Draft · 8 min read

The misdiagnosis problem

Why cognitive symptoms in the transition are so often labelled anxiety.


A woman in her mid-forties tells her doctor she can't find words, that she rereads the same paragraph three times, that she feels unlike herself in a way she can't articulate. She leaves with a conversation about anxiety, sometimes a prescription for it. This sequence is common enough to have a shape — and the research literature explains why it keeps happening.

The first reason is that perimenopause rarely announces itself the way menopause does. There may be no hot flushes yet. Cycles may still be roughly regular. The presenting complaint is cognitive, and cognitive complaints in midlife women have a well-worn diagnostic shortcut: stress, anxiety, depression.

The second reason is that anxiety and brain fog genuinely co-occur — but the direction of the arrow is often assumed rather than examined. The study that separates them most cleanly is Weber, Rubin and Maki (Menopause, 2013): verbal learning and memory performance was lowest in the early perimenopausal stage, and the effect held independent of depressive symptoms and sleep complaints. The cognitive change was not a downstream symptom of mood. It stood on its own.

That finding matters clinically, because treating the wrong target wastes the window. If the cognitive complaint is attributed to anxiety, the intervention aims at mood — while the hormonal transition underneath goes unaddressed and the woman leaves with the sense, again, that she wasn't quite heard.

None of this means mood symptoms aren't real or don't deserve care. They are, and they do. It means the differential is incomplete when perimenopause isn't on it. A woman presenting with new cognitive difficulty in her forties, with any irregularity in her cycle, should have the transition considered as a first-line explanation — not a diagnosis of exclusion after everything else has been tried.

There is also a self-advocacy angle here. Bringing specifics helps: when it started, which tasks are harder, whether it fluctuates. The Maki and Jaff clinical review (Climacteric, 2022) was written precisely to give clinicians a reference for this presentation — cognitive complaints without vasomotor symptoms. It exists because the pattern needed naming.

If you've had this experience — the complaint heard, the wrong conclusion reached — the research is on your side. The cognitive change of perimenopause is documented, it is independent of mood, and it deserves an answer aimed at the right cause.

Common questions

Brain fog, answered clinically.

Does perimenopause cause brain fog?

Yes — cognitive change is one of the most commonly reported experiences of the perimenopausal transition, and it is not imagined. Women describe it as word-finding difficulty, losing the thread mid-sentence, and recall that has become effortful rather than automatic.

The mechanism is hormonal rather than degenerative. Estrogen fluctuates erratically before it declines, and estrogen receptors are densely distributed in the hippocampus and prefrontal cortex — the regions that handle verbal memory and executive function. Sleep disruption and cortisol dysregulation during the same window compound the effect. Longitudinal research on midlife women has repeatedly found measurable changes in verbal memory across the transition, with most women returning to their own baseline afterwards.

What helps brain fog during perimenopause?

In clinical practice the levers are sleep quality, stress-axis regulation, and consistent support of the systems affected by fluctuating hormones — not stimulants, which tend to borrow clarity from the following day.

Cycle + Thrive was formulated around that reasoning: adaptogenic and botanical ingredients at full clinical doses, chosen for their role in cortisol regulation, sleep architecture and cognitive resilience rather than for label appeal. Read the ingredient-by-ingredient rationale on The Formula, and the reasoning behind the 90-day assessment window on The Science.

This is educational information, not medical advice. Cognitive change has other possible causes — thyroid dysfunction, anemia, sleep apnea, medication effects — and is worth investigating with your clinician.

The holistic practitioner and formulator behind Cycle + Thrive

The Formulator

San Francisco · Nutritionist and applied kinesiologist with almost 40 years of clinical practice, specialising in hormonal health and the perimenopausal transition.

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