The Causes and Triggers of Vasomotor Symptoms (VMS)

A look at why hot flashes and night sweats occur during menopausal transition, including triggers to avoid.

Although menopause is a normal part of aging, VMS can be disruptive to a person’s life, and is something that should be discussed with a healthcare provider.

Vasomotor symptoms (VMS) are a collection of symptoms that occur before, during, and after menopause. VMS are commonly known as hot flashes and night sweats (when they occur during sleep). These are sudden episodes of feeling overly warm or hot, flushed skin, sweating, and increased heartrate. After an episode, a person typically experiences chills.

Episodes of VMS can be intense and uncomfortable. Although menopause is a normal part of aging, VMS can be disruptive to a person’s life, and is something that should be discussed with a healthcare provider.

Why do vasomotor symptoms occur?

The exact mechanisms behind vasomotor symptoms are not fully understood, but hormonal changes are thought to play a significant role.

  • When the body begins to approach menopause, levels of estrogen (the female sex hormone) fluctuate and then decline. These changes in hormone levels disrupt the normal functioning of a part of the brain called the hypothalamus.
  • The hypothalamus is sometimes referred to as “the body’s thermostat” because (along with many other functions) it produces the hormones that regulate body temperature.
  • During menopause, the hypothalamus becomes much more sensitive to slight changes in temperature. Hot flashes occur when the hypothalamus senses a slight change in core body temperature and reacts as if it’s a significant change in core temperature.
  • In other words, a hot flash is the body mistakenly sensing that it’s too warm and releasing heat in order to cool down.

What can trigger VMS?

A trigger is something that causes an episode of symptoms. If you are experiencing VMS, it’s helpful to pay attention to potential triggers, keeping a record of where you were and what you were doing when VMS occurred. Avoiding things that can cause VMS can help you avoid episodes in the future.

While VMS triggers can vary from person to person, some common triggers include:

  • Being in a warm or hot environment
  • Stress, anxiety, and intense emotions
  • Consuming hot drinks, spicy foods, and caffeine
  • Consuming alcohol
  • Smoking

Being overweight or obese is also associated with more severe VMS. This is due to the way that higher amounts of body fat affect the body’s ability to regulate heat.

Can hot flashes occur outside of menopause?

VMS is the most common symptom of menopause, but hot flashes can have other causes. Medication side effects, thyroid disorders, certain types of cancer, and cancer treatments are all potential side effects of hot flashes.

It’s also worth mentioning that numerous health conditions and medical procedures can cause premature menopause (menopause before age 40). These include surgery to remove female reproductive organs, chemotherapy, autoimmune diseases, HIV infection, and chromosomal disorders. Premature menopause is also associated with smoking. In other cases, premature menopause occurs for no identifiable reason.

How do you treat vasomotor symptoms?

While VMS typically resolves on its own with time (though it can take years), there are treatments that can help a person manage VMS symptoms during menopause. This includes hormone-based therapies as well as nonhormonal therapies. Avoiding triggers and other lifestyle changes can also be helpful. Your best source of information about managing VMS will be a healthcare provider.

In addition to discussing menopause and VMS, seeing your healthcare provider is essential to taking care of other areas of your health, as the risk of many health conditions increases with age.

Article sources open article sources

Kimberly Peacock and Kari M. Ketvertis. Menopause. StatPearls. August 11, 2022.
Merck Manual Professional Version. Menopause.
Johns Hopkins Medicine. Introduction to Menopause.
The North American Menopause Society. Menopause Glossary.
Tania Lugo and Maggie Tetrokalashvili. Hot Flashes. StatPearls. December 19, 2022.
Mayo Clinic. Hot Flashes. What Causes Hot Flashes?
MedlinePlus. Hypothalamus.
National Institute on Aging. Hot Flashes: What Can I Do?
Cleveland Clinic. Hot Flashes.
Office on Women's Health. Early or premature menopause.

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