What does your oestrogen level do to your memory and concentration?

Oestrogen has a direct influence on how well brain cells communicate with one another. The hormone plays a role in the growth of nerve projections and the formation of connections between brain cells, and is involved in the production of neurotransmitters. Higher oestrogen levels are associated with better learning and memory performance; lower levels are associated with poorer performance.

During perimenopause, the period before menopause characterised by strongly fluctuating oestrogen levels, many women complain of 'brain fog': forgetfulness, difficulty concentrating and a general sense of mental sluggishness. Longitudinal research confirms small but measurable declines in memory performance that are not fully explained by ageing alone. Reassuringly, the vast majority of women continue to perform within the normal range. Oestrogen also acts as a kind of master switch for the energy metabolism of brain cells. When it falls away, brain cells are less able to produce energy, which may contribute to these neurological complaints.

A striking finding: as menopause progresses, the density of oestrogen receptors in the brain actually increases, probably as compensation for lower levels. However, in an imaging study of healthy middle-aged women, higher receptor density was associated with worse memory performance and more complaints. This appears contradictory and is not yet well understood.

Hormone therapy (HT) with oestrogen does not guarantee better memory or a lower risk of dementia. The effect depends strongly on the timing of initiation (starting early in menopause appears more favourable), the duration, the type of preparation and individual risk factors. Research findings on this point are still contradictory, and no clear-cut advice exists. An exception applies to early or premature menopause (ovaries that stop functioning before the age of forty): for this group, personalised hormone therapy is recommended, at least until the age at which menopause normally occurs, and this is considered probably safe for up to ten years.

Little is still known about the influence of progestogens, which are included alongside oestrogen in many hormone preparations. There are indications that they affect brain function, but the evidence is scarce and their effects are difficult to disentangle from those of oestrogen. If you are considering hormone therapy, or are already using it and are experiencing cognitive complaints, discuss with your doctor which type of preparation and which timing of initiation is most appropriate for you.