If you've started to feel slightly off — and your doctor's tests came back "normal" — you are not imagining it, and you are not alone.
Perimenopause is the transition leading up to menopause, and it can last anywhere from a couple of years to a decade. The word simply means "around menopause." During this time your ovaries don't switch off neatly; they sputter. Oestrogen and progesterone rise and fall less predictably than they used to, and it's that fluctuation — not a steady decline — that drives most early symptoms.
Here are the first signs women most often miss:
Your cycle changes character. This is usually the earliest clue. Periods may come closer together or further apart, become heavier or lighter, or simply lose their old rhythm. A cycle that was always 28 days might start arriving at 24, then 31.
Sleep gets lighter. You fall asleep fine but wake at 3 a.m. with your mind racing. Progesterone — a naturally calming, sleep-supporting hormone — is often the first to dip, and your rest is frequently the first thing to suffer.
Your mood feels less steady. Irritability, anxiety, or tearfulness that seem out of proportion are common. This isn't a character flaw; shifting oestrogen directly affects the brain chemicals that regulate mood.
Energy and focus dip. The "brain fog" so many women describe — losing a word mid-sentence, walking into a room and forgetting why — is real and well documented during this transition.
Other early signals include new tension headaches, breast tenderness, a shorter fuse, and changes in libido.
The reassuring part: these shifts are a normal, expected stage of life, not a sign that something is broken. The frustrating part is how often they're brushed aside. Standard blood tests can look "normal" in perimenopause precisely because your hormones are fluctuating — a single snapshot may catch a good day.
If several of these signs sound familiar, it's worth tracking them — your cycle, your sleep, your mood — over a few months, and bringing that record to a clinician who takes the menopause transition seriously. You know your body better than any one-off test does.
What age does perimenopause usually start?
For most women it begins in the early-to-mid 40s, though it can start in the late 30s.
Can you be in perimenopause and still have regular periods?
Yes — early on, your cycle often changes subtly before it becomes clearly irregular.
Keep reading: How hormones hijack your sleep · How long do menopause symptoms last? · Take the free Hormone Quiz