Menopause: a plain guide to what happens

The three stages

Perimenopause is the transition. Hormone levels become erratic, periods change, and most symptoms happen here. It commonly runs four to eight years.

Menopause is the single point twelve months after your final period. In the UK it happens around age 51 on average.

Postmenopause is everything after. Oestrogen settles at a low, steady level. Some symptoms ease. Others, particularly vaginal and urinary ones, tend to continue or arrive later, because they are caused by the ongoing lack of oestrogen rather than by the fluctuation.

Why it happens

You are born with all the eggs you will ever have. Over decades the supply falls, and with it the ovaries' production of oestrogen and progesterone. Eventually ovulation stops, periods stop, and oestrogen settles low.

That is a normal biological process, not a disease. But the consequences of losing oestrogen are real and treatable, which is a different question from whether the process itself is normal.

What changes

Oestrogen does far more than regulate periods. Receptors for it sit throughout the body, which is why its loss shows up in places that seem unrelated:

• Temperature control, run by a region of the brain that is sensitive to oestrogen, which is why hot flushes and night sweats are the classic symptom
• Sleep, both directly and through night sweats
• Mood, memory and concentration
• Bone, which loses density fastest in the first years after menopause
• The vagina, bladder and urethra, where thinning tissue causes dryness, discomfort and repeated infections
• Joints and muscles
• Skin and hair

The NHS notes symptoms usually last seven to nine years, and some persist beyond.

Early and surgical menopause

Menopause before 45 is early. Before 40 it is called premature ovarian insufficiency and needs proper assessment, because the long-term consequences for bone and cardiovascular health are more significant and treatment is usually recommended rather than optional.

Menopause can also be surgical, when the ovaries are removed, or induced by cancer treatment. These arrive suddenly rather than gradually, and symptoms are often more intense for that reason.

How it is diagnosed

Over 45, UK guidance is clear that menopause is diagnosed on symptoms and cycle history, not on a blood test. Hormone levels vary too much day to day for a single reading to mean much.

Under 45 there is more of a role for testing, and under 40 it is important.

What can be done

For most healthy women with symptoms, hormone replacement therapy is the first-line treatment recommended by UK guidance. It replaces the oestrogen that has gone, with progesterone included where you still have a womb to protect the womb lining. It is available through the skin as a patch or gel, or by mouth.

Whether it suits you specifically depends on your history, and that is a question with an actual answer rather than a shrug. Non-hormonal options exist for women who cannot or would rather not take hormones.

Two things worth knowing. Treating symptoms is a legitimate reason to treat: you do not have to be in distress to qualify. And starting treatment is not a permanent commitment.

The bleeding rule

Any vaginal bleeding after twelve months without periods needs a doctor, usually within weeks. It is often nothing serious. It is checked because occasionally it is not, and it is the one symptom on this page that should not wait.