Is Your Furry Feline Putting You at Risk of Miscarriage?

Updated December 30, 2014.

Question: Did My Cat Give Me Toxoplasmosis and Cause My Miscarriage?

Once upon a time, doctors used to routinely advise pregnant women to avoid cats -- leading many women to give up their cats or to worry over even the tiniest cat scratch during pregnancy. But do cats really increase risk of miscarriage?

Answer:

It is true that cats can be carriers of the microorganism known as Toxoplasma gondii, the cause of the disease toxoplasmosis.

It is also true that toxoplasmosis is one of several infections that can cause miscarriage.

However, this does not mean that having a cat automatically puts you at risk of miscarriage. In fact, the risk of having a cat while pregnant is sometimes rather exaggerated. One study in 2000 of several large European studies actually found that the largest risk of toxoplasmosis in pregnancy was from eating undercooked meat, and cat ownership was rarely a problem.

Reasons Why Cats Rarely Transmit Toxoplasmosis to Pregnant Women

First of all, cats are not usually chronic carriers of T. gondii. They tend to acquire it, and then they develop antibodies and they no longer transmit T. gondii. So, in order for a house cat to pass toxoplasmosis to its owner, the cat itself would have to have had a recent exposure to T. gondii itself -- and to not have circulating antibodies against the infection.

Second, outdoor cats tend to be exposed to T. gondii far more frequently than indoor cats; toxoplasmosis in indoor cats is rare.

T. gondii are most commonly found in rodents and raw meat, so a cat who lives only indoors is unlikely to be exposed unless the owner regularly feeds the cat raw meat.

Finally, the means of transmission from cat to owner would most likely be through exposure to cat feces. The woman would have to change the cat litter box, then somehow put the T. gondii into her mouth -- and it's safe to say that most people would probably wash their hands in between changing cat litter and touching their mouths!

Sensible Precautions for Cat Owners

All in all, the risk of acquiring T. gondii from a house cat is rather low. That being said, the CDC suggests the following precautions in order to almost entirely eliminate your risk of cat-borne toxoplasmosis:

Get someone else to change the cat litter if you can, and if you can't, wear gloves and wash your hands carefully after changing the box.
Change cat litter daily; T. gondii are infectious between 1 and 5 days after the cat defecates
Do not feed your cat raw meat, and keep your cat indoors.
Be careful around stray cats and kittens, and avoid getting a new cat while pregnant.
Keep outdoor sandboxes covered, and wear gloves when gardening in case an outdoor cat has defecated in your garden.

_Sources:
_{Centers for Disease Control and Prevention, "Toxoplasmosis - Pregnant Women." 11 Jan 2008. Accessed 7 Feb 2008.}_{Cook, A.J.C., R.E. Gilbert, W. Buffolano, J. Zuffery, P.A. Jenum, W. Foulon, A.E. Semprini, and D.T. Dunn, "Sources of toxoplasma infection in pregnant women: European multicentre case-control study. British Medical Journal 2000. Accessed 7 Feb 2008.}_{Humane Society of the US, "Pregnancy and Toxoplasmosis." Pet Care. Accessed 7 Feb 2008.}