Metritis in Cats: Uterine Infection After Giving Birth

By Dr Duncan Houston

A mother cat that stops eating, becomes withdrawn or neglects her kittens after birth should not be dismissed as simply tired. A uterine infection is one important possibility.

Her kittens may also be at risk if they are not receiving enough milk, warmth or care, so the whole family needs a plan.

Quick Answer

Metritis is inflammation and infection of the uterus, often developing after birth or pregnancy loss. Foul or pus-like discharge together with lethargy, poor appetite or reduced nursing warrants same-day veterinary assessment. Collapse, severe weakness, breathing difficulty or heavy bleeding require emergency care.

Why can metritis develop?

Difficult or prolonged labour, uterine injury and retained fetal material can contribute. Bacteria may multiply in the uterus and sometimes cause systemic illness. Metritis concerns the uterus as a whole; it should not be defined only as inflammation of its inner lining.

The MSD guidance on reproductive disorders in queens describes postpartum discharge and illness as important clues. Retained placentas do not invariably cause infection, and failing to see every placenta does not prove one remains inside.

What should you watch after birth?

Pay attention to appetite, energy, comfort, nursing and the appearance and smell of discharge. Some postpartum discharge can occur, but a foul smell, pus, increasing discharge or an unwell queen needs assessment. Cats may groom discharge away, so its absence does not exclude disease.

Kittens that cry persistently, fail to settle after nursing, feel cold or do not gain weight may be signalling a problem with maternal care or milk supply. Monitor each kitten rather than assuming an apparently busy nest is a healthy nest.

Risk and action guide

Finding	Concern	Action
Queen bright, eating and nursing, discharge not worsening	May be normal postpartum recovery	Continue observation and planned post-birth care
Foul discharge, poor appetite, lethargy or reduced nursing	Possible uterine or other postpartum disease	Veterinary assessment today
Collapse, heavy bleeding, marked weakness or severe pain	Possible sepsis, haemorrhage or another emergency	Emergency care immediately

What else can look similar?

Mastitis causes painful or abnormal mammary glands and can make nursing difficult. Low calcium can cause agitation, tremors or seizures. Retained kittens, continuing dystocia, urinary disease and other infections also need consideration. Pyometra is another uterine infection syndrome with a different reproductive context; it should not be assumed identical to postpartum metritis.

How is it diagnosed and treated?

The vet reviews the birth history, examines the queen and may use ultrasound or X-rays to assess the uterus and possible retained material. Blood tests assess inflammation, hydration and organ function. Samples for culture may help select antibiotics, interpreted alongside the site and examination.

Treatment includes appropriate antibiotics, pain relief and support according to severity. Drug choice must consider kittens that are nursing. Selected stable cats may be managed with close outpatient follow-up; others need hospitalisation or surgery to remove the infected uterus. Uterine-emptying medication is not a home remedy and is used only when appropriate after assessment. MSD's periparturient guidance discusses these individual treatment decisions.

When is this an emergency?

Go immediately if the queen collapses, becomes severely weak, has breathing difficulty, heavy bleeding, seizures or marked abdominal pain. Bring the kittens as directed by the clinic and keep them safely warm during transport. Do not delay because the mother briefly returns to the nest.

What should you do next?

Call with the delivery dates, number of kittens, any difficult labour and the queen's current signs.
Record food intake, nursing behaviour and discharge changes.
Weigh kittens consistently and seek prompt advice for poor gain, weakness or persistent crying.
Follow the clinic's nursing or supplementary-feeding plan, including whether temporary separation is necessary.
Attend the recheck and report failure to improve or renewed illness promptly.

Common mistakes

Assuming illness after birth is normal exhaustion.
Giving leftover oxytocin or antibiotics.
Forcibly pulling tissue from the vulva.
Treating the queen without considering kitten nutrition and warmth.

Reducing future risk

Plan pregnancy care, maintain a clean nest and seek early help for difficult labour. Discuss desexing once medically appropriate if future breeding is not intended. Good preparation lowers avoidable risks but does not make every complication preventable.

Frequently asked questions

Can kittens continue nursing?

Sometimes, but maternal condition and medication safety must be assessed by the vet.

Does missing a placenta mean infection?

No. Queens may eat placentas, and retention does not always cause disease.

Will she need surgery?

Not always. Severity, retained material and response guide the decision.

Can there be metritis without visible discharge?

Yes. Grooming and the nature of the infection can make discharge difficult to notice.

A sick queen needs prompt care, and her kittens need support at the same time. Early assessment helps protect both.

For help understanding your cat's health and preparing questions for your veterinary team, visit ASK A VET™. If your cat has emergency signs, contact an emergency clinic directly.