We’ve all heard that “health starts in the gut,” but it turns out this couldn’t be more true, especially when it comes to fertility. Your gut isn’t just responsible for digestion; it plays a powerful role in everything from hormone balance and immune function to mood and nutrient absorption. And yes, it can even impact your ability to conceive and support a healthy pregnancy.
Research is now showing just how deeply connected our gut health is to reproductive health. Whether you’re preparing to grow your family, already pregnant, or healing postpartum, supporting your gut can help support hormone health, calm inflammation, and make sure your body is getting the nutrients it needs, all of which are key for a healthy fertility journey.
The gut-fertility connection: What science says
Gut inflammation and reproductive health
An imbalanced gut microbiome (a condition known as dysbiosis) can lead to chronic inflammation and increased intestinal permeability, often called "leaky gut." When this happens, toxins, bacteria, and undigested food particles can pass through the gut lining and into the bloodstream, triggering immune responses that increase systemic inflammation. Chronic inflammation with roots in gut dysbiosis has been linked to reduced egg reserves and hormonal imbalances.
A 2023 Mendelian randomization study in Frontiers in Endocrinology found that gut microbiota imbalances may influence endocrine disorders, such as PCOS and endometriosis, which are two of the most common causes of infertility.
Common signs of dysbiosis or leaky gut may include:
- Bloating, gas, or irregular bowel movements
- Food sensitivities or intolerances
- Brain fog or difficulty concentrating
- Fatigue or low energy levels
- Acne, eczema, or other skin issues
- Hormonal imbalances (which can sometimes appear as irregular periods, PMS, or low libido)
- Sugar cravings or blood sugar fluctuations
- Frequent illness or low immune resilience
Dysbiosis can be triggered by a variety of factors including chronic stress, poor diet, infections, environmental toxins, medications like birth control or antacids, and especially antibiotics, which can wipe out both harmful and beneficial bacteria.
Nutrient absorption and fertility
Even if you're eating a nutrient-rich diet, a compromised gut may not effectively absorb key vitamins and minerals necessary for reproductive health. This is often due to damage to the intestinal lining, imbalanced gut bacteria, and chronic inflammation, all of which can interfere with the body’s ability to break down food, activate nutrients, and transport them into the bloodstream. Nutrients like folate, iron, zinc, selenium, and B vitamins support egg and sperm health, hormone synthesis, and early fetal development.
Improving gut integrity helps ensure that the body can absorb and utilize these critical nutrients. This is especially important before pregnancy, when building up nutrient reserves can buffer against nausea, food aversions, or reduced appetite in the first trimester.
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The Gut-Hormone Axis
The gut communicates with the endocrine system through what scientists call the "gut-hormone axis." Certain gut bacteria influence the regulation of key reproductive and metabolic hormones, including estrogen, progesterone, insulin, and cortisol, which are hormones that affect ovulation, menstrual regularity, and the ability to conceive.
For instance, dysbiosis can disrupt estrogen metabolism through the estrobolome, a group of bacteria responsible for breaking down estrogen and recycling estrogen. When this system is impaired, it can lead to hormonal imbalance associated with PMS, fibroids, endometriosis, irregular cycles, and infertility.
Additionally, poor gut health can influence insulin resistance, which plays a central role in conditions like PCOS (polycystic ovary syndrome). Imbalanced gut bacteria may also increase cortisol (the stress hormone), which can suppress ovulation and disrupt the delicate balance of the hypothalamic-pituitary-gonadal (HPG) axis. Low microbial diversity has even been linked to disruptions in progesterone levels, which are essential for sustaining a pregnancy.
As a functional nutritionist, in practice, I frequently see that when the gut is out of balance, it can send ripple effects across the entire hormonal ecosystem, making it harder to conceive and maintain a healthy pregnancy. But there are steps to take to bring the gut microbiome back into balance.
5 evidence-based ways to support gut health for fertility
1. Eat a diverse diet rich in fiber
Focus on vegetables, fruits, legumes, whole grains, and fermented foods to feed beneficial bacteria.
2. Reduce ultra-processed foods and added sugars
These feed inflammatory microbes and contribute to dysbiosis.
3. Take steps to manage stress
Chronic stress disrupts gut bacteria and increases intestinal permeability. Incorporate mindfulness, sleep hygiene, and movement.
4. Support your oral and vaginal microbiomes
Oral health impacts digestion, and the vaginal microbiome plays a role in conception, too.
5. Prioritize high-quality, bioavailable nutrients
Look for prenatal supplements designed to be gentle on the gut and easy to absorb.
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Egg Quality +
A note from WeNatal on gut health and fertility
At WeNatal, we believe that a healthy life, and a healthy pregnancy, starts in the gut. That’s why our nutrition-first approach to fertility supports the gut at every stage of the journey. Our prenatal supplements are designed with bioavailable nutrients that work with your digestive system, not against it, so your body can absorb what it truly needs.
When you're preparing to conceive, caring for your gut microbiome is one of the most powerful ways to support hormonal harmony, nutrient resilience, and lifelong wellness for both you and your baby.
RELATED: Your fertility meal plan: A week of healthy, easy recipes
References
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