Night sweats are hot flashes that happen while you sleep. In perimenopause they're very common: you wake up hot, damp or soaked, and then struggle to get back to sleep.
In short
- Hot flushes and night sweats affect up to 85% of women around menopause, according to EMAS.
- Lower, uneven estrogen makes the body's thermostat more sensitive.
- Cooling tricks, CBT and hormone therapy can all help, and some night sweats need a check for other causes.
Why do night sweats happen?
Lower estrogen narrows the range of temperatures your brain is comfortable with. A tiny rise in body temperature can trigger a sudden cooling response: blood vessels widen, you feel a wave of heat and you sweat. It can come with a racing heart or anxiety.
Why they hit sleep so hard
Waking up soaked breaks your sleep, and a broken night makes the next day harder: tiredness, low mood, brain fog. More in Why do I wake up at 3am?
What can help?
- Keep the bedroom cool. A fan and layered, breathable bedding.
- Light sleepwear. Cotton or moisture-wicking fabric, with a spare set nearby.
- Cold water by the bed.
- Notice your triggers. Alcohol, spicy food, caffeine and stress are common ones.
- Try CBT. UK guidance recommends it to reduce how much hot flushes and night sweats bother you.
- Ask about treatment. Hormone therapy is the most effective treatment for many women, and non-hormonal medicines are also available.
When to see a doctor
See your doctor if night sweats regularly wake you up or worry you, if you also have a fever or feel shivery, a cough or diarrhoea, or if you're losing weight without trying. Some medicines, anxiety, low blood sugar and infections can also cause night sweats.
Frequently asked questions
Can you have night sweats without hot flashes during the day?
Yes. Some women only notice them at night.
How long do night sweats last in perimenopause?
It varies a lot, from months to several years.
Are night sweats a sign of something serious?
Usually not in perimenopause, but see a doctor if you have weight loss, fever or other new symptoms.
Find your triggers
Log night sweats with one tap in Pausie and see how they line up with your cycle, sleep and triggers. No account, and your diary stays on your phone.
This article is general information, not medical advice. Written by the Pausie team. Published and last reviewed 30 October 2026.
Sources
- EMAS Menopause Essentials: Menopausal symptoms
- NHS: Night sweats
- The Menopause Charity: 2024 NICE menopause guideline
- Sleep Foundation: Menopause and sleep