Hormone Naturopath & Nutritionist · Australia WideRoot-Cause Support For Women's Hormone Health.

Progesterone drops first

Progesterone is one of the first hormones to drop for most women with hormonal symptoms, and it takes a long time to be identified because the symptoms are so often attributed to stress or ageing.

Progesterone is the calming, steadying hormone.

It is produced by the corpus luteum in the ovary after ovulation, which means it is only made in meaningful amounts in the second half of your cycle, and only if you ovulated that cycle.

Chronic stress, undereating, over-training, nutritional deficiencies (particularly zinc, magnesium, and B vitamins), perimenopause, and certain hormonal contraceptives can all interfere with ovulation, and if ovulation does not happen, no progesterone is produced for that cycle.

Plenty of women are ovulating and still have low progesterone, because a cycle can produce the egg but not produce enough progesterone afterwards, which often comes from stress, poor luteal phase function, or the same nutritional deficiencies that disrupt ovulation in the first place.

Progesterone does a lot of work beyond the reproductive system.

It supports deep sleep by converting in the brain into a neurosteroid called allopregnanolone, which binds to GABA-A receptors, the main calming system in the brain.

When progesterone is adequate, your nervous system has its natural brake on, and you fall asleep faster, stay asleep longer, and wake feeling settled.

When progesterone drops, that calming signal weakens.

Sleep becomes lighter and more fragmented, you start waking through the night (particularly between 2 and 4am), anxiety rises through the second half of your cycle, mood becomes less stable, and irritability and anger feel disproportionate to the situation in front of you.

This is what is happening behind PMS and PMDD.

Progesterone also balances oestrogen through the second half of your cycle.

When progesterone drops, oestrogen is unopposed for longer, which is where heavier bleeds, spotting before your period, breast tenderness, and PMS that takes over 10 or more days of your cycle come from.

I see low progesterone in women in their 20s all the way through to perimenopause, and it is one of the first things I check when the presenting symptoms are anxiety, poor sleep, worsening PMS, and cycles that have shortened.

Oestrogen dominance is about the ratio between oestrogen and progesterone

This is the most common hormonal pattern I see in clinic, and it is one of the most misunderstood.

Oestrogen dominance does not always mean your oestrogen is high. It means your oestrogen is too high relative to your progesterone. Your blood test can come back with oestrogen sitting inside the normal range, and you can still be oestrogen dominant, because the relationship between oestrogen and progesterone is what produces the symptoms, not the absolute number of either one.

Oestrogen is the stimulating hormone of the female cycle. It builds the uterine lining each month, supports your skin, bones, brain, and cardiovascular system, and supports mood through its effect on serotonin and dopamine receptors. When oestrogen is in the right range and well balanced by progesterone, it supports almost every part of how you feel day to day. When oestrogen is unopposed (meaning progesterone is not keeping up with it), oestrogen's stimulating effects go unchecked.

The uterine lining builds up more than it should, which is what produces heavier bleeding and larger clots. The breast tissue becomes more stimulated and tender, which is what produces premenstrual breast pain and fibrocystic breast changes. The nervous system loses its progesterone buffer, which is where the mood and sleep symptoms come from. Oestrogen also feeds the growth of endometriosis lesions outside the uterus, and feeds the growth of uterine fibroids, which is why both conditions worsen when the oestrogen-to-progesterone ratio is out of balance.

There are two ways a woman develops oestrogen dominance. Either her oestrogen is elevated (from impaired clearance through the liver and gut, from insulin resistance producing more oestrogen in fat tissue, or from environmental oestrogens added on top), or her progesterone has dropped too low to balance her oestrogen, or more commonly a mix of both.

Your liver is how you clear oestrogen out of the body

Every time your body produces oestrogen, the liver is what clears it out once the oestrogen has done its job.

The liver does this through two phases of detoxification. Phase 1 uses a family of enzymes to metabolise oestrogen into smaller compounds, and Phase 2 packages those compounds up so they can be safely removed from the body. Phase 2 uses three main packaging pathways: methylation (which needs B12, folate, B6, and magnesium), glucuronidation (supported by the compounds in cruciferous vegetables), and sulfation (which needs sulphur, found in garlic, onions, eggs, and cruciferous vegetables).

When all of this is working well, the liver keeps up with the oestrogen you are producing and clears it at the rate your body is making it. Phase 2 can slow down for a number of reasons, and in most women I see in clinic, several of these are happening at once. Chronic stress, years on the contraceptive pill, chronic inflammation from poor gut health or blood sugar instability, and alcohol all slow Phase 2 directly by reducing the liver's processing capacity, and they also deplete the specific nutrients the liver's detoxification pathways need to do their work, which is a double hit.

The B vitamins, magnesium, and sulphur (and the other nutrients the liver detox pathways need) can also be depleted by low stomach acid reducing nutrient absorption, gut issues reducing absorption, a diet low in vegetables and protein, and genetic variants that increase demand for these nutrients. Your liver is also processing environmental toxins every day, from paracetamol and other over-the-counter medications, prescription medications, cleaning products, beauty products, perfumes, fragrance in candles and laundry powder, plastics, pesticide residue on food, and car exhaust. Most women have no idea how much of this their liver is processing every day, and over time these exposures accumulate.

If you take pain relief (like paracetamol) every month to get through your period, that is adding to the load on the liver and slowing the oestrogen clearance that is supposed to be happening. The slower the clearance, the more oestrogen dominance, the heavier and more painful the next period becomes, the more pain relief you need to get through it. I see this in clinic in women who have been managing severe period pain with pain relief for years, and it is one of the reasons the symptoms keep getting worse.

When Phase 2 slows, oestrogen clearance slows, and so does the clearance of cortisol, neurotransmitters, medications, and the synthetic oestrogens you are exposed to every day. This is why a sluggish liver does not produce one symptom, it produces clusters of them. Worsening PMS and heavier periods from unopposed oestrogen, increased anxiety and poor sleep from cortisol that is not being cleared properly, slower clearance of histamine (which amplifies hormonal and allergy symptoms), and a general feeling of being wired and inflamed.

When clearance is impaired, oestrogen that your body should have finished with stays in circulation longer than it should, and oestrogen accumulates in the body. This is one of the main reasons I see oestrogen dominance in women with otherwise normal blood tests. Their oestrogen is not being overproduced, it is being under-cleared.

Your gut microbiome plays a direct role in oestrogen balance

Once your liver has finished Phase 1 and Phase 2 of oestrogen detoxification, it packages the oestrogen up and sends it into your digestive tract through bile.

This is Phase 3 of oestrogen clearance, and your gut microbiome plays a direct role in how well it works. From there, your gut is meant to escort that oestrogen out of the body through your stool. Fibre binds to the packaged oestrogen, and regular bowel movements carry it out.

This is where the gut microbiome becomes clinically important. There is a specific collection of gut bacteria called the estrobolome, and one of its jobs is to modulate how much oestrogen leaves the body and how much is recirculated. When the microbiome is diverse, balanced, and the gut is working well, the estrobolome supports oestrogen clearance and the oestrogen your liver packaged up leaves in your stool.

When the microbiome is disrupted (from antibiotics, long-term poor diet, chronic stress, low fibre intake, or gut infections), certain bacteria overproduce an enzyme called beta-glucuronidase. Beta-glucuronidase strips the packaging off the oestrogen that your liver has already processed, which reactivates it and sends it back into circulation through the portal vein. Your liver then has to process the same oestrogen all over again, and while that is happening, the oestrogen is still active in your body and adding to the total oestrogen load.

This is one of the reasons gut symptoms and hormonal symptoms often appear together in clinic. Women with bloating, constipation, reflux, or irritable bowel type symptoms alongside heavy periods, PMS, or endometriosis are often dealing with a microbiome that is contributing directly to their oestrogen load.

Constipation is a particular clinical concern here.

If you are not having a complete bowel movement at least once a day, packaged oestrogen is sitting in your colon for longer, and beta-glucuronidase has more time to reactivate it. Bowel regularity is a hormonal intervention, not just a digestive one.

Insulin is the central mechanism behind PCOS

PCOS is most commonly diagnosed as a hormonal condition, but the hormonal changes in PCOS are almost always the result of a metabolic problem, and the metabolic problem is insulin resistance.

Insulin is the hormone your body releases after you eat, and its job is to move glucose out of your bloodstream and into your cells for energy. In insulin resistance, your cells have become less responsive to insulin, so your pancreas has to produce more and more of it to get the same job done. Your blood sugar readings can still look normal on standard testing, because the pancreas is keeping up by overproducing. But your insulin stays chronically elevated, and that is where the symptoms begin.

Chronically elevated insulin does several things that contribute directly to PCOS. First, it signals to the ovaries to produce more androgens (testosterone and DHEA). This is the mechanism behind the acne along the jawline and chin, the increased facial or body hair, the thinning at the crown or temples, and the difficulty ovulating regularly. The androgen excess is the consequence of insulin being elevated, rather than the starting point.

Second, elevated insulin interferes with ovulation itself by disrupting the signals that would normally trigger ovulation mid-cycle. This is why PCOS cycles become long, unpredictable, or stop altogether. If ovulation is not happening, no progesterone is being produced, which is where the PMS symptoms, the sleep issues, and the mood instability that often run alongside PCOS come from.

Third, elevated insulin promotes weight gain (particularly around the midsection), and fat tissue produces its own oestrogen through an enzyme called aromatase. So a woman with PCOS often has both androgen excess from the ovaries AND additional oestrogen from fat tissue, which is why many women with PCOS carry elements of oestrogen dominance on top of the androgen excess. This is also why the standard PCOS advice to "lose weight" fails so many women. If insulin resistance is what is causing the hormonal issues, the weight is a consequence, not the cause. Addressing insulin resistance first is what shifts everything else, because it addresses the metabolic problem underneath the symptoms.

Chronic stress is one of the biggest hormonal disruptors I see

When I talk about stress in clinic, I am not talking about the occasional busy week or a rough few days. I am talking about the low-grade, always-on stress most women are carrying through work, family, financial pressure, sleep deprivation, and the mental load of managing everything. That kind of chronic stress directly disrupts your hormones through a mechanism called the pregnenolone steal.

Pregnenolone is a hormone precursor your body uses to make both cortisol (your main stress hormone) and progesterone. When you are under chronic stress, your body prioritises cortisol production over everything else, because cortisol is what keeps you functioning through perceived threat. The pregnenolone that would have been used to make progesterone gets redirected into making cortisol instead. The consequence is lower progesterone, sometimes significantly lower, and this happens whether or not you are ovulating normally.

It is one of the reasons women can be ovulating and still have low progesterone, which I covered in the progesterone section above. Low progesterone from the pregnenolone steal is where the PMS symptoms, the anxiety in the second half of the cycle, the waking through the night, and the mood reactivity come from in women who are not in perimenopause and not on hormonal contraception, but whose progesterone is still too low to balance their oestrogen.

Chronic stress also suppresses the signals between your brain and your ovaries that control ovulation. If the signals are disrupted enough, you stop ovulating altogether, which means no progesterone is produced for that cycle, which makes every oestrogen dominance symptom significantly worse. At the same time, chronically elevated cortisol slows liver clearance of oestrogen, which means oestrogen accumulates in the body, and it promotes insulin resistance by reducing the sensitivity of your cells to insulin. So stress is feeding into oestrogen dominance through multiple pathways (slower clearance, lower progesterone to balance it, and more insulin-driven oestrogen production in fat tissue if the stress goes on long enough).

Chronic stress also suppresses thyroid function by reducing the conversion of T4 into the active form of thyroid hormone your cells use. This is why stressed women so often develop thyroid symptoms (fatigue, cold intolerance, weight resistance, hair changes) with normal TSH results on standard testing.

This is why addressing stress is a central part of a clinical hormone plan. Every other hormone in the body is affected by how the nervous system and the HPA axis are functioning. I see this in clinic every week. Women working at capacity, managing everything, eating reasonably well, doing the "right things" nutritionally, and still dealing with worsening PMS, heavier periods, anxiety, sleep issues, and weight gain around the midsection. Chronic stress is almost always the thing that has not been addressed, and until it is, the hormonal work can only go so far.