Why Am I Feeling Like This?
Understanding the Symptoms of Perimenopause and Menopause
One of the hardest parts of perimenopause is not always the symptom itself.
It is not knowing whether the symptom belongs to perimenopause at all.
A disrupted menstrual cycle may seem understandable. But waking repeatedly during the night, forgetting familiar words, feeling unusually anxious or noticing that your heart suddenly races can appear entirely unrelated.
Perimenopause begins with changing ovarian function, but ovarian hormones carry information to tissues throughout the body. As the pattern of those signals changes, the effects can appear in places that seem to have nothing to do with reproduction.
This does not mean every symptom is hormonal. Understanding the biology gives us a better starting point for working out what may be connected, and what needs investigating separately.
Hormones are messages
Hormones are chemical messengers. They travel through the bloodstream, but they do not give the same instruction to every cell they pass.
A hormone can influence a cell only if that cell has the appropriate receptor: a protein able to recognise it and respond. Oestrogen receptors are found in reproductive tissues, but also in the brain, bone, blood vessels, skin, muscle, bladder, urethra, vagina and vulva.
Oestradiol—the main form of oestrogen during the reproductive years—therefore participates in far more than the menstrual cycle. It influences bone remodelling, blood-vessel function and signalling within particular brain networks.
Progesterone also has wider effects. It is produced in substantial amounts after ovulation, and one of its metabolites interacts with the brain’s GABA system, which is involved in sleep, calm and the response to stress.
Their effects depend on the tissue, other biological signals and the sensitivity of the individual woman. That is why “low oestrogen causes symptoms” is not a sufficient explanation.
Fluctuation and decline are not the same.
During perimenopause, ovarian hormone production does not usually fall in a smooth line. Ovulation becomes less consistent, progesterone exposure changes and oestradiol may rise sharply as well as fall.
The body is responding not simply to fewer hormones, but to the changing patterns of exposure.
After menopause, that variability usually reduces. Oestradiol remains much lower and progesterone no longer rises in a monthly cycle. Some symptoms lessen, while others may continue or emerge in response to sustained lower oestrogen.
Our articles What is Perimenopause?, What is Menopause? and What is Postmenopause? explain these stages in more detail.
Why the brain notices
The brain is not watching the hormonal transition from a distance. It is part of it.
Oestrogen receptors are present in regions involved in temperature regulation, sleep, memory, attention and mood. Changing oestradiol does not produce one predictable brain symptom, but it can alter the conditions within which these systems operate.
Hot flushes provide one of the clearest examples. The hypothalamus , in the brain, helps keep core body temperature within a narrow range. Falling oestrogen alters signalling in a group of hypothalamic cells known as KNDy neurons. This can make the temperature-control system trigger heat-loss responses—skin blood vessels widening and sweating—in response to a very small temperature change.
A hot flush is therefore not imagined heat. It is a measurable thermoregulatory event generated by the brain’s attempt to cool the body.
Sleep, mood and cognitive symptoms are more complex. Hormonal signalling may contribute directly, but night sweats, stress, low mood and repeated sleep disruption also affect one another. Repeated waking can lead to poorer concentration, greater emotional reactivity, fatigue and increased sensitivity to pain.
What feels like five separate symptoms may sometimes be one biological change creating a chain of consequences.
Not every symptom has one explanation
The phrase “menopause symptoms” can suggest that every symptom shares a single cause. It does not.
Vaginal dryness and urinary discomfort are closely associated with lower oestrogen acting on local tissues. Hot flushes involve specific signalling within the brain’s temperature-regulation system. Joint pain is commonly reported, but its mechanisms are less clearly defined and may be hormonal, inflammatory, musculoskeletal or age-related.
Even within one symptom, several influences may be present. Poor sleep may result from night sweats, but it can also be affected by anxiety, pain, restless legs, sleep apnoea, alcohol, medication or changing daily routines.
The purpose of understanding the biology is not to force every experience into a hormonal box. It is to ask better questions.
Why experiences differ
Some women experience few symptoms; others find their daily lives profoundly affected. The difference is not a measure of strength, attitude or ability to cope.
Genes, previous sensitivity to hormonal changes, health, medication, sleep, stress and social circumstances can all influence symptom severity. Research shows that symptoms often occur in clusters, although the pattern differs between women.
Two women can be at the same reproductive stage and experience it very differently.
When “it’s menopause” is not enough
Recognising a possible hormonal connection is useful. Assuming that every new symptom must be menopause can be unsafe.
Thyroid disease, iron deficiency, depression, heart-rhythm disturbances, diabetes, medication effects and sleep disorders can overlap with common menopause complaints. New, severe, persistent or unusual symptoms should be assessed properly.
Menopause may be part of the explanation without being the whole explanation.
Begin with the pattern
Symptoms are information. Recording what happens, when it occurs, its relationship to the menstrual cycle and its effect on daily life can make an unclear experience easier to discuss.
Our Perimenopause Symptom Checklist can help you identify and record changes before speaking to a healthcare professional or considering what support you may need.
[Access the Menopause Symptom Checklist]
The individual articles in this section explore symptoms such as sleep disruption, anxiety, brain fog, hot flushes and joint pain in greater depth. Each asks what is known, what remains uncertain and what else should be considered.
You are not expected to diagnose the biology yourself.
But you are entitled to understand why one hormonal transition can be felt in so many different parts of your life.
The symptoms are not random.
Neither should the questions we ask about them be.
Further reading and evidence
NICE: Menopause—identification and management
https://www.nice.org.uk/guidance/ng23
The menopause transition and women’s health at midlife: findings from the Study of Women’s Health Across the Nation
https://pmc.ncbi.nlm.nih.gov/articles/PMC6784846/
Estrogen hormone biology
https://pmc.ncbi.nlm.nih.gov/articles/PMC6206851/
Vasomotor symptoms during menopause: a practical guide on current treatments and future perspectives
https://pmc.ncbi.nlm.nih.gov/articles/PMC9938702/
A review of cognitive, sleep and mood changes in the menopausal transition