A 2025 study examined if POI affects a woman’s brain. Researchers looked at if early changes to ovarian hormones might produce differences in brain structure and how it works.
Ovarian hormones have an important influence on the brain. Take oestrogen, for example, some of its protective benefits for the brain include helping brain cells repair themselves and build new connections, whereas progesterone supports the protective insulation of neural fibres that ensures signals move smoothly. These are a few examples of how the ovaries and brain are connected. This means that when changes in ovarian hormones occur, this impacts more than reproductive ability. This impacts the brain.
Oestrogen deficiency has been associated with increased risk of vascular dementia. Dementia is an overarching term for decline in cognitive skills like memory, and Alzheimer’s Disease and vascular dementia are types of dementia. We know the protective benefits of these hormones on the brain so some researchers think that loss of ovarian function, such as in menopause, may be associated with dementia. In fact, research has shown that women are more likely to develop Alzheimer’s Disease than men, and it is not due to life span. This has raised many questions for researchers about the ovarian-brain connection and why we must study this for women’s brain health.
Dr Yuan and colleagues asked, when this hormonal change happens earlier (in POI), what does that mean for the brain? This is a vital question to ask, when research so far is limited in studying risk for brain health in POI.
They looked at 33 women with idiopathic POI who were not yet on HRT and compared them to age-matched women who did not have POI and were not on hormonal contraception. By using magnetic resonance imaging (MRI) scans, they wanted to see if the brain looks or acts differently in POI, compared to women of the same age without POI. The MRI machine contains a very strong magnet which allows us to take images of the brain because the brain is largely comprised of water. From the MRI scans, the researchers were measuring brain structure (the volume of grey matter and white matter, thickness, and more), and how brain regions are connected. They also gave both groups of women a questionnaire about their quality of life and specific menopausal symptoms, and a test to measure different aspects of cognition (like memory, attention, language).
They found:
· Differences in specific brain regions: Looking at the whole brain, researchers did not find any differences between the groups, but when they looked at specific brain regions, such as in areas responsible for memory, they found reduced volume in women with POI, compared to women without POI.
· The age factor: Younger woman who were diagnosed with POI at age 20-35 showed more noticeable structural differences, compared to the women without POI. The older group (diagnosed age 36-40) still showed differences, but at a lesser degree than the younger group. What this means remains a question- are younger women’s brains more vulnerable to the sudden loss of hormones? Does a POI diagnosis earlier in life gives the brain more time to undergo these physical changes?
· Resilience of the brain: The brain is incredibly resilient. The researchers found that in some brain areas, the brain actually boosted its “wiring”, like it was rewiring in response to changes in the hormones. This was especially true for younger women, as a younger age is associated with more brain flexibility.
· Quality of life and mood: Women with POI reported had a negative quality of life because of menopausal symptoms, and higher levels of depression and anxiety, compared to women without POI. The quality-of-life scores correlated with specific brain differences, which might indicate symptoms are associated with how POI affects the brain, but this was not seen for the mood symptoms.
· Cognition: Women with POI performed similarly to women without POI- but this finding might come with a caveat. The way the researchers measured cognitive ability lacked an in-depth measure of cognition, meaning the test may not capture more subtle changes. This is important as the researchers found differences in specific brain regions, such as regions involved in memory.
There are a few key takeaway messages here. Firstly, it is important to remember that these scans are just a “snapshot” in time; not a finished story or a guaranteed outcome for your long-term health. What this means is that we can only draw conclusions about the two groups of women now, not their long-term health. This would require multiple scans over many years. Secondly, new research must further explore women’s brain health in POI as it is an under-researched area. This will ensure that women with POI have the specific tools and treatments they need to keep their brains healthy now and in the future.
Link to Paper: https://doi.org/10.1002/alz.70111
Turning research into self-advocacy:
· Symptoms like “brain fog” can feel scary and overwhelming. It is important to discuss this with your doctor. Asking for a more thorough cognitive review can help ensure your concerns are taken seriously.
· ESHRE guidelines encourage HRT for neurological health.
Want to be involved in my research investigating the brain in POI? Please get in touch and I can keep you up to date with new findings and opportunities (email: pm_cog@kcl.ac.uk).