When we think of the body’s microbiome, we tend to first think of the digestive system. While the thousands of bacterial species in the gut are the most well-studied, it’s important to remember that micro-organisms inhabit most of the body’s surfaces. These bacteria form a natural, symbiotic relationship with our health. When the microbiome is in balance, it plays a crucial role in supporting the immune system, digestion, nutrient absorption, skin health, brain function, respiratory health, keeping our levels of inflammation low, and much, much more. .
Microbiome and Reproductive Health
Did you know that around 9% of a woman’s microbiome is found in the reproductive tract? This microbiome extends from the external labia through the vagina to the endometrium (the lining of the uterus) and has a big influence on reproductive health and fertility.
In a healthy reproductive microbiome, the Lactobacillus species—particularly Lactobacillus crispatus, Lactobacillus jensenii, Lactobacillus inert, and Lactobacillus gasseri—are dominant. These beneficial bacteria help create an acidic environment in the endometrium, producing lactic acid and other compounds that:
- Reduce inflammation
- Promote embryonic implantation and growth
- Support sperm health
- Inhibit the growth of harmful pathogens.
Research shows that a balanced reproductive microbiome can be linked to improved pregnancy outcomes – importantly, a reduced risk of preeclampsia and miscarriage.
In contrast, when there is an overgrowth of pathogenic bacteria (both in the digestive and the reproductive tracts), there tends to be a higher level of inflammation and infection in the endometrium. This can lead to problems with embryo implantation, placental function, and thus an increased risk of miscarriage. There’s even evidence suggesting a connection between pathogenic bacteria in the endometrial microbiome and conditions such as endometriosis.
Interestingly, the gut microbiome plays a key role in influencing the microbiomes of other organs, including the reproductive system. The short chain fatty acids (SCFAs) like butyrate, propionate, and acetate, produced by the beneficial gut microbiome, have been shown to regulate reproductive hormones such as LH and FSH and influence systemic inflammatory levels.
Microbiome Changes During Pregnancy
Your microbiome undergoes changes throughout pregnancy. In the first trimester, microbiome diversity increases, while in the second trimester it becomes more simplified. By the third trimester, the Bifidobacteria species becomes dominant in the digestive system, possibly in preparation for labour and the transfer of beneficial bacteria to the newborn, helping to establish their own healthy gut microbiome.
Microbiome in Men’s Reproductive Health
In men, the semen microbiome plays an important role in reproductive health. Studies have shown that beneficial bacteria, such as Lactobacillus and Bifidobacteria species, can improve sperm quality and reproductive outcomes by supporting an anti-inflammatory environment and reducing oxidative stress.
On the other hand, an overgrowth of pathogenic bacteria, (such as E coli), in the semen can impair sperm motility and morphology, decreasing the chances of successful fertilisation.
Practical Steps to Support Your Microbiome
Your diet and lifestyle are some of the most impactful tools for promoting a healthy microbiome throughout the body. Here are some tips to support your microbiome and, by extension, your reproductive health.
- Eat a variety of colourful vegetables to provide food (such as a group of compounds called polyphenols) for the beneficial bacteria.
- Choose healthy fats such as those from fish, eggs, avocado, nuts, seeds, and olive oil instead of fried or processed foods or vegetable oil.
- Incorporate legumes and beans such as peas, lentils, and chickpeas into the diet at least 1-2 times per week. These contain fibre that the good bacteria feed on.
- Stay hydrated by drinking 2-2.5 litres of water per day.
- Stop smoking, as this negatively impacts the microbiome.
Additionally, your naturopath or acupuncturist at The Fertility Pod may recommend specific probiotics to support reproductive health. There are various strains of probiotics and selecting the right one can positively influence the microbiome throughout your body. In some cases, intravaginal probiotics (applied topically) can provide a targeted, multi-directional approach.
While probiotics can be important, prebiotics (the food that beneficial bacteria feed on), are equally essential. The dietary tips above give some ideas of how to feed the microbiome and supplements like PHGG, lactulose, and lactoferrin can also provide extra food for the beneficial bacteria.
Functional Testing and Personalised Care
To further personalise your care, your naturopath can arrange functional testing to assess the health of your digestive or reproductive microbiome. This testing can help identify imbalances and guide the use of specific supplements, herbs, and probiotics for you.
At The Fertility Pod, we understand that the entire body is interconnected, and this is why we focus on whole-body-health, to improve reproductive health and fertility.
References:
- Di Simone Nicoletta et al, “Recent Insights on the Maternal Microbiota: Impact on Pregnancy Outcomes”, Frontiers in Immunology, Volume 11, 2020, ISSN:1664-3224
- European Fertility Society, ”The Role of Microbiome in Human Implantation” June 7, 2024, https://www.europeanfertilitysociety.com/the-role-of-the-microbiome-in-human-implantation-lv/
- European Fertility Society, ”Fertility and the Microbiome” June 7, 2024, https://www.europeanfertilitysociety.com/fertility-and-the-microbiome-lv/
- Rhiannon Hardingham “Pregnancy Masterclass” 2024
