You may be sleeping worse than you used to, losing words halfway through a sentence, or snapping at people you love. Your periods might be a little shorter, a little heavier, or simply less predictable. None of it feels dramatic enough to name, so it gets filed under stress, a busy year or getting older.
The confusion is understandable. Perimenopause usually begins in the mid to late forties, years before the final period, and its first signs are rarely the hot flushes everyone expects.1 Hormones swing rather than fall in a straight line, so a good month can follow a bad one.4
This guide walks you through it in order: what the transition is and how to tell where you are, the signs that are easy to miss, what you can start this week, and when a doctor, and a coach, have a part to play.
Before the symptoms, it helps to know what perimenopause actually is, and how your own calendar can tell you which stage you have reached.
Perimenopause is the transition before your last period#
Perimenopause is the stretch between regular cycles and the final menstrual period, when the ovaries’ hormone output turns irregular. Menopause itself is only a single point in time: the moment twelve months have passed without a period.
In a large prospective study of more than 2,500 women, perimenopause began at a median age of 47.5 and lasted close to four years, and the final period came at a median age of 51.3.1 Those are medians: some women notice the first changes in their early forties, others not until their fifties, and smokers tend to start earlier and finish sooner.1
Clinicians now describe the transition in stages defined by what your cycle does, not by your age.2 That matters, because it means you can usually tell where you are from a calendar, without any test at all.
Menopause, in one sentence
The date of your final menstrual period, confirmed once twelve months have passed without one. Everything before it is perimenopause, everything after it is postmenopause.
Your cycle tells you which stage you are in#
The calendar does the work here. Cycles that keep varying by seven days or more mark the early transition, and gaps of sixty days or more mark the late transition, which usually lasts one to three years.2
| Stage | What your cycle does |
|---|---|
| Late reproductive years | Cycles are still regular. Flow or length may start to change subtly.2 |
| Early transition | The length of consecutive cycles differs by seven days or more, and it keeps happening.2 |
| Late transition | Sixty days or more without a period. This stage lasts one to three years on average, and hot flushes are most likely here.2 |
| Menopause | Twelve months after the final period. |
| Early postmenopause | The first years after. Hot flushes and night sweats often continue for several years.8 |
The pill, a hormonal coil or a hysterectomy hide the bleeding pattern. In those cases your symptoms become the main guide, and a conversation with your doctor matters more.9
Understand your perimenopause better
Fourteen short questions, and one of our experts reviews your case personally, then goes through it with you on a free call.
Knowing the stages is one thing. Recognising them in daily life is another, because the first signs rarely look like the menopause most people picture.
The first signs are rarely hot flushes#
What tends to come first is a change in your cycle, worse sleep, and shifts in mood or concentration, often months before the first hot flush. Many women simply notice that they no longer feel like themselves.
The first change in the cycle is often a shorter cycle rather than a missed one, sometimes with heavier or less predictable bleeding. Then the length starts to vary from one month to the next.2
Sleep often changes early. In the SWAN study, which followed more than 3,000 women through the transition, difficulty falling asleep and staying asleep became more common at each stage, and more frequent night sweats went with more disturbed nights.5
Mood is the sign most often missed. Among women who had never been depressed, high scores for depressive symptoms were more than four times as likely during the transition as before it, and the hormonal swings themselves were linked to the change.6 Anxiety and irritability rise in the same years.3
What it sounds like in everyday life#
Long before anyone mentions the menopause, the pattern tends to show up in a handful of everyday phrases. These are the ones we hear most often.
- I don’t feel like myself
- Waking at 3 a.m. and wide awake
- My periods are all over the place
- Anxiety out of nowhere
- Brain fog, I lose my words
- A much shorter fuse
- Heavier periods than before
- Night sweats
- Aching joints in the morning
- Less interest in sex
If some of these phrases sound familiar, it helps to understand why some months feel fine and others do not.
Hormones swing rather than fall in a straight line#
Estradiol swings from cycle to cycle, sometimes running higher than before, while progesterone tends to fall earlier.4 That uneven pattern is what makes one month feel normal and the next one not.
The familiar picture of “falling oestrogen” describes the years after menopause better than the years before it. During perimenopause, estradiol can run high in some cycles and low in others, and cycles without ovulation become more frequent.4
Progesterone, in one sentence
The hormone the ovary makes after ovulation. When ovulation becomes irregular, progesterone falls, often before estradiol does.
This is why a good month proves nothing and a bad month is not a verdict. It is also why a single hormone blood test, taken on one day, so often comes back normal.9
Over 45, you usually do not need a blood test#
Past 45, the transition is recognised from your symptoms and your cycle, and a blood test usually cannot confirm it.9 Testing matters when symptoms begin before 45, or to rule out other causes.
The UK’s national guideline advises diagnosing perimenopause in otherwise healthy women over 45 from their symptoms and cycle changes, and advises against FSH, estradiol or AMH tests for that purpose at that age, because the values move too much from one week to the next.9
Between 40 and 45, and under 40, testing does have a role: early menopause and premature ovarian insufficiency need a medical diagnosis and their own care.9 Your doctor may also want to rule out causes that look similar, such as a thyroid problem or iron deficiency.
FSH, in one sentence
Follicle-stimulating hormone, the signal from the pituitary that rises as the ovaries respond less. In perimenopause it can be high one week and normal the next.
Without a test to lean on, it helps to know which symptoms most often pass unnoticed.
This part looks at the signs that hide behind other explanations, and at how long the changes can last. Both are reasons to start helping yourself now rather than waiting.
Some signs are easily blamed on stress or age#
Poor sleep, low mood or anxiety, brain fog, aching joints, palpitations and a lower libido all have other possible causes. That is why, in these years, they are so often put down to something else.
Brain fog is real and measurable. In SWAN, women in perimenopause did not improve on repeated memory and processing-speed tests the way they did before the transition, and their performance returned to its earlier level after menopause.7 For most women, the fog lifts.
Later in the transition, vaginal dryness and pain during sex affect about a third of women. Unlike hot flushes, these do not resolve on their own, and they respond well to treatment, so they are worth raising with your gynaecologist.3
Hot flushes and night sweats can last for years#
Duration varies widely from one woman to the next, and frequent flushes and sweats often carry on for several years after the final period.8
In SWAN, frequent hot flushes or night sweats lasted 7.4 years in total at the median, and 4.5 years after the final period. Women whose flushes began while their cycles were still regular had the longest course, more than 11 years.8
That is not a reason for alarm. It is a reason to stop waiting it out: most symptoms respond to something, and the changes in memory and concentration appear to be temporary.7
Three free habits you can start this week#
Tracking your cycle and symptoms, protecting your sleep and strength training twice a week cost nothing, and all three can begin now. The first also makes every later conversation with a doctor more useful.
These habits help most women, but some symptoms should go to a doctor before anything else.
This last part sets out the warning signs, the treatments with real evidence behind them, and where our work sits.
Some signs need a doctor rather than a wait#
Very heavy bleeding, bleeding between periods or after sex, and any bleeding that returns after twelve months without a period belong with your doctor. So do symptoms that start before 40, and low mood that becomes hard to carry.
Hormone therapy is the most effective option for flushes#
Of the medical options, hormone therapy is the most effective for hot flushes and night sweats, and for most healthy women under 60 its benefits outweigh its risks.10 Cognitive behavioural therapy and non-hormonal medicines are options too.
The North American Menopause Society’s 2022 position statement concludes that hormone therapy remains the most effective treatment for hot flushes and night sweats and prevents bone loss, and that for women under 60, or within ten years of menopause, without contraindications, the balance of benefit and risk is favourable.10
The decision is individual: the type, the dose and the route all matter, and so does your own history. It is a conversation to have with your gynaecologist, and it is worth having early rather than after years of putting up with symptoms.10
Menopause-specific cognitive behavioural therapy is an option for hot flushes and for low mood, alongside hormones or instead of them.9 Vaginal dryness responds to low-dose local treatment.10
We work alongside your doctor, never instead#
Sleep, nutrition, muscle, stress and digestion all change how the transition feels, and they are what we work on with you, always beside your medical care and never in its place.
Medicine treats the symptoms of the transition well. What it rarely has time for is everything around them: sleep that was already fragile, blood sugar that now swings harder, a heavy stress load, the muscle you need to keep, the digestion that changed in the same years.
That is the work of our programmes and of the FunctionAlps Collective for women: a structured plan built on your own data, coordinated with your doctor when treatment is needed. Where it helps, a DUTCH test maps your hormone metabolites and your daily cortisol rhythm. It does not diagnose perimenopause, which needs no test over 45. It shows how your body is handling the change, so the plan fits you.
Quick answers12 questions this guide covers, in short
What is perimenopause, exactly?
Perimenopause is the transition between regular cycles and the final menstrual period, when the ovaries’ hormone output becomes irregular. Menopause itself is a single point in time: twelve months without a period. Read the section
How can you tell which stage of perimenopause you are in?
From your cycle. Cycles that keep varying by seven days or more mark the early transition, and gaps of sixty days or more mark the late transition, which usually lasts one to three years. Read the section
What are the first signs of perimenopause?
Usually a change in your cycle, worse sleep, and shifts in mood or concentration, often months before the first hot flush. Many women simply notice that they do not feel like themselves. Read the section
What do women in perimenopause say about themselves?
Long before anyone says the word menopause, the pattern shows up in a handful of phrases. These are the ones we hear most often. Read the section
Why do perimenopause symptoms come and go?
Because hormones do not fall in a straight line. Estradiol swings from cycle to cycle, sometimes higher than before, while progesterone tends to fall earlier, so some months feel normal and others do not. Read the section
Can a blood test confirm perimenopause?
Over 45, usually not, and you do not need one: perimenopause is recognised from your symptoms and your cycle. Blood tests matter when symptoms start before 45, or to rule out other causes. Read the section
Which perimenopause symptoms are easy to blame on something else?
Poor sleep, low mood or anxiety, brain fog, aching joints, palpitations and a lower libido. Each has other possible causes, which is why they are so often put down to stress or to age. Read the section
How long do perimenopause symptoms last?
It varies widely. In the largest study, frequent hot flushes and night sweats lasted 7.4 years at the median, and often continued for several years after the final period. Read the section
What can you start doing this week?
Track your cycle and symptoms, protect your sleep, and start strength training twice a week. All three are free, and the first makes every later conversation with a doctor more useful. Read the section
When should you see a doctor rather than wait?
When bleeding is very heavy, happens between periods or after sex, or returns after twelve months without a period, and whenever symptoms start before 40 or low mood becomes hard to carry. Read the section
What treatments actually help with perimenopause symptoms?
Hormone therapy is the most effective treatment for hot flushes and night sweats, and for most healthy women under 60 its benefits outweigh its risks. Cognitive behavioural therapy and non-hormonal medicines are options too. Read the section
Where does a functional approach fit in perimenopause?
Alongside medical care, never instead of it. Sleep, nutrition, muscle, stress and digestion all change how the transition feels, and they are what we work on with you. Read the section
- McKinlay SM, Brambilla DJ, Posner JG. The normal menopause transition. Maturitas. 1992;14(2):103-115. PMID : 1565019. Link
- Harlow SD, Gass M, Hall JE, et al. Executive summary of the Stages of Reproductive Aging Workshop + 10: addressing the unfinished agenda of staging reproductive aging. Menopause. 2012;19(4):387-395. PMID : 22343510. Link
- Santoro N. Perimenopause: from research to practice. J Womens Health (Larchmt). 2016;25(4):332-339. PMID : 26653408. Link
- Prior JC. Perimenopause: the complex endocrinology of the menopausal transition. Endocr Rev. 1998;19(4):397-428. PMID : 9715373. Link
- Kravitz HM, Zhao X, Bromberger JT, et al. Sleep disturbance during the menopausal transition in a multi-ethnic community sample of women. Sleep. 2008;31(7):979-990. PMID : 18652093. Link
- Freeman EW, Sammel MD, Lin H, Nelson DB. Associations of hormones and menopausal status with depressed mood in women with no history of depression. Arch Gen Psychiatry. 2006;63(4):375-382. PMID : 16585466. Link
- Greendale GA, Huang MH, Wight RG, et al. Effects of the menopause transition and hormone use on cognitive performance in midlife women. Neurology. 2009;72(21):1850-1857. PMID : 19470968. Link
- Avis NE, Crawford SL, Greendale G, et al. Duration of menopausal vasomotor symptoms over the menopause transition. JAMA Intern Med. 2015;175(4):531-539. PMID : 25686030. Link
- National Institute for Health and Care Excellence. Menopause: identification and management. NICE guideline NG23. London: NICE; 2015, last updated 15 April 2026. Link
- The 2022 Hormone Therapy Position Statement of The North American Menopause Society Advisory Panel. The 2022 hormone therapy position statement of The North American Menopause Society. Menopause. 2022;29(7):767-794. PMID : 35797481. Link
- Finkelstein JS, Brockwell SE, Mehta V, et al. Bone mineral density changes during the menopause transition in a multiethnic cohort of women. J Clin Endocrinol Metab. 2008;93(3):861-868. PMID : 18160467. Link
- Watson SL, Weeks BK, Weis LJ, et al. High-intensity resistance and impact training improves bone mineral density and physical function in postmenopausal women with osteopenia and osteoporosis: the LIFTMOR randomized controlled trial. J Bone Miner Res. 2018;33(2):211-220. PMID : 28975661. Link
Articles published by FunctionAlps are educational and written within ASCA and EMR scope. They do not replace personalised clinical advice. When findings warrant medical evaluation, we coordinate with a referring physician.