Women's health and longevity. Why menopause is a turning point, not the end of prevention

1. Menopause as a biological turning point, not a single event

Menopause is formally defined as the day falling 12 months after the last menstrual period — but what happens around that date stretches over years. The preceding phase (perimenopause) and the one that follows (early postmenopause) bring the greatest hormonal variability of a woman''s adult life: estradiol falls non-linearly, cycles become irregular, and some women experience vasomotor symptoms. The average age of menopause in European populations is around 51, but individual variation is wide — and as the next section shows, that variation matters for health in the decades ahead.

2. Why the age of menopause matters for longevity

Estrogens protect blood vessels — they support endothelial elasticity and a favourable lipid profile. Their sharp decline at menopause removes that protection, and the timing of this shift carries statistical weight. A systematic meta-analysis published in JAMA Cardiology (Muka et al., 2016), pooling data from many cohort studies, found that women with premature menopause (before age 40) had a higher risk of coronary heart disease and stroke than women whose menopause occurred after 45. This does not mean every woman with earlier menopause will fall ill — it is a population-level association, not an individual prognosis — but it justifies earlier, more attentive cardiovascular prevention in this group. We describe what such prevention looks like in Heart health and longevity.

3. Bone: rapid density loss in the menopausal window

Bone is continuously remodelled tissue, and estrogens restrain the excessive activity of the cells that break it down (osteoclasts). The SWAN cohort (Study of Women''s Health Across the Nation), reported by Finkelstein and colleagues (Journal of Clinical Endocrinology & Metabolism, 2008), showed that the rate of bone mineral density loss accelerates sharply within a narrow window: the year before the final menstrual period and roughly two years after it. It is this short span, rather than postmenopause spread evenly over decades, that accounts for much of the cumulative bone loss leading toward osteoporosis. The practical consequence: a conversation about bone density and possible DEXA scanning makes sense already around perimenopause, not only after osteoporosis has been diagnosed.

4. Menopausal hormone therapy — what the large trials show, and what they do not

The debate about menopausal hormone therapy (MHT) tends to be polarised. The longest follow-up to date — an 18-year analysis of two randomised Women''s Health Initiative trials including more than 27,000 women (Manson et al., JAMA, 2017) — found that MHT used for a median of 5.6–7.2 years was associated with neither increased nor decreased risk of all-cause, cardiovascular or cancer mortality compared with placebo across the whole study population. That is an important, reassuring long-term result — but it does not mean MHT is appropriate or necessary for every woman. The effect depends on the age at which therapy starts, the preparation used and the individual risk profile; we discuss the so-called timing hypothesis in Hormones and longevity. The decision is always made individually with a gynaecologist.

5. Biomarkers worth watching: AMH and estradiol in planning prevention

Anti-Müllerian hormone (AMH) reflects ovarian reserve and, alongside age, improves the accuracy of estimating the approximate time to menopause — a long-term cohort study (Broer et al., Journal of Clinical Endocrinology & Metabolism, 2011) showed high accuracy for such a predictive model. This is useful information when planning perimenopausal prevention (when to start the conversation about bone and heart health), but it is neither a diagnostic test for disease nor a precise clock counting down to menopause for an individual. Estradiol, the main estrogen, is sometimes measured in the work-up of cycle disturbances and perimenopausal symptoms — like AMH, its interpretation always requires clinical context and belongs with a gynaecologist or endocrinologist.

6. Does women''s healthspan end with hormones?

No — and that is one of the more important things to take from this article. Hormones are one element of the picture, not the whole picture. Regular physical activity, including bone-loading resistance training, sleep, cardiovascular prevention and screening matched to age and family history all have documented value regardless of any decision about MHT. A woman who does not use hormone therapy still has many other well-supported tools for healthy ageing.

Study limitations

The Muka meta-analysis rests largely on observational studies — it shows an association between age at menopause and cardiovascular risk, but does not prove direct causation; confounders common to both earlier menopause and cardiovascular disease are possible (for example smoking, which accelerates both). SWAN studied a multi-ethnic cohort in the United States — the rate of bone loss may differ in other populations and depends on factors such as diet and physical activity that are not fully captured here. Women''s Health Initiative participants were on average 63 years old at enrolment — older than the typical age of menopause onset — so findings about mortality do not translate directly to women starting MHT soon after perimenopausal symptoms appear (this is the essence of the timing hypothesis). The AMH predictive model from Broer and colleagues applies to healthy, normally ovulating women; its accuracy in women with cycle disorders or other gynaecological conditions has not been confirmed in the same way.

One small step

If you notice the first signs of perimenopause (irregular cycles, hot flushes, changes in sleep), book a visit with a gynaecologist — not to "do something about it" pharmacologically, but to agree on an individual prevention plan, including when to discuss bone density and assess cardiovascular risk.