Pyometra – A Dog’s Medical Emergency

Pyometra can be a silent and deadly killer. It is extremely important that you can recognise the signs and symptoms as should your dog develop Pyometra, she will need an emergency operation.

Pyometra is one of the most serious life-threatening conditions for any female dog to suffer from. Pyometra literally means ‘pus in the womb’.

Although Pyometra is a lot less common than it once was (as more and more dog owners are neutering their girls if they are not to be bred from) there are still a lot of cases that are claiming the lives of thousands of dogs each year.

Signs & Symptoms

There are a wide range of symptoms of Pyometra (or ‘pyo’ for short) and it can be noticeable by a thick (often brownish) pus seeping from her vulva, to less clear symptoms such as her being a bit quiet and off her food.

The reason for this wide variety of clinical signs can be due to how long the pyo has been established and whether the pus is being allowed to drain out from the womb (‘open’ pyo) or not (‘closed’ pyo). Both are very serious, but closed pyometra has a higher risk of being fatal due to less obvious symptoms, which may only be recognised once it is too late. That is why it is extremely important you are aware of pyo and it’s signs and symptoms.

Open Pyometra

The signs of ‘open’ pyo is where her cervix is open, allowing the pus being produced in the uterus to freely flow outside the body and be visible on examination. An example of open pyo would be, an unspayed female with a noticeably increased thirst (polydipsia) who seems to be spending most of her time licking an abnormal foul-smelling, brown/green coloured discharge from her private parts.

Closed Pyometra

In less obvious, ‘closed’ pyo situations, the cervix remains tightly closed, withholding the pus inside her uterus and making the condition less obvious to diagnose. Her abdomen could be swollen and painful to touch and she may show signs of her being tired, depressed, and turning her nose up at food – including her favourite treats. By the time you see any of these external signs, however, the condition is in a fairly advanced stage, so you’ll need to get medical attention right away.

In either case, she may have a fever (a dogs normal temperature is between 101 to 102.5 degrees Fahrenheit, or 38.3 to 39.2 degrees Celsius), have greyish gums (depending how advanced the pyo is) and she will have been in season between one and three months ago. She may also be vomiting and having diarrhoea.


The first thing your vet will do if they suspect pyometra is a thorough examination of her abdomen. The vet may perfom blood tests and an ultrasound of her abdomen. This is a useful, non-invasive method of checking whether a swollen abdomen is caused by infection and not by pregnancy. Your vet will take a sample of the discharge for testing, to determine what type of bacteria is causing the infection. Depending on how ill the dog is, she might need to stay overnight in the veterinary hospital for treatment.


Pyometra can be caused by one or a combination of underlying causes. For instance, it can be the tiny, microscopic behaviour of the womb lining itself, likely hormonal imbalances. Or in some cases, a source of infection that usually enters the reproductive tract at the vulva from the outside world and creeps up, or comes via the blood stream from another infected area of the body. If the dog has also recently given birth to a litter, an inflamed womb with bruised or exhausted and vulnerable tissues, can also act as a focus for infection to set in.


The most common treatment for all pyometra cases, and the only option for a closed infection, is surgery to remove the dog’s uterus (spay). This is a difficult, high-risk operation because if the infection spills during removal it can be dangerous for the dog. Your vet may advise that, as many animals with severe pyometra show signs of being toxic or even shock, they may benefit from intravenous fluids, antibiotics and pain relief first to best prepare for the surgery.

Pyometra is one of the biggest reasons vets advise you to get your female spayed if you’re not planning to breed from her. Spaying a dog with pyometra is usually 100% successful, with her typically making a full and uneventful recovery with a good prognosis.