Few things strike fear in me, as a breeder and as the owner of one intact bitch, more than the thought of pyometra.

I had an experience several years ago with one of my older champion bitches who developed pyometra, and afterward I discovered that lots of people who breed and show dogs have never experienced it. It is something you want to recognize immediately when it happens because it can be fatal.

My Toy Poodle bitch was just over 6 years old. She had whelped one litter without any problems and didn’t take the next time I bred her. I hadn’t done much breeding for a while and was just enjoying having three older champions and one young bitch as house pets. Two of the girls had been in season just a few weeks before I noticed one day that one of them was listless and not interested in her dinner. This wasn’t one of those dogs that ate sometimes and not other times – she was one who always looked forward to her supper and never failed to clean her plate. But aside from skipping dinner, she just wasn’t herself. She always carried one of her dollies around in her mouth, and she was a big tail wagger. But not that afternoon. She just laid there with her head on her paws when I put down the food bowls.

Thank goodness I had worked for my vet for a few years and had seen pyometra. I immediately suspected the worst. So I took her to the vet right away, and at the time I was fortunate to live near Dr. John Hamil, in Laguna Beach, who as many readers will know is married to Susan Hamil; they breed and show Bloodhounds. Marcie was diagnosed immediately and Dr. Hamil let me know how grave the situation was – she needed to get to surgery quickly.

Marcie survived her bout with pyometra, but it was a very serious situation, and, had I waited even overnight, I am fairly sure I would have lost her. The key to knowing that you’ve got a bitch with pyometra is the connection between the fact that she’s recently been in season, and that she doesn’t feel well, or is not herself in some way. You always want to err on the side of caution if these two circumstances exist.

So what is pyometra, and what’s the connection with the reproductive cycle? Pyometra is an infection in the uterus that typically happens in middle-aged to older females. When a bitch comes into season, hormonal changes in her system, specifically an increase in progesterone levels, lead to a thickening of the lining of the uterus in preparation for the pregnancy. Progesterone levels remain elevated for eight to 10 weeks following the season, and the thickening of the walls of the uterus continues.

Also during the heat cycle, the cervix is open so that the sperm, if she’s bred, can travel up the reproductive tract to fertilize the eggs.

But when a bitch does not become pregnant, or if she hasn’t been pregnant for several heat cycles, the uterine lining continues to thicken until cysts begin to form. One reason it happens more often in older bitches – usually those that are 6 years of age or older – is because they’ve had more exposures to high levels of progesterone. The cysts that form in the uterine lining produce fluid that becomes an ideal breeding ground for bacteria to grow.

With the cervix open during the season, bacteria can enter the uterus, into the perfect environment created by the cysts. The bacteria then begin to multiply. This leads to the development of infection and pus.

Further complication results because high progesterone levels lead to a weakening of the muscles in the wall of the uterus, which means it can’t contract. This would be good if there were puppy fetuses forming — you wouldn’t want the litter to be aborted by uterine contractions. However, if the muscles of the uterus are too weak to contract with pyometra, the dangerous infection can’t be expelled. Pyometra typically progresses quickly, one reason it is life-threatening.

A bitch can have either of two types of pyometra: closed or open. In an open case,the cervix is not yet closed when the infection and pus develop, and they lead to a foul-smelling vaginal discharge that will alert you to the problem. A closed pyometra occurs when the cervix closes as the heat cycle ends, and the pus and infection are contained within the closed organ, which of course eventually leads to a very sick animal, since the infection is now trapped in the body. Very often dogs will exhibit no overt signs of illness until the infection reaches a dangerous level.

One sign to watch out for may be an increase in the frequency of urination, although many bitches already want to go out a little more frequently as they get older, so this may not seem unusual to you. A lack of appetite, drinking large amounts of water, listlessness or lethargy, or vomiting should all be cause for concern for a bitch that has recently been in season. Other signs may include a distended or swollen abdomen and the bitch washing around her vaginal opening more than usual.

Diagnosis and Treatment of Pyometra

A vet who has seen pyometra will likely diagnose it symptomatically on seeing an intact bitch that has recently been in season and is lethargic and exhibiting any of the other symptoms. The diagnosis can be verified using X-rays, ultrasound or blood tests. With an open pyometra, your veterinarian might take a swab to examine the discharge under a microscope.

I can’t emphasize enough that if you have even the slightest suspicion that a bitch who fits the profile is not feeling well, take her to the vet. Getting there and finding out that she has a urinary tract infection or something less harmful is far better than waiting and potentially losing her. The infection that builds up in the uterus can lead to its rupture, at which point the pus and bacteria spill into the abdominal cavity, causing a grave situation from which she might not be saved.

In most cases of pyometra, the optimum treatment is to remove the infected uterus and the ovaries. It is crucial that during the surgery, the uterus is not ruptured, as that will release the infection into the abdominal cavity. After the bitch is spayed and has had IV therapy and antibiotics at the vet hospital, she will typically need several weeks of recovery at home on antibiotics before she’ll be herself again.

Having her front leg shaved for the IV wasn’t the only evidence post-op that my Toy Poodle had been very ill. It took several weeks for her to fully recover from having pyometra.

Some vets will consider not spaying a bitch with pyometra – depending of course on the circumstances – if her owner intended to breed her again in the future. This requires much more complicated treatment, and in a closed pyometra, an attempt to drain the infection from the uterus. This is done using hormone therapies to attempt to decrease levels of progesterone, dilate the cervix and cause contraction of the uterus so that the infection will drain out. Antibiotic therapy is also in order.

However, there is no guarantee that treatment will work. With a closed pyometra, there is still the danger that the uterus will rupture, and in many cases the dog is too ill to survive until the treatment works fully. The infection may recur with subsequent seasons. Fertility is also reported to be lower in the future for bitches that have had pyometra.

In our case, Dr. Hamil’s staff took a photo of Marcie’s infected uterus after it was removed in surgery, and we compared it to a photo of a normal one. It was unbelievable how distended that small organ became. Instead of looking like a wrinkled, deflated balloon, it looked like a sausage casing that had been grossly overstuffed. Her entire uterus was obviously filled almost to bursting with infection. I’m glad I got to see it because it really cemented in my mind how dangerous the situation was, and how life-threatening.

Today I believe that most bitches should be spayed after they’ve had their last litter. I know from experience that on occasion people can believe they’ve bred a bitch for the last time, then later regret that they can’t breed her again for one reason or another. But pyometra was as frightening an experience as I’ve had with one of my dogs, and the only real way to prevent it is to spay them after they’ve had their last litter. In the meantime, keep an eye on your bitches after their seasons, I would say for four to six weeks, just in case any trouble occurs. And err on the side of caution if you see any unusual signs or behavior. No vet who has experienced pyometra would blame you if you came in with a false alarm.