Pyometra in Female Dogs: What Owners Need to Know Pyometra is a serious uterine condition that can develop in un-spayed female dogs. It involves inflammation of the uterus and the build‑up of fluid or discharge. While it is more common in older females, it can occur at any age, which is why awareness is so important. Who Is Most at Risk? Pyometra is most often seen in: Intact females over five years old Dogs experiencing repeated heat cycles Dogs with a history of hormonal fl