The cause of fibromyalgia is still a bit of a mystery. But there’s research that points to several possible factors, including risk factors that may raise a person’s chance of developing the condition.

Fibromyalgia is a condition that causes pain throughout your body. It also leads to fatigue, sleep issues, and other symptoms. People with this condition may be more sensitive to pain than those without the condition.

Fibromyalgia is one of the most common long-term (chronic) pain conditions in the world. It affects about 10 million people in the United States, according to the National Fibromyalgia Association (NFA).

There are several symptoms of fibromyalgia. These include:

Experts don’t know exactly what causes fibromyalgia, but there are a few factors:

Unusual pain signaling

In people with fibromyalgia, the nervous system may not process pain signals in the usual way. Abnormal levels of chemicals in the brain, spinal cord, and nerves that carry these signals may make people more sensitive to the feeling of pain.

Hormone imbalances

Hormones such as serotonin, norepinephrine (noradrenaline), and dopamine help your body to process pain. Lower-than-normal levels of these hormones in the brain and nervous system may interrupt pain signals and increase your sensitivity to them.

Cytokines

IL-6 and IL-8 are cytokines, which are substances secreted by cells in the immune system. These particular molecules play a role in inflammation and are associated with fibromyalgia.

Genetics

Fibromyalgia can run in families. It’s likely that there’s an unidentified genetic irregularity that increases certain people’s risk of the condition. Certain genes may control the way the body regulates pain responses.

Scientists speculate that people with fibromyalgia carry one or more genes that cause them to react strongly to triggers that others might not find as painful.

Triggers

For many people, symptoms begin after emotional or physical trauma, or a bout with an infectious disease. These factors do not likely cause fibromyalgia by themselves. However, they may trigger the onset in people who are already at risk by changing the nervous system’s response to pain.

Fibromyalgia triggers may also include:

  • infections such as the flu
  • repeated injuries
  • surgery
  • a traumatic life event like a breakup, divorce, or the death of a loved one
  • childbirth

Sleep disturbances

Problems getting enough sleep or spending enough time in the deepest stages of sleep are common in this condition. But doctors aren’t sure whether this is a symptom or a cause of fibromyalgia. Irregular sleep patterns can affect the levels of some brain chemicals.

Several factors increase the risk of fibromyalgia. But having one of these following risk factors does not mean you’ll have a diagnosis of this condition.

Sex

Fibromyalgia is more common in females than in males, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Scientists believe females experience pain differently than males.

This is partly because reproductive hormones, such as estrogen, make females more sensitive to pain. It’s why pain levels fluctuate during a menstrual cycle when estrogen levels rise and fall.

Menopause, which also results in lowered levels of estrogen, is another potential risk factor for fibromyalgia.

Age

According to the NFA, most people with fibromyalgia receive a diagnosis in early to middle adulthood, between the ages of 20 and 50.

Family history

If you have a close family member with fibromyalgia, you’re more likely to receive a diagnosis of the condition.

Sleep disorders

It’s not known whether sleep problems are a symptom or a cause of fibromyalgia. Some people who have disorders affecting sleep, such as sleep apnea and restless leg syndrome, are more likely to have the condition.

Other rheumatic diseases

Rheumatic diseases affect the joints, muscles, and bones. People who have another rheumatic disease are more likely to have fibromyalgia. These diseases include:

Depression

The strain of living with chronic pain can also cause depression. Also, depression can make your pain worse.

Other possible risk factors for fibromyalgia include not exercising, exercising too much, or undergoing surgery.

Your outlook depends on the severity of your fibromyalgia. The condition usually continues long term, but it’s milder in some people than in others.

Fibromyalgia is not life threatening, but it can be life changing. Learning how to manage your condition may give you an outcome that best suits you. Talk with your doctor about finding the best treatment and support options.