Spontaneous Abortion in Cats

Only purebred cats have a predisposition for non-infectious related spontaneous abortion during pregnancy. However, cats that have previously experienced complications during pregnancy have a higher risk for spontaneous abortion.

Pregnant cats that experience spontaneous abortion may do so for a number of reasons, including bacterial or viral infection, disease, and reproductive issues. Spontaneous abortion is more common in the later stages of the pregnancy, and may not affect all the kittens of a litter.

Some cats that have had a spontaneous abortion may not show any symptoms at all. The most common symptom observed in cases of abortion is abnormal vaginal bleeding. You’ll need to seek immediate veterinary attention as soon as you notice any of the following symptoms in your cat:

• Abnormal bleeding from the vagina
• Discharge or pus in the vaginal area
• Going back into heat/estrus
• Delivered fetal or placental tissue*
• Smaller abdominal size
• Signs of pain or discomfort
• Depression
• Vomiting and/or diarrhea
• Loss of appetite
• Weight loss
• Fever
• Dehydration

*It is imperative that you do not touch any aborted fetal or placental material with your bare hands, as some infectious causes of spontaneous abortion can spread to humans. Contact your veterinarian immediately if you have any doubts about disposing of this material in a sanitary manner.

There is a myriad of causes for spontaneous abortion in cats. Cats that have suffered from pregnancy complications in the past have an increased risk of spontaneous abortion. Purebred cats, due to a history of inbreeding, also have a higher chance of experiencing spontaneous abortion than mixed breeds.

Many infectious diseases can also cause spontaneous abortion. Some of the most common viral infections that are causative of spontaneous abortion include feline herpesvirus, feline immunodeficiency virus, and feline leukemia. Certain species of bacteria and protozoa may also spread from the vagina into the womb during breeding, resulting in spontaneous abortion.

Reproductive issues may also be responsible for spontaneous abortion in felines. These issues can include but are not limited to, hormonal conditions, genetic defects within the fetus, problems with placenta development, dystocia, and endometrial disease.

Some spontaneous abortions may not be caused by disease or the reproductive system at all. Extreme malnutrition, stress, and trauma can also play a role in abortion. In some cases, abortion can be caused by systemic diseases affecting other parts of the body. Certain types of medications can also cause spontaneous abortion in cats.

Be sure to inform the vet of the extent and duration of your cat’s symptoms, any currently prescribed medications, and any previous spontaneous abortions or pregnancy problems. They may request a complete medical history, so be prepared to provide it.

Your vet will make a definitive diagnosis by performing an x-ray of the abdomen to determine whether any fetuses still remain in the womb. The vet will also test for other underlying diseases during this time, and may utilize a number of diagnostic methods, including blood count, urinalysis, and a test for feline leukemia virus.

The method of treatment will vary depending on the cause. Treatment may be more or less invasive depending on whether or not the cause is infectious. Your vet will advise you on the best course of treatment based on your cat’s specific needs.

Infectious Causes

Abortions caused by underlying illness or infection may require hospitalization. Affected cats must be isolated in order to prevent spread of the disease. Specific treatment will vary based on the underlying disease or infection. If your cat has developed dehydration, intravenous fluid therapy may also be utilized.

Non-infectious Causes

Surgery may be required for cats suffering from certain conditions, particularly inflammation in the reproductive organs, or if the spontaneous abortion is life-threatening. Drug therapy, specifically terbutaline, may also be required to ensure the pregnancy endures. In some cases, treatment may not be necessary for otherwise healthy cats that have experienced spontaneous abortion. 

Recovery and prognosis will depend on the underlying cause of spontaneous abortion in your cat. Always follow your vet’s post-treatment instructions carefully.

If your cat has been prescribed antibiotics for a bacterial infection, it is imperative that you administer the medication for the entire recommended duration of treatment, even if the symptoms begin to clear up. Failure to do so may result in aggressive recurrence of the infection and future reproductive problems.

The vet will likely schedule one or several follow-up appointment(s), particularly if your cat has been prescribed terbutaline or another drug to maintain the pregnancy. In these cases, an ultrasound will be required once a week to monitor the progress of the pregnancy.