Written by Christina Hanley BHSc (Nutritional Medicine) | ANTA Member #20854 | Nutritionist & Health Content Lead at Mr Vitamins.

Reviewed by Yurie Sato BHSc (Naturopathy) | Qualified Naturopath | NHAA Member #157018 | Assistant Store Manager at Mr Vitamins with 6 years of clinical experience. 

Published 1st September | Last reviewed 31 August 2026 | Reviewed every 12 months or sooner where new clinical evidence emerges. [How we review health content] · [Meet our practitioner team] 

For many women, perimenopause arrives as a series of changes that feel both irritating and unsettling, and often years earlier than expected. Sleep shifts. Periods change. Mood becomes less predictable. And the stress that used to roll off suddenly doesn't.

That last part isn't a coincidence, and it's the piece most often left out of the conversation.

What you'll learn:

• What actually changes hormonally in perimenopause
• Why stress and perimenopause amplify each other
• Commonly reported symptoms
• Herbs and nutrients traditionally used during this transition
• When to see your doctor

What Actually Changes in Perimenopause

The common assumption is that oestrogen simply declines. The reality is more interesting, and it explains a lot about why symptoms feel so erratic.

Progesterone tends to fall first. Progesterone is produced in meaningful amounts only after ovulation. As ovulation becomes less frequent and less reliable, which typically begins in the late thirties or early forties, progesterone production becomes intermittent, then low.¹

Oestrogen becomes erratic rather than low. During early and mid-perimenopause, oestrogen doesn't decline smoothly. It fluctuates, sometimes surging above premenopausal levels and sometimes dropping sharply.¹ This is why symptoms can vary so much from one month to the next.

The relative balance between the two shifts. Because progesterone often declines earlier and more consistently than oestrogen, the ratio between them changes, even in cycles where oestrogen isn't high in absolute terms.

In complementary medicine, this relative shift is sometimes described as "oestrogen dominance." It's worth being clear that this is a descriptive term used in that field rather than a formal medical diagnosis, and it isn't measured by a standard blood test. The underlying endocrinology includes reduced ovulation, low progesterone and fluctuating oestrogen.¹ 

Perimenopause can last a long time. The transition commonly runs for several years and can extend to eight to ten.¹

Why Stress and Perimenopause Amplify Each Other

The relationship runs both ways. Oestrogen has a regulatory role in the hypothalamic-pituitary-adrenal axis, your central stress response system. As oestrogen becomes erratic, that regulation becomes less stable, which means the same stressors can produce a bigger response than they used to.²

And stress appears to worsen symptoms. Research examining midlife women has found that cortisol dysregulation is associated with more frequent hot flushes recorded in daily diaries.³ A separate study found that women with more severe and bothersome perimenopausal vasomotor symptoms showed altered HPA axis activity.²

The direction of cause isn't settled. Researchers are clear that it's not yet established whether hot flushes alter HPA axis activity or the reverse.² What the evidence does support is that the two travel together, and that's useful to know regardless of which drives which.

There's a sleep loop too. Night sweats and disrupted sleep are common during this transition, and poor sleep heightens stress reactivity the following day, which in turn tends to worsen symptoms. It's a cycle that can be interrupted at any point.

Commonly Reported Symptoms

The number, frequency and severity vary enormously between women. Some experience very little; others find it genuinely disruptive.

Commonly reported during perimenopause:

• Irregular or changed periods, including heavier or more painful periods
• Hot flushes and night sweats
• Disturbed sleep
• Mood changes and increased irritability
• Fatigue and lower energy
• Breast tenderness
• Fluid retention and bloating
• Changes in libido
• Changes in body composition and weight
• Difficulty concentrating, or "brain fog"
• Reduced tolerance for stress

If any of these are significantly affecting your quality of life, that's a reason to see your GP rather than to manage alone.

Herbs and Nutrients Traditionally Used During This Transition

“Where supplementation fits, these ingredients are commonly used, with some having genuine human research behind them and others resting largely on long traditional use" Yurie Sato BHSc (Naturopathy) | Qualified Naturopath | NHAA Member #157018 | Assistant Store Manager at Mr Vitamins with 6 years of clinical experience. 

Always read the label and follow the directions for use. Vitamin and mineral supplements should not replace a balanced diet. If symptoms persist, talk to your health professional. Speak with a qualified practitioner before starting herbal supplements, particularly if you take prescription medication or use hormonal contraception.

Foundations That Support This Transition

• Consistent sleep and wake times: sleep regularity affects both symptom severity and stress tolerance
• Resistance training and weight-bearing exercise: supports muscle and bone through a period when both change
• Adequate protein: intake requirements often rise
• Morning light and daily movement: supports circadian rhythm, which underpins sleep and mood
• Limiting alcohol and caffeine: both are common triggers for hot flushes and night sweats
• Genuine stress management: given the HPA axis relationship above, this is doing more than it looks

When to See Your Doctor

Please do see your GP if:

• Symptoms are affecting your work, relationships or quality of life
• Your periods become very heavy, very frequent, or you bleed between periods or after sex
• You're experiencing significant mood changes or persistently low mood
• You're under 45 and periods have become irregular or stopped
• You'd like to discuss menopausal hormone therapy

One important point. Menopausal hormone therapy is an effective, evidence-based medical treatment for many women, and a conversation worth having with your doctor. 

Also worth knowing: several perimenopause symptoms overlap with thyroid conditions and iron deficiency, both of which are common in this age group and both easily tested. 

Frequently Asked Questions

What you need to know

Perimenopause isn't a straightforward decline in oestrogen. It's a period of hormonal fluctuation, usually with progesterone falling first and it can last years.

Oestrogen helps regulate your stress response system, so as it fluctuates, your tolerance for stress genuinely changes, and higher stress appears to travel with more severe symptoms. This is why it's important to learn how to manage your stress levels appropriately.

Sleep, movement, protein intake and stress management are the foundations. Herbs and nutrients may support you alongside them, and your GP is the right person to talk to about anything affecting your quality of life.

Visit your local Mr Vitamins store or book a free 10-minute consultation with one of our qualified practitioners to talk through what might suit you.

This article is general information only and is not intended as medical advice, diagnosis or treatment. It does not take into account your individual health circumstances. Always read the label and follow the directions for use. Vitamin and mineral supplements should not replace a balanced diet. Consult your GP or a qualified health practitioner before starting any new supplement, particularly if you are pregnant, breastfeeding, taking prescription medication, using hormonal contraception, or managing a health condition. If symptoms persist, talk to your healthcare professional.

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