Vaginitis Vs. Pyometra in Adult Dogs

Older female dogs who have not been spayed have a higher incidence of pyometra.
Janie Airey/Lifesize/Getty Images

Vaginitis and pyometra are medical conditions that only occur in females. Vaginitis is an inflammation of a dog's vagina, the female reproductive passage that leads to the uterus. Pyometra is an infection of a dog's uterus, also known as the womb. Both conditions cause physical discomfort for your dog, but pyometra is much more serious. Vaginitis is more likely to arise in spayed dogs, while pyometra happens more frequently in older intact dogs.

Vaginitis Defined

Vaginitis occurs more often in spayed dogs than in intact dogs. Infectious vaginal bacteria usually occur secondary to a primary cause of inflammation. Anatomical abnormalities, such as vaginal strictures and walls of blocking tissue, contribute to vaginal inflammation. Also, urinary tract infections and foreign objects can instigate vaginitis. After veterinary diagnosis, most cases of vaginitis will resolve, although recurrence is common.

Pyometra Defined

As a female dog progresses through each heat cycle, her uterus opens to become receptive to breeding. During open times, bacteria normally present in the vagina can enter the uterus. If the uterine wall is thickened or diseased and cannot protect itself against invading bacteria, an infection develops. A bacteria called E. coli causes about 90 percent of all pyometras. Older dogs and certain dog breeds, such as collies, rottweilers and golden retrievers, have predispositions for pyometra.

Symptoms and Diagnosis

Symptoms of dogs with vaginitis include vaginal discharge, scooting, licking and frequent urination. Vaginal discharge, licking, increased urination, fever, vomiting, diarrhea and depression are signs of pyometra. Some of these symptoms overlap, although signs of pyometra tend to be more serious. Dogs suffering from pyometra will often refuse to eat or drink, which causes them to become lethargic. Dogs with vaginitis still participate in daily activities. Both conditions need a proper diagnosis by your veterinarian, which can include an exam, health history, X-rays and blood work.


Vaginitis and pyometra treatment protocols often differ dramatically. Vaginitis will typically resolve without treatment unless tissue blockage requires surgery. If vaginal bacterial infection is persistent, antibiotics are in order. Surgical spaying with post-operative antibiotics is the preferred treatment for pyometra. Sometimes, pyometra is treated with hormones that cause uterine contractions to help expel pus. Uterine rupture is a risk for dogs treated with hormones. Pyometra is an emergency; vaginitis is not.


Dogs with recurring vaginitis may have physical characteristics that predispose them to developing the condition. For example, overweight animals may have excessive skin folds surrounding the vaginal opening, promoting uncleanness. Preventing further vaginitis may require surgical removal of skin folds or dietary restrictions to reduce weight. Getting your dog spayed prevents pyometra.