Oestrogen Dominance and PCOS: What It Is & What To Do About It

How much do you really know about the hormones in your body?

The reality is that we don’t know as enough as we should.

Chances are good if you have had Polycystic Ovary Syndrome for a while, you’ve heard about oestrogen dominance

But do you know what it is and why it’s important?

This article focuses on female sex hormones, oestrogen dominance, and what you need to know.

Female sex hormones

Hormones are chemical messengers produced by the endocrine glands to serve a number of purposes. Your health and wellbeing depends on the balance of more than 50 hormones that are secreted and circulate around the body.

Men and women both have sex hormones such as testosterone and oestrogen…

Female sex hormones include oestrogen and progesterone, and our bodies also produce a small amount of testosterone…

But in PCOS, women usually have more testosterone (often thought of as a ‘male hormone’) than they should. In fact, it is part of the diagnostic criteria.

Saying that, testosterone is necessary for the production of oestrogen through an enzyme called aromatase. (1)

The ovaries and placenta mainly produce oestrogen, but our adrenal glands also secrete small amounts. In a female body, oestrogen effects the mammary glands, vagina, fallopian tubes, and uterus, to name just a few.

The oestrogen family includes different hormones such as:

  • Oestrone – a weak type of oestrogen; the major type found in postmenopausal women
  • Oestradiol – the strongest type of oestrogen; produced by the ovaries
  • Oestriol – the weakest form of oestrogen; a waste product made after the body uses estradiol

Besides having a role in sexual and reproductive health and features in women, oestrogen also takes part in thickness and quality of your skin, bone strength, liver and heart functions, amongst other actions.

Progesterone is yet another important hormone in a female body. This particular hormone is secreted by your reproductive system to regulate the condition of the endometrium (inner lining) in the uterus. While the ovaries, placenta, and adrenal glands produce progesterone, the main source is the corpus luteum.

As the egg is released, the corpus luteum gland is formed, which produces progesterone. You need both these hormones to act in a balanced way to be well and to become a Mum. (2)

We don’t have the same level of these hormones all the time. It’s natural for oestrogen and progesterone to fluctuate, go up and down, throughout the menstrual cycle, but sometimes these changes can be too drastic and lead to potentially dangerous complications.

One of these complications is oestrogen dominance.

What is oestrogen dominance?

Oestrogen dominance (ED) is a unique condition indicated by deficient, normal, or high levels of oestrogen but little to no progesterone. While many of us assume oestrogen dominance is all about this particular hormone, the problem is associated with progesterone too.

The term oestrogen dominance was coined by doctor John R. Lee, and Virginia Hopkins, both of whom authored a book called What Your Doctor May Not Tell You about Menopause: The Breakthrough Book on Natural Progesterone. In Dr. Lee’s book, he talks about the dangers of conventional therapies used for combating symptoms of menopause, focuses on alternative ways of encouraging healthy hormone regulation, and explains how progesterone levels influence the concentration of oestrogen and that depletion of this hormone can lead to ED.

Despite the fact that hormone challenges are common, the idea of oestrogen dominance is not widely accepted in mainstream medicine. Yet it’s an important topic, because…

When left unresolved, oestrogen dominance could increase breast cancer risk, lead to thyroid-related problems, increase heart disease risk, and cause many other complications and unpleasant effects.

Why does oestrogen dominance occur?

As discussed, oestrogen dominance can happen when oestrogen is too high, but it also occurs when levels of this hormone are normal if progesterone is decreased. When this problem arises, multiple factors play a role.

In some cases, high oestrogen levels can develop naturally, but it can also be a result of medications and therapies. For instance, the oestrogen replacement therapy that is prescribed to some menopausal women can lead to problematic oestrogen levels which also increase the risk of breast cancer. (3)

Other causes can contribute to oestrogen dominance due to their endocrine disrupting effects, and important ones are listed below:

Polycystic Ovary Syndrome (PCOS)

Of course, given that I’m writing on Conquer Your PCOS Naturally, and I live and breath this syndrome… I’m a little biased.

Polycystic Ovary Syndrome is a complicated and common condition indicated by the presence of small cysts on one or both ovaries, menstrual irregularities, and/or increased androgen levels (4).

The latest figures show that 8% to 20% of women of reproductive age around the globe have PCOS. Although the exact prevalence of the condition in American women is unknown, estimates reveal it affects about 5 million girls and women of reproductive age. While most women are diagnosed with this condition in their 20s and 30s, it can also occur in girls as young as 11 (5). These stats are not dissimilar in my home country of Australia, my husband’s native England, or other developed countries around the world.

Note: PCOS is the most frequent culprit for anovulatory infertility, and it tends to go hand in hand with oestrogen dominance.


Stress is a physical response to a perceived threat. Our body thinks it is under attack and launches into “fight or flight” mode to deal with the potential danger. Stress disturbs production and the concentration of hormones, including sex hormones and insulin, thus creating a domino effect.

While we can’t really avoid stress entirely, we can manage stress better. When left unresolved, stress can cause many problems; endocrine disruption is one of them.

Autoimmune disease

Autoimmune diseases occur when the immune system attacks healthy tissues and organs in the body. The National Institutes of Health (NIH) report 23.5 million Americans have some form of autoimmune disease, but the American Autoimmune Related Diseases Association claims that 50 million people in the US are affected by these conditions. The difference in estimates occurs because the NIH only takes into account 24 autoimmune conditions, but there are 80-100 in reality. (6)

In some autoimmune conditions oestrogen enhances autoimmunity. (7) This confirms the relationship between autoimmune diseases and oestrogen increase and may also explain why women are more likely to get diagnosed with these conditions.

Environmental oestrogen’s

Our environment plays a huge role in our hormone regulation. We come into contact with harmful chemicals, toxins, and xenoestrogens on a daily basis.

Note: Xenoestrogens are manmade or synthetic chemicals which mimic the action of oestrogen (8) In the body. The buildup of these chemicals can raise oestrogen levels and cause dominance.

Other causes

  • Personal care products containing parabens, phthalates, and other similar compounds
  • Imbalance of gut microbiota
  • Excess body fat
  • Birth control and hormone replacement therapy (HRT)

Signs and symptoms of oestrogen dominance

When oestrogen levels rise and fall through a normal menstrual cycle, your body experiences a wide array of symptoms. For women with PCOS, an irregular — or absent — cycle can signal signs and symptoms as well.

Although the experience of oestrogen dominance can vary in intensity from one woman to another, common challenges include:

  • Acne
  • Anxiety
  • Bloating
  • Changes to bowel movements
  • Cold hands or feet
  • Difficulty getting enough sleep
  • Fatigue and/or sleepiness
  • Fertility problems
  • Fibrocystic lumps in breasts
  • Hair loss
  • Headaches
  • Increased premenstrual syndrome (PMS) symptoms
  • Irregular or abnormal menstrual periods
  • Low sex drive
  • Memory problems
  • Mood swings
  • Other hormonal imbalances e.g. thyroid hormones
  • Slowed metabolism
  • Tenderness and swelling in the breasts
  • Water retention
  • Weight gain

INTERESTING FACT: High oestrogen and low progesterone are associated with increased assertiveness in women. (9)

Managing oestrogen dominance

When left unmanaged, oestrogen dominance can cause a myriad of problems. Fortunately, there’s much you can do to restore hormonal balance and avoid potential complications.

It is important to schedule an appointment with a health professional who understand ED, whether an integrative doctor, a naturopath or other suitably qualified practitioner, if you experience the signs and symptoms mentioned above. Don’t wait for them to go away on their own (chances are, they won’t).

Prior to making a diagnosis, blood or saliva tests will assess the relevant hormone levels in your body. These tests will reveal whether oestrogen levels are normal or high, and will usually focuses on oestradiol and oestrone levels.

Oestrogen levels are measured in picograms per millilitre (pg/ml). According to the Mayo Clinic Laboratories normal levels of oestrone in premenopausal women is 17-200 pg/ml while the healthy concentration of oestradiol is 15-350 pg/ml. On the other hand, normal levels of oestrone and estradiol in postmenopausal women are 7-40 pg/ml and <10 pg/ml respectively. (10)

Once diagnosed, the choice of treatment depends on the severity of oestrogen dominance and what path you wish to follow.

In order to restore oestrogen balance and prevent potential complications, lifestyle changes are key. These include:

Modifying your food plan

The foods we eat directly and indirectly influence the levels of various hormones in our bodies.


We need to talk about phytoestrogens, or the plant-derived compounds found in many foods that act as weak oestrogens.

There is much debate around these compounds. Some people assert that phytoestrogen rich foods, particularly soy, are the oestrogenic devil, while others claim it has far reaching benefits.

Where’s the truth?

We’re yet to know definitively, but I suspect the truth lies somewhere in the middle.


As the weaker phytoestrogens match the cell’s oestrogen receptors, they block the more potent form of this hormone, leading to a reduced active oestrogen load.

Add fibre

When making dietary adjustments to fight oestrogen dominance, you need to consider eating fibre-rich foods. A growing body of evidence confirms that fibre aids weight loss (11) and maintenance. As overweight and obesity are common risk factors for oestrogen dominance, losing excess kilos could help you kick-start oestrogen balance.

To enable your hormones to function well, also avoid junk food, sweets, and other foods with little to no nutritional value.

Sugar is a negative game changer for all things PCOS.


Exercise is a vital key to your health and wellbeing.

Regular physical activity is essential for weight management… (12) And you already know how significant a healthy weight is for hormone balance.

It can also reduce stress and enhance insulin sensitivity, both key in a happy hormonal balance.

What’s more, one study found that exercise can lower oestrogen and decrease breast cancer risk in women from the high-risk group. (13)

Improve liver function

The liver is a huge organ that performs various important tasks that keep you healthy. The primary function of this organ is filtering blood that comes from the digestive tract before proceeding to the rest of the body.

Yet another significant function of the liver is detoxification. This organ eliminates toxins and wastes that would, otherwise, accumulate in your body and disrupt hormone balance, increase the risk of disease, and cause other problems.

Improving liver function is, therefore, an effective strategy to manage oestrogen balance. To keep your liver healthy, you need to limit or avoid alcohol consumption, eat anti-inflammatory foods, manage stress, exercise regularly, and drink sufficient pure water.

Improve digestion

The main function of the gastrointestinal tract is to break down food and absorb the nutrients required to maintain a body healthy. At the same time, the digestive tract eliminates toxic and other harmful substances.

Even though we tend to associate gastrointestinal tract with food digestion, it is also important for hormonal balance. Imbalances of oestrogen and progesterone can influence the movement of food through the intestines and cause problems such as bloating, diarrhoea, and constipation.

Bearing in mind that digestive problems contribute to a reduced disposal of oestrogen from the body, you also need to take care of your digestion. The high-fibre food plan mentioned above can be of enormous help.

Plus, in our article The 16 Point CheckList For A Better PCOS Gut you’ll discover sixteen ways to improve your digestive function.

Other things to do

  • Avoid plastic containers and bottles containing BPA and BPS as these are endocrine disruptors
  • Drink sufficient water
  • Use appropriate essential oils
  • Consult your health professional about supplements to support you and possible nutritional deficiencies to combat
  • Get enough sleep


Oestrogen dominance is a serious problem with the tremendous potential to affect our health and quality of life. Causes of this problem are numerous, but so are the options to manage it.

With a proactive attitude and the right approaches, it is possible to balance oestrogen and progesterone levels and improve your health and wellbeing.

From PCOS to perfect health, with love,

Dr Rebecca Harwin







Dr. Rebecca Harwin
The PCOS Expert
Chiropractor & Bestselling Author

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One Response to Oestrogen Dominance and PCOS: What It Is & What To Do About It

  1. Rakshita Agrawal May 8, 2018 at 8:28 am #

    Interesting information provided related to pcos and what one should do about it. Thanks for sharing the blog with us.

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