Perimenopause Symptoms Explained: Common Signs And Why They Happen

What you need to know about perimenopause symptoms:

• Perimenopause symptoms are caused by natural changes in hormone levels and can affect your menstrual cycle, sleep, mood, energy and overall wellbeing.
• Common signs of perimenopause include irregular periods, hot flushes, night sweats, fatigue, headaches, bloating, mood changes and changes to hair or body composition.
• Everyone's experience is different. Symptoms can vary in type, intensity and duration, and may come and go throughout the transition to menopause.
• Understanding why symptoms happen can help you recognise the changes you're experiencing and know when to seek support from a healthcare professional.

Perimenopause can bring a wide range of changes, from hot flushes and changes in your menstrual cycle to disrupted sleep, shifts in mood and brain fog. While these symptoms can feel unexpected, they're a normal part of the hormonal changes that happen as your body transitions towards menopause¹.

Every person's experience of perimenopause is different. Some people notice only a few mild symptoms, while others find the changes have a greater impact on their day-to-day life.

This guide explains some of the most common signs of perimenopause, why they happen, and how changing hormone levels can influence the way you feel. 

Why do perimenopause symptoms happen?

Perimenopause symptoms are caused by changing hormone levels, particularly fluctuations in oestrogen and progesterone. Rather than declining steadily, these hormones naturally rise and fall throughout the transition to menopause. Because they influence many different systems throughout the body, it's normal to notice a range of physical and emotional changes¹.

Some of the ways changing hormones can affect the body include:

• Sleep. Sleep changes are common during perimenopause. Hormonal fluctuations can make it harder to fall asleep or stay asleep, and these changes often become more noticeable as women move through the menopausal transition¹.
• Mood. Oestrogen interacts with brain chemicals involved in mood regulation, including serotonin and noradrenaline. As hormone levels change, some people notice changes in mood, increased nervousness, or feeling more emotionally sensitive¹.
• Body temperature. Fluctuating oestrogen levels are thought to affect the body's temperature regulation, which may help explain symptoms like hot flushes and night sweats¹.
• Energy and metabolism. Oestrogen also plays a role in metabolism and energy regulation. As hormone levels change, some people notice shifts in their energy levels or changes to the way their body stores and uses energy².

Everyone experiences perimenopause differently. Symptoms may come and go, change from one month to the next, or vary in intensity over time. For many people, symptoms gradually improve after menopause, although the timing and duration are different for everyone³.

Early perimenopause symptoms

Early perimenopause symptoms can begin several years before menopause itself. At first, the changes are often mild or come and go, which can make them easy to miss or difficult to recognise as part of the menopausal transition³.

Some of the early signs include changes to your menstrual cycle, disrupted sleep, shifts in mood, fatigue, headaches and changes in temperature regulation³. Because these symptoms don't always happen consistently, it's common not to realise that perimenopause may be the cause.

Changes to periods during perimenopause

For many people, changes to their menstrual cycle are one of the first signs of perimenopause. 

Common perimenopause period changes include irregular periods, heavier or lighter bleeding, shorter or longer cycles, and missed periods. These changes happen because ovulation becomes less predictable, causing the hormone patterns that regulate your menstrual cycle to fluctuate³.

While changes to your periods are a normal part of perimenopause, it's important to speak with your healthcare professional if you experience very heavy bleeding, bleeding between periods, bleeding after sex, or any other changes that concern you.

Common symptoms of perimenopause 

What are perimenopause symptoms? Beyond changes to your menstrual cycle, perimenopause can bring a range of physical, emotional and cognitive symptoms. Everyone's experience is different, so you may notice only a few of these changes or several at the same time.

Understanding why these symptoms happen can make them easier to recognise and help you find the support that's right for you.

Hot flushes and night sweats

Hot flushes and night sweats are among the most common symptoms of perimenopause. They're thought to happen because changing oestrogen levels affect the body's ability to regulate temperature³ ⁴. A hot flush is a sudden feeling of warmth, often accompanied by flushing and sweating, while night sweats are hot flushes that happen during sleep.

Night sweats can interrupt your sleep, leaving you feeling less rested the next day. Research suggests they often become more frequent as women get closer to their final menstrual period, although everyone's experience is different³ ⁴.

Why sleep may feel different during perimenopause

Sleep during perimenopause is often affected by several factors compounding one another. Night sweats can wake you during the night, hormonal fluctuations can affect sleep quality directly, and repeated interruptions can leave you feeling less rested overall³.

The knock-on effect matters. Poor or broken sleep can influence energy levels and mood the following day, which is one reason sleep is worth prioritising during this stage. Because sleep affects mood, energy and overall wellbeing, finding ways to support good sleep can make a meaningful difference during this stage of life. 

Perimenopause fatigue

Feeling more tired than usual is a common experience during perimenopause. Fatigue is often linked to several factors working together, including disrupted sleep, changing hormone levels, stress and changes in mood³.  Because these factors overlap and reinforce one another, fatigue can feel more persistent than ordinary tiredness.

Headaches during perimenopause

Perimenopause headaches may become more frequent or feel different as hormone levels fluctuate. For some women, existing headaches or migraines change in frequency or intensity during this stage⁵. Stress and sleep disruption may also influence headaches.

If headaches become more frequent or severe, a GP can help identify what may be contributing.

Perimenopause bloating

Hormonal changes during perimenopause can influence digestion and the way your body regulates fluid, which may contribute to bloating⁶. Some people also experience perimenopause nausea or other digestive changes, although these symptoms typically come and go.

As with many perimenopause symptoms, these experiences can feel inconsistent throughout the month and vary considerably from person to person, appearing at some times and easing at others.

Mood changes and emotional symptoms

Hormonal fluctuations can influence emotional wellbeing alongside physical symptoms. Some women notice irritability, greater emotional sensitivity, lower motivation, anxiety or a feeling of being overwhelmed, or a sense of brain fog and reduced mental clarity⁷.

Mood changes are a recognised part of perimenopause for many people, and they're just as important to acknowledge as the physical symptoms. If low mood, anxiety, or other emotional symptoms feel persistent or difficult to manage, it’s best to speak with your GP.

Perimenopause weight gain

Changes in body weight or body composition are common during midlife, but hormones are only one part of the picture. As oestrogen levels change, the body may begin storing fat differently⁸. Sleep, stress, physical activity and nutrition also play an important role⁸.

Perimenopause hair loss

Some women notice increased hair shedding or changes in hair thickness during perimenopause⁹. Hair loss during perimenopause may be linked to changing hormone levels, the natural hair growth cycle, and other factors such as stress or overall health⁹. 

Because the hair follicle is sensitive to hormonal changes, the transition can affect how hair grows and sheds. As with other symptoms, the extent of these changes varies from person to person, and a GP or dermatologist can help if hair loss of perimenopause becomes a particular concern.

Why symptoms can feel different for everyone

There isn't one typical perimenopause experience. The type, timing and intensity of symptoms can vary from person to person, and even from one month to the next. Some people notice only a few mild changes, while others experience a wider range of symptoms throughout the transition.

These differences are a normal part of perimenopause. Rather than comparing your experience with someone else's, it can be more helpful to pay attention to your own symptoms and patterns over time.

Understanding your perimenopause symptoms

Perimenopause can bring changes that affect many different parts of the body, from your menstrual cycle and sleep to your mood, energy and concentration. While these symptoms can sometimes feel unexpected, they're a normal response to changing hormone levels during this stage of life.

Understanding what's happening in your body can make it easier to recognise your symptoms and find the support that's right for you. If symptoms are affecting your daily life or you have concerns about the changes you're experiencing, speak with your healthcare professional to discuss the options available.

Want more? Explore articles on the Swisse Wellness Hub, including the different menstrual cycle phases and a guide to nutrition after 50. 

References:

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