Uterine fibroids, also known as leiomyomas, are common, non-cancerous growths that develop within or on the muscular walls of the uterus. They affect a significant portion of the population with a uterus, yet many individuals remain unaware they have them because they cause no symptoms. When symptoms do occur, they typically involve localized discomfort, heavy bleeding, or pressure on nearby organs. Fibroids are localized tumors that do not trigger a systemic reaction like a fever. A fever is a sign of a secondary complication or an entirely unrelated illness, and its presence should always be taken seriously.
Why Typical Fibroids Do Not Cause Fever
Fibroids are benign masses composed of muscle and fibrous tissue, with growth primarily regulated by hormones like estrogen. Because they are localized growths, they do not incite the body’s generalized immune response that results in a fever. Common symptoms, such as heavy menstrual bleeding and pelvic pressure, are mechanical and regional. These effects stem from the mass occupying space or interfering with the normal function of the uterus, not from a widespread infection or inflammatory process. A baseline fibroid condition is not linked to an elevated core body temperature.
Degeneration and Infection: When Fibroids Cause Fever
The presence of fever in a patient with fibroids almost always signals a complication, most frequently involving tissue death or bacterial invasion. The most common mechanism is fibroid degeneration, which occurs when a fibroid outgrows the capacity of its blood vessels to supply adequate oxygen and nutrients. This lack of blood flow, known as ischemia, causes the fibroid tissue to die, releasing inflammatory mediators into the body. This inflammatory response can lead to localized acute pain and often results in a low-grade fever, typically between 100.4 and 102.2 degrees Fahrenheit (38.0 and 39.0 degrees Celsius).
Red degeneration, or hemorrhagic infarction, is particularly common during pregnancy when the rapidly enlarging uterus compromises the fibroid’s blood supply. Internal bleeding cause sharp, localized abdominal pain and the accompanying low-grade temperature elevation. While degeneration involves sterile inflammation, a more severe complication is pyomyoma, where a necrotic fibroid becomes infected by bacteria. Pyomyoma is a life-threatening condition that occurs when the dead tissue provides a breeding ground for microorganisms, resulting in a higher fever and systemic signs of infection. This process requires urgent medical intervention and is often associated with severe pain that lasts longer than the typical self-limiting pain of simple degeneration.
Other Causes of Fever in Patients with Fibroids
It is statistically more likely that a fever in a patient with fibroids is caused by an entirely separate condition, rather than the fibroids themselves. Since fibroids can mechanically press on the bladder, patients may have an increased risk of developing a Urinary Tract Infection (UTI). A UTI causes fever, burning with urination, and lower abdominal pain, symptoms that may be incorrectly attributed to the fibroids.
Another gynecological cause of fever and pelvic pain is Pelvic Inflammatory Disease (PID), an infection of the upper reproductive organs, including the uterus and fallopian tubes. PID can present with a fever of 100.4°F or higher, severe lower abdominal pain, and abnormal vaginal discharge.
Furthermore, any common viral or bacterial illness, such as the flu or a cold, can cause a fever, and these are often mistaken as being connected to the known fibroid diagnosis. A medical professional must consider all potential sources to accurately diagnose the cause of the elevated temperature.
Warning Signs and Seeking Care
Any fever, defined as a body temperature above 100.4°F (38.0°C), in a patient with known fibroids warrants a medical evaluation to rule out a serious complication. Immediate medical attention is necessary if the fever is high, particularly above 102°F (38.9°C), or is accompanied by severe, unrelenting pelvic or abdominal pain. Severe pain that is sudden in onset and localized to one area of the abdomen suggests a potential complication like acute degeneration or a twisted pedunculated fibroid stalk.
Other concerning signs include a foul-smelling or discolored vaginal discharge, which may indicate an infection, or signs of shock such as dizziness, rapid heart rate, or fainting. These symptoms suggest the possibility of a serious infection like pyomyoma or internal bleeding, which can become life-threatening without prompt treatment. Consulting a physician allows for a proper differential diagnosis, including blood tests and imaging, to determine the exact cause of the fever and ensure appropriate and timely care.