Straight answers

You're losing your words, and no, you're not losing your mind

By the Maia team 28 July 2026 7 min read With sources from SWAN and Neurology

You're mid-sentence and the word won't come. It's on the tip of your tongue, you use it every day, and there it stays. You walk into a room and can't think what you came for. You read the same paragraph three times. And at some point comes the thought that's frightening to say out loud: is something happening to my brain? Let's look at what the evidence actually says.

In short

It's very common across the menopause transition, and almost always mild.
It's real and measurable: you aren't imagining it.
Poor sleep and anxiety make it much worse — which is where most can be done.
Only 11 to 13% of women reach clinically significant impairment.
In the SWAN study, the perimenopausal dip recovered after menopause.
There are specific signs that do warrant a doctor. They're below.

What brain fog actually is

"Brain fog" isn't a medical diagnosis. It's the name we give to something very recognisable: losing words, losing the thread of a conversation, struggling to concentrate, everyday memory slipping more than it used to.

It's common, and well documented. The International Menopause Society white paper on cognition and menopause confirms these complaints show up consistently right across the transition. Most women notice it first at work, which is where it stings most: going blank in a meeting, having to write everything down, feeling you're not as sharp as you were.

That same paper adds the half that rarely gets quoted: for the great majority of women these symptoms stay mild, and everyday function holds up. Only 11 to 13% reach clinically significant impairment.

It's also the symptom people keep quietest about. You can mention a hot flush. You can't mention forgetting the name of someone you've worked with for ten years.

What the science says: it's real, and it's temporary

This is the part worth reading slowly, because it changes the whole frame.

For years these lapses were written off as subjective — stress, or suggestion. The SWAN study, which has followed thousands of women through the transition, showed otherwise. In a study published in Neurology, women in perimenopause showed a measurable drop in processing speed and verbal memory. Not a feeling: it showed up on testing.

And the same study found the part almost nobody reports: that drop resolved after menopause. During perimenopause performance plateaus; once the transition is behind you, it picks up again.

Perimenopause was associated with a transient decrement in processing speed and verbal memory, which resolved in postmenopause. Greendale et al., Neurology (2009), SWAN study

Put plainly: this is a phase, not a loss. Your brain is going through a hormonal shift, not deteriorating.

Why it happens

Oestrogen doesn't only act on the reproductive system. There are oestrogen receptors in the hippocampus and the prefrontal cortex — exactly the regions involved in memory and attention. When levels start swinging irregularly, which is what perimenopause is, those regions feel it.

Two things make it worse, and they matter because you can do something about both:

Sleep. Memory consolidates while you sleep. If you're waking at 3am, your cognitive performance the next day drops — that would happen to anyone, at any age. For a lot of women, the "fog" turns out to be largely accumulated sleep debt.
Anxiety and low mood. The SWAN researchers found that anxiety and depressive symptoms had a negative effect on processing speed. When your head is busy worrying, there's less capacity left for everything else.

And there's a cruel loop in it: you lose a word, it frightens you, you tense up — and the tension makes the next one harder still.

"What if it's dementia?"

It's the question almost everyone asks themselves and almost nobody says out loud. It deserves a straight answer.

Perimenopausal forgetting has a fairly distinctive shape: it mostly affects finding words and concentrating, it comes and goes — good days and bad days — it's clearly worse after a bad night, and it doesn't stop you getting on with your life. You know you've forgotten something, and that difference matters.

That said, there are signs a doctor should look at — not to frighten you, but to put the question properly to rest.

When to see a doctor

The forgetting is progressive and constant, not fluctuating.
It affects tasks you used to do easily: driving somewhere familiar, managing money, following a recipe you know.
You get disoriented in places or situations you know well.
Other people notice before you do.
There are changes in personality or behaviour.
It comes with other neurological symptoms: difficulty speaking or walking, or changes in vision.

Either way, it's worth asking your doctor to rule out other treatable causes that also cause fog: hypothyroidism, anaemia, vitamin B12 or D deficiency, sleep apnoea and medication effects.

What helps

The first thing that helps — and this isn't empty reassurance — is simply knowing what it is. Most of the distress here comes not from the forgetting but from the fear attached to it. Naming it brings the anxiety down, and bringing anxiety down improves cognition directly.

Then go after what sits underneath it. Sleep is the biggest lever: fix the 3am waking and the fog usually lifts a fair way. Regular exercise — aerobic especially — has a demonstrated effect on memory and attention. And the practical fixes help more than you'd think: write everything down without guilt, stop trying to do three things at once, and save the demanding work for your good hours.

Beyond that, there are treatments for the symptoms of the transition, set out in clinical guidelines such as NICE NG23. By improving sleep and easing hot flushes, they tend to help your head too. What fits you is a conversation with a professional who knows this stage.

This is exactly what Maia does. The hard part is almost never a single symptom: it's that the brain fog, the 3am waking, the exhaustion and the anxiety look like unrelated things — and that makes the pattern impossible to see. Maia joins the dots so you can see the whole picture and understand what's happening to you.

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Frequently asked questions

Is perimenopause brain fog permanent?

The available evidence says no. In the SWAN study, the dip in processing speed and verbal memory seen during perimenopause resolved after menopause. So it's real and measurable, but it's also transient.

Is it brain fog or something more serious?

Brain fog at this stage mostly affects word-finding and concentration, it comes and goes, it's worse after a bad night, and it doesn't stop you functioning. It's worth seeing a doctor if the forgetting is progressive and constant, if it affects tasks you used to do easily, if you get lost in familiar places, or if other people notice before you do.

At what age does perimenopause brain fog start?

It usually appears between 40 and 50, within perimenopause, and often before hot flushes. Many women notice it first at work: losing the thread in a meeting, or not finding a word they use every day.

Can anything be done about brain fog?

Yes. What helps most is usually treating what sits underneath it: sleep and anxiety, both of which markedly worsen cognitive performance. Regular exercise has a demonstrated effect too. And there are treatments for the symptoms of the transition worth discussing with a professional.

Keep reading: the full guide to perimenopause — what it is, when it starts and every symptom — or why you're so tired even when you sleep.

Maia isn't a medical service and doesn't replace your healthcare professional. This article is informational and isn't a diagnostic tool: if your memory worries you, talk to your doctor.

Sources: Greendale et al., "Effects of the menopause transition and hormone use on cognitive performance in midlife women", Neurology (2009), SWAN study; Greendale et al., "Menopause-associated Symptoms and Cognitive Performance", American Journal of Epidemiology (2010); SWAN, "Memory and Cognition During and After the Menopause Transition" fact sheet; on how common and how severe cognitive complaints are — including the 11-13% figure — Maki PM and Jaff NG, "Brain fog in menopause: a health-care professional's guide for decision-making and counseling on cognition", Climacteric 25(6):570-578 (2022), an International Menopause Society white paper; NHS, "Menopause and perimenopause"; NICE, guideline NG23 (2024 update).