FertilityFor ProfessionalsGut Health

The Gut-Fertility Connection

By March 1, 2021April 7th, 2021No Comments

How is gut health connected to fertility?

One of the unsung heroes in the miracle that is the human body, your gut does much more than merely digest, absorb and excrete food. It’s responsible for the proper function of your immune system, how you think and feels, how you synthesize and excrete hormones. Oh, and it influences your fertility too.

Quite simply, when your gut— which influences the health of everything in the body— isn’t functioning at its optimal level, it has a knock-on effect on other body systems, including fertility.

When it comes to fertility (in both women and men), your gut microbiome can make a significant difference. Indeed, new research has shown how poor gut health can cause an estrogen imbalance, which may lead to infertility issues ranging from endometriosis and polycystic ovary syndrome to testicular dysfunction.

Research on the gut-fertility connection…

It might sound hard to believe, but gut health and fertility are inextricably linked. And that’s why couples looking to conceive should always focus their attention on optimising their gut health.A growing body of evidence has confirmed the gut-fertility connection and its importance for our wellbeing. This include the following:

  • Women with recurrent pregnancy loss were found to have abnormal gut permeability (aka leaky gut), which has been shown to contribute to inflammatory reactions in the body[1]. The researchers hypothesised that the inflammatory reaction caused by leaky gut may be contributing to miscarriage pathogenesis.
  • The gut microbiome is responsible for converting bound estrogen to free, active estrogen via the enzyme B-glucuronidase. According to a recent review, without a healthy microbiome, estrogen metabolism and function becomes impaired and can lead to a number of health consequences including endometriosis, PCOS, endometrial hyperplasia and infertility. Authors of this review concluded that treating the gut microbiome to modulate estrogen levels should be considered as a new future treatment for estrogen-mediated diseases including infertility[2].
  • A meta-analysis (a statistical analysis that combines the results of multiple scientific studies) completed in 2016 found that women with unexplained infertility have x 3.5 higher odds of having Celiac Disease[3]. Furthermore, it has been estimated that as much as 6% of women struggling with unexplained infertility actually have undiagnosed Celiac Disease[4].
  • Gut health, specifically the gut microbiome, plays a vital role in immune function. When our immune system isn’t working optimally due to poor gut health, our bodies may enter a state of chronic inflammation. This, in turn, can result in recurrent pregnancy loss. Chronic inflammation may also cause decreased progesterone levels leading to implantation failure[5], the development of autoimmune processes impacting fertility[6], and the development of anti-sperm antibodies preventing fertilisation. Thankfully, probiotic supplementation to support gut health has been shown to decrease chronic inflammation and improve immune function[7].

The importance of estrogen for fertility…

Estrogen has always been considered a female dominant hormone for reproductive health, but this hormone actually pays a key role in fertility in both men and women.

For women, estrogen is needed for proper ovulation and thickening of the uterine wall for pregnancy. It’s important that estrogen levels are neither too high nor too low, though.

Excess estrogen, for instance, may cause irregular periods and can prevent ovulating, thereby resulting in infertility. Estrogen dominance has also been linked to infertility issues in women such as endometriosis and polycystic ovary syndrome.

Estrogen deficiency, meanwhile, can also cause amenorrhea (an abnormal absence of menstruation), which leads to anovulation. Disorders of ovulation account for approximately 30% of female infertility and present mainly with irregular periods or amenorrhea.

The importance of estrogen for men’s sexual health is equally significant, impacting on multiple organs and tissue by affecting their reproductive system in a number of ways.

A deficit or surplus of estrogen can, for example, hinder the male libido (sex drive), with obvious implications for fertility. Meanwhile, spermatogenesis, an inappropriate increase in estradiol (an estrogen steroid hormone) has been shown to lead to a decrease in sperm production; while too little estrogen has been shown to have a causative effect with erectile dysfunction.

A balancing act

Hormones in your body are always in a careful balancing act. If one of your organs is not functioning properly, everything is thrown off-balance.

 Your gut, the ‘forgotten organ’ or ‘second brain’ is a key regulator in circulating and eliminating estrogen, which is why it’s so important to focus on gut health when it comes to fertility.


[1] https://www.ncbi.nlm.nih.gov/pubmed/?term=recurrent+pregnancy+loss+leaky+gut
[2] https://www.ncbi.nlm.nih.gov/pubmed/28778332
[3] https://www.ncbi.nlm.nih.gov/pubmed/25564410
[4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4216449/
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4137456/
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4845518/
[7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2701523/

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Amy Martin

Marketing Director

Amy is a high achieving individual with a number of marketing awards under her belt, including Young Digital Business Person of the Year 2019. She is a big believer in digital marketing and an expert in executing personalised targeted campaigns. Amy strives to learn from data and campaigns that show return on investment.

Robert Gordon

Managing Director, Gordons Chemists


Robert Gordon, director at Gordons Chemist's. Gordons Chemists is a chain of more than 60 pharmacies, located in NI and Scotland. Gordons Chemists is Northern Ireland's largest independent pharmacy chain.

Dr. Debbie Collins



Dr. Debbie Collins MBBchBAO MRCGP, a practicing GP and partner in Belfast. She has a passion for patient education and advocacy. Her special interests are Women's Health and Fertility

Sarah Trimble

Nutritional Therapist


Sarah Trimble - a nutritional therapist with a passion for good food instead of fad diets. Sarah has a particular Interest in using the power of nutrition to support hormonal imbalances and reproductive health.

Barbara Scott

Director, Seren Natural Fertility
Chair, Association of Reproductive Reflexologists


Barbara Scott is Chair of The Association of Reproductive Reflexologists, founder of Seren Natural Fertility and author of Reflexology for Fertility. In 2017, she was awarded ‘Complementary Therapist of the Year’ by the Federation of Holistic Therapists and has been nominated for several awards within the field of complementary therapy. In 2019 she was awarded the Innovation in Reflexology Award by the Association of Reflexologists.

Barbara speaks and lectures globally on her integrative approach to supporting couples having difficulties conceiving. She has spoken at many of the Fertility Shows and Fertility Fest. Alongside her own busy clinics, she also trains practitioners in providing this integrative, approach to fertility and reproductive healthcare and well-being. The ARR (Association of Reproductive Reflexologists) has trained practitioners globally, from Australia, New Zealand, Canada, Europe, and most areas of the UK.

Her expertise and passion is in advocating a patient-centred and integrative approach to supporting both men and women on their journey to parenthood.

Cindy Charles

Fertility coach and Founder of Fertilelife


Cindy Charles- Fertility coach and Founder of Fertilelife. Cindy is a committed advocate of social and personal development. Her own life experiences inspired her fertility support services. Cindy has worked with the Fertility Network UK, and has had the privilege to work as a resident Fertility Coach for the London Women's Clinic on Harley Street. Cindy believes in the importance of nurturing our own fertility.

Dr. Lyuda Shkrobot

MD, MSc Gynecologist, Fertility specialist at unq.life fertility clinic


Dr Lyuda has a special interest in reproductive immunology. Dr Shkrobot assisted in establishing the first European Donor Egg programme at Sims, coordinating and liaising with Intersono Clinic in Ukraine Advisors. She is passionate about patient-centred, results-driven care.

Lisa Corcoran

Business Development Executive


Lisa has 15 years of commercial business experience. She has proven her capabilities in Investment Property Sales and, Management & Business Development for Technology companies that have provided her with an understanding of different customer needs across several sectors. Lisa appreciates the value of customer education and relationship building in long-lasting partnerships.

Aoibheann Murphy

Chief Financial Officer


Having trained with PWC, Aoibheann qualified as a Chartered Accountant in 1997. She subsequently spent eight years working in industry, gaining invaluable experience in many areas In 2005 Aoibheann became MD of Pangur Consulting, providing professional expertise to a broad client base. She is looking forward to the new challenge of Nua Fertility.

Share a little about yourself—the things we wouldn’t learn from simply reading your professional bio.


What was your journey to parenthood like?

Right craic!

Do you prefer podcasts or books? And of the one that you prefer, what is a show or title that you recommend?

I love sport…any sport…and the outdoors. Living in the Barrow valley I get to enjoy swimming and kayaking in the Barrow and exploring the Blackstairs mountains. Since I hung up my soccer boots (the body just couldn’t take it anymore!), I’ve been cycling with my lovely friends in Mount Leinster Wheelers and was chuffed to have completed the Ironman 70.3 triathlon event in Dublin in 2019!
I’m an avid reader…books beat podcasts hands down!...although recently I’ve dabbled with audio books through the library app Borrow Box. “A Little Life” left its mark on me. A harrowing story, definitely not for the faint hearted.

If there was just one thing you could impart on women on their journey to parenthood, what would it be?

Don’t be consumed by the roles in your life – parent, partner, employee etc. Parenthood, be it getting there or going through it, will have its tough times. Cherishing yourself as an individual and making time for yourself can help you through those times….it’s good to be a bit selfish!!

Mark Mullins

Director of Sales


What was your journey to parenthood like?

To be honest it was very difficult. At the beginning we thought that when we decided that we wanted to start a family Deborah would fall pregnant shortly afterwards like many of her friends. As time went by, we started to suspect something was wrong. After initial tests we found out that I had a low sperm count which meant that we would have to go down the assisted pregnancy route. This took me several months to get my head around as I blamed myself for this. All I wanted was my wife to be able to go through the pregnancy journey. We couldn’t wait to become parents. There were many long and painful nights where I thought this would never happen for us. After several failed attempts we decided to look at further ways of improving our chances. This led us to look at fertility supplements, our diet, exercise. I will never forget when that morning during our Two Week Wait when Deborah woke me up at 5 a.m. to show me those two lines, we had both been yearning for! We are blessed to now have our beautiful daughter.

On challenging days, what kept you going? Where did you find inspiration?

My wife was my inspiration. She kept me going through those challenging months and years. She was there to help me deal with everything. The guilt I felt when I saw her having to go through everything.

What is your ideal was to relax and unwind?

My latest passion is cooking on my BBQ. I find it so peaceful and I just switch off. It just gives me a bit of alone time which everyone needs.

If there was just one thing you could impart on men as they begin trying to become parents, what would it be?

I would highly recommend communicating with friends and family. A problem shared is a problem halved. Failing that there are some really good private Facebook groups for men suffering from infertility. I found this great support through the good and especially the bad times.

Deborah Brock

Founder & CEO of Nua Fertility


Deborah has a personal passion for fertility health, supporting people and communities. With over 15 years experience of working in the Non profit and Education sector, I have had the honour of working together with people and communities focusing on their strengths, capacities and assets. With extensive senior management, project management and creative programme development experience.

How did your experience with fertility inspire you to help start Nua Fertility?

My own personal fertility journey opened my eyes to the world of fertility health. Trying for a baby is one of the most exciting yet vulnerable times in your life. It took myself and my husband over three years and the helping hand of science to become a mum.  I have always worked with people and communities and felt my vision for Nua Fertility could genuinely support others who have fertility challenges.

Share a little about yourself—the things we wouldn’t learn from simply reading your professional bio.

I'm am curious person and love all things research. My ideal evening would be reading and exploring scientific journals! I like to think I am a little bit creative and I LOVE paint by numbers! Its probably the only time I slow down, I become immersed in the painting and think of nothing else.

What do you want to tell someone trying to conceive or already pregnant?

Educate yourself! Knowledge is power. The more you inform yourself about your fertility health the more you are empowering yourself with knowledge. Own your journey and take control over your own fertility health.

What’s something you wish someone told you while trying to conceive?

Open up and talk with friends and family. I was surrounded by amazing friends and family but I never opened up. When your struggling to conceive, a non-judgemental ear to listen or a shoulder to cry on is so powerful.