Perimenopause: Symptoms, Age, Stages and Hormone Tests

Perimenopause is the transition before menopause, when the ovaries slow down and oestrogen and progesterone rise and fall unpredictably. It usually starts in the mid-40s, lasts about four years on average, and ends 12 months after your last period. The first sign is usually a change in your cycle: earlier, later, heavier, lighter or skipped periods.

Hot flushes, night sweats, poor sleep, mood changes and brain fog are common. Doctors diagnose perimenopause from your age, symptoms and cycle pattern, not from one hormone test, because FSH and oestradiol swing from week to week. Blood tests still help when symptoms start early, when bleeding is heavy, or to rule out thyroid disease or pregnancy.

Key takeaways

• Perimenopause usually begins in the mid-40s and lasts about four years on average.
• Early perimenopause: cycle lengths differ by 7 days or more; late perimenopause: gaps of 60 days or more.
• FSH and oestradiol often mislead; tests help most before 45, for heavy bleeding and to exclude thyroid disease, high prolactin or pregnancy.
• You can still get pregnant, so keep using contraception until your clinician says you can stop.
• Options include hormone therapy, the low-dose contraceptive pill, nonhormonal medicines and cognitive behavioural therapy (CBT).

What is perimenopause?

Perimenopause means "around menopause": the ovaries gradually run out of eggs and their hormone output becomes erratic. For the years before and after the final period as a whole, see our guide to menopause symptoms, stages and treatment; this article focuses on the transition itself.

Hormones do not fall in a straight line. The STRAW+10 consensus describes "extreme fluctuations" in the late transition, with FSH sometimes in the menopausal range and sometimes back to younger values. That roller coaster explains why symptoms come and go and why one blood test rarely tells the whole story.

Perimenopause vs menopause

• Perimenopause is a process: you still have periods, even irregular ones, and can still ovulate and get pregnant.
• Menopause is a point in time: 12 consecutive months without a period. The average age in the United States is 52, according to the Office on Women's Health (OWH). The NHS says menopause usually affects women between 45 and 55.
• Postmenopause is everything after that point.

In STRAW+10, perimenopause starts with the early menopausal transition and ends 12 months after the final period.

Perimenopause age: when does it start and how long does it last?

According to Cleveland Clinic, perimenopause begins about eight to 10 years before menopause, usually in the mid-40s, but it can start in the mid-30s or as late as the mid-50s. It lasts about four years on average and up to eight years; OWH says up to 10. Smoking brings menopause forward by about one to two years.

Menopause completed before 40 is called premature menopause; without a medical or surgical cause, it is primary ovarian insufficiency (POI). The 2024 guideline of the European Society of Human Reproduction and Embryology (ESHRE) estimates that POI affects about 3.5% of women.

Stages of perimenopause (STRAW+10)

STRAW+10 (Stages of Reproductive Ageing Workshop, 2012) is the reference staging system. It relies mainly on your bleeding pattern, which you can track with a calendar or app.

Hot flushes are most likely in late perimenopause and the first two years after the last period.

Perimenopause symptoms and signs

Some people notice only skipped periods; others have many disruptive symptoms. Cleveland Clinic and the American College of Obstetricians and Gynecologists (ACOG) list these common signs of perimenopause:

• irregular or skipped periods, heavier or lighter flow, worse PMS;
• hot flushes and night sweats;
• trouble falling asleep or waking too early;
• irritability, low mood, anxiety or mood swings;
• vaginal dryness, pain during sex, urinary urgency or more urinary infections;
• lower sex drive.

Less classic complaints include bloating, joint aches and queasiness (see perimenopause nausea). Online lists of "34 symptoms of perimenopause" are not an official medical list, and many items have other causes worth checking.

Early signs of perimenopause

The earliest sign is usually a change in cycle length: slightly shorter cycles first, then cycles that vary by a week or more. For NICE (the UK's National Institute for Health and Care Excellence), new hot flushes plus any cycle change are enough to identify perimenopause in a healthy woman aged 45 or over.

Hot flushes and night sweats

In the US Study of Women's Health Across the Nation (SWAN), frequent hot flushes or night sweats lasted a median of 7.4 years. Women whose hot flushes began while premenopausal or in early perimenopause had them longest, more than 11.8 years at the median.

Mood, anxiety and sleep

A 2024 meta-analysis found about 40% higher odds of depressive symptoms or depression in perimenopausal than in premenopausal women (odds ratio 1.40), with no significant increase after menopause. A 2026 meta-analysis of 102 studies estimated that about 32% of perimenopausal women have depressive symptoms and 27% insomnia symptoms at any given time. Most women with a major depressive episode in perimenopause have had one before. If low mood lasts more than two weeks, read about depression symptoms and diagnosis and talk to a clinician.

Brain fog and memory

In SWAN, perimenopausal women did not improve on repeated memory and processing-speed tests as premenopausal women did, and performance rebounded after menopause. A 2026 neurology review adds that these complaints are usually transient and that poor sleep, hot flushes and mood play a part.

Weight gain and body shape

SWAN measured body composition with DXA scans: at the start of the transition, the rate of fat gain doubled and lean mass began to fall, until about two years after the last period. Weight itself did not climb faster. The change is mostly in body composition and belly fat.

What causes perimenopause symptoms?

As the egg supply shrinks, the pituitary gland releases more FSH to push the ovaries. Some cycles then produce very high oestradiol; others skip ovulation and make little progesterone. ACOG notes that irregular ovulation, common in perimenopause, can make the uterine lining too thick and cause heavy bleeding. Low oestrogen triggers hot flushes through brain cells that regulate body temperature, the target of the newer nonhormonal medicines.

Heavy bleeding: what is normal and what is a red flag

Changes in flow are normal, but ACOG advises reporting them. It defines heavy menstrual bleeding as bleeding that lasts more than 7 days, soaks one or more pads or tampons every hour for several hours, or contains clots as big as a quarter. Cleveland Clinic also advises a visit if periods last several days longer than usual, come less than 21 days apart, or if you bleed between periods or after sex.

Causes to rule out include fibroids, polyps, infection, clotting disorders and cancer. Heavy periods can also lead to iron-deficiency anaemia; a complete blood count and a ferritin test show whether this is happening.

Do you need a perimenopause blood test?

Usually not for the diagnosis. NICE advises identifying perimenopause without laboratory tests in healthy people aged 45 or over with recent hot flushes and cycle changes, and advises against using AMH, inhibin, oestradiol, antral follicle count or ovarian volume for that purpose. MedlinePlus notes that FSH testing is usually unnecessary from 45, and Cleveland Clinic that hormones "fluctuate so much that the tests aren't reliable".

FSH levels in perimenopause

FSH rises erratically: a high value one month can be followed by a normal one the next. STRAW+10 considers a random FSH above 25 IU/L typical of late perimenopause. A normal result does not rule out perimenopause, and contraceptive pills make FSH uninterpretable. See our FSH levels test guide.

Oestradiol

Oestradiol, the main ovarian oestrogen, can be high, normal or low depending on the day, so one value says little about your stage. Read more about oestradiol levels.

When tests do help

• Under 40: NICE diagnoses POI from symptoms plus a raised FSH on two samples 4 to 6 weeks apart; the 2024 ESHRE guideline accepts a single FSH above 25 IU/L, with a repeat FSH or AMH if unclear.
• Between 40 and 45: NICE says an FSH test can be considered.
• Thyroid disease can mimic perimenopause; a TSH blood test sorts this out.
• Missed periods with breast discharge or headaches call for a prolactin test (see high prolactin levels).
• A skipped period at 44 can still be a pregnancy: an hCG test answers that.
• Heavy bleeding: a blood count and ferritin look for iron deficiency.
• Midlife heart and metabolic check: a lipid panel and an HbA1c test.

Perimenopause blood test results at a glance

General reference values from MedlinePlus (STRAW+10 for the FSH threshold). Ranges vary between laboratories: compare with the range on your own report. Under 40, a high FSH deserves a repeat test and a specialist opinion.

Perimenopause treatment

Treatment depends on your main symptoms, health history and need for contraception. Cleveland Clinic notes that many people with mild symptoms do well with lifestyle changes alone.

Low-dose contraceptive pill and hormonal IUD

Because you still ovulate, low-dose contraceptive pills often fit well: Cleveland Clinic explains that they stabilize hormone levels and usually relieve symptoms. A levonorgestrel IUD (Mirena) can control heavy or irregular bleeding and later serve as the progestogen part of hormone therapy.

Menopausal hormone therapy (MHT)

The Menopause Society's 2022 position statement calls hormone therapy the most effective treatment for hot flushes and genitourinary symptoms, and says it prevents bone loss and fractures. For women under 60 or within 10 years of menopause onset without contraindications, the benefit-risk balance is favourable. People with a uterus need a progestogen with oestrogen. A 2026 neurology review notes that transdermal oestradiol (patch or gel) seems safer than oral oestrogen regarding clots and stroke. ACOG adds that hormone therapy can help heavy perimenopausal bleeding.

Nonhormonal medicines for hot flushes

The Menopause Society's 2023 nonhormone statement recommends CBT, clinical hypnosis, low-dose SSRIs and SNRIs, gabapentin and fezolinetant (strongest evidence), and oxybutynin. Fezolinetant (Veozah) blocks the neurokinin 3 receptor and was approved by the FDA on May 12, 2023; elinzanetant (Lynkuet), which blocks neurokinin 1 and 3 receptors, on October 24, 2025. Both are approved for moderate to severe hot flushes "due to menopause", and their pivotal trials enrolled only postmenopausal women (SKYLIGHT 1 required 12 months without a period, or 6 months with FSH above 40 IU/L), so evidence while periods continue is limited. Fezolinetant carries a boxed warning for rare but serious liver injury, with liver tests before starting, monthly for three months, then at months 6 and 9.

Vaginal oestrogen

For vaginal dryness or pain during sex not relieved by products bought without a prescription, the 2022 statement recommends low-dose vaginal oestrogen, vaginal DHEA or oral ospemifene.

CBT, sleep and mood care

The 2024 NICE update recommends considering menopause-specific CBT for hot flushes, related sleep problems and depressive symptoms. For diagnosed depression, antidepressants and psychotherapy remain first line; oestrogen may have antidepressant effects in perimenopausal women with hot flushes, but it is not approved for that use.

Perimenopause supplements

The Menopause Society does not recommend supplements or herbal remedies for hot flushes, nor soy products, cannabinoids or acupuncture. NICE notes some evidence for isoflavones and black cohosh but warns that products vary, safety is uncertain and interactions occur.

Protect your bones and heart during perimenopause

An American Heart Association scientific statement describes adverse changes in body composition, lipids and blood vessels across the menopause transition and calls midlife a critical window for prevention; MedlinePlus notes that cholesterol risk rises after menopause. For glucose, see menopause and blood sugar. In SWAN, even modest increases in leisure-time activity, mostly walking, were linked to slower hip bone loss, and losing lean mass during the transition was linked to more fractures later. Strength training, enough protein, calcium and vitamin D, and not smoking all help; a calcium and bone panel can join the check-up.

Contraception in perimenopause

You can still get pregnant during perimenopause, even if you skip periods. OWH and Cleveland Clinic advise using contraception until your clinician says it is safe to stop; assume you still ovulate until 12 months without a period. Hormone therapy is not a contraceptive.

When to see a doctor

See a clinician if symptoms disrupt your sleep, work or relationships, if periods change before 40, or if you have:

• bleeding that soaks a pad or tampon every hour for several hours, lasts more than 7 days or has large clots;
• bleeding between periods, after sex, or periods less than 21 days apart;
• any bleeding after 12 months without a period;
• tiredness, breathlessness or dizziness that could signal anaemia.

Call 999 for very heavy bleeding with fainting or a racing heart, chest pain, a sudden severe headache or signs of stroke. For thoughts of self-harm, call Samaritans free on 116 123.

Latest scientific advances in perimenopause

A second nonhormonal pill for hot flushes

In the OASIS 1 and 2 trials (JAMA, 2024; NCT05042362 and NCT05099159), about 800 postmenopausal women aged 40 to 65 took elinzanetant 120 mg or placebo. At 12 weeks, elinzanetant reduced daily hot flushes by about three more than placebo and improved sleep and quality of life. A 2026 pooled analysis of 1,519 women found headache, fatigue and sleepiness as the most common side effects, without serious liver injury signals. It has not been tested in women who still menstruate.

The FDA rewrites hormone therapy warnings

On November 10, 2025, the FDA announced the removal of boxed warnings on cardiovascular disease, breast cancer and probable dementia from menopausal hormone therapy labels, keeping the endometrial cancer warning for systemic oestrogen-alone products. Labels will recommend starting systemic therapy within 10 years of menopause onset or before 60. Your personal risks still guide the decision.

Mood is now a screening priority

The 2024 meta-analysis (about 40% higher odds of depression in perimenopause) and the 2026 analysis of more than one million women (depressive symptoms in about one in three perimenopausal women) both call for routine mental health screening during the transition.

Simpler diagnosis of early ovarian insufficiency

The 2024 ESHRE guideline, developed with the American Society for Reproductive Medicine and the International Menopause Society, needs only one FSH above 25 IU/L, with symptoms, to diagnose POI before 40, and clarifies when AMH helps.

Trials testing lifestyle and supplements

Northumbria University is testing magnesium (NCT07235878) and a multivitamin (NCT07242430) against placebo on perimenopause symptoms, sleep and cognition; the University of British Columbia, resistance training for memory complaints (NCT07272174); Penn State, prunes against perimenopausal bone loss (NCT07120997). Results are not yet published.

Which tests can help?

There is no single perimenopause test, but a smart set of blood tests rules out look-alikes and protects long-term health: TSH, prolactin and hCG when periods change; a blood count and ferritin when bleeding is heavy; FSH, sometimes AMH, when symptoms start before 45; a lipid panel, HbA1c and, if relevant, vitamin D and calcium. If TSH is high, our guide to hypothyroidism explains next steps. Bring your cycle diary: it often says more than any single hormone value.

Glossary

• Perimenopause: the transition to menopause.
• FSH: follicle-stimulating hormone, from the pituitary; it rises as the ovaries slow down.
• Oestradiol: the main oestrogen made by the ovaries.
• AMH: anti-Müllerian hormone, a marker of egg supply.
• STRAW+10: the international staging system for reproductive ageing.
• Vasomotor symptoms: hot flushes and night sweats.
• POI: primary ovarian insufficiency, ovarian failure before 40.

Frequently asked questions

What are the early signs of perimenopause?

Cycles that become shorter, longer or more variable, heavier or lighter periods, worse PMS, new hot flushes or night sweats, and poor sleep. Mood changes and lower sex drive are also common.

What is the earliest age for perimenopause?

It can start in the mid-30s, though the mid-40s is typical. If periods stop or menopausal symptoms appear before 40, see a clinician: primary ovarian insufficiency needs testing and usually treatment.

Are these symptoms of perimenopause at 44?

Irregular periods with hot flushes at 44 are very often perimenopause. Because you are under 45, a clinician may still check FSH, TSH, prolactin and a pregnancy test before confirming it.

Which is worse, perimenopause or menopause?

It depends on the symptom. Hot flushes peak in late perimenopause and the first years after the last period; depression risk rises in perimenopause; irregular, heavy bleeding belongs to perimenopause; vaginal dryness tends to worsen after menopause without treatment.

Can high cortisol contribute to weight gain in perimenopause?

A Seattle study found that overnight cortisol rises in some women in the late transition, but the belly fat gain of perimenopause is mainly the body composition shift seen in SWAN. Truly high cortisol, as in Cushing syndrome, adds trunk fat with thinner arms and legs and purple stretch marks; if you notice these, ask about high cortisol testing.

What is the best perimenopause treatment?

There is no single best option. Hormone therapy works best for hot flushes; low-dose contraceptive pills suit those who need contraception or have irregular bleeding; SSRIs, SNRIs, gabapentin, fezolinetant, elinzanetant and CBT are alternatives; vaginal oestrogen treats dryness.

Sources

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• The North American Menopause Society — The 2022 hormone therapy position statement — Menopause, 2022 — doi.org
• The North American Menopause Society — The 2023 nonhormone therapy position statement — Menopause, 2023 — doi.org
• Lederman S et al. — Fezolinetant for vasomotor symptoms (SKYLIGHT 1) — Lancet, 2023 — doi.org
• Pinkerton JV et al. — Elinzanetant for vasomotor symptoms: OASIS 1 and 2 — JAMA, 2024 — doi.org
• Pinkerton JV et al. — Safety of elinzanetant: pooled analysis of four trials — EClinicalMedicine, 2026 — doi.org
• Avis NE et al. — Duration of menopausal vasomotor symptoms — JAMA Intern Med, 2015 — doi.org
• Badawy Y et al. — Risk of depression in the menopausal stages: meta-analysis — J Affect Disord, 2024 — doi.org
• Balasubramanian I et al. — Depressive, anxiety and insomnia symptoms around menopause: meta-analysis — Gen Hosp Psychiatry, 2026 — doi.org
• Maki PM et al. — Guidelines on perimenopausal depression — J Womens Health, 2019 — doi.org
• Greendale GA et al. — Menopause transition and cognitive performance — Neurology, 2009 — doi.org
• Thornton HF et al. — Menopause and Neurology: Clinical Essentials — Neurol Clin Pract, 2026 — doi.org
• Greendale GA et al. — Body composition and weight during the menopause transition — JCI Insight, 2019 — pubmed.ncbi.nlm.nih.gov
• Woods NF et al. — Cortisol levels during the menopausal transition — Menopause, 2009 — doi.org
• El Khoudary SR et al. — Menopause transition and cardiovascular disease risk (AHA statement) — Circulation, 2020 — doi.org
• Greendale GA et al. — Physical activity and bone density in the menopause transition (SWAN) — Lancet Reg Health Am, 2023 — doi.org
• Shieh A et al. — Menopause-related body composition changes and fractures — J Bone Miner Res, 2023 — doi.org
• Panay N et al. — Evidence-based guideline: premature ovarian insufficiency (ESHRE) — Hum Reprod Open, 2024 — doi.org
• Northumbria University — Magnesium supplementation on perimenopause symptoms (NCT07235878) — ClinicalTrials.gov — clinicaltrials.gov
• Northumbria University — Multivitamin/mineral supplementation on perimenopause symptoms (NCT07242430) — ClinicalTrials.gov — clinicaltrials.gov
• University of British Columbia — Resistance training and cognitive health in perimenopause (NCT07272174) — ClinicalTrials.gov — clinicaltrials.gov
• Penn State University — Prunes and perimenopausal bone loss (NCT07120997) — ClinicalTrials.gov — clinicaltrials.gov
• NICE — Menopause: identification and management (NG23), recommendations — 2024 — nice.org.uk
• FDA — Approval of Veozah (fezolinetant) — FDA, 2023 — fda.gov
• FDA — Liver injury warning for Veozah — FDA, 2024 — fda.gov
• FDA — Removal of boxed warnings on hormone therapy — FDA, 2025 — fda.gov
• FDA — Novel Drug Approvals for 2025 (Lynkuet) — fda.gov
• Cleveland Clinic — Perimenopause: Age, Stages, Signs, Symptoms and Treatment — clevelandclinic.org
• Office on Women's Health — Menopause basics — womenshealth.gov
• ACOG — The Menopause Years — acog.org
• ACOG — Heavy Menstrual Bleeding — acog.org
• MedlinePlus — FSH Levels Test — medlineplus.gov
• MedlinePlus — Follicle stimulating hormone (FSH) blood test — medlineplus.gov
• MedlinePlus — Oestradiol blood test — medlineplus.gov
• MedlinePlus — Anti-Müllerian Hormone Test — medlineplus.gov
• MedlinePlus — TSH test — medlineplus.gov
• MedlinePlus — Ferritin blood test — medlineplus.gov
• MedlinePlus — Prolactin blood test — medlineplus.gov
• MedlinePlus — Cholesterol Levels: What You Need to Know — medlineplus.gov
• MedlinePlus — Hemoglobin A1C Test — medlineplus.gov
• MedlinePlus — Cushing syndrome — medlineplus.gov
• NHS — Menopause and perimenopause — National Health Service (England) — nhs.uk

Further reading

• Female hormone panel: what your results mean
• LH blood test: how to read your results
• Fertility blood test: hormones to check
• Low testosterone in women: symptoms and testing
• Ferritin levels in women: new ASH cutoffs
• 25-OH vitamin D blood test: read your results
• Sleep apnea: symptoms, tests and treatment

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