A tubo-ovarian abscess (TOA) can form in the organs of the female reproductive system. The condition requires urgent medical care, including antibiotics and possibly surgery.

This article outlines the symptoms, causes, diagnosis, and treatment options for a TOA. It also explores risk factors, at-home care, and when to seek medical attention.

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

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A TOA is an inflammatory mass in the adnexa, which comprises the uterus, bilateral ovaries, fallopian tubes, and ligaments. This constitutes the female reproductive system.

A TOA usually develops as a complication of pelvic inflammatory disease (PID). Without treatment, pus from a vaginal or cervical infection can travel upward to the uterus lining or endometrium, through a fallopian tube, and into the peritoneal cavity, where it forms a mass or TOA.

Depending on its composition, doctors categorize a mass as solid, cystic, or complex.

People with this condition require early diagnosis and urgent medical care to prevent further complications. This is because a TOA can rupture and lead to sepsis, which can be life threatening.

According to 2022 research, the majority of people with a TOA are sexually active females of reproductive age. Nearly 60% of people with the condition have never given birth.

Research from 2018 indicates that when severe sepsis occurs, people with a TOA have a mortality rate of 5–10%. Sepsis happens when the immune system has an exaggerated immune response to an infection.

Learn more about sepsis here.

A person with a TOA may feel a mass in their lower abdomen or pelvis. They may also have symptoms of an infection, which include:

After examining and testing a person, a doctor may find the following symptoms of a TOA:

  • pus-filled ovaries
  • cervical excitation, or tenderness when a doctor moves the cervix with their gloved hand
  • elevated levels of white blood cells

A person may develop a TOA due to the following:

PID

PID-causing pathogens present in the cervix or vagina can travel up to the endometrium and ascend through the fallopian tubes into the peritoneal cavity, where they form a mass.

Most cases of a TOA are associated with peritonitis — inflammation of the peritoneal cavity lining.

According to a 2018 study published in the International Journal of Obstetrics and Gynecology, a TOA is usually polymicrobial in 30–40% of cases. This means multiple pathogens such as bacteria or fungi may be present.

Researchers have identified some microorganisms in TOA cases. They include:

It is important to note that sexually transmitted and nonsexually transmitted infections can cause a TOA.

Infected adjacent organ

Infections from adjacent organs, such as the appendix, may spread and cause a TOA. The blood can also carry infections from elsewhere in the body.

A TOA may also arise when cancer invades healthy cells of the female reproductive system and spreads to surrounding tissues.

Xanthogranulomatous inflammation

This rare chronic inflammation destroys healthy kidney and gall bladder tissues, replacing them with lipid-containing macrophages.

Researchers do not fully understand how xanthogranulomatous inflammation causes a TOA. However, they assume it may be due to inflammatory responses from infections, failed antibiotic therapy, or endometriosis.

Additionally, if xanthogranulomatous inflammation occurs in the female genital tract, it may make mass-like lesions to form that can invade healthy surrounding tissues.

Apart from infections, some risk factors can increase a person’s chances of developing a TOA. They include:

  • Age: While females aged 15–25 are more susceptible, older females may have larger abscesses with higher inflammatory markers.
  • Multiple sex partners: Having multiple sexual partners can increase a person’s chances of contracting sexually transmitted infections that cause a TOA.
  • Intrauterine device (IUD): According to 2017 research, long-term IUD use can increase a person’s chances of a TOA if they are immunocompromised.
  • Endometriosis: Those with coexisting endometriosis are 2.3% more likely to develop a TOA. This may be due to a bacterial invasion. In addition, fluids in the endometrium may be a good breeding ground for pathogens to thrive.
  • PID: People with untreated PID are more likely to develop a TOA as a complication of the disease. Currently, about 20% of those with PID have a TOA.

Diagnosing a TOA can be challenging for doctors. This is because it shares common signs and symptoms with other health conditions, such as:

To diagnose a TOA, the doctor will take a person’s medical history and perform a pelvic exam to assess the size, consistency, and mobility of the uterus or adnexa.

In addition, the doctor may order the following tests:

  • Blood test: A blood test may reveal elevated levels of some clinical biomarkers of a TOA, such as white blood cell count, erythrocyte sedimentation rate, and C-reactive protein. It can also help healthcare professionals detect the presence of pathogens in the body.
  • Urine test: A urine test may help a doctor rule out any underlying urinary tract infection responsible for the condition.
  • Transvaginal ultrasound: This test produces clear images of the female pelvic organs. It can help doctors detect an anomaly in the anatomical architecture of the uterus, ovaries, tubes, cervix, and pelvis.
  • Laparoscopy: This is a minimally invasive procedure that helps a surgeon access the internal structures of the pelvis.
  • Endometrial biopsy: Following a laparoscopy, the doctor may take a small piece of tissue from the uterus and examine it under the microscope.

Learn more about a pelvic exam here.

Treatment for a TOA usually requires hospitalization and may include the following:

Antibiotic medication

This is usually the first-line treatment for people with a TOA. A doctor may prescribe the following dosages of broad-spectrum antibiotics:

  • 1 milligram (mg) of intramuscular ceftriaxone plus 100 mg of oral doxycycline administered twice daily
  • 900 mg intravenous (IV) clindamycin administered every 8 hours with 5 mg per kilogram of body weight IV gentamicin
  • Alternative: 3 grams of ampicillin/sulbactam administered every 6 hours with 100 mg oral dosages of doxycycline administered twice daily

Healthcare professionals will administer fluids and medications in the first 24 hours following the diagnosis of a TOA. They will observe a person’s vital signs until symptoms improve significantly.

If antibiotic therapy is effective, a patient may spend 3–4 days in the hospital.

Research from 2020 suggests that antibiotic therapy is effective in 70% of cases.

Learn about the side effects of antibiotics here.

Doctors may recommend surgery for a TOA in the following circumstances:

  • an abscess that is too large
  • ineffective antibiotic therapy
  • rupture of the TOA

Surgery aims to drain the abscess, remove the affected parts, and prevent further damage. This includes:

  • Laparoscopy: This minimally invasive surgery allows doctors to drain any abscess and remove damaged tissues in the female reproductive system.
  • Salpingectomy: If there is damage to the fallopian tube, the doctor will perform a salpingectomy to remove it and prevent further infection.
  • Oophorectomy: Following a TOA rupture, a doctor will remove a damaged ovary by performing an oophorectomy.

A person may spend 7–10 days in the hospital after TOA surgery.

A person can practice the following self-care tips at home after their hospital discharge:

  • get plenty of rest
  • avoid lifting heavy weights
  • eat a balanced diet
  • drink enough water
  • avoid sexual intercourse for at least 6 weeks
  • wear loose clothing
  • clean the incision site following the doctor’s instructions
  • take medications according to the prescription

A person should contact a doctor immediately if they have any symptoms of a TOA. Usually, a doctor will recommend starting treatment right away if they suspect a TOA.

If a person experiences any unpleasant side effects after treatment, they should discuss them with a doctor.

Early diagnosis and treatment for a TOA, which includes drug therapy and surgery, can help preserve fertility and prevent life threatening complications such as septic shock, ectopic pregnancy, abscess rupture, and death.

Recovery from a TOA is often slow. People may develop chronic pelvic pain and have an increased risk of ectopic pregnancies in the future.

A 2020 study suggests that a minimally invasive approach and conservative therapy can improve outcomes.

Generally, the outlook depends on the severity of the condition, but a person’s age and overall health can also influence recovery.

A TOA is a pus-filled, inflammatory mass in the fallopian tubes or ovaries. It is usually a complication of PID.

A TOA requires immediate treatment to avoid complications that can be life threatening, such as sepsis.

Doctors can diagnose a TOA using a physical exam and various tests.

The first-line treatment for a TOA is antibiotics. Sometimes, a person may require surgery to drain the abscess or remove damaged structures.