Pyometra in Dogs: The Emergency Behind a Missed Heat

Pyometra is a pus-filled uterus. It shows up most often in the weeks after a heat cycle in an intact (unspayed) female, not because she "missed" a heat. She may be middle-aged or older. She can also be younger. If she still has a uterus, she is the patient at risk.

This is not a wait-and-see problem. Untreated pyometra can progress to sepsis (a bloodstream infection) and can be fatal. Caught early and treated with surgery, many dogs recover. The risk climbs when treatment is delayed. If you think this might be happening, come in during True Animal Vet hours or go to the nearest ER if we are closed.

What pyometra is

After a heat, the uterus is under the influence of hormones that thicken the lining and quiet the immune response in that tissue. Bacteria can take hold. The uterus fills with pus. That is a pyometra case.

It typically appears weeks after she was in heat, not on the day the bleeding stopped. If you have an intact female and she seems "off" a few weeks after a cycle, do not write it off as a leftover heat. Call us immediately.

Spaying removes the uterus, which is how most pyometra is prevented. Rare cases can still occur in remaining tissue after an incomplete spay. This post is not about when to spay. It is about the emergency in a female dog who is still intact. If she is intact and sick after a heat, treat that as urgent.

Intact means she has not been spayed. A dog who had one heat, or many heats, can still get pyometra. Age raises the odds, but this is not a senior-only disease.

Open pyometra and closed pyometra

There are two presentations, and the difference matters.

Open pyometra means the cervix (the opening of the uterus) is open enough for discharge to drain from the vulva. You may see pus, bloody pus, or a foul discharge on her fur, bedding, or the floor. That discharge is a clue. It does not make the infection safe. She still needs treatment.

Closed pyometra means little or no discharge. The pus stays inside. The uterus can swell. She can get sicker faster because nothing is leaking out to warn you. Closed pyometra is more dangerous for that reason. Do not wait for discharge to appear before you worry.

Either type can make her systemically ill. Either type can kill her without treatment.

Signs that mean come in now

Watch for a dog who is drinking and urinating more, acting lethargic, vomiting, or eating less. She may have a fever, or her temperature may run low. Her abdomen may look or feel swollen. You may see vaginal discharge, or you may not.

She may just seem dull and thirsty a few weeks after a heat. That is enough. You do not need every sign on the list. Closed cases especially can look like "she has a virus" until they do not.

When you call, say she is intact, when her last heat was if you know it, and what you are seeing: discharge, thirst, vomiting, a swollen belly, or just that she is dull. That short list gets her triaged faster than "she seems off."

If she is collapsing, unresponsive, or declining fast, that is an emergency now. During True Animal Vet hours, come to either hospital. We can evaluate her, stabilize her, and do the surgery when that is the plan. If she is crashing and we are about to close, or we are already closed, go to a 24-hour ER, then call us when we reopen.

Treatment is emergency surgery

Typical treatment is emergency surgery to remove the uterus and ovaries (ovariohysterectomy), with IV fluids and antibiotics. That is the standard approach for a reason. Leaving an infected uterus in place keeps the source of the sepsis in her body. This is not the same surgery as a routine healthy-dog spay. How sick she is changes how much support she needs around the procedure.

Pills are not a substitute for surgery in a typical pyometra case. If a doctor has told you the uterus needs to come out, that is the treatment that removes the source of the infection.

How sick she is on arrival affects the plan around surgery: stabilization, fluids, labs, and how soon she goes to the operating table. The destination is still removing the infected uterus in a typical case.

If we are open, give us a call. We evaluate and operate on pyometra at both hospitals during open hours. If we are closed, go to the nearest ER. When we reopen, call us so we can help with the next steps.

How to reach us

If your intact female is drinking more, dull, vomiting, or leaking discharge in the weeks after a heat, get her examined. Call The Woodlands at (281) 867-5968 (4524 Research Forest Dr, The Woodlands, TX 77381) or Grand Oaks at (281) 869-3010 (4970 Riley Fuzzel Rd, Spring, TX 77386). Text (281) 916-3282. Hours are Monday through Friday 7:30am to 9pm, Saturday 8am to 12pm, Sunday closed. If we are closed, go to the nearest ER, then call True Animal Vet when we reopen.