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Pyometra: Why You Should Spay Sooner Than Later

Posted September 23, 2013 in Dog Diseases & Conditions A-Z

Dr. Justine Lee advocates on behalf of female dogs and cats everywhere: make sure you spay your pet sooner than later to avoid some scary complications. For more from Dr. Lee, find her on Facebook!

Most veterinarians advocate spaying and neutering for several reasons:

  • To help reduce pet overpopulation
  • To help prevent certain types of cancer (like breast or prostate cancer)
  • To help reduce certain unwanted behavioral issues (like aggression, dominance, sexual characteristics like humping, etc.)

While these are all excellent reasons for spaying and neutering, as an emergency specialist, I have my own additional bias on why I want owners to do it. I’m a big advocate of spaying or neutering your pet early in life because at some point, you’ll likely end up doing it due to medical reasons… and often times, on an emergency basis (which is much more expensive!). 

The biggest, most life-threatening reason why you want to spay and neuter? Pyometra.

Pyometra, which is a severe infection of the uterus, can be fatal to dogs and cats when untreated. In intact animals (those that aren’t spayed yet), the chronic effect of sex hormones can result in overstimulation of certain cells within the uterus called cystic endometrial hyperplasia (CEH). CEH can then progress in a severe E. coli infection and pus infection within the uterus. Typically, CEH occurs several weeks after a heat cycle, followed by a life-threatening pyometra shortly thereafter.

There are two types of pyometra infections: what we term “open” or “closed.” These terms refer to whether or not the cervix is open – in other words - draining out pus if it’s an “open” pyometra. If it’s a “closed” pyometra, it means you can’t actually see the pus drip out – all the pus is hidden away in the uterus instead. 

“Open” pyometras are easier to diagnosis due to foul, malodorous, bloody green discharge from your pet’s vulva. “Closed” pyometras can be harder to diagnose, as the signs aren’t as obvious to pet owners. As a result, “closed” pyometras are more life-threatening as they are under-recognized. As pets often hide their signs until they are very severe, pet owners may not realize their pet has a life-threatening infection in their uterus. Without treatment (which is almost always surgically treated with an emergency ovariohysterectomy), the uterus can rupture, resulting in a severe bacterial infection in both the abdomen and in the blood

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Justine has more than 18 years of experience in the veterinary industry and is a board-certified emergency critical care veterinary specialist and toxicologist as well as the CEO and founder of Vetgirl. She is also a founding member of IDEXX’s Pet Health Network team.