Understanding Perimenopause: Why Your Body Feels Different (and What’s Really Happening)

Menopause Isn’t a Sudden Change

Menopause is often described as a moment — a point in time where periods stop and a new phase begins.

But for most women, that’s not how it feels.

Instead, it can be a slow, confusing shift. Your body may look the same on the outside, but internally things feel different. Energy changes. Sleep becomes disrupted. Focus isn’t as sharp. You might feel more irritable, more forgetful, or simply not quite like yourself.

What makes it more frustrating is that these symptoms don’t always seem connected.

However, there is a clear biological explanation.

Perimenopause Is a Hormonal Transition

The phase leading up to menopause, known as perimenopause, can last for several years. During this time, levels of oestrogen and progesterone don’t just decline — they fluctuate.

Oestrogen, in particular, becomes more variable before it gradually reduces overall. This matters because oestrogen is not just a reproductive hormone. It acts as a signalling molecule throughout the body, influencing multiple systems simultaneously.

When these signals begin to change, the systems that rely on them must adapt.

This is why perimenopause doesn’t present as one single symptom, but as a wide range of changes that can feel unpredictable.

Oestrogen Is Active Throughout the Body

Oestrogen receptors are widely distributed in tissues far beyond the ovaries and uterus. They are found in the brain, the cardiovascular system, the gastrointestinal tract, the skin, bones, and the urogenital tissues.

From a physiological perspective, oestrogen plays a role in regulating inflammation, maintaining tissue structure, supporting blood flow, and influencing neurotransmitter activity.

As levels decline, these processes begin to shift.

For example, in the brain, oestrogen modulates neurotransmitters such as serotonin and dopamine, both of which are involved in mood, focus, and cognitive processing. It also plays a role in synaptic plasticity — the brain’s ability to adapt and form new connections.

This helps explain why many women experience brain fog, forgetfulness, or reduced mental clarity during perimenopause. The brain is not deteriorating, but rather adjusting to a different hormonal environment.

The Impact on Sleep, Mood, and Temperature Regulation

Oestrogen also interacts with areas of the brain responsible for regulating sleep and body temperature, including the hypothalamus.

As hormonal signalling changes, this regulation can become less stable. This may result in disrupted sleep patterns, night sweats, and increased sensitivity to temperature changes.

Sleep disruption alone has significant downstream effects. Poor sleep is strongly linked in research to increased fatigue, reduced cognitive performance, and changes in mood regulation. This is one reason why irritability and low energy often accompany perimenopause.

Digestive Changes and the Gut

Less commonly discussed is the role of oestrogen in the gastrointestinal system.

Oestrogen receptors are present along the gut lining, and the hormone influences gut motility, sensitivity, and even the composition of the gut microbiome.

As levels fluctuate, some women notice increased bloating, changes in bowel habits, or digestive discomfort. These symptoms are often attributed solely to diet, stress, or ageing, but hormonal changes can be a contributing factor.

Bones, Joints, and Structural Health

Oestrogen is also essential for maintaining bone density and joint health. It helps regulate the balance between bone breakdown and bone formation.

As oestrogen declines, this balance shifts, leading to an increase in bone resorption. Research suggests women can lose up to 10% of their bone density in the early postmenopausal years.

In addition, oestrogen supports collagen production, which contributes to the integrity of joints, skin, and connective tissues. Reduced levels may lead to joint stiffness, aches, and a sense of reduced resilience in the body.

Skin, Hair, and Cardiovascular Health

Changes in skin and hair are also linked to declining oestrogen. The hormone supports collagen synthesis and hair growth cycles, so reductions can lead to thinner hair and less elastic, drier skin.

At the same time, oestrogen has a protective effect on the cardiovascular system. It supports healthy blood vessels and helps regulate cholesterol levels. While this doesn’t always produce obvious symptoms, it does make midlife an important time to pay attention to long-term heart health.

A Whole-Body Adaptation

When you step back and look at the full picture, perimenopause is not a collection of unrelated issues.

It is a whole-body adaptation to a changing hormonal environment.

Each system — the brain, the gut, the musculoskeletal system, the skin — is responding to shifts in signalling that have been present for decades.

This is why symptoms can feel widespread and, at times, confusing.

Understanding Changes Everything

Perhaps one of the most important things to recognise is that this is not a sign that your body is failing.

It is responding, adjusting, and recalibrating.

When you understand the underlying biology, symptoms begin to feel less random. You can see the connections, make more informed decisions, and approach this phase with greater clarity and confidence.

A New Way to Approach Perimenopause

This is exactly why I’m starting a mini series focused on perimenopause.

The aim is to make the science more understandable, to connect the dots between symptoms, and to help you feel more in control of what’s happening in your body.

Because with the right knowledge and support, this transition becomes far less overwhelming — and far more manageable.

More coming soon. 🤍