Pyometra in Dogs and Cats: A 2025 Vet Emergency Guide by Dr Duncan Houston 🐾🧫

By Dr Duncan Houston, BVSc | July 2025

💥 What Is Pyometra?

Pyometra is a life-threatening uterine infection that occurs in unspayed female dogs and cats. The term comes from “pyo” (pus) and “metra” (uterus)—and that’s exactly what it is: a pus-filled, infected uterus. This condition releases toxins into the bloodstream and can lead to sepsis, organ failure, and death if untreated. ⏳

🐕 Common Risk Factors

🚺 Female pet is intact (not spayed)
📆 Usually occurs 1–2 months after a heat cycle
📈 More common with age due to cumulative hormonal exposure

🔍 Types of Pyometra

Open Pyometra: Cervix is open, pus drains visibly from the vulva. Less severe initially, but still an emergency. 💧
Closed Pyometra: Cervix is closed, trapping pus inside. More dangerous—no discharge means delayed diagnosis. 🚨

⚠️ Signs to Watch For

💦 Vaginal discharge (in open pyometra)
🥵 Fever, lethargy, vomiting, inappetence
💧 Excessive drinking and urination
📉 Weakness or collapse (in late stages)
🐕 Distended belly (especially in closed pyometra)

🧪 Diagnosis

🩺 Physical exam and history
🧪 Bloodwork showing infection and toxicity
📸 X-rays or ultrasound to visualize enlarged uterus

🛠️ Treatment Options

🚨 Emergency Surgery (Preferred)

💉 Removal of uterus and ovaries
🧼 Avoid rupture and spillage of pus into abdomen
💊 IV antibiotics and pain management
🏥 Hospitalization typically required for 2–3 days

This is not a routine spay—it’s a higher-risk, emergency procedure that costs significantly more.

💉 Hormonal Therapy (Rare)

📆 Uses prostaglandin injections to expel pus
📛 Only for open pyometra and select breeding candidates
⏳ Recovery takes a week or more
🐾 Requires breeding on the next cycle or risk recurrence

🐈 Special Note on Cats

Feline pyometra is equally dangerous but harder to detect:

😼 Cats may groom away discharge, hiding symptoms
🥣 They often appear “normal” until late in disease
⚠️ Delayed diagnosis is common and dangerous

⚠️ Stump Pyometra

If a dog or cat has been spayed but still shows signs of pyometra, the cause may be a stump pyometra—an infection in uterine tissue accidentally left behind. It usually results from:

💉 Ovarian remnant producing hormones
🧴 Topical estrogen exposure from humans

Stump pyometra requires exploratory surgery and hormone testing. 🧪

📋 Pyometra Summary Table

Type	Symptoms	Treatment	Urgency
Open	Discharge, moderate signs	Surgery or prostaglandins	High
Closed	No discharge, severe illness	Emergency surgery	Critical
Feline	Subtle signs, discharge	Surgery preferred	High
Stump	Signs in spayed pet	Surgery + hormone source ID	High

🛡️ Prevention: Spay Early

Spaying is 100% preventative against pyometra. Don’t wait until your pet is older or after “just one litter.” The risks rise with every heat cycle. 🩺

🔧 Ask A Vet Can Help

Worried your dog or cat has pyometra? Use the Ask A Vet app for symptom screening, emergency triage, and support planning for surgery or hormone treatment. 📱🐾

🐾 Final Thoughts from Dr Duncan Houston

Pyometra is one of the most dangerous—but preventable—diseases in veterinary medicine. Spaying saves lives. If your pet shows any signs, don’t wait. Time matters. 💙🧫

— Dr Duncan Houston, BVSc

Visit AskAVet.com or download the Ask A Vet app for urgent help with pyometra, spay planning, and reproductive care. 📱