Could the Microbiome Be a Missing Piece in Unexplained Infertility?

A guest blog post: Anna Worgan Darrock BA (Hons)

Could the Microbiome Be a Missing Piece in Unexplained Infertility?

Being told your fertility struggles are “unexplained” can feel incredibly frustrating.

But one area researchers are increasingly paying attention to is something many people have never heard about- the reproductive microbiome.

The microbiome is the community of bacteria that live throughout our bodies. When balanced, these microbes help regulate inflammation, hormones, immunity and tissue health- all of which play a role in fertility.

And the reproductive system has its own delicate microbial ecosystem.

Why Vaginal pH Matters

In a healthy vaginal environment, beneficial bacteria called Lactobacillus dominate. They produce lactic acid, which keeps vaginal pH slightly acidic (around 3.5–4.5).

This acidity protects against infections and keeps the reproductive tract stable.

This works when the vagina just needs to protectagainst infection, but when you want to conceive the body needs to adapt- so around ovulation the cervix produces fertile cervical mucus, which helps buffer the acidity and guide sperm toward the egg.

When the microbiome becomes unbalanced and vaginal pH rises above 4.5, inflammation and more harmfulbacteria can increase creating a less supportive environment for sperm and implantation.

Male Microbiome Matters Too

Fertility isn’t just about egg health.

The gut microbiome influences sperm health and the microbiome found in semen. When gut bacteria become disrupted, inflammation and oxidative stress can increase, which can affect:

• sperm motility

• sperm shape

• sperm DNA quality

Because semen enters the female reproductive tract, the male microbiome can also influence the environment sperm enter.

Why This Matters

Fertility isn’t just about eggs and sperm, it’s also about the environment they exist in.

A healthy microbiome helps regulate pH, control inflammation and create the conditions needed for fertilisation and implantation.

For some couples experiencing unexplained infertility, looking at the microbiome in both partners can reveal pieces of the puzzle that are often overlooked.

Interesting fact

Your reproductive microbiome can carry traces of past partners. During intimacy, microbes are exchanged and may influence the vaginal environment long after the moment has passed!

If you’re struggling with unexplained fertility issues, looking at the health of the microbiome in both partners, can sometimes reveal pieces of the puzzle that standard testing may missing.

About

Anna Worgan Darrock BA (Hons), MBAcC is a licensed acupuncturist and qualified medical phlebotomist with a specialist diploma in advanced fertility support.

You can reach Anna on her website

At source acupuncture