The effects of gut health are far-reaching, affecting everything from your nervous and immune systems to your skin health. So it’s no surprise that your gut health also affects your fertility. What you consume, including a nutrient-rich diet, supplements, and probiotics, can all help to prepare your body for pregnancy and contribute to reproductive health. Read on to learn more about gut health, probiotics, and fertility.
- The importance of gut health
- Good gut health signs
- How to improve gut health
- Gut health and fertility
- Probiotics for gut health
- Probiotics and pregnancy
Why is gut health important?
The human body is home to over 30 trillion microbial cells—meaning we’re as many microbes as we are human cells. And there’s a huge relationship between the gut microbiota (which consists of bacteria, archaea, fungi, and viruses) and overall health. Known as “the gut microbiota axis,” our gut health influences the health of various systems in our body, including our nervous system, immune system, hormones, and metabolism—all of which affect fertility.
How does gut health affect other systems in the body?
With 70 to 80% of your immune system located in the gastrointestinal tract, the gut is a key player in your body’s defence, combating inflammation and protecting against disease. A healthy gut lining allows nutrients to be properly absorbed and keeps unwanted substances out of your bloodstream. Within the gut, microbes help to synthesize nutrients (like B vitamins, Vitamin K, and short-chain fatty acids), break down hormones (like estrogen), and influence metabolic health (think: blood sugar regulation and obesity). These processes in turn contribute to reproductive health, from sperm and egg quality to implantation (more on this later).
How do you know if you have good gut health?
When digestion feels smooth (regular, easy bowel movements), you’re not bloated frequently, your skin is clear, and you rarely get sick, your gut is probably in a good place. A healthy gut also means fewer sugar cravings, steady energy, and a balanced mood. Lastly, good gut health means good genital health: no recurring yeast infections, urinary tract infections, or bouts of bacterial vaginosis.
Signs of good gut health:
- Regular, easy bowel movements
- Infrequent bloating
- Clear skin
- Rarely sick
- Steady energy
- Limited food cravings
- No recurring yeast infections or urinary tract infections
- No bacterial vaginosis
How Does Your Vaginal Health Affect Your Fertility? →
How can you improve your gut health?
Eat gut-friendly foods
Most of us know that eating a diet rich in fruits and vegetables is important for fertility and well-being. It turns out that consuming 30 different plant foods per week helps to build a better microbiome. Rich in fibre, prebiotics, and polyphenols, plants serve as fuel for gut microbes so they can successfully populate the gastrointestinal tract while crowding out unwanted microbes. Similarly, fermented foods such as kimchi, sauerkraut, yogurt, and kefir can help to increase microbial diversity, reduce gut inflammation, and improve nutrient absorption.
Gut-health friendly foods
- Fruits and vegetables
- Fermented foods like kimchi and yogurt
- High-fibre foods like beans and whole oats
- Prebiotic foods like onions and garlic
Exercise daily
Moderate exercise enhances gut microbiome diversity, nutrient absorption, decreases inflammation, keeps hormones in check, and improves gut barrier integrity.
Reduce stress
Your nervous system is connected to your gut via the “enteric nervous system.” These stress signals depend on whether the body is in a sympathetic (fight or flight) or parasympathetic state (rest and digest). A stressed-out state sends stress signals to the gut. The effect is an imbalance of good-to-bad bacteria, leading to inflammation, dysbiosis, and leaky gut. The flip side? Engaging the parasympathetic nervous system (think: meditation, relaxation, and therapy) can help ease persistent gastrointestinal symptoms.
Practice good sleep habits
We know to scroll less before bed, but it turns out the impact goes beyond a bad night’s rest. Poor sleep—whether from electronic devices, jet lag, shift work, or stress—shifts gut microbiome composition. And, a disrupted gut can lead to issues getting enough good-quality sleep, too. Getting to bed and waking up with the rhythm of the sun, and ditching electronic devices, are two hugely impactful ways that can help.
Take a probiotic
Lastly, supplementing regularly with a high-quality probiotic can help to maintain and replenish beneficial bacteria–let’s break down the benefits!
What are probiotics?
Probiotics are supplements that contain live bacteria that colonize the digestive tract. Supplementation is especially useful following antibiotic use, which wipes out both harmful and beneficial bacteria. And while probiotics are not for everyone (like in individuals who are immunocompromised, those undergoing chemotherapy or with an autoimmune disease, and individuals with SIBO), a growing body of research shows that supplementation can improve health beyond the gut, especially when it comes to hormones and fertility.
What should I look for when shopping for a probiotic?
Not all probiotics are created equal: dose, strain, and shelf-stability are all factors to consider when choosing a probiotic that’s right for you. If you have specific health concerns that you’re hoping to support with probiotics, make sure to check in with your doctor who can help isolate the strains that will work best.
If you’re just getting started and interested in probiotics and fertility support, research shows that Lactobacillus and Bifidobacterium species, which dominate the gut, have hormonal and reproductive benefits for both males and females.
How does gut health affect female fertility?
Your gut microbiome helps regulate key hormones like estrogen and insulin, making it a major player in conditions like PCOS and endometriosis, and overall vaginal health.
Gut health and PCOS
Those with PCOS tend to have less bacteria that produce short-chain fatty acids (acids that go on to impact metabolic function), which worsens insulin resistance and inflammation, and disrupts ovulation. Supplementing with probiotics when you have PCOS can improve short-chain fatty acid production and in turn improve insulin resistance, inflammation, and ovulatory function, helping to get your cycle back on track.
Gut health and endometriosis
Those with endometriosis may also benefit from probiotic supplementation. This is likely because the gut is home to the “estrobolome”: a collection of enzyme-producing microbes that modulate and metabolize estrogen. In endometriosis, this process is malfunctioning, and supplementing with a probiotic containing Lactobacillus and Bifidobacterium species can help.
Gut health and vaginal health
Perhaps surprisingly, your gut microbiome also influences your vaginal and uterine health. Poor gut health can shift vaginal pH, reduce protective Lactobacillus, and raise your risk for bacterial vaginosis, yeast infections, and even implantation failure. A well-balanced gut supports a more receptive uterus, healthier cervical mucus, and a lower-risk environment for early pregnancy.
How does gut health affect male fertility?
Known as The Gut Endotoxin Leading to a Decline in Gonadal Function or GELDING theory, a growing body of evidence suggests just how influential the gut microbiome is on sperm health. Sperm, which are particularly sensitive to toxins due to their high fat content, can become inflamed from pathogenic gut microbes that leak into the rest of the body. The good news? In men with sperm issues, probiotic supplementation was found to improve sperm motility, morphology, sperm count, and even reduce sperm DNA fragmentation.
Should you take a probiotic while pregnant?
During pregnancy, probiotics support the maternal gut-immune axis, helping train baby’s developing immune system by promoting anti-inflammatory pathways. They also influence breastmilk microbiome through the enteromammary pathway (gut bacteria travel via the lymphatic system into breast tissue), so beneficial strains like Lactobacillus and Bifidobacterium can be passed on through breast milk to help seed the baby’s gut. This early microbial exposure plays a huge role in shaping newborn immunity and reducing allergy risk later in life. In the third trimester, supplementing with probiotics like L. rhamnosus and L. reuteri may lower a pregnant woman’s chance of testing positive for Group B Strep, a common vaginal bacteria that, if present during delivery, can pose risks for baby.
So, whether trying to conceive, or simply wanting to feel your best, small changes, like incorporating more plants and probiotics, can make profound impacts on gut health, which is foundational to everything.
