goal is not to fear dental care during pregnancy. The goal is to keep inflammation low, support comfort, and protect both maternal and baby health.

Morning sickness tip: Protect your teeth after vomiting

If you are dealing with nausea, vomiting, or reflux, your teeth may be exposed to stomach acid. After vomiting, rinse with water or baking soda water, then wait about 30 minutes before brushing. This gives your enamel time to recover from the acid exposure.

A simple rinse can be made with water and a small amount of baking soda. Ask your dentist for individualized guidance if vomiting is frequent or severe.

The generational impact of a healthy oral microbiome

One of the most beautiful parts of this conversation is that oral health does not only affect the person trying to conceive. It may also influence the baby’s future oral microbiome.

The xylitol study mentioned earlier found that maternal xylitol gum use was associated with about a 70% reduction in dentinal caries in children at age five compared with fluoride or chlorhexidine groups. The researchers suggested this may be related to reduced transmission of mutans streptococci from mother to child.

That is generational health in action.

When you support your oral microbiome before and during pregnancy, you are not only caring for your gums and teeth. You may also be helping shape the microbial environment your baby is exposed to in early life.

What this means for IVF and fertility treatment

If you are preparing for IVF, IUI, egg retrieval, embryo transfer, or another fertility treatment, oral health can be added to your preparation plan.

This may be especially relevant if you have:

• Unexplained infertility.
• A history of miscarriage.
• Known periodontal disease.
• Bleeding gums.
• Bad breath that does not improve with brushing.
• PCOS (PMOS) or insulin resistance.
• Endometriosis or inflammatory conditions.
• Recurrent implantation failure.
• Abnormal semen analysis.
• High sperm DNA fragmentation.
• A history of smoking or vaping.
• A long gap since your last dental cleaning.

This does not mean delaying urgent fertility care to pursue perfect dental health. Fertility timelines are personal and often time-sensitive. But when possible, oral health evaluation can be integrated into the same preconception window where you are already optimizing nutrition, supplements, sleep, blood sugar, and lifestyle.

What we can say with confidence, and what we cannot

The oral health and fertility connection is promising, but it is still an emerging area of research. We can say that periodontal disease is associated with longer time to conception in some human research. We can say that women with unexplained infertility have shown higher antibody titers against certain periodontal pathogens in recent research. We can say that animal studies suggest P. gingivalis-associated periodontitis may affect uterine tissue, hormone receptor expression, pregnancy outcomes, and placental biology. We can say that periodontal disease has been associated with impaired sperm parameters, including motility, morphology, and DNA fragmentation.

We cannot say that gum disease is the sole cause of infertility, miscarriage, failed IVF, PCOS (PMOS), or poor sperm quality. We also cannot say that dental treatment alone will resolve infertility.

The most honest and helpful message is this: oral health is a modifiable, whole-body health factor that deserves a place in fertility preparation for both partners.

A simple preconception oral health plan for couples

If you are trying to keep this practical, start here.

• Both partners: schedule a dental cleaning and gum health evaluation.
• Daily: brush twice, floss or use interdental brushes, and tongue scrape.
• After meals: consider xylitol gum if tolerated and appropriate for you.
• Nutrition: prioritize protein, minerals, antioxidants, omega-3 fats, and lower added sugar intake.
• Airway: notice mouth breathing, snoring, dry mouth, or poor sleep and seek support if needed.
• Pregnancy: continue dental care and do not ignore bleeding gums.
• Fertility treatment: consider oral health part of your preconception or IVF preparation timeline.

Small steps, done consistently, can lower oral inflammation and support a healthier microbiome.

Frequently asked questions about oral health and fertility

Can gum disease affect fertility?

It may play a supporting role. In some human research, periodontal disease has been associated with a longer average time to conception, and women with unexplained infertility have shown higher antibody levels against certain oral bacteria. Gum disease is not considered a sole cause of infertility, but it is a modifiable, inflammatory factor worth addressing before pregnancy.

Does oral health affect sperm quality?

Research suggests it may. A 2025 systematic review linked periodontitis with reduced sperm motility, abnormal morphology, and increased DNA fragmentation, though findings on sperm count were mixed. Because sperm develop over about three months, supporting oral hygiene now may be part of a proactive sperm health plan.

Should both partners see a dentist before trying to conceive or IVF?

When possible, yes. Because fertility is a shared journey, it can be helpful for both partners to have a dental cleaning and gum evaluation before trying to conceive, before IVF, or before an embryo transfer. This does not mean delaying time-sensitive fertility care to pursue perfect dental health.

Is dental care safe during pregnancy?

Yes. The American Dental Association and ACOG consider routine and emergency dental care safe during pregnancy, including cleanings, local anesthetics, and dental X-rays with appropriate precautions when needed. Keeping oral inflammation low is part of supporting both maternal and baby health.

What is P. gingivalis, and how is it linked to fertility?

Porphyromonas gingivalis is a bacterium commonly associated with periodontal disease. Researchers have studied how it may contribute to inflammation beyond the mouth, including possible effects on uterine tissue, placental biology, and pregnancy outcomes in animal and cell studies. This research is still emerging and does not establish P. gingivalis as a cause of infertility.

How soon before conception should I address oral health?

There is no single rule, but the preconception window is a helpful time. Because sperm production takes roughly three months and gum inflammation can take time to improve, addressing oral health alongside nutrition, sleep, and supplements in the months before trying to conceive gives your body time to respond. Talk with your dental and medical providers for personalized guidance.

A note from WeNatal on oral health, fertility, and whole-body preconception support

At WeNatal, we believe fertility is not just about one hormone, one egg, one sperm, one lab value, or one supplement. It is about the whole ecosystem of health that helps create and sustain life. Oral health is part of that ecosystem. Your gums, microbiome, inflammatory balance, nutrient status, blood sugar, sperm health, egg health, and uterine environment are all connected in ways we are still learning to fully understand.

This is why we encourage couples to think beyond the basics. Yes, take a comprehensive prenatal. Yes, support sperm health. Yes, nourish your body with protein, omega-3s, minerals, and antioxidants. But also look at the often-forgotten foundations, including your mouth.

Because fertility was never meant to be carried by one partner alone. It is a shared journey, and sometimes the most powerful shifts begin with the simplest next step, like booking a dental cleaning, flossing tonight, and remembering that your whole body is worthy of care before pregnancy begins.

Support your journey side by side. Explore WeNatal for Her, WeNatal for Him, and WeNatal Together to help both partners fill nutrient gaps and support foundational health during preconception, pregnancy, and postpartum.