08/17/2025
Pyometra in Pets
Pyometra is a serious bacterial infection of the uterus that occurs most often in older, intact (unspayed) female dogs and cats. The infection tends to occur about a month after the dog or cat has been in heat. If unrecognized and untreated, pyometra can lead to a systemic infection or blood poisoning.
Pyometra is often described as being “open” or “closed.” With “open” pyometra, the cervix (the part of the uterus that connects with the va**na) is open, allowing the fluid that forms in the uterus due to the infection to drain out of the body.
With “closed” pyometra, where the cervix is closed, the fluid in the uterus cannot drain. Instead, it builds up, stretching the uterine walls and potentially causing the uterus to rupture. If this occurs, the infection may spread throughout the abdomen leading to shock and, potentially, death.
About 25% of unspayed dogs will develop pyometra before the age of 10.
Cats develop pyometra much less commonly than dogs. But some breeds are at higher risk.
Early in the course of pyometra, there may be no clinical signs. As the infection worsens, signs may include:
Lethargy
Lack of appetite
Vomiting
Diarrhea
Excessive thirst
Frequent urination
White or bloody va**nal discharge
Cats may show very minimal clinical signs
In most cases, emergency surgery to remove the pet’s uterus is necessary. Pets with pyometra are often dehydrated, feverish, and may have low blood sugar that must be corrected prior to surgery.
The best way to prevent pyometra is to have your pet spayed. Spaying removes the hormonal stimulation that causes heat cycles, and the uterine changes that allow pyometra to occur.
Ref: https://www.amcny.org/pet_health_library/pyometra/
