What causes night sweats in menopause?

Night sweats are hot flushes that strike while you sleep: sudden heat, drenching sweat, then a chilled, wide-awake 3am. The cause is falling oestrogen scrambling the brain's internal thermostat.

As oestrogen drops through perimenopause, the hypothalamus, your body's thermostat, narrows its comfort zone. Tiny rises in core temperature you would normally never notice now trip the alarm: blood vessels rush heat to the skin, you flush and sweat, then overshoot into a chill. By day that is a hot flush; by night it soaks the sheets and shatters your sleep, which is exactly why the morning after feels so wrecked. The NHS and British Menopause Society group flushes and night sweats together as vasomotor symptoms, the most common menopause symptom, affecting roughly three in four women.

What genuinely helps:

• Cool the room and the bed — a fan, lighter layers, and cotton or bamboo instead of synthetics
• Go easy on evening alcohol and keep caffeine to the morning — both are classic triggers
• Watch spicy food and big hot meals close to bedtime
• Settle the nervous system — paced breathing and a lighter stress load measurably cut how often flushes hit
• Keep cold water and a dry spare top within reach, so a 3am soak does not mean starting the night over
• For disruptive nights, HRT is the single most effective treatment; if it is not right for you, there are non-hormonal prescription options too

Triggers are personal, since the glass of wine that wrecks one woman's night does nothing to another's. That is why tracking beats guessing: a couple of weeks in the daily tracker usually exposes your own pattern. For the daytime version and more fixes, see what helps with hot flushes and why you wake at 3am.

When to push for help: a few damp nights are normal, but you do not have to white-knuckle years of them. If night sweats are stealing your sleep, and with it your energy, mood and focus, that is a GP conversation, not a test of endurance. One flag worth knowing: drenching night sweats alongside unexplained weight loss, fever or a new lump deserve a check to rule out causes that are not menopause.