Asked which menopause symptom mattered most, 7,285 women said brain fog

Menopause care, its trials, and its treatment guidelines are organised around vasomotor symptoms — hot flushes and night sweats. They are what hormone therapy is licensed to treat, what non-hormonal alternatives are tested against, and what clinical trials use as a primary endpoint.

A UK-wide survey published in BJOG asked 7,285 women a different question: of five symptoms, which matters most to you [s1]. The answer was not a vasomotor symptom.

What was asked

The study was a cross-sectional online survey conducted across the UK from February to March 2023, completed by 7,285 women [s1]. Participants gave anonymised demographic data and rated the importance of five menopause symptoms — low mood, brain fog, aches and pains, feeling tired, and weight gain — on a 10-point Likert scale [s1].

Univariable and multivariable linear regression tested associations between symptom importance scores and age, hormone replacement therapy use, non-HRT treatment, ethnicity, and geographical location [s1].

Note what the design does and does not measure. It measures perceived importance, not prevalence or severity. A woman rating brain fog highly is not necessarily reporting that she has it worse than her hot flushes; she is reporting that it matters more to her.

The findings

Brain fog was the most frequently prioritised symptom overall [s1].

Significant differences in perceived symptom importance were found across age groups, geographic locations, ethnic backgrounds, and treatment status [s1]. Among the moderate-strength associations reported: HRT use was associated with higher importance ratings for brain fog, tiredness, low mood, and aches and pains [s1]. Asian and Black women gave higher importance ratings to brain fog [s1].

The authors' conclusion is that cognitive and psychological symptoms are prominent during menopause, that demographic and treatment variables influence symptom prioritisation, and that the findings support personalised and inclusive menopause care addressing concerns beyond vasomotor symptoms — with implications, they add, for public health policy and financial investment [s1].

The interpretation problem with the HRT association

Women taking hormone therapy rated brain fog, tiredness, low mood, and aches and pains as more important [s1]. There is no way to tell from cross-sectional data which direction this runs.

It could be that hormone therapy relieves vasomotor symptoms effectively, leaving the residual non-vasomotor symptoms as what a woman notices and therefore prioritises. It could be that women with more troubling non-vasomotor symptoms are more likely to seek and obtain hormone therapy in the first place. It could be that women who have engaged with menopause care are more familiar with the vocabulary of brain fog and more willing to name it.

The study reports the association; it cannot adjudicate among these.

What the sample is

An online survey recruits people who see the survey and choose to take it. For a menopause survey distributed in the UK in early 2023 — during a period of unusually high public discussion of menopause — that sample will over-represent women who are engaged with the topic, seeking information, and dissatisfied with their care.

That does not invalidate the ranking. It does mean the 7,285 respondents are not a random sample of UK women at menopause, and the prioritisation of brain fog may be higher in this group than in the population.

The ethnicity finding warrants the same caution and is worth more research either way. Higher importance ratings for brain fog among Asian and Black respondents [s1] could reflect differences in symptom experience, in what is culturally acceptable to report, or in which women in each group chose to respond.

Why symptom priorities are a policy question

If the symptom women most want addressed is not the symptom the treatment pathway is built around, several things follow. Trials that use vasomotor frequency as their primary endpoint will report success on a measure that is not patients' first priority. Guidelines organised by vasomotor indication will underserve the women whose main complaint is cognitive. And services commissioned on vasomotor grounds will be evaluated on the wrong outcome.

The narrower research problem is that "brain fog" is not a validated clinical construct. It is a patient-generated term covering subjective difficulty with concentration, word-finding, and memory, and the evidence that it responds to hormone therapy is much weaker than the evidence for hot flushes. Making it a treatment target requires first making it a measurable one.

Other menopause guidance published the same week illustrates how much of the field still runs on the vasomotor axis: the European Menopause and Andropause Society's clinical guide to endometriosis at menopause frames hormone therapy's indication as managing vasomotor and genitourinary symptoms and maintaining bone health [s2].

What to watch

Whether validated instruments for menopause-related cognitive symptoms are developed and adopted; whether trials add cognitive endpoints; and whether the ethnic differences in symptom prioritisation replicate in samples recruited by probability methods rather than online self-selection.

This article describes a cross-sectional survey and clinical guidance. It is informational only, is not medical advice, and does not recommend any treatment.

Sources

• [s1] Davies R, Goyal A, Nash Z, Hillman S, Davies M, Panay N, Daniels J, Hillard T, Grant B, Briggs P, Robinson L, Hamoda H, Jayasena CN, Factors Associated With Non-Vasomotor Menopause Symptoms Experienced by 7285 Women: A UK-Wide National Survey, BJOG: An International Journal of Obstetrics and Gynaecology, published online 2025-09-01.
• [s2] Erel CT, Nigdelis MP, Ozcivit Erkan IB, et al., Endometriosis and menopausal health: An EMAS clinical guide, Maturitas, 2025;202:108715, published online 2025-09-02.