Pyometra Dogs and cats

Pyometra is secondary bacterial infection in dogs and cats ,it’s one of life threatening medical reproductive health emergencies we counter at our surgery.Pyometra simply means pus in the uterus .

This is a life threatening disease in old and intact (un spayed) female cats and dogs. It occurs between two weeks and eight weeks post estrus (heat cycle).

How does this happen?

There are many factors which contribute to this condition in intact female cats and dogs.

When your female cat or dog goes into heat and you don’t serve them (allowing her to mate) there is an increased progesterone level in blood in estrus. This causes hormonal imbalance which causes thickening of the uterine wall and formation of cysts.

This cause a condition called cystic endometrial hyperplasia, these cysts get filled with fluid from secretions which creates and ambient environment for bacterial growth.

Due to thickened uterine wall there is reduction in uterine contraction so this fluid can not be expelled out.

Another factor that favors pyometra is the fact that white blood cells which woul have protected the uterus from getting infection are inhibited from reaching the uterus during this period due to progesterone influences.

At the same time the cervix is relaxed and open this allows entry of bacteria in the uterus.

Cause of pyometra

Use of progesterone based anti puppy birth control methods in dogs.

Hormonal imbalances as results unserved dogs during estrus and progesterone surge in late estrus.

Use of estrogen based medication in intact female cats and dogs.

How do I know that my dog has pyometra?

Generally the dog becomes weak, loses appetite, starts vomiting and becomes anorexic with severe elevated white blood cell count.

Generally there two types of pyometra ,closed and open pyometra.

In open pyometra you will notice cream foul smelling discharge from your dog’s vulva. Your furry friend will be taking lots of water though with low appetite.

I closed pyometra there will be no discharge of pus from the vulva . However you will notice a distended abdomen, your pet will be taking a lot of water and she will be lethargic.


For dogs which are intended for breeding medical treatment is possible with variable out comes .

We recommend surgical treatment which involves removal of the uterus and ovaries. With this method your furry friend will not be able to conceive.

It’s important to note from our experience that closed pyometra is more life threatening than open pyometra. The prognosis is usually poor due to spread of these bacterial toxins in blood which usually results into systemic inflammatory response and septic shock.


By serving you dog when they come on heat .

Avoid use of hormonal birth control injection which are progesterone based.

Surgical treatment of pyometra.

Cystic endometrial hyperplasia
Uterus filled with pus

Discharge from the vulva

Discharge from the vulva above .

Cat’s uterus filled with pus .

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