Night sweats are hot flashes that happen while you sleep, and they're a common symptom of the transition into menopause. This guide to night sweats in perimenopause explains why they happen, what can make them worse, how to set up a cooler bedroom and bed, and when to see a doctor about them.
This is general information, not medical advice. Talk to your doctor or pharmacist about your own situation.
The National Institute on Aging (NIA) describes hot flashes as a common symptom of the menopausal transition, and says that when they happen at night, they're called night sweats. The NHS describes a hot flush as your face, neck and chest suddenly feeling very hot or cold, and says episodes can last several minutes.
Mayo Clinic uses a stricter definition: repeated episodes of very heavy sweating during sleep, heavy enough to soak your nightclothes or bedding. Waking up a little sweaty because of too many blankets or a warm room isn't usually counted as night sweats.
During the menopausal transition, the ovaries begin to work less effectively, and production of hormones like estrogen and progesterone declines over time. NIA says these changes are believed to cause hot flashes and other menopausal symptoms.
How long they last varies a lot. The NHS says menopause symptoms usually last 7 to 9 years, sometimes longer, and can change during that time. NIA notes that hot flash patterns differ between women, and that research shows African American and Hispanic women have hot flashes for more years than white and Asian women.
Night sweats can also cost you rest. The NHS says sleep problems may be worse if you also have night sweats. For daytime episodes, see our guide to hot flashes.
NIA says alcohol, spicy foods and caffeine can make menopausal symptoms worse. Things worth watching:
Evening drinks. A glass of wine with dinner or a late coffee.
Spicy food. Especially at dinner, close to bedtime.
Smoking. NIA encourages quitting, for hot flashes and for your overall health.
Weight. NIA says women who are overweight or obese may have more frequent and severe hot flashes.
A warm bedroom. NIA's first tip for hot flashes that keep you up at night is to lower the temperature in your bedroom.
Triggers differ from person to person. NIA suggests noting what triggers your hot flashes and how much they bother you, which can help you make better decisions about managing them.
NIA recommends trying lifestyle changes before medication. For hot flashes that keep you up at night, it suggests you:
Lower the temperature in your bedroom.
Drink small amounts of cold water before bed.
Layer your bedding so you can adjust it during the night.
Turn on a fan.
Dress in layers you can remove at the start of a hot flash.
A few practical extras make a 3 a.m. wake-up easier to handle:
Keep a glass of cold water and a spare set of sleepwear by the bed, so you aren't hunting in the dark.
Lay a towel over your pillow, so you can swap the towel instead of changing the sheets.
Use separate covers if you share a bed with someone who likes it warmer.
Keep the fan within reach, so you can switch it on without getting up.
NIA also says early research suggests hypnotherapy and mindfulness meditation could help with managing hot flashes.
A short log makes patterns easier to spot and makes a doctor's appointment more useful. Each morning, jot down:
The date, and roughly when you woke up
How bad it was: mild, damp or soaked
Any alcohol, caffeine or spicy food the evening before
Bedroom temperature and what bedding you used
How you slept and how you feel today
Your period, if you still have them
Any new medicine or change to a medicine
After two weeks, look for links between the evening before and the night that followed. Our guide to perimenopause symptoms to track before your doctor appointment shows what else is worth noting.
If lifestyle changes aren't enough, NIA describes options to discuss with your doctor:
Hormone therapy. NIA calls it a very effective treatment for hot flashes in women who are able to use it. It also carries risks, including heart attack, stroke, blood clots and breast cancer, and those risks vary with age and other factors.
Nonhormonal medicines. The FDA has approved paroxetine (Brisdelle) to treat hot flashes associated with menopause, and fezolinetant (Veozah) for moderate to severe hot flashes caused by menopause. NIA says nonhormonal options may suit people who can't take hormones or are worried about the risks.
Supplements. NIA says black cohosh, DHEA and soy isoflavones are not proven to work, and some carry risks such as liver damage. Talk with your doctor before taking any herb or supplement.
Night sweats aren't always caused by perimenopause. Mayo Clinic lists other possible causes, including some medicines (such as hormone therapy and drugs used to treat low blood sugar in diabetes), anxiety disorders, alcohol use disorder, sleep disorders such as obstructive sleep apnea, infections such as tuberculosis, and some cancers, such as leukemia and non-Hodgkin lymphoma. That doesn't mean something serious is going on, but it's why new or unusual night sweats deserve a check.
Mayo Clinic suggests making an appointment if night sweats:
happen on a regular basis
interrupt your sleep
come with a fever, weight loss, pain in a specific area, cough, diarrhea or other symptoms that concern you
start months or years after your menopause symptoms ended
The NHS also suggests seeing a GP if you think you have symptoms of perimenopause and want to know your options, if you have a fast heartbeat (palpitations), or if you have any vaginal bleeding after 12 months or more without a period. It notes that early advice can help reduce the effects of menopause and perimenopause on your health, relationships and work.
They can be. The NHS lists night sweats among the symptoms of menopause and perimenopause, and early signs often include changes to your periods. Other conditions can cause night sweats too, so mention them to your doctor.
It varies. NIA says hot flashes can last for many years, and the NHS says menopause symptoms usually last 7 to 9 years, sometimes longer.
You may not be able to stop one once it starts, but NIA's tips can help: a cooler bedroom, a fan, layered bedding and small sips of cold water before bed.
See a doctor if they happen regularly, disrupt your sleep, come with fever, weight loss or other worrying symptoms, or start after your menopause symptoms had ended.
My Midlife Story: Menopause is an iPhone journal for anyone going through perimenopause or menopause who wants to track changes and prepare for doctor visits. You can log symptoms such as hot flashes, night sweats and sleep with one tap, saved with the date and time, then build a one-page visit brief to preview, edit, save as a PDF or print. It doesn't diagnose or recommend treatment, needs no account, has no ads and is free with an optional Premium subscription.
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