Vasomotor symptoms (VMS) occur due to the constriction or dilation of blood vessels. It commonly affects people during menopause and may cause hot flashes, night sweats, and other symptoms.

Levels of the hormones estrogen and progesterone start to fall in people assigned female at birth when they are around 40 years old. This is when perimenopause — the transition to menopause — begins.

As this transition progresses, people may experience VMS. This occurs due to the constriction (narrowing) or dilation (widening) of blood vessels.

Symptoms include hot flashes, night sweats, heart palpitations, and changes in blood pressure. The most likely reason why these symptoms can occur during menopause is that hormonal shifts affect the body processes that manage blood pressure and temperature.

According to the North American Menopause Society, up to 75% of people assigned female at birth in the United States experience hot flashes around menopause. Hot flashes usually occur over a period lasting from 6 months to 2 years, but you can experience them for up to 10 years.

In the United States, menopause usually begins between the ages of 45–58 years. The average age for menopause is 52 years. Most people enter menopause 12 months after their last period.

Hot flashes and other symptoms can start during perimenopause, while menstruation is still occurring, or they may begin after your periods end. Not everyone has these symptoms, and they can vary in severity among individuals.

You may start menopause earlier in life. In some cases, this may happen naturally. In others, it may be due to surgery, a health condition, or certain types of medical treatment.

Hot flashes are a common VMS during menopause. During a hot flash, you may feel a sudden sensation of heat that affects your chest, neck, and face. The skin in these areas may become red.

Alongside hot flashes, you may experience:

  • sweating, including night sweats
  • sleep disturbances
  • anxiety
  • heart palpitations

Menopause isn’t a health condition. It’s an expected transition that most people assigned female at birth will go through during their life. The hormonal changes that it involves can cause these symptoms.

Hormones play a role in how the cardiovascular system works. As their levels change, they can affect the circulatory system. They can also interfere with how the nervous system manages body temperature.

The symptoms tend to affect people for about a year. However, they can last for as long as a decade in some cases.

If menopause starts as a result of treatment, such as chemotherapy, you may find that once the treatment finishes, the associated symptoms stop and menstruation begins again. Most people tend to regain their periods within 2 years following the end of treatment, but this isn’t true for everyone.

The causes of hot flashes are likely to be neurovascular. This means that they happen when changes occur in the part of the nervous system that affects circulation.

Experts believe that hot flashes result from changes in the part of the brain that regulates body temperature. Sudden drops in estrogen levels may trigger them, but it’s unclear exactly what role this hormone plays.

Some evidence shows that taking supplementary estrogen helps relieve symptoms, but scientists haven’t found a correlation between circulating hormone levels and the severity of symptoms.

Possible triggers for hot flashes include:

  • eating spicy foods
  • drinking coffee or alcohol
  • wearing clothing that’s too warm for the environment
  • having a high temperature
  • smoking
  • experiencing stress
  • undergoing some medical treatments or taking certain drugs
  • having certain health conditions, such as diabetes, tuberculosis, or an overactive thyroid

But they can also occur without any apparent trigger.

Some types of cancer treatment can also lead to hot flashes, regardless of your age or sex.

VMS is common during menopause, but not everyone experiences it. Factors that may increase your risk include smoking and obesity.

Hot flashes may occur over a longer period in Black and Hispanic people assigned female at birth than in white or Asian American people, according to the National Institute on Aging.

Hot flashes and sweating aren’t usually harmful, but they can lead to discomfort, and you may feel embarrassed by the visibility of the symptoms.

In some cases, hot flashes may not relate to menopause but may stem from issues with the nervous or vascular system. These hot flashes may be a sign of changes that could lead to other conditions, such as cardiovascular disease or dementia.

You should see your doctor if:

  • Hot flashes interfere with your daily life.
  • You have other symptoms, such as diarrhea, fatigue, unexplained weight loss, or a general feeling of being unwell.
  • You’re at risk of another health condition, such as diabetes or thyroid problems.

Seeing a doctor can help you get treatment to improve your comfort levels and reduce anxiety. Doctors may also identify other underlying causes of VMS.

Your doctor may recommend medication to help you manage hot flashes.

Hormone therapy

Hormone therapy aims to balance hormone levels in the body. It can help relieve hot flashes and other symptoms, but it’s not suitable for everyone because it can lead to side effects.

Your doctor may not recommend hormone therapy if you have a history or high risk of certain conditions, including cardiovascular disease, stroke, breast cancer, uterine cancer, and liver disease.

Antidepressant drugs

Antidepressants, such as paroxetine (Paxil), may help relieve symptoms. Healthcare professionals will usually prescribe a lower dosage for menopause symptoms than for depression. Possible side effects include headaches, nausea, and drowsiness.

You may have mild symptoms during menopause and don’t need to take medications to manage them. You should discuss with your doctor the benefits and drawbacks of taking medications.

Some lifestyle practices may help you manage hot flashes during menopause.

These include:

  • avoiding known triggers, such as spicy foods, alcohol, and caffeine
  • quitting smoking, if applicable, or avoiding secondhand smoke
  • dressing in layers so that it’s easy to remove a layer if a hot flash occurs
  • carrying a water bottle containing ice water to sip if a hot flash starts
  • keeping a portable fan nearby
  • keeping the bedroom cool at night
  • avoiding exercise immediately before bedtime
  • practicing deep breathing and relaxation exercises
  • following a healthful diet and getting regular exercise
  • reaching or maintaining a moderate weight

Evidence suggests that diet might be able to help reduce menopause symptoms. For example, a 2021 study found that people assigned female at birth who ate a low fat, vegan diet containing whole soybeans reduced their hot flashes by 79%, compared with 49% in the control group.

Some people also use alternative treatments, such as black cohosh, dehydroepiandrosterone (DHEA), or soy isoflavones for hot flashes. But, according to the National Institute on Aging, there isn’t any evidence that these will help, and their long-term effects are unclear.

You should speak with a doctor before using any herbal treatments, supplements, or other types of medication for menopause.

VMS, especially hot flashes, are a common feature of menopause. Not everyone experiences them, and they can affect people differently.

If you find that VMS affects your daily life significantly, you should speak with a doctor, who may recommend treatments or lifestyle changes that can help.