You were told it would be a few months of feeling warm. A year, maybe two. Then you would be through it.
For many women, it does not go like that. Around 80% of women have hot flushes or night sweats during the menopause transition, according to the North American Menopause Society (NAMS), and the reality can be far bigger than the warning: longer, harder on sleep, and tied to more of the body than anyone mentioned.
What a hot flush is
A hot flush is a sudden wave of heat, usually through the chest, neck and face. It often comes with sweating, a racing heart and a red face, and sometimes a chill afterwards. It can strike day or night, and last from a few seconds to several minutes.
They can last for years
This is the part that surprises most women. A large study by Avis and colleagues, published in JAMA Internal Medicine in 2015, found that hot flushes and night sweats last about seven years on average, and up to 14 years for some women. They often carry on after the final period. Years of this wears down both body and mind.
Why they happen
Estrogen and progesterone help regulate body temperature. As they fall and swing during perimenopause, the hypothalamus, the brain's temperature control centre, overreacts to small changes, according to the North American Menopause Society. It decides you are too hot when you are not, and throws everything at cooling you down: the heat wave, the sweat, and sometimes the chills that follow. Cold Flushes: The Chill Nobody Mentions covers that other side of the swing.
What they do to sleep
When hot flushes come at night, they are called night sweats, and they can wreck sleep. The US National Institute on Aging says women with frequent hot flushes can wake several times a night, which leads to long-term sleep loss, tiredness, and sometimes mood changes or depression. Poor sleep over months raises stress and can weaken the body's defences, adding to health worries beyond the flushes themselves.
What they may mean for your heart
There is growing evidence that hot flushes are linked with heart and blood vessel health. According to the American Heart Association, women who have frequent, intense hot flushes may have higher blood pressure and stiffer arteries than women who do not. Heart disease is the leading cause of death in women after menopause, so this link matters. It is one more reason to get your blood pressure and cholesterol checked, and to raise your hot flushes with a doctor rather than putting up with them.
What they may mean for your thinking
Brain fog is another hidden side of hot flushes. The hormone changes that cause them can also affect memory and focus. A 2022 study by Weber and colleagues in the Journal of Women's Health found that nearly 60% of women in menopause report trouble concentrating, and that these problems are often worst in women with frequent hot flushes. Most thinking problems improve after menopause, but in the meantime they can affect work, family life and how you feel about yourself.
What the guidelines list
NICE NG23 recommends offering HRT for vasomotor symptoms associated with menopause, which is the medical name for hot flushes and night sweats. The Pakistan Menopause Society's 2026 recommendations name MHT, their word for HRT, as the first-line medicine for hot flushes in women who are eligible and have no reason not to take it. HRT is not right for everyone, so it is a decision to make with your doctor.
For women who cannot or do not want to take HRT, there are other options. NICE NG23 recommends fezolinetant as an option for moderate to severe hot flushes when HRT is unsuitable, and suggests considering menopause-specific CBT, a talking therapy. The National Institute on Aging notes that some medicines first used for depression or blood pressure have been shown to reduce hot flushes. Our page on non-hormonal treatments explains what each one is.
What you can do day to day
The NHS website lists lighter clothing, a cooler bedroom at night, a cool shower, a fan or a cold drink, ways to lower stress, regular exercise and a healthy weight. Among the triggers it suggests cutting down on are spicy food, caffeine, hot drinks and smoking. Cooling Your Nights has more ideas for the nights.
Keep a count. A week or two of noting how many hot flushes you have, and when, shows your doctor how much they are affecting you, and gives you a before picture if you start treatment.
The truth worth knowing
Hot flushes are often brushed off as a short, annoying phase. For many women they are far more than that. Knowing how long they can last, what they touch and what the guidelines offer puts you in a stronger position to ask for help.
If yours are frequent or severe, ask your doctor: "Is HRT an option for me, and if not, what else do the guidelines list?" Our page on hot flushes goes further.