Could Your Irritable Bowel Be Linked to Your PCOS?

By Clare Goodwin

Last updated: September 3, 2020

Do you have PCOS and IBS (irritable bowel syndrome) symptoms? You might be surprised to know you’re not alone and that this isn’t an unfortunate co-incidence. A 2009 study found that an astonishing 42% of women with PCOS also had IBS. Only 10% of women without PCOS have IBS. Even more interesting was that the women with both PCOS and IBS also had significantly more weight gain than those with PCOS alone (1). There’s definitely a relationship between PCOS and IBS, which this article will explore.

What is Irritable Bowel Syndrome (IBS)?

IBS is one of those somewhat annoying diagnoses. It’s often diagnosed when all other disease conditions, such as coeliac disease, inflammatory bowel disease and Crohn’s disease, have been ruled out.

IBS is defined by the Rome Criteria as having abdominal pain for at least 3 days a month, for the last 3 months, as having abdominal pain lasting at least 3 days a month, for at least 3 months, in association with two of more of the following symptoms (2):

  • Pain that improves with defecation.
  • Change in stool frequency.
  • Change in stool consistency.

If you meet these criteria then you’ll probably be told there isn’t much that can be done for you. Alternatively, you may be prescribed anti-diarrhoea, anticholingeric, or antispasmodic medications, or laxatives for constipation. Anticholinergic and antispasmodic drugs are used to reduce bowel spasms and pain, but unfortunately they can actually exacerbate the root cause of IBS.

If you’d like to find out how to reduce your IBS symptoms then click below to get my free download – 2 Steps to Reduce Inflammation and IBS:

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What is the Root Cause of Irritable Bowel Syndrome (IBS)?

PCOS and IBS are similar in that IBS is not a single disease with a single cause. Rather, it’s a syndrome — a collection of signs and symptoms — that has multiple possible causes. If you’ve read my article, What’s Contributing to Your PCOS and Why You Need to Know, then you’ll know that PCOS can be caused by many factors.

Similarly, IBS is very individual. Generally, it involves changes to the gut bacteria or structural changes in the GI tract. Here are the main causes that I see in patients:

Small Intestinal Bacterial Overgrowth (SIBO)

Your gut bacteria should only reside in your large intestine. Small Intestinal Bacterial Overgrowth (SIBO) occurs when gut bacteria moves up into the small intestine, causing major issues. One study of over 200 patients with IBS showed that a staggering 84% of them had SIBO (3).


Your gut hosts 100 trillion microorganisms, which are responsible for a range of things. These microorganisms make up 70% of your immune system and control how many calories, carbs, and nutrients your body absorbs from food. Disruption in the amount of beneficial vs harmful bacteria is called gut ‘dysbiosis’.

Studies have shown that up to 73% of IBS patients have intestinal dysbiosis, i.e. not enough good bacteria or an overgrowth of bad bacteria, fungus or yeast (4).

Leaky Gut or Intestinal Permeability

One of the functions of your gut is to absorb nutrients that your body needs, whilst keeping foreign objects out. The wall of your gut is made up of cells that are very tightly packed together and only let some objects through. However, these cells can spread apart and make your gut ‘leaky’ to larger molecules. Research has shown that IBS patients are very likely to have ‘leaky gut’ (5).

How Could IBS be linked to PCOS?

As I explained before, the are many causes of IBS. Each of these causes can play a part in the development of PCOS. However, too keep it simple I’ll just explain one: intestinal dysbiosis (and how that can lead to leaky gut).

Too little ‘good’ bacteria or too much ‘bad’ bacteria in the gut not only causes IBS symptoms, but also causes systemic inflammation (6) and insulin resistance (7). Systemic inflammation and insulin resistance both increase ‘male’ hormone (androgen) levels. This increase in ‘male’ hormones is really the crux of PCOS. Increased androgens disrupt the normal menstrual cycle, preventing ovulation and also causing facial/body hair growth, acne and hair thinning.

Here’s how researchers propose this works:

Your gut wall is formed of tightly packed cells. These cells allow essential nutrients to go through and nourish the body, but also keep out the large molecules which cause inflammation and immune activation.

Too much bad bacteria causes the release of a substrate called Zonulin, which causes gaps between the normally tightly packed cells in your gut. This is known as ‘leaky gut’ or intestinal permeability. Leaky gut allows large molecules, like gluten and Lipopolysachharide (LPS) from bad bacteria, to pass from the gut into the body. This causes immune system activation and inflammation.

Inflammation that isn’t turned off (chronic inflammation) can interfere with your insulin receptors and cause insulin resistance. This results in high levels of insulin that acts on the ovaries and causes them to overproduce testosterone. Excess testosterone causes a disruption in the hormones involved in the menstrual cycle, preventing ovulation. When you don’t ovulate, the follicles that house the eggs stay ‘stuck’ on the ovary. This is what PCOS ‘cysts’ are.

In my article, “Is Your Gut Bacteria the Secret to Your PCOS Weight Loss”, I explained that too much bad bacteria causes you to absorb more calories and carbohydrates from your food. This could be part of the reason why women with PCOS suffer from weight gain, even on a low calorie diet.

The most important thing to do is to treat the root cause of your IBS.

What Should I Do If I Have PCOS and IBS?

Find the root cause of your IBS! Although there can be many causes of IBS, the ones that I focus on are SIBO and intestinal dysbiosis. Here’s how you find out if you have those:

Get Your Gut (i.e. Poo) Tested

For many people, healing your gut is not quite as simple as cleaning up your diet and taking probiotics. If you have an overgrowth of bad bacteria, yeast (i.e. candida) or parasites, then you’ll need to go through a ‘killing phase’ to eradicate it.

Imagine that you have a garden that’s completely overgrown with weeds. It wouldn’t matter how many roses you planted in there, they wouldn’t thrive if it was overgrown with weeds. You would need to remove the weeds first. It’s exactly the same with your gut bacteria. However, you can’t look inside your gut like you could look at a garden. The only way you’ll know what’s in your gut is by having a comprehensive stool analysis done.

This process involves sending off a frozen faeces sample and having it tested for levels of good and bad bacteria, as well as yeast, fungus and parasites. This is not available through conventional medical providers, as conventional medicine tends to only treat symptoms, not identify root causes of illness. Therefore, if you have IBS then you should work with a functional medicine practitioner and get a comprehensive stool analysis done. This will help to inform you of whether you need to go through an eradication process.

Get a SIBO Breath Test

When bacteria move into the small intestine they release gases (methane and hydrogen) when you consume sugar. This comes out in your breath in a certain pattern which can indicate SIBO. Some specialist hospitals have started to offer this testing, so ask around. Alternatively, seek out a functional medicine practitioner who can help you get this done privately.

If SIBO is present then you cannot just ‘starve it out’. Instead, you’ll need to go through an eradication process. This is a specialist process, so you’ll need to work with someone knowledgeable to help you do this.

What If I Can’t Get Access To These Tests?

You may live in a part of the world where you cannot get access to a Functional Medicine practitioner that can help you with the interpretation of these tests. If you find yourself in this situation then the best thing you can do is to remove inflammatory foods and start to build up the amount of good bacteria in your gut. Although this won’t fix SIBO or bacterial/yeast overgrowth, it will help to reduce inflammation, which can help.

Here’s my free downloadable guide to help you do just that. This includes details of the foods that you shouldn’t be eating, how to increase your good bacteria, and recipes to help heal your gut:

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PCOS and IBS and are similar in that they are not a single disease with a single cause. Rather, IBS is a syndrome —a collection of signs and symptoms — that has multiple possible causes. Many of these causes, such as intestinal dysbiosis, SIBO, and leaky gut, can cause inflammation. This inflammation can lead to a disruption of the female hormones and an overproduction of testosterone. In this way, IBS, is linked to PCOS

If you have PCOS and IBS, don’t just accept it. Work with a functional medicine practitioner to find and treat the root cause.