patient information // MENOPAUSE
Understanding menopause, perimenopause & early menopause
A comprehensive guide to help you understand what's happening to your body, recognise the signs at every stage, and know when specialist support can help.
Written by a BMS Menopause Specialist
Evidence-based (NICE & BMS guidelines)
Last reviewed: May 2026
MENOPAUSE
What is menopause?
Menopause is a natural stage of life that every woman will experience. Understanding what's happening – and what to expect – can make a real difference to how you feel.
Menopause is the point when your periods stop permanently because your ovaries no longer release eggs and your production of oestrogen and progesterone declines significantly. It's confirmed after 12 consecutive months without a menstrual period.
Most women reach menopause between the ages of 45 and 55, with the average age in the UK being 51. But the transition – and the symptoms that come with it – often begin years earlier, during a phase called perimenopause.
The three stages of menopause
Whilst menopause itself is defined as the point at which your periods have stopped for 12 months, it can be helpful to think about menopause as a journey through three connected stages.
Where you are in this journey affects which symptoms you experience and which treatment options may be most helpful.
01
Perimenopause
The transition phase when hormone levels begin to fluctuate, often starting in your mid-40s (sometimes earlier). Periods become irregular and symptoms like hot flushes, mood changes, and sleep disruption may begin. This can last 4–8 years.
02
Menopause
The point when you've had no period for 12 consecutive months.
​
The average age is 51 in the UK, but it varies widely. Symptoms from perimenopause may continue or change.
03
Postmenopause
The years following menopause. Oestrogen levels remain low. Some symptoms ease, but others – such as vaginal dryness, urinary symptoms joint stiffness, or changes to bone density – may persist. Ongoing support and treatment can help.
How long does menopause last?
This is one of the most common questions women ask, and the honest answer is: it varies. The perimenopause transition typically lasts between 4 and 8 years, though for some women it can be shorter or longer. Symptoms like hot flushes tend to last around 4–5 years on average, but some women experience them for much longer. Postmenopause symptoms – particularly vaginal dryness and urinary symptoms – as well as changes to bone health can continue indefinitely without treatment.
There's no fixed timeline, which is why personalised care matters. A specialist can help you understand where you are in your journey and what to expect next.
SYMPTOMS
Menopause & perimenopause symptoms
Hot flushes and night sweats are the most well-known symptoms, but menopause can affect almost every part of your body and mind. Many women don't realise that symptoms like anxiety, brain fog, or joint pain can be related to hormonal changes.
Common and lesser-known symptoms
These symptoms can start during perimenopause – often years before your periods stop – and may continue into postmenopause. Not every woman experiences all of them, and severity varies widely.
Hot flushes & night sweats
Sudden waves of heat, flushing, and sweating – often the first symptom women notice. Can disrupt sleep and daily life.
Brain fog & concentration
Difficulty focusing, forgetfulness, and feeling mentally "cloudy." Often one of the most distressing symptoms for working women.
Anxiety & mood changes
New or worsening anxiety, irritability, low mood, or feelings of overwhelm – often mistaken for depression or stress rather than hormonal change.
Sleep disruption
Difficulty falling or staying asleep, waking in the early hours, or unrefreshing sleep – beyond just night sweats.
Joint pain & stiffness
Aching joints, morning stiffness, or new muscle pain. Often not connected to menopause, but oestrogen decline is a known cause.
Low energy & fatigue
Persistent tiredness that doesn't improve with rest. Can affect motivation, exercise tolerance, and everyday tasks.
Reduced libido
Loss of interest in sex, reduced arousal, or discomfort during intimacy – often connected to vaginal dryness. Testosterone may play a role.
Weight changes
Weight gain – particularly around the middle – or difficulty losing weight. Hormonal shifts change how your body stores fat.
Heart palpitations
Racing heart, fluttering, or a pounding sensation in your chest. Can be alarming but is a recognised menopause symptom.
Hair & skin changes
Thinning hair, dry or itchy skin, or changes in skin texture. Oestrogen plays a key role in collagen production.
Period changes
Changes in flow, regularity, and length of periods occur during perimenopause. One of the earliest signs of hormonal change.
Headaches & migraines
New headaches, or existing migraines related to periods may become worse due to hormone fluctuations during perimenopause.
Many of these symptoms overlap with other conditions – thyroid disorders, ADHD, depression, and anxiety can all share symptoms with menopause, or can present differently in women who are going through the menopause transition. If you're unsure whether your symptoms are related to menopause or something else, a specialist assessment can help you get the right diagnosis.
perimenopause
What is perimenopause?
Perimenopause is the transition phase leading up to menopause – when your hormone levels begin to fluctuate and your body starts to change. For many women, this is when symptoms first appear.
During your reproductive years, your ovaries produce oestrogen and progesterone in a regular cycle. In perimenopause, this cycle becomes unpredictable – hormone levels rise and fall unevenly, causing the symptoms many women experience. Perimenopause can begin in your mid-40s, though for some women it starts in the late 30s or early 40s.
When does perimenopause start?
For most women, perimenopause starts in their mid-40s, although it can happen earlier or later than this. The timeline below offers what an ‘average’ journey through perimenopause into menopause may look like, but it’s important to remember that every woman experiences this differently.
How long does perimenopause last?
On average, perimenopause lasts between 4 and 8 years, though for some women it can be shorter and for others it may last over a decade. The length of time varies from woman to woman and isn't something that can be predicted in advance. What matters most is that you don't need to wait it out – treatment and support are available at every stage.
How is perimenopause diagnosed?
Perimenopause is usually diagnosed based on your symptoms and medical history, not blood tests. NICE guidelines state that hormone blood tests are not needed to diagnose perimenopause in women over 45 – your symptoms are enough. For women under 45, blood tests may be recommended to rule out other causes and to check for early menopause.
You don't need a blood test to start getting help. If you're experiencing symptoms that are affecting your quality of life, you don't need to wait for blood tests or a GP referral to seek specialist support. Dr Radley can assess your symptoms, discuss your options, and create a treatment plan tailored to where you are right now.
early menopause & poi
Early menopause & premature ovarian insufficiency (POI)
For some women, menopause comes much earlier than expected. If you're experiencing menopause before the age of 45, or before 40, it's important to see a specialist – both for symptom management and for your long-term health.
Early
menopause
Menopause that occurs between the ages of 40-45. Around 5% of women experience this. It can happen naturally or be triggered by medical treatments. Symptoms are the same as menopause at the typical age, but the health implications – particularly for bone density and heart health – are more significant because of the longer period of oestrogen deficiency.
Premature ovarian insufficiency (POI)
Previously called "premature menopause," POI occurs before the age of 40 and affects around 1 in 100 women. Triggers can include autoimmune conditions or medical treatments such as chemotherapy or pelvic radiotherapy, and genetics may also play a role. Women with POI are usually recommended HRT at least until the average age of natural menopause (51) to protect bone, heart, and brain health.
How is perimenopause diagnosed?
Perimenopause is usually diagnosed based on your symptoms and medical history, not blood tests. NICE guidelines state that hormone blood tests are not needed to diagnose perimenopause in women over 45 – your symptoms are enough. For women under 45, blood tests may be recommended to rule out other causes and to check for early menopause.
Dr Radley has specific experience in managing early menopause and POI. This includes working with women who've experienced menopause as a result of cancer treatment, those with autoimmune conditions, and women who've been diagnosed with POI and need long-term hormone management. If you're under 45 and experiencing menopause symptoms, specialist guidance is important.
Surgical menopause
Menopause after surgery
Surgical menopause happens when your ovaries are removed during an operation – most commonly as part of a hysterectomy. Unlike natural menopause, it happens suddenly, and the effects can be more intense.
When both ovaries are removed (bilateral oophorectomy), your body's main source of oestrogen is lost immediately. This means menopause symptoms can start within days of surgery rather than developing gradually over months or years. Many women find the sudden onset more difficult to manage than natural menopause.
If only the uterus is removed (hysterectomy) but the ovaries are kept, you won't have periods but your ovaries will continue producing hormones – though they may stop working earlier than they would have otherwise.
Why surgical menopause needs specialist support
Symptoms can be more severe due to the sudden drop in hormones, rather than the gradual decline of natural menopause
HRT is usually recommended, particularly if surgery happens before the age of natural menopause, and the type of HRT differs depending on whether your uterus was removed
Long-term bone and cardiovascular health need monitoring, especially if surgery occurred at a young age
Emotional and psychological impact can be significant – grief, identity, and adjustment all play a role alongside the physical symptoms
NEURODIVERGENCE & MENOPAUSE
Menopause & neurodivergence
If you're neurodivergent – which includes autism and ADHD – menopause can affect you differently. Symptoms can overlap, interact, and be harder to untangle. Specialist understanding makes a huge difference in feeling heard and establishing a treatment plan that fits your unique needs.
Menopause & ADHD
Oestrogen plays a role in dopamine regulation, which means declining hormone levels during perimenopause can have a pronounced effect on ADHD symptoms. Women with ADHD often report that their existing symptoms worsen significantly – increased difficulty concentrating, emotional dysregulation, executive function challenges, and sensory sensitivity. Stimulant medication that previously worked well may become less effective.
Menopause & autism
For autistic women, the hormonal fluctuations of perimenopause can increase sensory overwhelm, disrupt routines, and intensify anxiety. Menopausal symptoms like sleep disruption, temperature sensitivity, and cognitive changes can be particularly distressing when layered on top of existing sensory and processing differences.
Why neurodivergence in menopause needs specialist support
Whether you have ADHD, autism, or both (AuDHD), there's a risk of misdiagnosis – menopause symptoms attributed to ADHD or autism (or vice versa), or both dismissed as "just stress."
Many women who have spent their lives coping with neurodivergence find themselves suddenly struggling during the menopause transition, often needing more support as symptoms are exacerbated.
A specialist who understands both menopause and neurodivergence can help you separate what's hormonal from what isn't, ensure your treatment plan accounts for the whole picture, and facilitate referrals for further support.
Dr Radley has specific experience supporting neurodivergent women through menopause. Whether you have an existing ADHD or autism diagnosis, or you're exploring whether your symptoms might have a neurodivergent component, a specialist consultation can help you understand what's happening and what will help.
when to see a specialist
When should you see a menopause specialist?
You don't need to wait until your symptoms are severe – or until your GP suggests it – to get specialist help. There are some situations where seeing a menopause specialist is particularly important:
Your symptoms are affecting your quality of life – work, relationships, sleep, or daily functioning
You're under 45 and think you may be experiencing early menopause
You've been to your GP but feel your symptoms haven't been taken seriously or fully addressed
You're on HRT but it's not working as well as you'd hoped, or you're experiencing side effects
You have a complex medical history – including breast cancer, neurodivergence, or surgical menopause
You want to explore treatment options your GP may not offer, such as testosterone therapy or certain newer, non-hormonal treatments
You're confused about whether your symptoms are menopause or something else
