The name is certainly unique enough, but what does this term have to do with your pet? If you have an un-spayed female dog or cat, knowing this term is very significant. “Pyo” is the accumulation of pus, and “Metra” refers to the uterus. Yes, a pyometra is an infection of the uterus which is a large concern when it comes to an un-spayed female dog or cat.

Many people are informed that not spaying a dog before their first heat can lead to mammary cancer later in life. This is true, as the chance of developing mammary cancer increases with each passing heat cycle. A pyometra is a condition that is considerably overlooked, although if left undiagnosed and untreated can be just as deadly.

Pyometras generally occur within 4-8 weeks after a heat cycle. During heat, the uterus swells and thickens, increased blood flow occurs, and hormone levels change and rise. A dog or cat does not have to become pregnant for a pyometra to occur. It is not a miscarriage that has caused infection, but a combination of cystic growth, mucus, hormones, and bacteria from the birth canal.  It is more common in older dogs due to repeated heat cycles.

In dogs, the most common signs of a pyometra include drinking a lot of water, decreased appetite, vomiting, and lethargy.  You may also notice an enlarged abdomen and vaginal discharge, but this will not always be present.  If ever you have an intact female dog exhibiting those signs, have her seen by a veterinarian as soon as you can.  This is not a condition to wait on and see what happens or treat lightly.  This is a life-threatening disease, as bacteria and toxins in the uterus enter the bloodstream, causing sepsis. Your full-service veterinarian will be able to confirm a suspected case with bloodwork and x-rays, although sometimes an ultrasound exam is needed.

Cats often do not act sick until late in the course of the disease. A distended abdomen may be an early sign of pyometra in a cat, which you might mistake for a pregnancy.

Treatment for pyometra includes surgery to spay.  It is a much more serious surgery than a routine spay as the patient is usually very sick.  In addition, surgery will take longer, the incision will be larger, and hospitalization and supportive care is necessary.  It is therefore a much more expensive surgery than a routine spay. 

Prevention of pyometra is simple: spay your dog or cat. 

Maybe you have delayed spaying your dog or cat, and now you think that your pet is too old to have surgery.  It is usually never too late to spay your pet.  A pyometra is one of the many reasons to spay your dog or cat, especially if there is no intention or reason for breeding her. 


Kim Baumunk

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