Perimenopause: Symptoms, Diagnosis and When HRT Can Help

How to recognise perimenopause, why blood tests often mislead, when HRT can help, and why you still need contraception.

Part of the Complete Hormone Replacement Therapy Guide.

Perimenopause — the transition years before your final period — is when most menopausal symptoms actually begin, often while you're still having periods. It typically starts in the mid-40s but can begin in the late 30s, and lasts 4–8 years. Because hormone levels fluctuate rather than simply fall, symptoms can be confusing, intermittent and easy to misattribute to stress, depression or "just being busy". You do not need to wait until your periods stop to get treatment.

Common perimenopause symptoms

• Changes to your cycle — shorter, longer, heavier, lighter or unpredictable periods (usually the first sign)
• Hot flushes and night sweats, often mild at first
• New or worsening anxiety, irritability or low mood, often premenstrually
• Broken sleep, even without night sweats
• Brain fog — word-finding difficulty, poor concentration
• Worsening PMS or migraine
• Vaginal dryness, reduced libido
• Joint aches, heart palpitations, itchy or dry skin

Symptoms fluctuate because oestrogen does — you can feel normal for weeks, then symptomatic again. That pattern is itself a clue.

How perimenopause is diagnosed

For women over 45 with typical symptoms, NICE guidance says perimenopause should be diagnosed clinically — no blood test is needed. FSH and oestrogen levels swing so much during perimenopause that a single normal result can't rule it out. Blood tests (FSH) are only recommended for women aged 40–45 with symptoms, or under 40 where premature ovarian insufficiency is suspected — that affects around 1 in 100 women and needs prompt specialist assessment.

Can you take HRT during perimenopause?

Yes — and starting during perimenopause is common and often the ideal time. Because you're still having (some) periods, the usual regimen is cyclical (sequential) combined HRT: oestrogen every day, plus progestogen for 12–14 days of each cycle, giving a predictable monthly bleed. Once you're 12+ months past your last period, you'd switch to continuous combined HRT. Women who've had a hysterectomy take oestrogen alone.

Transdermal oestrogen (a patch like Evorel or gel like Oestrogel) is often preferred — no increased blood-clot risk, easy dose adjustment as your own hormones decline. An alternative for the progestogen component is the Mirena coil, which also solves the next problem.

You still need contraception

Perimenopausal women can and do conceive. HRT is not a contraceptive. You need contraception until 2 years after your last natural period if you're under 50, or 1 year after if you're over 50. The Mirena IUS, progestogen-only pill and barrier methods are all compatible with HRT.

When to seek help

Don't wait for a "bad enough" threshold — if symptoms affect your quality of life, sleep, work or relationships, that justifies treatment under NICE guidance. Seek assessment promptly for menopausal symptoms before 40, very heavy or prolonged bleeding, or bleeding between periods or after sex (these need investigation, not assumption).

If you think you might be perimenopausal, Access Doctor's pharmacist independent prescribers can assess your symptoms through a confidential online consultation and, where appropriate, prescribe the right HRT with discreet next-day delivery.