Introduction

If you have been experiencing symptoms such as anxiety, low mood, sleep disruption, brain fog, fatigue, or changes in your physical health during your forties or early fifties, you may have wondered why your body suddenly feels different.

Many women describe feeling as though their mind and body are not functioning the way they used to. Tasks that once felt manageable may now feel overwhelming. Sleep may become lighter or disrupted. Concentration may feel more effortful. Emotional reactions may feel stronger than expected.

These changes are often linked to fluctuating and declining hormone levels during perimenopause, particularly the hormones oestrogen and progesterone. While these hormones are commonly associated with reproductive health, they actually influence many systems throughout the body including brain function, mood regulation, cardiovascular health, metabolism, bones, skin, and immune functioning (Davis et al., 2015; Soares, 2014).

Understanding how these hormones influence the body can help explain many of the symptoms women experience during this life stage.

The Role of Oestrogen in the Body

Oestrogen plays a critical role in maintaining the health and function of many organs and systems in the body. It has widespread effects on the brain, cardiovascular system, bones, metabolism, skin, and reproductive tissues (Davis et al., 2015).

During the perimenopausal transition, oestrogen levels fluctuate and gradually decline, which can affect multiple aspects of physical and psychological wellbeing.

Oestrogen and Brain Function

Oestrogen has important effects on the brain. It supports brain cell communication, helps regulate neurotransmitters involved in mood, and improves blood flow to brain tissue (Maki & Jaff, 2022).

Research shows that oestrogen can influence levels of neurotransmitters including serotonin, dopamine, acetylcholine, noradrenaline and melatonin, which are involved in mood regulation, memory, sleep and motivation (Soares, 2014).

Because of this, declining oestrogen levels during perimenopause may contribute to symptoms such as:

• Brain fog
• Difficulty concentrating
• Memory lapses
• Increased anxiety
• Reduced mood stability
• Lower energy levels

Many women describe feeling mentally slower or struggling to find words in conversation. These cognitive changes are common during hormonal transition and are believed to be related to the effects of oestrogen on brain function (Maki & Jaff, 2022).

Oestrogen and Mood

Oestrogen also has a direct influence on emotional wellbeing. It helps regulate the neurotransmitters that influence mood and stress responses.

As oestrogen fluctuates during perimenopause, some women experience:

• Anxiety
• Mood swings
• Irritability
• Low mood
• Increased emotional sensitivity

Studies have found that fluctuations in oestrogen during the menopausal transition are associated with increased risk of mood symptoms for some women (Bromberger & Epperson, 2018).

Oestrogen and Sleep

Oestrogen influences sleep regulation by affecting melatonin production and body temperature control. As hormone levels change, women may experience:

• Difficulty falling asleep
• Frequent waking
• Night sweats
• Poor sleep quality

Sleep disruption can then worsen other symptoms such as irritability, low mood and fatigue (Freeman, 2015).

Oestrogen and Heart Health

Oestrogen supports cardiovascular health by helping maintain healthy blood vessels and regulating cholesterol and blood pressure levels (Davis et al., 2015).

It also supports endothelial function, which helps maintain healthy blood flow throughout the body. Changes in oestrogen levels during menopause are associated with changes in cardiovascular risk profiles.

Oestrogen and Metabolism

Oestrogen helps regulate metabolism including blood sugar levels, cholesterol balance and fat metabolism. As levels decline, women may notice changes in weight distribution or metabolic function (Davis et al., 2015).

Some women report:

• Weight gain
• Changes in appetite
• Reduced energy
• Increased fatigue

Oestrogen and Bone Health

Oestrogen plays an important role in maintaining bone density. Reduced oestrogen levels during menopause can contribute to gradual bone loss and increased risk of osteoporosis (Hale & Burger, 2009).

Women may also notice increased joint stiffness or discomfort.

Oestrogen and Skin

Oestrogen supports collagen production and skin elasticity. It also helps maintain skin hydration and blood supply to the skin.

As levels decline, women may notice:

• Drier skin
• Reduced skin elasticity
• Changes in skin texture

Oestrogen and Urogenital Health

Oestrogen supports healthy tissues in the vagina and urinary tract. Changes in hormone levels can affect lubrication, tissue health and urinary function.

Symptoms may include:

• Vaginal dryness
• Pain during sex
• Urinary urgency
• Increased urinary tract infections

These symptoms are sometimes referred to as genitourinary syndrome of menopause (Australasian Menopause Society, 2023).

The Role of Progesterone in the Body

Progesterone is another important hormone that works alongside oestrogen. It plays a key role in regulating the menstrual cycle and supporting pregnancy, but it also influences the brain, immune system, metabolism and sleep (Davis et al., 2015).

Progesterone levels also fluctuate and decline during perimenopause.

Progesterone and Brain Function

Progesterone helps brain cells communicate effectively and supports healthy nerve functioning.

It has calming effects on the nervous system and may support emotional regulation and mental clarity.

Changes in progesterone levels can contribute to:

• Anxiety
• Irritability
• Difficulty concentrating
• Reduced emotional resilience

Progesterone and Sleep

Progesterone is known to have sleep promoting properties. It can help regulate the sleep cycle and support restful sleep.

Declining progesterone levels during perimenopause may therefore contribute to sleep difficulties including:

• Trouble falling asleep
• Restless sleep
• Waking during the night

Poor sleep can then affect mood, energy and cognitive functioning.

Progesterone and Psychological Wellbeing

Progesterone has calming effects on the brain and may help reduce anxiety and promote emotional stability (Soares, 2014).

As progesterone levels fluctuate, some women may notice:

• Increased anxiety
• Feeling tense or on edge
• Mood changes
• Reduced emotional tolerance to stress

Progesterone and Metabolism

Progesterone also plays a role in blood sugar regulation and how the body uses energy. Changes in progesterone levels may influence appetite, energy levels and metabolism.

Progesterone and Muscles

Progesterone supports muscle health and can help reduce muscle spasms. Some women may notice changes in muscle tension or physical comfort during hormonal fluctuations.

Progesterone and the Immune System

Progesterone also has anti inflammatory effects and can influence immune system functioning. Changes in this hormone may influence inflammation and general physical wellbeing.

Why Hormonal Changes Affect So Many Systems

Many women are surprised to learn how widely hormones influence the body.

Oestrogen and progesterone affect:

• Brain function
• Mood regulation
• Sleep cycles
• Metabolism
• Cardiovascular health
• Bone density
• Skin health
• Muscle function
• Immune system activity
• Reproductive and urogenital health

Because these hormones affect so many systems, fluctuations during perimenopause can produce a wide range of symptoms across both physical and psychological domains.

When to Seek Support

If hormonal changes are affecting your mood, sleep, concentration, energy, or quality of life, it may be helpful to speak with a healthcare professional.

Support may include:

• Medical assessment with a GP
• Hormone related health discussions
• Psychological therapy to support emotional wellbeing
• Lifestyle and stress management strategies

Many women benefit from addressing both the biological and psychological aspects of perimenopause.

Support from Kristie Clarke Psychology

Kristie Clarke is a Clinical Psychologist who supports women navigating the psychological impact of perimenopause and menopause.

Many women experience symptoms such as anxiety, low mood, irritability, emotional overwhelm and cognitive fog during this stage of life. Through psychological therapy and supportive counselling, Kristie helps women better understand these experiences and develop practical strategies to support emotional wellbeing.

If you are experiencing changes in mood, sleep, stress tolerance or concentration during perimenopause, you may wish to contact Kristie Clarke Psychology to learn more about available support.

Important Note

This article is intended for informational purposes and is not a substitute for professional medical advice, diagnosis or treatment.

If you have concerns about your health or symptoms, please consult your GP or a qualified healthcare professional.

References

Australasian Menopause Society. (2023). Perimenopause and menopause information for women. https://www.menopause.org.au

Bromberger, J. T., & Epperson, C. N. (2018). Depression during and after the menopausal transition. Current Psychiatry Reports, 20(7), 55.

Davis, S. R., Lambrinoudaki, I., Lumsden, M., Mishra, G., Pal, L., Rees, M., Santoro, N., & Simoncini, T. (2015). Menopause. Nature Reviews Disease Primers, 1, 15004.

Freeman, E. W. (2015). Associations of depression with the transition to menopause. Menopause, 22(11), 1143–1150.

Hale, G. E., & Burger, H. G. (2009). Hormonal changes and biomarkers in the menopausal transition. Best Practice & Research Clinical Obstetrics & Gynaecology, 23(1), 7–23.

Maki, P. M., & Jaff, N. G. (2022). Cognitive changes during the menopausal transition. Obstetrics and Gynecology Clinics of North America, 49(3), 431–444.

Soares, C. N. (2014). Mood disorders in midlife women. Obstetrics and Gynecology Clinics of North America, 41(3), 565–578.