Pyometra (Uterine Infection) in Dogs

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Pyometra (Uterine Infection) in Dogs

Female dogs that have not been spayed are at risk of developing a life-threatening infection in their uterus (womb), called a pyometra. This infection requires urgent veterinary attention. Continue reading to learn more about symptoms, prevention, and treatment of pyometra in dogs.

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Symptoms of Pyometra in Dogs

Please keep in mind that early signs of pyometra are not always obvious. If your female dog seems ill or has vaginal discharge, she should be examined by a vet right away. This is especially important if your dog isn’t spayed.

  • Mucous or bloody vaginal discharge (may or may not be present)
  • Lethargy or low energy
  • Drinking more and urinating more
  • Vomiting
  • Anorexia (decreased or absent appetite)
  • Heat cycle may seem to last longer
  • Licking the vulva more than normal
  • Swollen or painful abdomen
  • Weakness or collapse

Causes of Pyometra in Dogs

Pyometra is caused by a bacterial infection within the uterus. The most common culprit is Escherichia coli (E.coli), which is typically found in feces. The uterine infection usually occurs a few weeks after a female dog has had her heat cycle. Pus fills the uterus and a malodorous vaginal discharge may be present. However, in many cases of pyometra, the pus remains trapped inside the uterus. If left untreated, this type of infection can lead to dehydration, sepsis, kidney failure, and even death.

Every time a female dog goes into heat (typically twice a year) they experience the hormonal changes associated with pregnancy, even if they don’t actually become pregnant. These hormones cause changes to the uterus that make infection more likely as the dog ages. As a result, pyometra is most commonly seen in older, female dogs that haven’t been spayed. However, this type of uterine infection can happen in an unspayed female dog of any age. Hormone fluctuations that occur with each heat cycle also place stress on the dog’s immune system, increasing her risk of infection.

Progesterone-based hormone injections that are used to prevent a dog from going into heat, or for treatment of other conditions, can also increase the risk of pyometra developing. These hormone treatments cause similar changes to the uterus that would be experienced during a normal heat cycle.

What can you do to help your dog?

Any unspayed female dog is at risk of developing pyometra. If you don’t intend to breed your dog, speak with your vet for recommendations about the best time to have her spayed.

If your dog isn’t spayed, be aware of the common symptoms of pyometra, and have her examined immediately if you have any concerns. Once a dog has developed pyometra, she will typically need emergency surgery to remove the uterus. The sooner the surgery can be performed, the better her chances of survival.

Treatment of Pyometra

If your dog is showing signs of pyometra, she must be examined by a vet right away. Your vet will take a thorough history of your dog’s health and behaviors, including her appetite, water intake, and date and duration of her last heat cycle.

The vet will likely recommend some diagnostics for a better evaluation of your dog’s condition. These include an ultrasound to assess her uterus and blood tests to check her liver and kidney function, levels of red and white blood cells, and hydration status.

Your dog may need to be hospitalized so she can receive intravenous fluids and medications. This will help ensure that she is stabilized before surgery. Emergency surgery is performed as soon as the patient can safely be put under general anesthesia.

When should you visit the vet?

  • If you suspect that your dog has a pyometra, please contact your vet immediately.
  • Alternatively, you can book the next available appointment with FirstVet. One of our experienced vets will provide emergency advice and guide you to your nearest vet clinic if pyometra is suspected.

Read more:

Mammary Tumors in Dogs

Does My Dog Have Mastitis? How to identify, treat, and prevent mastitis in nursing mothers

Gastric Dilatation and Volvulus

Need to speak with a veterinarian regarding your dog’s pyometra or another condition?

Click here to schedule a video consult to speak to one of our vets. You can also download the FirstVet app from the Apple App Store and Google Play Stores.

Published: 9/18/2020
Last updated: 10/28/2021

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