Fever in the first week after uterine artery embolization is so ordinary that it has a name. Post-embolization syndrome, a constellation of fever, pelvic pain, and an elevated white cell count, occurs in about 21% of patients and resolves on its own. Clinicians are trained not to overreact to it.
The problem is that a far more dangerous complication opens with the same symptoms.
Pyomyoma, also called suppurative leiomyoma, occurs when a fibroid starved of its blood supply becomes infected and turns into an abscess in the wall of the uterus. It is rare. It is also lethal enough that a systematic review in the International Journal of Gynecology & Obstetrics puts the mortality risk at roughly 20% to 30%.
What the New Review Found
That review pooled 52 published reports of pyomyoma occurring outside pregnancy, drawn from a search spanning 1945 to 2024. Fever was the most common presenting symptom, in 72% of patients, followed by abdominal pain in 57%. The most frequently isolated organism was Escherichia coli, in 23% of cases.
Treatment was overwhelmingly surgical. Some 61% of patients had a hysterectomy, and 27% had a myomectomy, the removal of the fibroid alone. Only 12% were managed conservatively, meaning with antibiotics and supportive care rather than an operation. Given the mortality figures, the authors concluded that the benefits of surgery generally outweigh its risks, while noting that myomectomy plus antimicrobials can be an option when future fertility matters.
Two Cases Where the Fever Was Not Routine
A report from a team in Cologne, Germany, describes a 46-year-old woman who developed fever, abdominal pain, and a bloodstream infection on the third day after embolization. Her temperature reached 39.4 degrees Celsius. Blood cultures grew a highly resistant strain of E. coli. Broad-spectrum antibiotics proved inadequate, and the fever and pain persisted.
Imaging was ambiguous because gas inside a treated fibroid is a normal finding after embolization. MRI eventually suggested a superinfected necrotic fibroid, and a vaginal smear grew the same resistant organism found in her blood. She declined a hysterectomy, so surgeons instead performed repeated hysteroscopies to remove the dead tissue and placed an intrauterine gentamicin chain. She recovered with her uterus intact.
An earlier case moved faster and ended differently. A 48-year-old woman arrived 15 days after embolization with fever, chills, and diffuse abdominal pain. Her temperature was 101.5 degrees Fahrenheit, her heart rate was 110, and her white blood cell count was 26,300 with 91% neutrophils. CT showed a distended uterus with intracavitary masses measuring approximately 13 × 13 × 12 cm, containing gas and an air-fluid level. She underwent emergency laparotomy and total hysterectomy.
Antibiotics Alone Are Usually Not Enough
The recurring theme across these reports is that drugs cannot finish the job. An abscess sitting inside dead, devascularized tissue has almost no blood supply, which is precisely what antibiotics rely on to reach an infection.
Definitive treatment therefore pairs intravenous antibiotics with source control: removing the infected fibroid or, more often, the uterus. The German case and a small number of others show that uterus-preserving approaches can succeed in selected patients, but they require repeated procedures and close monitoring.
The Clues That Separate the Two Conditions
Because the opening symptoms overlap, clinicians rely on the course rather than the presentation. Post-embolization syndrome typically appears within days and then improves. Pyomyoma does not, and symptoms persisting beyond a week should raise suspicion.
Reported distinguishing features include foul-smelling vaginal discharge, which is absent in ordinary post-embolization syndrome, high-grade rather than reactive leukocytosis, and failure to improve on appropriate therapy. Imaging alone is a weak tool here. Gas within a treated fibroid is expected after the procedure, so it suggests infection only when accompanied by clinical signs of sepsis.
Risk factors identified across published cases include submucosal fibroids, older age, pre-existing infection, diabetes, intrauterine devices, the postpartum state and immunocompromise. Radiologists have suggested that limiting embolization to fibroids under 8 centimeters may reduce risk, and the German team argued that patients with organisms detected on a pre-procedure vaginal smear should be treated as high risk.
How Worried Should Patients Actually Be
Not very, and the numbers support that. Uterine fibroids affect a large share of women by age 50, and embolization is performed routinely with shorter recovery and lower complication rates than surgery. Pyomyoma after embolization is described consistently as rare, with roughly a dozen cases in the published literature as of the early 2020s.
The practical takeaway is about timing and trajectory, not fear. Fever in the first few days after embolization is common and usually resolves. Fever that persists, worsens, or fails to respond to antibiotics is a different signal. So is foul-smelling discharge or escalating abdominal pain.
Anyone who has had uterine artery embolization and develops those symptoms should contact their care team promptly rather than wait it out, and should make sure the treating clinician knows the date of the embolization. Patients should not adjust or stop prescribed antibiotics on their own. Whether an abscess needs to be drained or removed is a decision that requires imaging and a physician.
Key Questions Answered
What is a pyomyoma?
It is an infected, pus-filled fibroid. After a fibroid loses its blood supply and dies, bacteria can seed the dead tissue and form an abscess inside the wall of the uterus, which can lead to sepsis.
How is it different from post-embolization syndrome?
Post-embolization syndrome is an expected inflammatory reaction with fever, pelvic pain and elevated white cells that improves within days. Pyomyoma presents with the same initial symptoms but does not improve and often worsens.
Why do antibiotics frequently fail on their own?
The infection is in tissue that no longer has a blood supply, so antibiotics cannot reach it at adequate concentrations. Reported cases usually require surgical or hysteroscopic removal of the infected tissue.
Does treatment always mean a hysterectomy?
No. In the pooled review, 61% of patients underwent hysterectomy, and 27% underwent myomectomy. Uterus-preserving management is possible in selected patients.
What warning signs should patients watch for?
Fever that persists beyond the expected window or worsens, foul-smelling vaginal discharge, escalating abdominal pain, and lack of improvement on antibiotics. These warrant prompt medical evaluation.
Is uterine artery embolization safe overall?
It is widely used and generally well tolerated, with faster recovery than surgery. Pyomyoma is a rare complication, reported in a small number of published cases since the procedure was introduced.
